Diabetes is a widespread disease affecting millions of people,making it one of the leading causes of death in the world.It is a leading cause of cardiovascular disease and end-stage renal disease.Despite advancements ...Diabetes is a widespread disease affecting millions of people,making it one of the leading causes of death in the world.It is a leading cause of cardiovascular disease and end-stage renal disease.Despite advancements in treatment,including insulin therapy and glucose monitoring devices,diabetes continues to significantly impact quality of life and current modalities do not reverse the end-organ damage associated with its progression.While traditionally indicated for type 1 diabetes,recent clinical practice refinements have made pancreas transplants available to select type 2 diabetics meeting specific criteria.These transplants are usually a part of a simultaneous kidney-pancreas transplant.However,although less frequently performed,transplants of pancreas alone or pancreas after kidney transplant are still available.For selected diabetic patients,pancreas transplants offer significant survival benefits and the improvement of cardiovascular and metabolic complications;however,they are not without risks.Complications such as bleeding,vascular thrombosis,infection,organ leak,and rejection are possible.Another challenge to pancreas transplantation is the decreasing number of procedures being performed due to decline in the volume of available highquality allografts and resource constraints of transplant centers.Advancements in monitoring and treatment of diabetes are contributing to the decline in pancreas transplants nowadays.展开更多
Intrapancreatic fat deposition(IPFD)has garnered increasing attention in recent years.The prevalence of IPFD is relatively high and associated with factors such as obesity,age,and sex.However,the pathophysiological me...Intrapancreatic fat deposition(IPFD)has garnered increasing attention in recent years.The prevalence of IPFD is relatively high and associated with factors such as obesity,age,and sex.However,the pathophysiological mechanisms underlying IPFD remain unclear,with several potential contributing factors,including oxida-tive stress,alterations in the gut microbiota,and hormonal imbalances.IPFD was found to be highly correlated with the occurrence and prognosis of exocrine pan-creatic diseases.Although imaging techniques remain the primary diagnostic approach for IPFD,an expanding array of biomarkers and clinical scoring systems have been identified for screening purposes.Currently,effective treatments for IPFD are not available;however,existing medications,such as glucagon-like peptide-1 receptor agonists,and new therapeutic approaches explored in animal models have shown considerable potential for managing this disease.This paper reviews the pathogenesis of IPFD,its association with exocrine pancreatic disea-ses,and recent advancements in its diagnosis and treatment,emphasizing the significant clinical relevance of IPFD.展开更多
BACKGROUND: The good therapeutic effects of large dose of dexamethasone on severe acute pancreatitis (SAP) patients have been proved. This study was designed to investigate the influence of dexamethasone on apoptosis ...BACKGROUND: The good therapeutic effects of large dose of dexamethasone on severe acute pancreatitis (SAP) patients have been proved. This study was designed to investigate the influence of dexamethasone on apoptosis of acinar cells in the pancreas of rats with SAP and the protein expression of the apoptosis-regulating genes Bax and Bcl-2. METHODS: Ninety Sprague-Dawley rats with SAP were randomly divided into a model group and a dexamethasone treated group (45 rats in each group), and another 45 rats formed the sham operation group. Survival rates were calculated and gross pathological changes in the pancreas of each group were observed under a light microscope 3, 6 and 12 hours after operation. Tissue microarray technology was applied to prepare pancreatic tissue sections. The changes in Bax and Bcl-2 protein expression levels of pancreatic tissues from each group were assessed by immunohistochemical staining, and TUNEL staining was used to evaluate changes in apoptosis index. RESULTS: The model and treated groups did not differ in mortality at each time point. The pathological score for the pancreas in the treated group was significantly lower than that in the model group at 3 and 6 hours. The positive rates of Bax protein expression in the head and tail of the pancreas in the treated group at all time points were all markedly higher than those of the model group. The positive rate of Bcl-2 protein expression in the head of the pancreas in the treated group was significantly higher than that of the model group at 3 hours. TUNEL staining showed that the pancreas head and tail apoptosis indices of the treated group were markedly higher than those of the model group after 6 hours. CONCLUSIONS: Apoptosis may be a protective response. to pancreatic cell injury. The mechanism of action of dexamethasone in treating SAP may be related to the apoptosis of acinar cells in the pancreas induced by apoptosis-regulating genes such as Bax and Bcl-2. The advantages of tissue microarrays in pathological examination of the pancreas include saving of time and energy, efficiency and highly representative.展开更多
Giant cell tumors of the pancreas come in three varieties-osteoclastic,pleomorphic,and mixed histology.These tumors have distinctive endoscopic,clinical,and cytological features.Giant cell tumors have a controversial ...Giant cell tumors of the pancreas come in three varieties-osteoclastic,pleomorphic,and mixed histology.These tumors have distinctive endoscopic,clinical,and cytological features.Giant cell tumors have a controversial histogenesis,with some authors favoring an epithelial origin and others favoring a mesenchymal origin.The true origin of these lesions remains unclear at this time.These are also very rare tumors but proper identification and differentiation from more common pancreatic adenocarcinoma is important.The risk factors of these tumors and the prognosis may be different from those associated with standard pancreatic adenocarcinoma.Recognition of these differences can significantly affect patient care.These lesions have a unique appearance when imaged with endoscopic ultrasound(EUS),and these lesions can be diagnosed via EUS guided Fine Needle Aspiration(FNA).This manuscript will review the endoscopic,clinical,and pathologic features of these tumors.展开更多
