Maeda Takashi, Yugawa Kyohei, Kinjo Nao, Kayashima Hiroto, Imai Daisuke, Kawata Koto, Ikeda Shinichiro, Edahiro Keitaro, Takeishi Kazuki, Iguchi Tomohiro, Harada Noboru, Ninomiya Mizuki, Yamaguchi Shohei, Konishi Kozo, Tsutsui Shinichi, Matsuda Hiroyuki
Department of Surgery, Hiroshima Red Cross Hospital and Atomic-bomb Survivors Hospital, 1-9-6 Senda-machi, Naka-ku, Hiroshima, 730-8619, Japan.
Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
Surg Case Rep. 2020 Jul 6;6(1):160. doi: 10.1186/s40792-020-00921-x.
Mixed adenoneuroendocrine carcinoma (MANEC) of the common bile duct (CBD) is very rare, with only 10 reported cases. Here, we report a case of MANEC of the distal bile duct (DBD) that was surgically resected under a diagnosis of cholangiocarcinoma (CCA).
A 60-year-old male had epigastric pain and was admitted to our hospital for the treatment of a suspected CBD stone. Upon admission, laboratory findings revealed elevated hepatobiliary enzymes including serum aspartate aminotransferase, serum alanine aminotransferase, serum glutamyltransferase, and serum alkaline phosphatase. Both carcinoembryonic antigen and carbohydrate antigen 19-9 were negative. Computed tomography (CT) showed dilation of the CBD. Endoscopic retrograde cholangiopancreatography (ERCP) showed circumferential stenosis and a 5-mm elevated lesion in the DBD. Brush cytology showed atypical ductal cells, indicating adenocarcinoma (AC) of the DBD. Under a diagnosis of CCA of the DBD, a subtotal stomach-preserving pancreaticoduodenectomy was performed. Neither peritoneal dissemination nor lymph node metastasis was found. Microscopically, the lesion was seen to be composed of predominantly well-differentiated tubular AC in the superficial layer of the tumor, admixed with neuroendocrine carcinoma (NEC) in the deeper portion, indicating a diagnosis of MANEC of the DBD. After immunohistochemical staining, NEC components were positive for synaptophysin and CD56 and were for SSTR2, SSTR5, and mammalian target of rapamycin (mTOR). Three months postsurgery, postoperative adjuvant chemotherapy with S-1 was started. More than 3 years postsurgery, he is alive without recurrence.
MANEC is highly malignant, progresses rapidly, and has a poor prognosis. Preoperative diagnosis is difficult; therefore, identifying NEC components by immunohistochemical staining using resected specimens is important.
胆总管混合性腺神经内分泌癌（MANEC）非常罕见，仅有10例报道。在此，我们报告1例远端胆管（DBD）MANEC病例，该病例在诊断为胆管癌（CCA）的情况下接受了手术切除。
一名60岁男性出现上腹部疼痛，因疑似胆总管结石入院治疗。入院时，实验室检查结果显示肝胆酶升高，包括血清天冬氨酸氨基转移酶、血清丙氨酸氨基转移酶、血清谷氨酰转移酶和血清碱性磷酸酶。癌胚抗原和糖类抗原19-9均为阴性。计算机断层扫描（CT）显示胆总管扩张。内镜逆行胰胆管造影（ERCP）显示DBD呈环形狭窄，有一个5毫米的隆起病变。刷检细胞学显示非典型导管细胞，提示DBD腺癌（AC）。在诊断为DBD的CCA后，进行了保留胃的胰十二指肠次全切除术。未发现腹膜播散和淋巴结转移。显微镜下，病变在肿瘤表层主要由高分化管状AC组成，在深部与神经内分泌癌（NEC）混合，提示诊断为DBD的MANEC。免疫组化染色后，NEC成分突触素和CD56呈阳性，而SSTR2、SSTR5和雷帕霉素哺乳动物靶点（mTOR）呈阴性。术后3个月，开始使用S-1进行术后辅助化疗。术后3年多，他仍存活且无复发。
MANEC恶性程度高，进展迅速，预后差。术前诊断困难；因此，使用切除标本通过免疫组化染色识别NEC成分很重要。
