We revisit the issue of whether the effective potential for the conformal factor of the metric,which is generated by quantized matter fields,possesses a non-vanishing vacuum expectation value(VEV)or not.We prove that ...We revisit the issue of whether the effective potential for the conformal factor of the metric,which is generated by quantized matter fields,possesses a non-vanishing vacuum expectation value(VEV)or not.We prove that the effective potential has a vanishing vacuum expectation value on the basis of a global GL(4)symmetry.We also account for why there seems to be two different effective potentials for the conformal factor in a theory,one of which gives rise to a vanishing VEV for the conformal factor,whereas the other has a non-vanishing VEV.展开更多
AIM: To identify the actual clinical management and associated factors of delayed perforation after gastric endoscopic submucosal dissection(ESD).METHODS: A total of 4943 early gastric cancer(EGC) patients underwent E...AIM: To identify the actual clinical management and associated factors of delayed perforation after gastric endoscopic submucosal dissection(ESD).METHODS: A total of 4943 early gastric cancer(EGC) patients underwent ESD at our hospital between January 1999 and June 2012. We retrospectively assessed the actual management of delayed perforation. In addition, to determine the factors associated with delayed perforation, after excluding 123 EGC patients with perforations that occurred during the ESD procedure, we analyzed the following clinicopathological factors among the remaining 4820 EGC patients by comparing the ESD cases with delayed perforation and the ESD cases without perforation: age, sex, chronological periods, clinical indications for ESD, status of the stomach, location, gastric circumference, tumor size, invasion depth, presence/absence of ulceration, histological type, type of resection, and procedure time.RESULTS: Delayed perforation occurred in 7(0.1%) cases. The median time until the occurrence of delayed perforation was 11 h(range, 6-172 h). Three(43%) of the 7 cases required emergency surgery, while four were conservatively managed without surgical intervention. Among the 4 cases with conservative management, 2 were successfully managed endoscopically using the endoloop-endoclip technique. The median hospital stay was 18 d(range, 15-45 d). There were no delayed perforation-related deaths. Based on a multivariate analysis, gastric tube cases(OR = 11.0; 95%CI: 1.7-73.3; P = 0.013) were significantly associated with delayed perforation.CONCLUSION: Endoscopists must be aware of not only the identified factors associated with delayed perforation, but also how to treat this complicationeffectively and promptly.展开更多
Endoscopic ultrasound (EUS) devices were first designed and manufactured more than 30 years ago, and since then investigators have reported EUS is effective for determining both the staging and the depth of invasion o...Endoscopic ultrasound (EUS) devices were first designed and manufactured more than 30 years ago, and since then investigators have reported EUS is effective for determining both the staging and the depth of invasion of esophageal and gastric cancers. We review the present status, the methods, and the findings of EUS when used to diagnose and stage early esophageal and gastric cancer. EUS using high-frequency ultrasound probes is more accurate than conventional EUS for the evaluation of the depth of invasion of superficial esophageal carcinoma. The rates of accurate evaluation of the depth of invasion by EUS using high-frequency ultrasound probes were 70%-88% for intramucosal cancer, and 83%-94% for submucosal invasive cancer. But the sensitivity of EUS using high-frequency ultrasound probes for the diagnosis of submucosal invasive cancer was relatively low, making it difficult to confirm minute submucosal invasion. The accuracy of EUS using high-frequency ultrasound probes for early gastric tumor classification can be up to 80% compared with 63% for conventional EUS, although the accuracy of EUS using high-frequency ultrasound probes relatively decreases for those patients with depressed-type lesions, undifferentiated cancer, concomitant ulceration, expanded indications, type 0-I?lesions, and lesions located in the upper-third of the stomach. A 92% overall accuracy rate was achieved when both the endoscopic appearance and the findings from EUS using high-frequency ultrasound probes were considered together for tumor classification. Although EUS using high-frequency ultrasound probes has limitations, it has a high depth of invasion accuracy and is a useful procedure to distinguish lesions in the esophagus and stomach that are indicated for endoscopic resection.展开更多
