Published online Mar 28, 2017. doi: 10.3748/wjg.v23.i12.2258
Peer-review started: December 8, 2016
First decision: January 10, 2017
Revised: January 23, 2017
Accepted: February 16, 2017
Article in press: February 17, 2017
Published online: March 28, 2017
Clear-cell sarcoma is a rare, malignant soft tissue tumor that displays melanocytic differentiation with a distinct molecular profile. It is rarely localized in the gastrointestinal tract. Herein we reported a case of multiple synchronous clear-cell sarcomas of the gastrointestinal tract with parotid gland metastasis. A 51-year-old male patient presented with a growing painless mass under the right ear. A preoperative positron emission tomography/computed tomography showed multiple intestinal masses and a mass in the right parotid with increased glucose uptake, and he underwent operative treatment with resection of three tumors in the jejunum and ileum and then received a right parotidectomy. Postoperative pathological examination showed that cells in the intestinal tumor were consistent with clear-cell sarcoma of the gastrointestinal tract, and the malignant cells in the parotid gland were similar to the intestinal tumor. Immunohistochemical studies revealed positive expression of HMB-45, Melan-A, and S-100. EWSR1 gene fusion transcripts were undetectable by fluorescence in situ hybridization.
Core tip: Over the past 13 years, only 53 cases of clear-cell sarcomas of the gastrointestinal tract (CCS-GI) have been reported in the world. Most of the literature on CCS-GI describes a single tumor at diagnosis; our presentation is the third report of simultaneous tumors during the diagnosis to date and is the first case of CCS-GI with metastasis to the parotid gland. We also reviewed the literature on CCS-GI. Because of the high rarity, more cases need to be accumulated for further analysis.