A malignant GU tumor commonly presenting with painless hematuria is:

• A. Prostate cancer
• B. Bladder cancer
• C. Wilms tumor
• D. Renal cell carcinoma

Answer: (D)

Painless hematuria is a classic presenting feature for several malignant tumors of the urinary tract, and renal cell carcinoma is the one most traditionally linked to this symptom. The tumor tends to bleed into the kidney and collecting system, so blood appears in the urine without causing pain. Patients may notice either gross or microscopic blood in the urine, and while the full triad of flank pain, hematuria, and a palpable mass can occur, the painless hematuria itself is the most common presenting sign.

Prostate cancer typically shows urinary obstruction symptoms or signs from metastasis rather than painless hematuria; Wilms tumor occurs mainly in children and presents as an abdominal mass rather than a primary symptom of blood in the urine; bladder cancer does present with painless hematuria as a hallmark, but in this context the renal cell carcinoma is the classic malignant renal tumor associated with painless hematuria in adults, making it the best fit.