Immunoreactivity for Ca 125 and INI 1 loss of expression are useful markers in the diagnosis of proximal type epithelioid sarcomas: report of two cases

Epithelioid sarcomas (ES) are rare soft tissue tumours of obscure histogenesis. Diagnosis is often difficult as specific morphological and immunohistochemical patterns do not exist. Two distinct clinico-pathological entities have been identified: the classic or distal type and the proximal type. Recently, immunohistochemical detection of Ca 125 was described in ES, as well as loss of INI 1 expression. The authors describe in this paper the morphological and immunohistochemical features of two cases of proximal ES of the vulva. Immunoreactivity for Ca 125 and loss of INI 1 expression were present in both cases. These results confirm previous observations in Asian reports showing that these markers can be used as immunohistochemical markers for the diagnostic assessment of ES.