BACKGROUND: Giant cell tumors are rare and highly malignant tumors of the pancreas. Based on two distinct cell populations, they have been divided into two subtypes corresponding to the osteoclast-like giant cell tumo...BACKGROUND: Giant cell tumors are rare and highly malignant tumors of the pancreas. Based on two distinct cell populations, they have been divided into two subtypes corresponding to the osteoclast-like giant cell tumor and the pleomorphic giant cell carcinoma of the pancreas. Distinctive imaging features of the tumors remain uncharacterized. Surgical removal is the only appropriate treatment for them, but responses to chemotherapy or radiotherapy remain undocumented. METHODS: Clinical, radiological, histopathologic, and immuno- histochemical features of two cases of giant cell tumor of the pancreas are presented along with a brief review of the literature. RESULTS: En-bloc resection was done successfully in both cases. The patient with an osteoclast-like giant cell tumor remained disease-free with no clinical or radiological evidence of recurrence at 6 months after surgery. However, the patient with the pleomorphic type died 4 months later due to diffuse pulmonary metastasis. CONCLUSIONS: En-bloc surgical resection is the only appropriate treatment for giant cell tumors. The overall prognosis of these tumors is poorer than that of pancreatic ductal adenocarcinoma, especially the pleomorphic type. More studies are required to document the management and outcomes of the tumors.展开更多
Since the first description of intraductal papillary mucinous neoplasms(IPMNs)of the pancreas in the eighties,their identification has dramatically increased in the last decades,hand to hand with the improvements in d...Since the first description of intraductal papillary mucinous neoplasms(IPMNs)of the pancreas in the eighties,their identification has dramatically increased in the last decades,hand to hand with the improvements in diagnostic imaging and sampling techniques for the study of pancreatic diseases.However,the heterogeneity of IPMNs and their malignant potential make difficult the management of these lesions.The objective of this review is to identify the molecular characteristics of IPMNs in order to recognize potential markers for the discrimination of more aggressive IPMNs requiring surgical resection from benign IPMNs that could be observed.We briefly summarize recent research findings on the genetics and epigenetics of intraductal papillary mucinous neoplasms,identifying some genes,molecular mechanisms and cellular signaling pathways correlated to the pathogenesis of IPMNs and their progression to malignancy.The knowledge of molecular biology of IPMNs has impressively developed over the last few years.A great amount of genes functioning as oncogenes or tumor suppressor genes have been identified,in pancreatic juice or in blood or in the samples from the pancreatic resections,but further researches are required to use these informations for clinical intent,in order to better define the natural history of these diseases and to improve their management.展开更多
Objective:To evaluate the consequence of oral administration of Calliandra portoricensis(C. portoricensis) leaf extract on the stomach and pancreas in Swiss albino mice.Methods:Three, groups of mice(B,C and D) were tr...Objective:To evaluate the consequence of oral administration of Calliandra portoricensis(C. portoricensis) leaf extract on the stomach and pancreas in Swiss albino mice.Methods:Three, groups of mice(B,C and D) were treated with 4 mg/kg of C.portoricensis extract.Croup A was the control and received an equivalent volume of distilled water.Group B received C.portoricensis leaf extract for 7 days.Croup C received C.portoricensis leaf extract for 14 days,and Croup D received C.portoricensis leaf extract for 28 days.At different stages in the study,the mice were sacrificed and the stomach and pancreas were excised and fixed in 10%formol saline for histological analysis.Results:The result showed a normal microstructural outline in groups B and C as compared with the control.However,animals in group D showed disorganization of the mucosa and discontinuation of epithelial lining of the stomach while the islets of Langerans in the pancreas were at various degree of degeneration as compared with the control mice. Conclusions:The present finding suggests that chronic administration(28 days as seen in this study) of C.portoricensis leaf extract may inhibit the proper function of the stomach and pancreas.展开更多
Intraductal papillary-mucinous neoplasm(IPMN) of the pancreas is a clinically and morphologically distinctive precursor lesion of pancreatic cancer,characterized by gradual progression through a sequence of neoplastic...Intraductal papillary-mucinous neoplasm(IPMN) of the pancreas is a clinically and morphologically distinctive precursor lesion of pancreatic cancer,characterized by gradual progression through a sequence of neoplastic changes.Based on the nature of the constituting neoplastic epithelium,degree of dysplasia and location within the pancreatic duct system,IPMNs are divided in several types which differ in their biological properties and clinical outcome.Molecular analysis and recent animal studies suggest that IPMNs develop in the context of a field-defect and reveal their possible relationship with other neoplastic precursor lesions of pancreatic cancer.展开更多
AIM: To report the clinicopathological features and magnetic resonance imaging (MRI) findings of solid and pseudopapillary tumor (SPT) of pancreas.METHODS: From 1981 to 2005, 26 surgically treated cases of SPT were re...AIM: To report the clinicopathological features and magnetic resonance imaging (MRI) findings of solid and pseudopapillary tumor (SPT) of pancreas.METHODS: From 1981 to 2005, 26 surgically treated cases of SPT were retrospectively reviewed. MRI findings of the latest 11 consecutive SPT cases were investigated.RESULTS: There were 25 women and one man having SPT (median age: 23 year) with a median tumor size of 7.5 cm. Among them, nine patients developed solid pseudopapillary carcinoma. During the median follow-up period of 66 mo, the 5-year survival rate of the 26 SPT patients was 96.2%. Three MRI features were proposed including Type 1 image, displaying SPT with completely solid part. All SPT patients with type 1 image were detected incidentally. Type 2 image displays of SPT with solid mass hemorrhage and type 3 image with massive hemorrhage. All the eight SPT patients with type 2 and 3 images suffered abdominal pain due to hemorrhage from SPT.CONCLUSION: SPT had a favorable survival rate irrespective of surgical procedures, malignancy, and MRI findings, however, MRI could reliably correlate with its clinicopathological features.展开更多
Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospecti...Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.展开更多
Recently, a novel and distinct pancreatic cystic tumor termed 'mudnous nonneoplastic' cyst was described in the literature. We report our experience with a 71-year-old female with a cystic tumor in the body of...Recently, a novel and distinct pancreatic cystic tumor termed 'mudnous nonneoplastic' cyst was described in the literature. We report our experience with a 71-year-old female with a cystic tumor in the body of the pancreas demonstrating features suggestive of this diagnosis. We also review the literature regarding this 'novel' pathological entity and discuss critically its existence and its differential diagnoses.展开更多
