Pleomorphic rhabdomyosarcoma of lumbar region: A case report

Abstract

Rhabdomyosarcoma is a malignant mesenchymal soft tissue tumour with tendency towards skeletal muscle differentiation. It is commonly seen in children and adolescents but is exceedingly rare in adults. The most common site in adults is the extremities. Less common locations include pelvis and thorax. The tumour is diagnosed by the morphologic presence of scattered pleomorphic rhabdomyoblasts and immunohistochemistry (with evidence of at least one skeletal muscle-specific marker). The outcome of tumour in adults is very poor, especially when compared to outcomes in children in whom significant improvements with treatment have been achieved. We present a case of Pleomorphic Rhabdomyosarcoma at the lumbar region which was clinically thought as a dermoid cyst. This case is reported because of rare location. The diagnosis was made on histopathology and immunohistochemistry. The tumour was diffusely positive for vimentin and desmin and focally positive for myogenin & MyoD1.