“Sugar” tumor of the pancreas: a rare entity that is diagnosable on preoperative fine-needle biopsies

Abstract

This study is the second to report a pancreatic "sugar" tumor (ST) case. This ST was incidentally discovered in a 31-year-old woman using computed tomography scan (CT scan) for work-up of a hepatic focal nodular hyperplasia. Both CT scan and endoluminal ultrasonography (EUS) features evoked a 15-mm large benign endocrine tumor. Pathological examination of EUS-guided fine-needle aspiration biopsies could not confirm this diagnosis. Laparoscopic corporeo-caudal pancreatectomy was performed. The tumor was intrapancreatic, well circumscribed, and organized in sheets of epithelioid cells. The tumor cells expressed HMB-45 but did not express epithelial or endocrine immunohistochemical markers. These histophenotypic features are those of an extra pulmonary ST, which belong to the PEComa family of tumors. Retrospective examination of preoperative biopsies evidenced the same histophenotypic features. This observation highlights that STs should be considered in preoperative differential diagnosis of pancreas tumors, since they may be treated by limited surgical resection.