BACKGROUND A solitary fibrous tumor(SFT)is often located in the pleura,while SFT of the pancreas is extremely rare.Here,we report a case of SFT of the pancreas and discuss imaging,histopathology,and immunohistochemist...BACKGROUND A solitary fibrous tumor(SFT)is often located in the pleura,while SFT of the pancreas is extremely rare.Here,we report a case of SFT of the pancreas and discuss imaging,histopathology,and immunohistochemistry for accurate diagnosis and treatment.CASE SUMMARY A 54-year-old man presented to our hospital with pancreatic occupancy for over a month.There were no previous complaints of discomfort.His blood pressure was normal.Blood glucose,tumor markers,and enhanced computed tomography(CT)suggested a malignant tumor.Because the CT appearance of pancreatic cancer varies,we could not confirm the diagnosis;therefore,we performed endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB).Pathology and immunohistochemistry were consistent with SFT of the pancreas.The posto-perative pathology and immunohistochemistry were consistent with the puncture results.The patient presented for a follow-up examination one month after discharge with no adverse effects.CONCLUSION Other diseases must be excluded in patients with a pancreatic mass that cannot be diagnosed.CT and pathological histology have diagnostic value for pancreatic tumors.Endoscopic puncture biopsy under ultrasound can help diagnose pancreatic masses that cannot be diagnosed preoperatively.Surgery is an effective treatment for SFT of the pancreas;however,long-term follow-up is strongly recommended because of the possibility of malignant transformation of the tumor.展开更多
Annular pancreas is a rare congenital anomaly formed by a thin band of pancreatic tissue that encircles the descending duodenum and leads to partial or complete obstruction.Annular pancreas is estimated to occur in le...Annular pancreas is a rare congenital anomaly formed by a thin band of pancreatic tissue that encircles the descending duodenum and leads to partial or complete obstruction.Annular pancreas is estimated to occur in less than 5/100,000 people;however,the true incidence is unknown given that annular pancreas is frequently asymptomatic and only an incidental finding on cross-sectional imaging or autopsy examination.1,2 When symptomatic,patients typically present with abdominal pain,nausea and vomiting,or postprandial fullness due to gastric outlet obstruction.3 Other and less common presentations include peptic ulcer disease,biliary obstruction,or symptoms of acute or chronic pancreatitis.展开更多
Obesity is a major contributor to metabolic dysfunction,and its impact on pancreatic health has garnered increasing attention.Macrophages,as key regulators of inflammation and metabolism,play a central role in mediati...Obesity is a major contributor to metabolic dysfunction,and its impact on pancreatic health has garnered increasing attention.Macrophages,as key regulators of inflammation and metabolism,play a central role in mediating obesity-induced pancreatic damage.In obese individuals,excessive lipid accumulation and chronic low-grade inflammation drive the infiltration and polarization of macrophages within the pancreas.These macrophages,particularly the pro-inflammatory Macrophage,pro-inflammatory phenotype(M1)phenotype,secrete cytokines such as C-C motif ligand 2(CCL2)and transforming growth factor beta(TGF-β),which disrupt pancreaticβ-cell function and impair insulin secretion.Conversely,anti-inflammatory Macrophage,anti-inflammatory phenotype(M2)macrophages contribute to tissue repair but may also promote fibrotic changes under prolonged metabolic stress.Pancreatic macrophages are activated under high-fat diet conditions,promoting inflammation and impairingβ-cell function through the SUCLA2-HIF-1αaxis and mechanistic Target of Rapamycin Complex 1(mTORC1)/PD-1 pathway,thereby establishing a self-perpetuating"metabolicimmunosuppressive"vicious cycle.Targeted intervention strategies against macrophages—such as SUCLA2 inhibitors can ameliorate metabolic dysregulation.Meanwhile,exosome-mediated interorgan communication[e.g.,via microRNA-155(miR-155)and miR-30a]offers novel insights for multi-system synergistic therapies.Understanding the mechanisms by which macrophages mediate metabolic dysregulation in the pancreas under obese conditions provides critical insights into the pathogenesis of obesity-related pancreatic disorders.展开更多
Automatic pancreas segmentation plays a pivotal role in assisting physicians with diagnosing pancreatic diseases,facilitating treatment evaluations,and designing surgical plans.Due to the pancreas’s tiny size,signifi...Automatic pancreas segmentation plays a pivotal role in assisting physicians with diagnosing pancreatic diseases,facilitating treatment evaluations,and designing surgical plans.Due to the pancreas’s tiny size,significant variability in shape and location,and low contrast with surrounding tissues,achieving high segmentation accuracy remains challenging.To improve segmentation precision,we propose a novel network utilizing EfficientNetV2 and multi-branch structures for automatically segmenting the pancreas fromCT images.Firstly,an EfficientNetV2 encoder is employed to extract complex and multi-level features,enhancing the model’s ability to capture the pancreas’s intricate morphology.Then,a residual multi-branch dilated attention(RMDA)module is designed to suppress irrelevant background noise and highlight useful pancreatic features.And re-parameterization Visual Geometry Group(RepVGG)blocks with amulti-branch structure are introduced in the decoder to effectively integrate deep features and low-level details,improving segmentation accuracy.Furthermore,we apply re-parameterization to the model,reducing computations and parameters while accelerating inference and reducing memory usage.Our approach achieves average dice similarity coefficient(DSC)of 85.59%,intersection over union(IoU)of 75.03%,precision of 85.09%,and recall of 86.57%on the NIH pancreas dataset.Compared with other methods,our model has fewer parameters and faster inference speed,demonstrating its enormous potential in practical applications of pancreatic segmentation.展开更多
