摘要
目的探讨小肠原发性恶性黑色素瘤的临床病理特点及鉴别诊断要点。方法对1例原发于十二指肠的恶性黑色素瘤进行组织形态学和免疫组化研究,并复习国内外相关文献。结果患者男性,60岁。临床表现为持续性右上腹痛伴黑便1个月;胃肠道钡餐检查示十二指肠降部充盈缺损;术中见十二指肠降部外侧2.5 cm×1.5cm×1 cm大小肿块一枚,侵犯浆膜,肠系膜触及直径3 cm淋巴结,切面均灰红色质软,未见色素;组织学表现为十二指肠黏膜下弥漫浸润的肿瘤细胞,圆形、卵圆形或多边形上皮样,胞质未见明显色素颗粒,胞核明显多形性、异型性,可见红核仁及核分裂象;免疫组化:黑色素抗原标记物HMB45、melan-A、S-100和vimentin均呈强(+)。术后随访38个月无复发。结论原发于小肠尤其十二指肠的恶性黑色素瘤非常罕见,临床症状及影像学表现不特异,少色素或无色素者极易误诊,确诊依赖于病理形态学及免疫组化标记,并需结合病史及全面体检排除转移可能。
Objective To investigate the clinicopathological characteristics and the main points of differential diagnosis of primary malignant melanoma originating in the small bowel.Methods The clinical presentation,histological observation and immunohistochemical staining were analyed in one case of primary malignant melanoma of the duodenum and related literatures were reviewed.Results A 60-year-old man complained of durative right abdominal pain and dark stools for one month.Gastrointestinal tract barium meal revealed a filling defect in duodenum.An exploratory laparotomy confirmed the presence of a solid tumor arising from the second part of the duodenum,which invadied the duodenal serosa and measured 2.5 cm×1.5 cm×1 cm.Enlarged mesentery lymph nodes of 3 cm diameter were identified.Cut surface of the specimens were both gray red and pliable without obvious pigment.Microscopic features manifested the lesions locatated under the enteric mucosa with diffusely infiltrative tumor cells.The latter were round,oval or polygonal epithelioid,with moderate cytoplasm,red nucleolus,more mitosis,but without obvious pigment.Immunohistochemical staining was positive for HMB-45,Melan-A,vimentin and protein S-100,and the patient had no evidence of recurrence for 38 months after surgery.Conclusion Primary malignant melanoma originating in the small bowel and particularly in the duodenum is extremely rare.There are no specific symptoms and radiologic imaging.The cases with little pigment or without notable pigment are very misleading.A definite diagnosis depends on pathomorphology and immunohistochemical stain.Detailed history and thorough investigation should be made to exclude the coexistence of a primary lesion elsewhere.
出处
《诊断病理学杂志》
CSCD
2011年第5期374-377,共4页
Chinese Journal of Diagnostic Pathology
