Quantification of sarcomatoid differentiation in renal cell carcinoma on magnetic resonance imaging

Renal cell carcinoma (RCC) accounts for 90–95% of renal tumors in adults, and about 2–3% of all adult cancers (1-3). Reported in approximately 5–10% of all RCCs, sarcomatoid differentiation in renal cell carcinoma (sRCC) is histologically characterized by the anaplastic transformation of RCC subtypes (4-6). These sarcomatoid features include pleomorphic spindle-like cells, high cellularity, and cellular atypia (4). Sarcomatoid differentiation is often associated with highly aggressive behavior, rapid recurrence, and a poor prognosis (5-9). RCC patients with a greater percentage of sarcomatoid components have been found to have a higher risk of death (9,10)