Diffusion-weighted magnetic resonance imaging(DWI)has become an essential tool in the field of pancreatic magnetic resonance imaging,enabling the detection,characterization,prediction,and evaluation of pancreatic dise...Diffusion-weighted magnetic resonance imaging(DWI)has become an essential tool in the field of pancreatic magnetic resonance imaging,enabling the detection,characterization,prediction,and evaluation of pancreatic diseases.In this article,we review the acquisition parameters,postprocessing techniques,and quantitative methods utilized in pancreatic DWI.Various postprocessing models,including monoexponential,biexponential,stretched exponential and non-Gaussian kurtosis models,as well as deep learning networks,have been used to assess the clinical utility of these models in diagnosing pancreatic diseases.The single-shot echo-planar imaging sequence is the most commonly used sequence for DWI data acquisition in clinical settings,and the apparent diffusion coefficient(ADC)calculated using the monoexponential model is the most widely used quantitative parameter in clinical practice.The repeatability threshold for the ADC of a normal pancreas is 37%for test-retest scans,but the repeatability threshold for pancreatic tumors needs to be further investigated.Complex postprocessing models exploring novel DWI-based biomarkers beyond ADC to assess histological features,and artificial intelligence in DWI postprocessing and data analyses hold promise in the diagnosis of pancreatic diseases.Future work should focus on standardizing protocols,conducting multicentre studies,and exploring variety of methods to improve the accuracy of quantitative DWI results to increase the clinical effectiveness of DWI in patients with pancreatic diseases.展开更多
BACKGROUND Intraductal oncocytic papillary neoplasm(IOPN)of the pancreas is an extremely rare pancreatic tumor,with only sporadic cases reported in the literature.IOPN is difficult to diagnose and highly prone to misd...BACKGROUND Intraductal oncocytic papillary neoplasm(IOPN)of the pancreas is an extremely rare pancreatic tumor,with only sporadic cases reported in the literature.IOPN is difficult to diagnose and highly prone to misdiagnosis.IOPN carries a certain risk of progressing to invasive cancer.Surgical resection is the primary treatment for IOPN.According to the existing literature reports,the vast majority of patients with IOPN of the pancreas undergo open surgery,while only one case of laparoscopic surgery have been reported.CASE SUMMARY This report presents two cases of IOPN in elderly female patients,aged 60 and 61.Both patients were asymptomatic,and their pancreatic masses were discovered incidentally.Preoperative diagnosis of IOPN is challenging and prone to misdiagnosis.In the first case,the patient underwent a laparoscopic distal pancreatectomy and splenectomy.The surgical procedure spanned 342 minutes,with an estimated intraoperative blood loss of around 100 mL.The patient experienced an uneventful postoperative recovery and was discharged on the 8th postoperative day.For the second case,a laparoscopic pancreaticoduodenectomy was performed.The operation lasted for 431 minutes with an intraoperative blood loss of approximately 50 mL.The patient also demonstrated a favorable postoperative course and was discharged on the 24^(th)postoperative day.Postoperative pathology and immunohistochemistry confirmed the diagnosis of IOPN.No recurrence was observed in either patient after follow-up periods of 8 and 10 months,respectively.CONCLUSION These cases demonstrate that laparoscopic surgery can be considered as one of the treatment options for IOPN of the pancreas.展开更多
BACKGROUND Solid pseudopapillary neoplasm(SPN)of the pancreas is a rare epithelial tumor that primarily affects young women.Since the condition is often asymptomatic or presents with non-specific symptoms,its diagnosi...BACKGROUND Solid pseudopapillary neoplasm(SPN)of the pancreas is a rare epithelial tumor that primarily affects young women.Since the condition is often asymptomatic or presents with non-specific symptoms,its diagnosis can be difficult.CASE SUMMARY This report details the case of a 15-year-old girl who presented with a 2-year history of abdominal pain,with no significant findings during physical examination.Abdominal ultrasound revealed a well-defined heterogeneous solidcystic mass in the epigastric region,likely originating from the tail of the pancreas.A subsequent contrast-enhanced computed tomography scan indicated a welldefined cystic lesion with an enhancing solid component and capsule in the tail of the pancreas,suggestive of a cystic neoplasm.The patient underwent an open distal pancreatectomy with splenectomy,and histopathological analysis confirmed the diagnosis of SPN of the pancreas.CONCLUSION This case highlights the risk of SPN in adolescent girls and the necessity of early diagnosis and intervention for better outcomes.展开更多
BACKGROUND Malignant transformation of an ectopic pancreas is exceptionally rare,posing significant diagnostic challenges.As such,there are currently no established management guidelines.We present a rare case of gast...BACKGROUND Malignant transformation of an ectopic pancreas is exceptionally rare,posing significant diagnostic challenges.As such,there are currently no established management guidelines.We present a rare case of gastric adenocarcinoma arising from ectopic pancreatic tissue and provide a systematic review of previous case reports of adenocarcinomas derived from ectopic pancreas in the stomach,duodenum,and jejunum in the past 20 years.We provide an overview of the clinicopathological characteristics and discuss critical diagnostic and therapeutic considerations.CASE SUMMARY A 58-year-old female was admitted to our hospital in August 2024 due to elevated carbohydrate antigen 19-9.Relevant examinations found a huge abdominal tumor that was radiologically adherent to both the pancreatic head and the greater curvature of the gastric antrum.A preoperative endoscopic biopsy-confirmed adenocarcinoma,prompting a pancreaticoduodenectomy.Histopathological examination subsequently identified the tumor as an adenocarcinoma originating from a gastric ectopic pancreas.Adjuvant chemotherapy(gemcitabine+cap ecitabine)commenced on November 13,2024.After five cycles,surveillance imaging(April 3,2025)revealed metastatic progression,prompting a transition to second-line therapy(nab-paclitaxel+gemcitabine).The patient is currently undergoing regular chemotherapy and has been followed up regularly,and the condition has not changed significantly compared with before.CONCLUSION We hope that our findings will facilitate the clinical recognition of this entity and help to increase knowledge regarding its management.展开更多
