Nakaji So, Hirata Nobuto, Fujii Hiroyuki, Iwaki Kosuke, Shiratori Toshiyasu, Kobayashi Masayoshi, Wakasugi Satoshi, Ishii Eiji, Takeyama Hiroyuki, Hoshi Kazuei
Department of Gastroenterology, Kameda Medical Center, 929 Higashi-cho, Kamogawa, Chiba, Japan.
Department of Anatomic Pathology, Kameda Medical Center, Kamogawa, Japan.
Clin J Gastroenterol. 2013 Aug;6(4):329-33. doi: 10.1007/s12328-013-0392-z. Epub 2013 Jun 1.
The present case involved a 76-year-old man with a cystic mass in the head of his pancreas. The cystic lesion, which measured 17.7 × 9.8 mm, was first detected by ultrasonography (US) at the age of 72 years. Follow-up endoscopic ultrasonography (EUS) performed at 4 years after the lesion had first been detected revealed a mural nodule measuring 14.0 × 8.4 mm in the cyst. Endoscopic retrograde pancreatography (ERP) imaging revealed that the main pancreatic duct was in communication with the cyst and that there was no irregular narrowing of the main pancreatic duct. On the basis of these results, the patient was diagnosed with an intraductal papillary mucinous neoplasm (IPMN), and stomach-preserving pancreaticoduodenectomy was performed. A histopathological examination revealed that the interior of the cystic part of the lesion was lined by a pancreatic ductal epithelium. A pathological examination of the nodular lesion detected storiform fibrosis, severe lymphoplasmacytic infiltration, and hyperplasia in the pancreatic duct epithelium together with a small amount of mucus. On immunohistological staining, the infiltrating lymphoplasmacytes were found to be positive for IgG4. Accordingly, the patient was diagnosed with focal autoimmune pancreatitis (AIP). In conclusion, we reported a case of focal AIP mimicking IPMN. This case showed neither enlargement of the pancreas nor irregular narrowing of the main pancreatic duct.
本病例为一名76岁男性，胰腺头部有一个囊性肿物。该囊性病变大小为17.7×9.8毫米，72岁时首次通过超声检查（US）发现。在病变首次发现4年后进行的随访内镜超声检查（EUS）显示囊肿内有一个大小为14.0×8.4毫米的壁结节。内镜逆行胰胆管造影（ERP）成像显示主胰管与囊肿相通，且主胰管无不规则狭窄。基于这些结果，患者被诊断为导管内乳头状黏液性肿瘤（IPMN），并接受了保留胃的胰十二指肠切除术。组织病理学检查显示病变囊性部分的内部衬有胰腺导管上皮。对结节性病变的病理检查发现有束状纤维化、严重的淋巴浆细胞浸润、胰腺导管上皮增生以及少量黏液。免疫组织化学染色显示，浸润的淋巴浆细胞IgG4呈阳性。因此，患者被诊断为局灶性自身免疫性胰腺炎（AIP）。总之，我们报告了一例酷似IPMN的局灶性AIP病例。该病例既没有胰腺肿大，也没有主胰管不规则狭窄。