AIM: To assess the diagnostic concordance between endoscopic and histological atrophy in the United Kingdom and Japan.METHODS: Using published data,a total of 252 patients,126 in the United Kingdom and 126 in Japan,ag...AIM: To assess the diagnostic concordance between endoscopic and histological atrophy in the United Kingdom and Japan.METHODS: Using published data,a total of 252 patients,126 in the United Kingdom and 126 in Japan,aged 20 to 80 years,were evaluated. The extent of endoscopic atrophy was classified into five subgroups according to a modified Kimura-Takemoto classification system and was compared with histological findings of atrophy at five biopsy sites according to the updated Sydney system.RESULTS: The strength of agreement of the extent of atrophy between histology and visual endoscopic inspection showed good reproducibili ty,wi th a weighted kappa value of 0.76(P < 0.001). Multivariate analysis showed that three factors were associated with decreased concordance: Japanese ethnicity [odds ratio(OR) 0.22,95% confidence interval(CI) 0.11-0.43],older age(OR = 0.32,95%CI: 0.16-0.66) and endoscopic atrophy(OR = 0.10,95%CI: 0.03-0.36). The strength of agreement between endoscopic and histological atrophy,assessed by cancer risk-oriented grading,was reproducible,with a kappa value of 0.81(95%CI: 0.75-0.87). Only nine patients(3.6%) were endoscopically underdiagnosed with antral predominant rather than extensive atrophy and were considered false negatives.CONCLUSION: Endoscopic grading can predict histological atrophy with few false negatives,indicating that precancerous conditions can be identified during screening endoscopy,particularly in patients in western countries.展开更多
Gastric perforation is one of the most serious complications that can occur during endoscopic submucosal dissection(ESD).In terms of the treatment of such perforations,we previously reported that perforations immediat...Gastric perforation is one of the most serious complications that can occur during endoscopic submucosal dissection(ESD).In terms of the treatment of such perforations,we previously reported that perforations immediately observed and successfully closed with endoclips during endoscopic resection could be managed conservatively.We now report the first case in our medical facility of a gastric perforation during ESD that was ineffectively treated conservatively even after successful endoscopic closure.In December 2006,we performed ESD on a recurrent early gastric cancer in an 81-year-old man with a medical history of laparotomy for cholelithiasis.A perforation occurred during ESD that was immediately observed and successfully closed with endoclips so that ESD could be continued resulting in an en-bloc resection.Intensive conservative management was conducted following ESD,however,an endoscopic examination five days after ESD revealed dehiscence of the perforation requiring an emergency laparotomy.展开更多
A 67-year-old male underwent endoscopic submucosal dissection(ESD)to treat early gastric cancer(EGC)in 2001.The lesion(50 mm × 25 mm diameter)was histologically diagnosed as poorly differentiated adenocarcinoma,w...A 67-year-old male underwent endoscopic submucosal dissection(ESD)to treat early gastric cancer(EGC)in 2001.The lesion(50 mm × 25 mm diameter)was histologically diagnosed as poorly differentiated adenocarcinoma,with an ulcer finding.Although the tumor was confined to the mucosa with no evidence of lymphovascular involvement,the ESD was regarded as a noncurative resection due to the histological type,tumor size,and existence of an ulcer finding(as indicated by the 2010 Japanese gastric cancer treatment guidelines,ver.3).Despite strong recommendation for subsequent gastrectomy,the patient refused surgery.An alternative follow-up routine was designed,which included five years of biannual clinical examinations to detect and measure serum tumor markers and perform visual assessment of recurrence by endoscopy and computed tomography scan after which the examinations were performed annually.The patient's condition remained stable for eight years,until a complaint of back pain in 2010 prompted further clinical investigation.Bone scintigraphy indicated increased uptake.Histological examination of biopsy specimens taken from the lumbar spine revealed adenocarcinoma resembling the carcinoma cells from the EGC that had been treated previously by ESD,and which was consistent with immunohistochemical findings of gastrointestinal tract cancer.Thus,the diagnosis of bone metastasis from EGC was made.The reported rates of EGC recurrence in surgically resected cases range 1.4%-3.4%,but among these bone metastasis is very rare.To our knowledge,this is the first reported case of bone metastasis from EGC following a non-curative ESD and occurring after an eight-year disease-free interval.展开更多
It has been reported recently that small undifferentiated intramucosal early gastric cancer(EGC) < 20 mm in size without any lymphovascular involvement or ulcerative findings had virtually no risk of lymph-node(LN)...It has been reported recently that small undifferentiated intramucosal early gastric cancer(EGC) < 20 mm in size without any lymphovascular involvement or ulcerative findings had virtually no risk of lymph-node(LN) metastasis.Consequently,the indications for endoscopic resection were expanded to include such undifferentiated EGC lesions.We describe herein a case of a small undifferentiated intramucosal EGC < 20 mm in size without lymphovascular involvement or ulcerative findings that involved lymph-node metastasis.A 57-year-old female underwent pylorus preserving gastrectomy as standard treatment for an undifferentiated EGC 15 mm in size without any ulcerative finding.The surgical specimen revealed a signet-ring cell carcinoma with a moderately to poorly differentiated adenocarcinoma limited to the mucosa that was 15 mm in size with no lymphovascular involvement or ulcerative findings.This case involved LN metastasis,however,and the lesion was diagnosed as pathological stage ⅡA(T1N2M0) according to the Japanese Classification of Gastric Carcinoma.展开更多
