An 18-month-old child has a large abdominal mass that does not cross the midline. Ultrasound shows a solid intrarenal mass with cystic areas. CT reveals involvement of the renal vein but no distant metastases. The most likely diagnosis and initial treatment is:

• A Neuroblastoma; platinum-based chemotherapy followed by surgery
• B Wilms tumour (nephroblastoma); pre-operative chemotherapy (SIOP protocol) followed by nephrectomy ✓
• C Renal cell carcinoma; radical nephrectomy upfront
• D Mesoblastic nephroma; surgery alone is curative in neonates

Explanation

Wilms tumour (nephroblastoma) is the most common renal tumour of childhood, typically presenting as a unilateral abdominal mass not crossing the midline in children 2–4 years old. Renal vein involvement places it at Stage III (NWTS) or implies local extension manageable with combined therapy. Under SIOP (International Society of Paediatric Oncology) protocol used in India, pre-operative chemotherapy (actinomycin-D and vincristine for 4 weeks) reduces tumour size and operative risk, followed by nephrectomy. Neuroblastoma typically crosses the midline.

Reference: Ghai Essential Pediatrics, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.