Primary leiomyosarcoma kidney - A rare entity with a diagnostic challenge

Primary leiomyosarcoma kidney is a rare tumor with an aggressive nature. Leiomyosarcoma is one of the common histologic types of the sarcomas, comprising 60% of all sarcomas. Sarcomatoid renal cell carcinoma is a close differential of renal leiomyosarcoma as both tumors have spindle-shaped cells. The former has a more pleomorphic character with nuclear grade four, which can be differentiated on the basis of immunohistochemistry. Hence, the diagnosis of primary renal leiomyosarcoma poses a diagnostic challenge. One such case of renal leiomyosarcoma in a 45-year-old male is being discussed here.