An 80-year-old man was under annual surveillance esophagogastroduodenoscopy after endoscopic submucosal dissection(ESD) for early gastric cancer(EGC).Two years after the initial ESD, a 0-Ⅱc type metachronous EGC lesi...An 80-year-old man was under annual surveillance esophagogastroduodenoscopy after endoscopic submucosal dissection(ESD) for early gastric cancer(EGC).Two years after the initial ESD, a 0-Ⅱc type metachronous EGC lesion, 8 mm in size, without an ulcer scar, was found in the gastric antrum.The estimated tumor depth was up to the mucosa, and biopsy revealed well and poorly differentiated adenocarcinoma.ESD was performed for this lesion and en bloc resection with negative margins was achieved.Histopathological examination revealed an adenosquamous carcinoma 8 mm in size invading the deep submucosal layer(1600 μm), with lymphovascular invasion, consistent with the diagnosis of non-curative resection.Additional gastrectomy was recommended for this patient; however, two months after the ESD, preoperative computed tomography revealed multiple liver metastases, and the patient was considered as an unsuitable candidate for surgical resection.Systemic chemotherapy was therefore started; however, the patient died of gastric cancer 27 mo after the second ESD.Early gastric adenosquamous carcinoma localized to the mucosa and submucosa is extremely rare and its clinical behavior is not well known.The present report is very significant in that it underscores the distinct possibility of gastric adenosquamous carcinoma being very aggressive and fatal even when detected at an early cancer.展开更多
AIM: To evaluate the determination of the margin of differentiated-type early gastric cancers by using conventional endoscopy.METHODS: We retrospectively evaluated 364 differentiated early gastric cancers that were en...AIM: To evaluate the determination of the margin of differentiated-type early gastric cancers by using conventional endoscopy.METHODS: We retrospectively evaluated 364 differentiated early gastric cancers that were endoscopically resected as en-bloc specimens and diagnosed pathologically in detail between November 2007 and October 2008. All procedures were done with conventional endoscopes and all endoscopic samples, before and after indigo carmine dye, were re-evaluated using a digital filing system by one endoscopist. We analyzed the incidence of lesions with unclear margins and the relationship between unclear margins and relevant clinicopathological findings. RESULTS: The rate of lesions with unclear margins was 20.6%(75/364). Multivariate regression analysis suggested that the factors that make the determination of the margin difficult were normal color, presence of components of flat area(0-IIb), a diameter ≥ 21 mm, ulceration, and components of poorly differentiated adenocarcinoma in the mucosal surface.CONCLUSION: As many as 20% of differentiated early gastric cancers show unclear margins. Consideration of the factors associated with unclear margins may help endoscopists to accurately determine the margins of the lesion.展开更多
基金supported in part by the JSPS Kakenhi under Grant No.21K03539。
文摘We revisit the issue of whether the effective potential for the conformal factor of the metric,which is generated by quantized matter fields,possesses a non-vanishing vacuum expectation value(VEV)or not.We prove that the effective potential has a vanishing vacuum expectation value on the basis of a global GL(4)symmetry.We also account for why there seems to be two different effective potentials for the conformal factor in a theory,one of which gives rise to a vanishing VEV for the conformal factor,whereas the other has a non-vanishing VEV.
文摘AIM: To identify the actual clinical management and associated factors of delayed perforation after gastric endoscopic submucosal dissection(ESD).METHODS: A total of 4943 early gastric cancer(EGC) patients underwent ESD at our hospital between January 1999 and June 2012. We retrospectively assessed the actual management of delayed perforation. In addition, to determine the factors associated with delayed perforation, after excluding 123 EGC patients with perforations that occurred during the ESD procedure, we analyzed the following clinicopathological factors among the remaining 4820 EGC patients by comparing the ESD cases with delayed perforation and the ESD cases without perforation: age, sex, chronological periods, clinical indications for ESD, status of the stomach, location, gastric circumference, tumor size, invasion depth, presence/absence of ulceration, histological type, type of resection, and procedure time.RESULTS: Delayed perforation occurred in 7(0.1%) cases. The median time until the occurrence of delayed perforation was 11 h(range, 6-172 h). Three(43%) of the 7 cases required emergency surgery, while four were conservatively managed without surgical intervention. Among the 4 cases with conservative management, 2 were successfully managed endoscopically using the endoloop-endoclip technique. The median hospital stay was 18 d(range, 15-45 d). There were no delayed perforation-related deaths. Based on a multivariate analysis, gastric tube cases(OR = 11.0; 95%CI: 1.7-73.3; P = 0.013) were significantly associated with delayed perforation.CONCLUSION: Endoscopists must be aware of not only the identified factors associated with delayed perforation, but also how to treat this complicationeffectively and promptly.
