Naoi Daishi, Koinuma Koji, Sasanuma Hideki, Sakuma Yasunaru, Horie Hisanaga, Lefor Alan Kawarai, Sugano Kokichi, Ushiama Mineko, Yoshida Teruhiko, Sata Naohiro
Division of Gastroenterological, General and Transplant Surgery, Department of Surgery, Jichi Medical University School of Medicine, Yakushiji 3311-1, Shimotsuke, Tochigi, 329-0498, Japan.
Genome Center, Genetic Counseling Clinic, Tochigi Cancer Center Research Institute, Tochigi, Japan.
Surg Case Rep. 2021 Jan 28;7(1):35. doi: 10.1186/s40792-021-01121-x.
Familial adenomatous polyposis (FAP) is characterized by the presence of hundreds to thousands of colonic polyps, and extracolonic manifestations are likely to occur. Pancreatic tumors are rare extracolonic manifestations in patients with FAP, among which solid-pseudopapillary neoplasm (SPN) are extremely rare. We report here a patient with an SPN of the pancreas found during the follow-up of FAP.
A 20-year-old woman was diagnosed with FAP 3 years previously by colonoscopy which revealed less than 100 colonic polyps within the entire colon. She complained of left upper abdominal pain and a 10-cm solid and cystic pancreatic tumor was found by computed tomography scan. Solid and cystic components within the tumor were seen on abdominal magnetic resonance imaging. Simultaneous laparoscopic resection of the distal pancreas and subtotal colectomy was performed. Histopathological findings confirmed the pancreatic tumor as an SPN without malignancy. Abnormal staining of beta-catenin was observed by immunohistochemical study. Multiple polyps in the colorectum were not malignant. Molecular biological analysis from peripheral blood samples revealed a decrease in the copy number of the promoter 1A and 1B region of the APC gene, which resulted in decreased expression of the APC gene.
A rare association of SPN with FAP is reported. The genetic background with relation to beta-catenin abnormalities is interesting to consider tumor development. So far, there are few reports of SPN in a patient with FAP. Both lesions were treated simultaneously by laparoscopic resection.
家族性腺瘤性息肉病（FAP）的特征是存在数百至数千个结肠息肉，并且可能会出现结肠外表现。胰腺肿瘤是FAP患者中罕见的结肠外表现，其中实性假乳头状瘤（SPN）极为罕见。我们在此报告1例在FAP随访期间发现胰腺SPN的患者。
一名20岁女性3年前经结肠镜检查诊断为FAP，结肠镜检查显示整个结肠内有不到100个结肠息肉。她主诉左上腹疼痛，计算机断层扫描发现一个10厘米的胰腺实性和囊性肿瘤。腹部磁共振成像显示肿瘤内有实性和囊性成分。同时进行了腹腔镜下远端胰腺切除术和结肠次全切除术。组织病理学检查结果证实胰腺肿瘤为无恶性的SPN。免疫组织化学研究观察到β-连环蛋白染色异常。结直肠内的多个息肉无恶性。外周血样本的分子生物学分析显示APC基因启动子1A和1B区域的拷贝数减少，导致APC基因表达降低。
报告了SPN与FAP的罕见关联。与β-连环蛋白异常相关的遗传背景对于考虑肿瘤发展很有意义。迄今为止，FAP患者中SPN的报道很少。两种病变均通过腹腔镜切除术同时治疗。
