A 4-year-old boy presents with an asymptomatic, unilateral abdominal mass discovered incidentally by his mother. Ultrasound reveals a solid, well-circumscribed renal mass with no involvement of the renal vein or IVC. There is no hematuria or hypertension. What is the most likely diagnosis?

• A Wilms tumor (nephroblastoma) ✓
• B Mesoblastic nephroma
• C Renal cell carcinoma
• D Multilocular cystic nephroma

Explanation

Wilms tumor (nephroblastoma) is the most common renal malignancy of childhood, typically presenting between 2-5 years as an asymptomatic flank mass. Renal cell carcinoma is rare in children. Mesoblastic nephroma occurs in infants under 6 months. Multilocular cystic nephroma is a benign lesion. The age (4 years) and presentation are classic for Wilms tumor.

Reference: Nelson Textbook of Pediatrics, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.