文摘Endoscopic ultrasound (EUS) devices were first designed and manufactured more than 30 years ago, and since then investigators have reported EUS is effective for determining both the staging and the depth of invasion of esophageal and gastric cancers. We review the present status, the methods, and the findings of EUS when used to diagnose and stage early esophageal and gastric cancer. EUS using high-frequency ultrasound probes is more accurate than conventional EUS for the evaluation of the depth of invasion of superficial esophageal carcinoma. The rates of accurate evaluation of the depth of invasion by EUS using high-frequency ultrasound probes were 70%-88% for intramucosal cancer, and 83%-94% for submucosal invasive cancer. But the sensitivity of EUS using high-frequency ultrasound probes for the diagnosis of submucosal invasive cancer was relatively low, making it difficult to confirm minute submucosal invasion. The accuracy of EUS using high-frequency ultrasound probes for early gastric tumor classification can be up to 80% compared with 63% for conventional EUS, although the accuracy of EUS using high-frequency ultrasound probes relatively decreases for those patients with depressed-type lesions, undifferentiated cancer, concomitant ulceration, expanded indications, type 0-I?lesions, and lesions located in the upper-third of the stomach. A 92% overall accuracy rate was achieved when both the endoscopic appearance and the findings from EUS using high-frequency ultrasound probes were considered together for tumor classification. Although EUS using high-frequency ultrasound probes has limitations, it has a high depth of invasion accuracy and is a useful procedure to distinguish lesions in the esophagus and stomach that are indicated for endoscopic resection.
文摘AIM: To assess the diagnostic concordance between endoscopic and histological atrophy in the United Kingdom and Japan.METHODS: Using published data,a total of 252 patients,126 in the United Kingdom and 126 in Japan,aged 20 to 80 years,were evaluated. The extent of endoscopic atrophy was classified into five subgroups according to a modified Kimura-Takemoto classification system and was compared with histological findings of atrophy at five biopsy sites according to the updated Sydney system.RESULTS: The strength of agreement of the extent of atrophy between histology and visual endoscopic inspection showed good reproducibili ty,wi th a weighted kappa value of 0.76(P < 0.001). Multivariate analysis showed that three factors were associated with decreased concordance: Japanese ethnicity [odds ratio(OR) 0.22,95% confidence interval(CI) 0.11-0.43],older age(OR = 0.32,95%CI: 0.16-0.66) and endoscopic atrophy(OR = 0.10,95%CI: 0.03-0.36). The strength of agreement between endoscopic and histological atrophy,assessed by cancer risk-oriented grading,was reproducible,with a kappa value of 0.81(95%CI: 0.75-0.87). Only nine patients(3.6%) were endoscopically underdiagnosed with antral predominant rather than extensive atrophy and were considered false negatives.CONCLUSION: Endoscopic grading can predict histological atrophy with few false negatives,indicating that precancerous conditions can be identified during screening endoscopy,particularly in patients in western countries.
文摘Gastric perforation is one of the most serious complications that can occur during endoscopic submucosal dissection(ESD).In terms of the treatment of such perforations,we previously reported that perforations immediately observed and successfully closed with endoclips during endoscopic resection could be managed conservatively.We now report the first case in our medical facility of a gastric perforation during ESD that was ineffectively treated conservatively even after successful endoscopic closure.In December 2006,we performed ESD on a recurrent early gastric cancer in an 81-year-old man with a medical history of laparotomy for cholelithiasis.A perforation occurred during ESD that was immediately observed and successfully closed with endoclips so that ESD could be continued resulting in an en-bloc resection.Intensive conservative management was conducted following ESD,however,an endoscopic examination five days after ESD revealed dehiscence of the perforation requiring an emergency laparotomy.
