A 4-year-old child presents with abdominal mass, haematuria, and hypertension. CT scan shows a large unilateral intrarenal mass with nephroblastomatosis. FISH analysis shows loss of heterozygosity at 11p13 (WT1 gene deletion). What is the most likely diagnosis and the standard initial treatment in India (SIOP protocol)?

• A Neuroblastoma — MIBG scan and platinum-based chemotherapy
• B Renal cell carcinoma — radical nephrectomy upfront
• C Wilms tumour — upfront nephrectomy then chemotherapy (COG protocol)
• D Wilms tumour (nephroblastoma) — preoperative chemotherapy (vincristine + actinomycin D) followed by nephrectomy ✓

Explanation

Wilms tumour (nephroblastoma) is the most common renal malignancy in children (peak age 3–5 years). The SIOP (International Society of Paediatric Oncology) protocol — predominantly followed in India and Europe — recommends preoperative chemotherapy with vincristine and actinomycin D (for 4 weeks in localised disease) to downstage the tumour before nephrectomy, reducing intraoperative rupture and complications. The COG (Children's Oncology Group, North American protocol) recommends upfront nephrectomy. WT1 gene deletion at 11p13 is associated with Wilms tumour, particularly in the context of WAGR syndrome. Neuroblastoma arises from adrenal medulla/sympathetic ganglia and is retroperitoneal but not intrarenal.

Reference: Ghai Essential Pediatrics, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.