Macrocystic serous cystadenocarcinoma of the pancreas: the first report of a new pattern of pancreatic carcinoma.

Cystic pancreatic neoplasms are rare and include mucinous and microcystic cystadenoma (carcinomas) and the recently described macrocystic adenoma. Their accurate diagnosis is difficult by radiology, and histopathology remains the modality of choice. The case of a 42-year-old woman presenting with a gradually enlarging abdominal mass is reported. Imaging studies revealed a large unilocular cystic lesion in the pancreas. An exploratory laparotomy was done with excision of the cyst along with pancreas. Numerous microscopic sections revealed a serous neoplasm with atypical nuclear features and focal invasion of the cyst wall. A final pathological diagnosis of macrocystic serous cystadenocarcinoma of the pancreas was made. The patient has been doing well two years after surgery. This is the first case of a macrocystic serous cystadenocarcinoma of the pancreas, highlighting the need for extensive sampling of all cystic lesions of the pancreas in order to reach a correct diagnosis.