文摘A 67-year-old male underwent endoscopic submucosal dissection(ESD)to treat early gastric cancer(EGC)in 2001.The lesion(50 mm × 25 mm diameter)was histologically diagnosed as poorly differentiated adenocarcinoma,with an ulcer finding.Although the tumor was confined to the mucosa with no evidence of lymphovascular involvement,the ESD was regarded as a noncurative resection due to the histological type,tumor size,and existence of an ulcer finding(as indicated by the 2010 Japanese gastric cancer treatment guidelines,ver.3).Despite strong recommendation for subsequent gastrectomy,the patient refused surgery.An alternative follow-up routine was designed,which included five years of biannual clinical examinations to detect and measure serum tumor markers and perform visual assessment of recurrence by endoscopy and computed tomography scan after which the examinations were performed annually.The patient's condition remained stable for eight years,until a complaint of back pain in 2010 prompted further clinical investigation.Bone scintigraphy indicated increased uptake.Histological examination of biopsy specimens taken from the lumbar spine revealed adenocarcinoma resembling the carcinoma cells from the EGC that had been treated previously by ESD,and which was consistent with immunohistochemical findings of gastrointestinal tract cancer.Thus,the diagnosis of bone metastasis from EGC was made.The reported rates of EGC recurrence in surgically resected cases range 1.4%-3.4%,but among these bone metastasis is very rare.To our knowledge,this is the first reported case of bone metastasis from EGC following a non-curative ESD and occurring after an eight-year disease-free interval.
文摘It has been reported recently that small undifferentiated intramucosal early gastric cancer(EGC) < 20 mm in size without any lymphovascular involvement or ulcerative findings had virtually no risk of lymph-node(LN) metastasis.Consequently,the indications for endoscopic resection were expanded to include such undifferentiated EGC lesions.We describe herein a case of a small undifferentiated intramucosal EGC < 20 mm in size without lymphovascular involvement or ulcerative findings that involved lymph-node metastasis.A 57-year-old female underwent pylorus preserving gastrectomy as standard treatment for an undifferentiated EGC 15 mm in size without any ulcerative finding.The surgical specimen revealed a signet-ring cell carcinoma with a moderately to poorly differentiated adenocarcinoma limited to the mucosa that was 15 mm in size with no lymphovascular involvement or ulcerative findings.This case involved LN metastasis,however,and the lesion was diagnosed as pathological stage ⅡA(T1N2M0) according to the Japanese Classification of Gastric Carcinoma.
文摘An 80-year-old man was under annual surveillance esophagogastroduodenoscopy after endoscopic submucosal dissection(ESD) for early gastric cancer(EGC).Two years after the initial ESD, a 0-Ⅱc type metachronous EGC lesion, 8 mm in size, without an ulcer scar, was found in the gastric antrum.The estimated tumor depth was up to the mucosa, and biopsy revealed well and poorly differentiated adenocarcinoma.ESD was performed for this lesion and en bloc resection with negative margins was achieved.Histopathological examination revealed an adenosquamous carcinoma 8 mm in size invading the deep submucosal layer(1600 μm), with lymphovascular invasion, consistent with the diagnosis of non-curative resection.Additional gastrectomy was recommended for this patient; however, two months after the ESD, preoperative computed tomography revealed multiple liver metastases, and the patient was considered as an unsuitable candidate for surgical resection.Systemic chemotherapy was therefore started; however, the patient died of gastric cancer 27 mo after the second ESD.Early gastric adenosquamous carcinoma localized to the mucosa and submucosa is extremely rare and its clinical behavior is not well known.The present report is very significant in that it underscores the distinct possibility of gastric adenosquamous carcinoma being very aggressive and fatal even when detected at an early cancer.
文摘AIM: To evaluate the determination of the margin of differentiated-type early gastric cancers by using conventional endoscopy.METHODS: We retrospectively evaluated 364 differentiated early gastric cancers that were endoscopically resected as en-bloc specimens and diagnosed pathologically in detail between November 2007 and October 2008. All procedures were done with conventional endoscopes and all endoscopic samples, before and after indigo carmine dye, were re-evaluated using a digital filing system by one endoscopist. We analyzed the incidence of lesions with unclear margins and the relationship between unclear margins and relevant clinicopathological findings. RESULTS: The rate of lesions with unclear margins was 20.6%(75/364). Multivariate regression analysis suggested that the factors that make the determination of the margin difficult were normal color, presence of components of flat area(0-IIb), a diameter ≥ 21 mm, ulceration, and components of poorly differentiated adenocarcinoma in the mucosal surface.CONCLUSION: As many as 20% of differentiated early gastric cancers show unclear margins. Consideration of the factors associated with unclear margins may help endoscopists to accurately determine the margins of the lesion.
