title: Perivascular Epithelioid Cell Tumor in the Stomach.
abstract: Perivascular epithelioid cell tumors or PEComas can arise in any location in the body. However, a limited number of cases of gastric PEComa have been reported. We present two cases of gastric PEComas. The first case involved a 62-year-old woman who presented with a 4.2 cm gastric subepithelial mass in the prepyloric antrum, and the second case involved a 67-year-old man with a 5.0 cm mass slightly below the gastroesophageal junction. Microscopic examination revealed that both tumors were composed of perivascular epithelioid cells that were immunoreactive for melanocytic and smooth muscle markers. Prior to surgery, the clinical impression of both tumors was gastrointestinal stromal tumor (GIST), and the second case was erroneously diagnosed as GIST even after microscopic examination. Although gastric PEComa is a very rare neoplasm, it should be considered in the differential diagnosis of gastric submucosal lesions.
authors.affiliation: Department of Pathology, Seoul National University Hospital, Seoul, Korea.
authors.forename: Sun Ah
authors.initials: SA
authors.lastname: Shin
authors.affiliation: Department of Pathology, Seoul National University Hospital, Seoul, Korea.
authors.forename: Jiwoon
authors.initials: J
authors.lastname: Choi
authors.affiliation: Department of Pathology, Seoul National University Hospital, Seoul, Korea.
authors.forename: Kyung Chul
authors.initials: KC
authors.lastname: Moon
authors.affiliation: Department of Pathology, Seoul National University Hospital, Seoul, Korea.
authors.forename: Woo Ho
authors.initials: WH
authors.lastname: Kim
keywords: Gastrointestinal stromal tumors; HMB-45 protein, human; MART-1 antigen; Perivascular epithelioid cell neoplasms; Stomach neoplasms