Clinicopathological features with outcomes of a series of conventional and proximal-type epithelioid sarcomas, diagnosed over a period of 10 years at a tertiary cancer hospital in India.

Epithelioid sarcoma (ES) is an uncommon sarcoma. Lately, its variants, including proximal-type ES, have been recognized. The present study highlights clinicopathological features of 26 (65%) conventional and 14 (35%) cases of proximal-type ES. Thirty-eight percent of cases were seen in 21-30-year age group, including 77.5% cases in men. Extremities were the commonest sites in both the subtypes. Histologically, conventional-type ES displayed nodular tumor aggregates with necrosis, while proximal-type showed solid arrangement of large, "rhabdoid-like" cells. More cases (64.2%) of the proximal type were of grade 3. A range of differential diagnoses was considered. Most important immunohistochemical markers were vimentin, epithelial membrane antigen, cytokeratin, CD34, and desmin. Maximum (72.5%) cases were treated surgically. Recurrences and metastasis were observed more in the proximal type. The 7-year disease-free survival was 19.4% in the conventional and nil in the proximal subtype (p = 0.06). The overall survival rate was also lower in the proximal (31.3%) than conventional type (90.2%; p < 0.001). Other unfavorable parameters were deeper location, larger size, and higher tumor stage. This unusual sarcoma, with characteristic growth patterns, merits a proper histological evaluation, as it has many mimics. Proximal-type ES is rather a morphological subtype, associated with an aggressive course.

Scope of FNAC in the diagnosis of soft tissue tumors--a study from a tertiary cancer referral center in India.

BACKGROUND: Fine needle aspiration cytology (FNAC) forms one of the first diagnostic tools in the evaluation of tumors. Its role in diagnosing soft tissue tumors (STT) has been fairly documented, as well as debated. Present study was aimed at evaluating its scope in diagnosing 127 cases of soft tissue tumors. METHODS: Conventional Pap and MGG staining was available in all the cases. Immunocytochemistry (ICC) was performed in 15 cases. Histopathological details were available in 115 cases. RESULTS: 50% cases were referred for a primary diagnosis, while 26.8% & 22.8% cases were evaluated for recurrent and metastatic lesions, respectively. Extremities were the commonest sites. On FNAC, 101 cases (79.5%) were labeled as malignant, whereas 10 cases (7.9%) were labeled as benign. The remaining 16 cases (11%) were not categorized and were labeled as 'unsure/not specified'. Histopathological confirmation in 115 cases, gave a diagnostic accuracy of 98%, with a positive predictive value of 98% in malignant cases and a negative predictive value of 100% in benign cases. Two cases were false positive. Among the various cytological categories, 60 cases (47.2%) were of spindle cell type, followed by 32 (25.2%) of round cell type and 14 cases (11%) of lipomatous type. Other 12 cases (9.4%) were of pleomorphic type; 7 (5.5%) cases of epithelioid type and remaining 2 cases were of myxoid type. All the round cell, pleomorphic and myxoid type of tumors were sarcomas, whereas 73.3% cases of spindle cell type were labeled as 'malignant'. Exact cytological sub typing was offered in 58 cases, with rhabdomyosarcoma (RMS) as the most frequently sub typed tumor. The two false positive malignant cases were of fibromatosis and a pigmented schwannoma, on biopsy. Out of 28 metastatic lesions, lymph nodes were the commonest site for metastasis, with epithelioid tumors that formed highest percentage of metastatic cases. CONCLUSION: FNAC is fairly specific and sensitive in STT diagnoses for primary, recurrent and metastatic lesions. The cytological types, especially round cell and pleomorphic sarcomas, can be quickly identified. Clinicopathological correlation with ICC as an adjunct, are valuable in exact sub typing.

Proximal-type epithelioid sarcoma--a rare, aggressive subtype of epithelioid sarcoma presenting as a recurrent perineal mass in a middle-aged male.

BACKGROUND: Epithelioid sarcoma (ES) is an uncommon soft tissue sarcoma. Lately, subtypes of ES, including proximal-type ES have been recognized, with relatively few reports on such cases. CASE PRESENTATION: A 47-year-old male presented with a perineal soft tissue mass that was excised elsewhere and the biopsy was submitted for a review diagnosis. On histology, a multi nodular tumor was seen comprising sheets of oval to polygonal cells with moderate amount of cytoplasm. Interspersed were larger, rhabdoid cells with abundant eosinophilic cytoplasm and prominent nucleoli. Focal necrosis was noted. A wide panel of immunohistochemical (IHC) markers was performed to rule out a range of differential diagnoses, including a poorly differentiated carcinoma, a melanoma and a variety of sarcomas with epithelioid differentiation. On IHC, the tumor cells showed a polyphenotypic expression, including positivity for epithelial markers i.e cytokeratin (CK), CK7, EMA and mesenchymal markers like vimentin and CD 34. Desmin was focally positive. CK20, CEA, S-100, HMB-45, SMA, LCA and CD31 were negative. A diagnosis of a proximal-type ES was formed. Six moths later, despite adjuvant chemo and radiotherapy (CT and RT), the patient continued to have the lesion and was referred again. In addition to the earlier histological features, sections from the persistent tumor mass showed an increased number of larger cells along with multinucleated tumor giant cells. CONCLUSION: The value of identifying this uncommon tumor from a list of differential diagnoses is in view of its aggressive behavior, as seen in our case. A wide excision with clear margins is imperative with options of post-operative CT/RT in individual cases during a close follow-up.