Renal pseudotumour following treatment of Wilms' tumour

A 9 1/2-year-old boy was found to have a mass occupying the lower pole of his left kidney, six years after his right kidney had been removed because of a Wilms' tumour. Investigation of the mass included angiography which demonstrated a mass with pathological arteries. Open biopsy of the mass revealed histological changes of nonspecific nephritis. It is probable that this nephritis was a result of radiation damage potentiated by concurrent treatment with actinomycin D, which he had received six years ago.