Automatic pancreas segmentation in CT scans is crucial for various medical applications including early disease detection,treatment planning and therapeutic evaluation.However,the pancreas’s small size,irregular morp...Automatic pancreas segmentation in CT scans is crucial for various medical applications including early disease detection,treatment planning and therapeutic evaluation.However,the pancreas’s small size,irregular morphology,and low contrast with surrounding tissues make accurate pancreas segmentation still a challenging task.To address these challenges,we propose a novel RPMS-DSAUnet for accurate automatic pancreas segmentation in abdominal CT images.First,a Residual Pyramid Squeeze Attention module enabling hierarchical multi-resolution feature extraction with dynamic feature weighting and selective feature reinforcement capabilities is integrated into the backbone network,enhancing pancreatic feature extraction and improving localization accuracy.Second,a Multi-Scale Feature Extraction module is embedded into the network to expand the receptive field while preserving feature map resolution,mitigate feature degradation caused by network depth,and maintain awareness of pancreatic anatomical structures.Third,a Dimensional Squeeze Attention module is designed to reduce interference from adjacent organs and highlight useful pancreatic features through spatial-channel interaction,thereby enhancing sensitivity to small targets.Finally,a hybrid loss function combining Dice loss and Focal loss is employed to alleviate class imbalance issues.Extensive evaluation on two public datasets(NIH and MSD)shows that the proposed RPMS-DSAUnet achieves Dice Similarity Coefficients of 85.51%and 80.91%,with corresponding Intersection over Union(IoU)scores of 74.93%and 67.94%on each dataset,respectively.Experimental results demonstrate superior performance of the proposed model over baseline methods and state-of-the-art approaches,validating its effectiveness for CT-based pancreas segmentation.展开更多
文摘Diabetes is a widespread disease affecting millions of people,making it one of the leading causes of death in the world.It is a leading cause of cardiovascular disease and end-stage renal disease.Despite advancements in treatment,including insulin therapy and glucose monitoring devices,diabetes continues to significantly impact quality of life and current modalities do not reverse the end-organ damage associated with its progression.While traditionally indicated for type 1 diabetes,recent clinical practice refinements have made pancreas transplants available to select type 2 diabetics meeting specific criteria.These transplants are usually a part of a simultaneous kidney-pancreas transplant.However,although less frequently performed,transplants of pancreas alone or pancreas after kidney transplant are still available.For selected diabetic patients,pancreas transplants offer significant survival benefits and the improvement of cardiovascular and metabolic complications;however,they are not without risks.Complications such as bleeding,vascular thrombosis,infection,organ leak,and rejection are possible.Another challenge to pancreas transplantation is the decreasing number of procedures being performed due to decline in the volume of available highquality allografts and resource constraints of transplant centers.Advancements in monitoring and treatment of diabetes are contributing to the decline in pancreas transplants nowadays.
基金Supported by National Natural Science Foundation of China,No.82170651and the Research Support Fund of Hubei Microcirculation Society,No.HBWXH2024(1)-1.
文摘Intrapancreatic fat deposition(IPFD)has garnered increasing attention in recent years.The prevalence of IPFD is relatively high and associated with factors such as obesity,age,and sex.However,the pathophysiological mechanisms underlying IPFD remain unclear,with several potential contributing factors,including oxida-tive stress,alterations in the gut microbiota,and hormonal imbalances.IPFD was found to be highly correlated with the occurrence and prognosis of exocrine pan-creatic diseases.Although imaging techniques remain the primary diagnostic approach for IPFD,an expanding array of biomarkers and clinical scoring systems have been identified for screening purposes.Currently,effective treatments for IPFD are not available;however,existing medications,such as glucagon-like peptide-1 receptor agonists,and new therapeutic approaches explored in animal models have shown considerable potential for managing this disease.This paper reviews the pathogenesis of IPFD,its association with exocrine pancreatic disea-ses,and recent advancements in its diagnosis and treatment,emphasizing the significant clinical relevance of IPFD.
文摘BACKGROUND: The good therapeutic effects of large dose of dexamethasone on severe acute pancreatitis (SAP) patients have been proved. This study was designed to investigate the influence of dexamethasone on apoptosis of acinar cells in the pancreas of rats with SAP and the protein expression of the apoptosis-regulating genes Bax and Bcl-2. METHODS: Ninety Sprague-Dawley rats with SAP were randomly divided into a model group and a dexamethasone treated group (45 rats in each group), and another 45 rats formed the sham operation group. Survival rates were calculated and gross pathological changes in the pancreas of each group were observed under a light microscope 3, 6 and 12 hours after operation. Tissue microarray technology was applied to prepare pancreatic tissue sections. The changes in Bax and Bcl-2 protein expression levels of pancreatic tissues from each group were assessed by immunohistochemical staining, and TUNEL staining was used to evaluate changes in apoptosis index. RESULTS: The model and treated groups did not differ in mortality at each time point. The pathological score for the pancreas in the treated group was significantly lower than that in the model group at 3 and 6 hours. The positive rates of Bax protein expression in the head and tail of the pancreas in the treated group at all time points were all markedly higher than those of the model group. The positive rate of Bcl-2 protein expression in the head of the pancreas in the treated group was significantly higher than that of the model group at 3 hours. TUNEL staining showed that the pancreas head and tail apoptosis indices of the treated group were markedly higher than those of the model group after 6 hours. CONCLUSIONS: Apoptosis may be a protective response. to pancreatic cell injury. The mechanism of action of dexamethasone in treating SAP may be related to the apoptosis of acinar cells in the pancreas induced by apoptosis-regulating genes such as Bax and Bcl-2. The advantages of tissue microarrays in pathological examination of the pancreas include saving of time and energy, efficiency and highly representative.
文摘Giant cell tumors of the pancreas come in three varieties-osteoclastic,pleomorphic,and mixed histology.These tumors have distinctive endoscopic,clinical,and cytological features.Giant cell tumors have a controversial histogenesis,with some authors favoring an epithelial origin and others favoring a mesenchymal origin.The true origin of these lesions remains unclear at this time.These are also very rare tumors but proper identification and differentiation from more common pancreatic adenocarcinoma is important.The risk factors of these tumors and the prognosis may be different from those associated with standard pancreatic adenocarcinoma.Recognition of these differences can significantly affect patient care.These lesions have a unique appearance when imaged with endoscopic ultrasound(EUS),and these lesions can be diagnosed via EUS guided Fine Needle Aspiration(FNA).This manuscript will review the endoscopic,clinical,and pathologic features of these tumors.
