Is histopathological evidence really essential for making a surgical decision about mucinous carcinoma arising in a perianal fistula? Report of a case.

We report an unusual case of mucinous adenocarcinoma of the anus associated with a chronic anal fistula, treated successfully by abdominoperineal resection (APR). Although multiple biopsies failed to reveal any histological evidence of malignancy, cancer was diagnosed from the mucin obtained for cytology. Subsequent histological examination of the resected specimen revealed clusters of cancer cells floating in a mucous lake, suggesting that it would have been difficult to acquire the cells in a biopsy sample. Conversely, the presence of mucin lakes and globules in specimens drained from the region of perianal sepsis may have been histologically informative for diagnosis. Thus, although biopsy of the lesion is undoubtedly essential for diagnosis, it often fails to provide enough information to make a definite diagnosis of mucinous carcinoma. This case illustrates that clinicians should base their decision on whether to perform surgery on clinical manifestations, imaging findings, and cytology of mucin obtained by drainage when it is difficult to obtain malignant cells by biopsy.

Pancreatobiliary fistula associated with an intraductal papillary-mucinous pancreatic neoplasm manifesting as obstructive jaundice: report of a case.

We report a pancreatobiliary fistula caused by an intraductal papillary-mucinous pancreatic neoplasm (IPMN), manifesting as obstructive jaundice. Computed tomography showed dilatation of the bile duct and main pancreatic duct, with multiple cystic masses in the head of the pancreas. Endoscopic retrograde pancreatocholangiography showed a patulous papilla with mucin secretion. Contrast enhancement outlined amorphous material obstructing the lower part of the common hepatic duct. Pancreatogram and magnetic resonance cholangiopancreatography showed diffuse dilatation of the main pancreatic duct and side branches without communication with the adjacent organs or duct. We performed pancreaticoduodenectomy for IPMN of the pancreatic head and a tumor-like lesion in the lower common bile duct (CBD). Macroscopically, impacted thick mucus protruded into the CBD from the pancreas via a pancreatobiliary fistula. Histologic examination revealed a pancreatobiliary fistula caused by intraductal papillary-mucinous carcinoma of the pancreas with mucin hypersecretion, an adenoma without interstitial infiltration, and isolated implantation of an IPMN in the bile duct mucosa around the fistula.

Necrotizing fasciitis secondary to carcinoma of the gallbladder with perforation.

We present an unusual case of necrotizing fasciitis in the upper abdominal wall caused by penetrating perforation of the gallbladder. It was manifested as an elastic and reddish abdominal swelling with severe tenderness, but no peritoneal irritation. Computed tomography (CT) demonstrated water density with a slightly elevated CT value and air bubbles in the subcutaneous space. The preoperative diagnosis was subcutaneous abscess with fasciitis. At surgery, necrotizing fasciitis and subcutaneous abscess secondary to penetrating perforation of the gallbladder were revealed. Cholecystectomy and peritoneal irrigation were performed. Although no tumor was evident during surgery, a tumor located close to the perforation site was found just after the operation. Pathological examination revealed gallbladder carcinoma without stones. There have been very few previous reports of necrotizing fasciitis following gallbladder perforation. The presentation, diagnosis, and management of fasciitis, as well as carcinoma of the gallbladder with perforation, are discussed.