Unlike Wilms tumor, malignant rhabdoid tumors are monomorphous. The tumor is composed of sheets of monotonous round to ovoid cells. The characteristic tumor cells show eccentric nuclei due to ill-defined pale cytoplasmic inclusion bodes. On electron microscopy, the intracytoplasmic inclusions are due to whorled aggregates of intermediate filaments. Clinical presentation is similar to Wilms tumor with discovery of a renal mass in an infant.
Diagnosis is made histologically.
Malignant rhabdoid tumor is one of the most lethal of childhood malignancies. Most patients die of their tumor within one year. Tumors of the Kidney, Bladder, and Related Urinary Structures. Washington, AFIP, 1994. Search Medline at National Library of Medicine Please be patient during transfer.