文摘BACKGROUND: Giant cell tumors are rare and highly malignant tumors of the pancreas. Based on two distinct cell populations, they have been divided into two subtypes corresponding to the osteoclast-like giant cell tumor and the pleomorphic giant cell carcinoma of the pancreas. Distinctive imaging features of the tumors remain uncharacterized. Surgical removal is the only appropriate treatment for them, but responses to chemotherapy or radiotherapy remain undocumented. METHODS: Clinical, radiological, histopathologic, and immuno- histochemical features of two cases of giant cell tumor of the pancreas are presented along with a brief review of the literature. RESULTS: En-bloc resection was done successfully in both cases. The patient with an osteoclast-like giant cell tumor remained disease-free with no clinical or radiological evidence of recurrence at 6 months after surgery. However, the patient with the pleomorphic type died 4 months later due to diffuse pulmonary metastasis. CONCLUSIONS: En-bloc surgical resection is the only appropriate treatment for giant cell tumors. The overall prognosis of these tumors is poorer than that of pancreatic ductal adenocarcinoma, especially the pleomorphic type. More studies are required to document the management and outcomes of the tumors.
文摘Since the first description of intraductal papillary mucinous neoplasms(IPMNs)of the pancreas in the eighties,their identification has dramatically increased in the last decades,hand to hand with the improvements in diagnostic imaging and sampling techniques for the study of pancreatic diseases.However,the heterogeneity of IPMNs and their malignant potential make difficult the management of these lesions.The objective of this review is to identify the molecular characteristics of IPMNs in order to recognize potential markers for the discrimination of more aggressive IPMNs requiring surgical resection from benign IPMNs that could be observed.We briefly summarize recent research findings on the genetics and epigenetics of intraductal papillary mucinous neoplasms,identifying some genes,molecular mechanisms and cellular signaling pathways correlated to the pathogenesis of IPMNs and their progression to malignancy.The knowledge of molecular biology of IPMNs has impressively developed over the last few years.A great amount of genes functioning as oncogenes or tumor suppressor genes have been identified,in pancreatic juice or in blood or in the samples from the pancreatic resections,but further researches are required to use these informations for clinical intent,in order to better define the natural history of these diseases and to improve their management.
文摘Objective:To evaluate the consequence of oral administration of Calliandra portoricensis(C. portoricensis) leaf extract on the stomach and pancreas in Swiss albino mice.Methods:Three, groups of mice(B,C and D) were treated with 4 mg/kg of C.portoricensis extract.Croup A was the control and received an equivalent volume of distilled water.Group B received C.portoricensis leaf extract for 7 days.Croup C received C.portoricensis leaf extract for 14 days,and Croup D received C.portoricensis leaf extract for 28 days.At different stages in the study,the mice were sacrificed and the stomach and pancreas were excised and fixed in 10%formol saline for histological analysis.Results:The result showed a normal microstructural outline in groups B and C as compared with the control.However,animals in group D showed disorganization of the mucosa and discontinuation of epithelial lining of the stomach while the islets of Langerans in the pancreas were at various degree of degeneration as compared with the control mice. Conclusions:The present finding suggests that chronic administration(28 days as seen in this study) of C.portoricensis leaf extract may inhibit the proper function of the stomach and pancreas.
文摘Intraductal papillary-mucinous neoplasm(IPMN) of the pancreas is a clinically and morphologically distinctive precursor lesion of pancreatic cancer,characterized by gradual progression through a sequence of neoplastic changes.Based on the nature of the constituting neoplastic epithelium,degree of dysplasia and location within the pancreatic duct system,IPMNs are divided in several types which differ in their biological properties and clinical outcome.Molecular analysis and recent animal studies suggest that IPMNs develop in the context of a field-defect and reveal their possible relationship with other neoplastic precursor lesions of pancreatic cancer.
文摘AIM: To report the clinicopathological features and magnetic resonance imaging (MRI) findings of solid and pseudopapillary tumor (SPT) of pancreas.METHODS: From 1981 to 2005, 26 surgically treated cases of SPT were retrospectively reviewed. MRI findings of the latest 11 consecutive SPT cases were investigated.RESULTS: There were 25 women and one man having SPT (median age: 23 year) with a median tumor size of 7.5 cm. Among them, nine patients developed solid pseudopapillary carcinoma. During the median follow-up period of 66 mo, the 5-year survival rate of the 26 SPT patients was 96.2%. Three MRI features were proposed including Type 1 image, displaying SPT with completely solid part. All SPT patients with type 1 image were detected incidentally. Type 2 image displays of SPT with solid mass hemorrhage and type 3 image with massive hemorrhage. All the eight SPT patients with type 2 and 3 images suffered abdominal pain due to hemorrhage from SPT.CONCLUSION: SPT had a favorable survival rate irrespective of surgical procedures, malignancy, and MRI findings, however, MRI could reliably correlate with its clinicopathological features.
文摘Objective:To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas(SPTP). Methods:Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin(HE) staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results:Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin(9/9 cases), AAT(9/9 cases), NSE(9/9 cases), ACT(7/9 cases), CK20(2/9 cases), CgA(1/9 cases), S-100(3/gcases), PR(4/gcases), Syn(3/9 cases) and CD56(5/9cases), negative in CEA and ER. Conclusion:SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.
文摘Recently, a novel and distinct pancreatic cystic tumor termed 'mudnous nonneoplastic' cyst was described in the literature. We report our experience with a 71-year-old female with a cystic tumor in the body of the pancreas demonstrating features suggestive of this diagnosis. We also review the literature regarding this 'novel' pathological entity and discuss critically its existence and its differential diagnoses.
文摘BACKGROUND A solitary fibrous tumor(SFT)is often located in the pleura,while SFT of the pancreas is extremely rare.Here,we report a case of SFT of the pancreas and discuss imaging,histopathology,and immunohistochemistry for accurate diagnosis and treatment.CASE SUMMARY A 54-year-old man presented to our hospital with pancreatic occupancy for over a month.There were no previous complaints of discomfort.His blood pressure was normal.Blood glucose,tumor markers,and enhanced computed tomography(CT)suggested a malignant tumor.Because the CT appearance of pancreatic cancer varies,we could not confirm the diagnosis;therefore,we performed endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB).Pathology and immunohistochemistry were consistent with SFT of the pancreas.The posto-perative pathology and immunohistochemistry were consistent with the puncture results.The patient presented for a follow-up examination one month after discharge with no adverse effects.CONCLUSION Other diseases must be excluded in patients with a pancreatic mass that cannot be diagnosed.CT and pathological histology have diagnostic value for pancreatic tumors.Endoscopic puncture biopsy under ultrasound can help diagnose pancreatic masses that cannot be diagnosed preoperatively.Surgery is an effective treatment for SFT of the pancreas;however,long-term follow-up is strongly recommended because of the possibility of malignant transformation of the tumor.
