Carcinosarcoma of the adult kidney.

Carcinosarcoma of the adult kidney is a very rare tumour and there are only a few well documented cases in the literature. In this report such a tumour is described from a 50-year-old white male, which progressed very rapidly with widespread metastases. Histologically, the tumour consisted of renal cell carcinoma and fibrosarcomatous components. The interesting features in this case were that both the carcinomatous and sarcomatous elements of the tumour exhibited metastases separately to various organs.