Two cases of poorly differentiated synovial sarcoma arising from the chest wall - One case of Ewing sarcoma-like small cell type with death 4 years after the first presentation and one case of high-grade spindle cell type receiving postoperative adjuvant chemotherapy

Publication date: November 2019Source: Human Pathology: Case Reports, Volume 18Author(s): Shohei Matsuo, Emiko Tomita, Kenjiro Fukuhara, Akinori Akashi, Yoshitane TsukamotoAbstractWe experienced two cases of poorly differentiated synovial sarcoma (PDSS) arising from the chest wall. The first 42-year-old female patient was asymptomatic, but incidental chest roentgenogram showed a chest wall mass about 5-cm in maximal diameter with extrapleural sign. The chest wall mass was removed at other hospital. A tentative pathological diagnosis was mesothelioma with small cell features. After several courses of chemotherapy consisting of carboplatin and pemetrexed, the tumor recurred. On recurrence, the patient was referred to our hospital. Under the provisional diagnosis of recurrence of mesothelioma, a left extrapleural pneumonectomy (EPP) was performed. The tumor cells both in the surgical specimen of EPP and in previous surgical specimen at the first removal at other hospital consisted of small round cells. The differential diagnoses included Ewing sarcoma/primitive neuroectodermal tumor, PDSS (a small cell variant) and mesothelioma with small cell features. The immunohistochemical study showed no definite results. Further genetic testing showed the presence of SS18-SSX1, SS18-SSX2 and SS18 split signals and the absence of EWSR1-Fli1, EWSR1-ERG or EWSR1 split signals. The definite pathological diagnosis was PDSS, small cell variant. Additional chemotherapy, radiation therapy and mole...
Source: Human Pathology: Case Reports - Category: Pathology Source Type: research