基金supported by the National Cancer Institute(T32,CA 236621-5).
文摘Annular pancreas is a rare congenital anomaly formed by a thin band of pancreatic tissue that encircles the descending duodenum and leads to partial or complete obstruction.Annular pancreas is estimated to occur in less than 5/100,000 people;however,the true incidence is unknown given that annular pancreas is frequently asymptomatic and only an incidental finding on cross-sectional imaging or autopsy examination.1,2 When symptomatic,patients typically present with abdominal pain,nausea and vomiting,or postprandial fullness due to gastric outlet obstruction.3 Other and less common presentations include peptic ulcer disease,biliary obstruction,or symptoms of acute or chronic pancreatitis.
基金Supported by National Natural Science Foundation of China Youth Science Fund Project,No.82305376the Young Talent Support Program of the China Association for Acupuncture-Moxibustion,No.2024-2026ZGZJXH-QNRC005+1 种基金the 2024 Jiangsu Provincial Young Scientific and Technological Talent Support Program,No.JSTJ-2024-380the 2025 Jiangsu Science and Technology Think Tank Program Project,No.JSKX0125035。
文摘Obesity is a major contributor to metabolic dysfunction,and its impact on pancreatic health has garnered increasing attention.Macrophages,as key regulators of inflammation and metabolism,play a central role in mediating obesity-induced pancreatic damage.In obese individuals,excessive lipid accumulation and chronic low-grade inflammation drive the infiltration and polarization of macrophages within the pancreas.These macrophages,particularly the pro-inflammatory Macrophage,pro-inflammatory phenotype(M1)phenotype,secrete cytokines such as C-C motif ligand 2(CCL2)and transforming growth factor beta(TGF-β),which disrupt pancreaticβ-cell function and impair insulin secretion.Conversely,anti-inflammatory Macrophage,anti-inflammatory phenotype(M2)macrophages contribute to tissue repair but may also promote fibrotic changes under prolonged metabolic stress.Pancreatic macrophages are activated under high-fat diet conditions,promoting inflammation and impairingβ-cell function through the SUCLA2-HIF-1αaxis and mechanistic Target of Rapamycin Complex 1(mTORC1)/PD-1 pathway,thereby establishing a self-perpetuating"metabolicimmunosuppressive"vicious cycle.Targeted intervention strategies against macrophages—such as SUCLA2 inhibitors can ameliorate metabolic dysregulation.Meanwhile,exosome-mediated interorgan communication[e.g.,via microRNA-155(miR-155)and miR-30a]offers novel insights for multi-system synergistic therapies.Understanding the mechanisms by which macrophages mediate metabolic dysregulation in the pancreas under obese conditions provides critical insights into the pathogenesis of obesity-related pancreatic disorders.
基金supported by the Science and Technology Innovation Programof Hunan Province(Grant No.2022RC1021)the Hunan Provincial Natural Science Foundation Project(Grant No.2023JJ60124)+1 种基金the Changsha Natural Science Foundation Project(Grant No.kq2202265)the key project of the Hunan Provincial of Education(Grant No.22A0255).
文摘Automatic pancreas segmentation plays a pivotal role in assisting physicians with diagnosing pancreatic diseases,facilitating treatment evaluations,and designing surgical plans.Due to the pancreas’s tiny size,significant variability in shape and location,and low contrast with surrounding tissues,achieving high segmentation accuracy remains challenging.To improve segmentation precision,we propose a novel network utilizing EfficientNetV2 and multi-branch structures for automatically segmenting the pancreas fromCT images.Firstly,an EfficientNetV2 encoder is employed to extract complex and multi-level features,enhancing the model’s ability to capture the pancreas’s intricate morphology.Then,a residual multi-branch dilated attention(RMDA)module is designed to suppress irrelevant background noise and highlight useful pancreatic features.And re-parameterization Visual Geometry Group(RepVGG)blocks with amulti-branch structure are introduced in the decoder to effectively integrate deep features and low-level details,improving segmentation accuracy.Furthermore,we apply re-parameterization to the model,reducing computations and parameters while accelerating inference and reducing memory usage.Our approach achieves average dice similarity coefficient(DSC)of 85.59%,intersection over union(IoU)of 75.03%,precision of 85.09%,and recall of 86.57%on the NIH pancreas dataset.Compared with other methods,our model has fewer parameters and faster inference speed,demonstrating its enormous potential in practical applications of pancreatic segmentation.
基金Supported by National Natural Science Foundation of China,No.62472315Shanghai Science and Technology Innovation Action Plan Medical Innovation Research Project,No.20Y11912500.
文摘Diffusion-weighted magnetic resonance imaging(DWI)has become an essential tool in the field of pancreatic magnetic resonance imaging,enabling the detection,characterization,prediction,and evaluation of pancreatic diseases.In this article,we review the acquisition parameters,postprocessing techniques,and quantitative methods utilized in pancreatic DWI.Various postprocessing models,including monoexponential,biexponential,stretched exponential and non-Gaussian kurtosis models,as well as deep learning networks,have been used to assess the clinical utility of these models in diagnosing pancreatic diseases.The single-shot echo-planar imaging sequence is the most commonly used sequence for DWI data acquisition in clinical settings,and the apparent diffusion coefficient(ADC)calculated using the monoexponential model is the most widely used quantitative parameter in clinical practice.The repeatability threshold for the ADC of a normal pancreas is 37%for test-retest scans,but the repeatability threshold for pancreatic tumors needs to be further investigated.Complex postprocessing models exploring novel DWI-based biomarkers beyond ADC to assess histological features,and artificial intelligence in DWI postprocessing and data analyses hold promise in the diagnosis of pancreatic diseases.Future work should focus on standardizing protocols,conducting multicentre studies,and exploring variety of methods to improve the accuracy of quantitative DWI results to increase the clinical effectiveness of DWI in patients with pancreatic diseases.
