title: Perivascular epithelioid cell tumor (PEComa) in the transverse colon of an adolescent: a case report.
abstract: Perivascular epithelioid cell tumor (PEComa) is defined as a very rare mesenchymal tumor of histologically and immuno-histochemically distinctive perivascular epithelioid cells. PEComa in the colon is very rare, with only a few reported cases so far. Because of its rarity, the clinical features and biological behavior of PEComa in the colon have yet to be established. A 16-year-old female patient with PEComa in the transverse colon was referred to our hospital for rectal bleeding. Laboratory data showed a hemoglobin level of 6.6 g/dL, WBC of 8,800/mm(3), and platelet count of 191,000/mm(3). Colonoscopy, barium enema, and abdominal computed tomography revealed a 2-cm, smooth-surfaced, round tumor with focal ulceration in the proximal transverse colon. The patient complained of abdominal pain one day after endoscopic polypectomy. She underwent a segmental resection for a perforated transverse colon. Immunohistochemically, the tumor cells showed strong diffuse positivity for HMB-45 while they were negative for c-kit, smooth muscle actin, cytokeratin, S-100, vimentin, desmin, chromogranin, synaptophysin, EMA, and CD-34. The diagnosis of PEComa was based on histological and immunohistochemical staining. The patient did not receive any adjuvant therapy and was discharged on postoperative day 11 without complications. Whole-body fluorine-18 fluorodeoxyglucose fusion positron emission tomography performed 2 months after surgery showed no signs of recurrence or metastasis. There was also no recurrence or metastasis at 24 months' follow-up.
authors: Department of Surgery, Gachon Medical School, Gil Medical Center, Incheon, Korea. gsbaek@gilhospital.com
authors: Jeong-Heum
authors: JH
authors: Baek
authors: Moon Gi
authors: MG
authors: Chung
authors: Dong Hae
authors: DH
authors: Jung
authors: Jae Hwan
authors: JH
authors: Oh
mesh_terms: D000293:Adolescent; D014408:Biomarkers, Tumor / Q000032:analysis; D002277:Carcinoma / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D044684:Colon, Transverse / Q000473:pathology; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D003113:Colonoscopy; D015622:Epithelioid Cells / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D014057:Tomography, X-Ray Computed
chemical_list: D014408:Biomarkers, Tumor