Lin Y.-C.TSEN-FANG TSAI2020-10-222020-10-2220031076-0512https://www.scopus.com/inward/record.uri?eid=2-s2.0-0037322354&doi=10.1046%2fj.1524-4725.2003.29029.x&partnerID=40&md5=f2a863c05b6e94fc9708fef06f43006chttps://scholars.lib.ntu.edu.tw/handle/123456789/517746BACKGROUND. Cutaneous metaplastic synovial cyst (CMSC) is a rare cystic tumor that is unfamiliar to most dermatologists. A traumatic history usually precedes its onset. CMSC is often misdiagnosed as suture granuloma clinically. A correct diagnosis requires histopathologic examination to reveal its characteristic features, that is, a cystic tumor line by synovium-like structure. OBJECTIVE. To describe a case of CMSC encountered during dermatologic surgery practice. We present an unusual case with elongated projections. METHODS. A case report and literature review are presented. CONCLUSION. The differential diagnosis of tender cutaneous cysts should include CMSC. Projections from the cyst wall may attain significant size and give the intraoperative impression of a "bag of worms".[SDGs]SDG3antibiotic agent; adult; article; buttock; case report; clinical feature; clinical practice; cutaneous metaplastic synovial cyst; diagnostic error; differential diagnosis; epidermoid cyst; female; granuloma; histopathology; human; intraoperative period; medical literature; neurofibroma; priority journal; review; skin defect; synovial cyst; synovium; Female; Humans; Middle Aged; Skin Diseases; Synovial Cystjournal article10.1046/j.1524-4725.2003.29029.x125623562-s2.0-0037322354