基金Supported by the Zhejiang Medical Science and Technology Project,No.2022KY1325 and No.2023KY381.
文摘BACKGROUND Intraductal oncocytic papillary neoplasm(IOPN)of the pancreas is an extremely rare pancreatic tumor,with only sporadic cases reported in the literature.IOPN is difficult to diagnose and highly prone to misdiagnosis.IOPN carries a certain risk of progressing to invasive cancer.Surgical resection is the primary treatment for IOPN.According to the existing literature reports,the vast majority of patients with IOPN of the pancreas undergo open surgery,while only one case of laparoscopic surgery have been reported.CASE SUMMARY This report presents two cases of IOPN in elderly female patients,aged 60 and 61.Both patients were asymptomatic,and their pancreatic masses were discovered incidentally.Preoperative diagnosis of IOPN is challenging and prone to misdiagnosis.In the first case,the patient underwent a laparoscopic distal pancreatectomy and splenectomy.The surgical procedure spanned 342 minutes,with an estimated intraoperative blood loss of around 100 mL.The patient experienced an uneventful postoperative recovery and was discharged on the 8th postoperative day.For the second case,a laparoscopic pancreaticoduodenectomy was performed.The operation lasted for 431 minutes with an intraoperative blood loss of approximately 50 mL.The patient also demonstrated a favorable postoperative course and was discharged on the 24^(th)postoperative day.Postoperative pathology and immunohistochemistry confirmed the diagnosis of IOPN.No recurrence was observed in either patient after follow-up periods of 8 and 10 months,respectively.CONCLUSION These cases demonstrate that laparoscopic surgery can be considered as one of the treatment options for IOPN of the pancreas.
文摘BACKGROUND Solid pseudopapillary neoplasm(SPN)of the pancreas is a rare epithelial tumor that primarily affects young women.Since the condition is often asymptomatic or presents with non-specific symptoms,its diagnosis can be difficult.CASE SUMMARY This report details the case of a 15-year-old girl who presented with a 2-year history of abdominal pain,with no significant findings during physical examination.Abdominal ultrasound revealed a well-defined heterogeneous solidcystic mass in the epigastric region,likely originating from the tail of the pancreas.A subsequent contrast-enhanced computed tomography scan indicated a welldefined cystic lesion with an enhancing solid component and capsule in the tail of the pancreas,suggestive of a cystic neoplasm.The patient underwent an open distal pancreatectomy with splenectomy,and histopathological analysis confirmed the diagnosis of SPN of the pancreas.CONCLUSION This case highlights the risk of SPN in adolescent girls and the necessity of early diagnosis and intervention for better outcomes.
基金Supported by Hygiene and Health Development Scientific Research Fostering Plan of Haidian District Beijing,No.HP2024-19-503002National Key R&D Program of China,No.2023YFC2413802Beijing Municipal Administration of Hospitals Incubating Program,No.PX2024041.
文摘BACKGROUND Malignant transformation of an ectopic pancreas is exceptionally rare,posing significant diagnostic challenges.As such,there are currently no established management guidelines.We present a rare case of gastric adenocarcinoma arising from ectopic pancreatic tissue and provide a systematic review of previous case reports of adenocarcinomas derived from ectopic pancreas in the stomach,duodenum,and jejunum in the past 20 years.We provide an overview of the clinicopathological characteristics and discuss critical diagnostic and therapeutic considerations.CASE SUMMARY A 58-year-old female was admitted to our hospital in August 2024 due to elevated carbohydrate antigen 19-9.Relevant examinations found a huge abdominal tumor that was radiologically adherent to both the pancreatic head and the greater curvature of the gastric antrum.A preoperative endoscopic biopsy-confirmed adenocarcinoma,prompting a pancreaticoduodenectomy.Histopathological examination subsequently identified the tumor as an adenocarcinoma originating from a gastric ectopic pancreas.Adjuvant chemotherapy(gemcitabine+cap ecitabine)commenced on November 13,2024.After five cycles,surveillance imaging(April 3,2025)revealed metastatic progression,prompting a transition to second-line therapy(nab-paclitaxel+gemcitabine).The patient is currently undergoing regular chemotherapy and has been followed up regularly,and the condition has not changed significantly compared with before.CONCLUSION We hope that our findings will facilitate the clinical recognition of this entity and help to increase knowledge regarding its management.
基金supported by the National Natural and Science Foundation of China under Grant No.12301662Zhejiang Provincial Natural Science Foundation of China under Grant No.LQ21F030019.
文摘Automatic pancreas segmentation in CT scans is crucial for various medical applications including early disease detection,treatment planning and therapeutic evaluation.However,the pancreas’s small size,irregular morphology,and low contrast with surrounding tissues make accurate pancreas segmentation still a challenging task.To address these challenges,we propose a novel RPMS-DSAUnet for accurate automatic pancreas segmentation in abdominal CT images.First,a Residual Pyramid Squeeze Attention module enabling hierarchical multi-resolution feature extraction with dynamic feature weighting and selective feature reinforcement capabilities is integrated into the backbone network,enhancing pancreatic feature extraction and improving localization accuracy.Second,a Multi-Scale Feature Extraction module is embedded into the network to expand the receptive field while preserving feature map resolution,mitigate feature degradation caused by network depth,and maintain awareness of pancreatic anatomical structures.Third,a Dimensional Squeeze Attention module is designed to reduce interference from adjacent organs and highlight useful pancreatic features through spatial-channel interaction,thereby enhancing sensitivity to small targets.Finally,a hybrid loss function combining Dice loss and Focal loss is employed to alleviate class imbalance issues.Extensive evaluation on two public datasets(NIH and MSD)shows that the proposed RPMS-DSAUnet achieves Dice Similarity Coefficients of 85.51%and 80.91%,with corresponding Intersection over Union(IoU)scores of 74.93%and 67.94%on each dataset,respectively.Experimental results demonstrate superior performance of the proposed model over baseline methods and state-of-the-art approaches,validating its effectiveness for CT-based pancreas segmentation.