Pediatric Surgical Oncology
Wilms versus neuroblastoma
The abdominal mass is the classic discriminator. Wilms tumour arises from kidney, is smooth, rarely calcifies, may extend into the inferior vena cava and presents with haematuria or hypertension; management is primary nephrectomy followed by adjuvant chemotherapy (COG) or pre-operative chemotherapy (SIOP). Neuroblastoma arises from the sympathetic chain or adrenal, crosses the midline, calcifies, elevates urinary VMA and HVA, and is staged by INRG criteria with MYCN amplification and age as the dominant biology.
Hepatoblastoma is marked by alpha-fetoprotein; PRETEXT staging guides resection, chemotherapy is standard and transplantation is an option in selected PRETEXT IV disease. Rhabdomyosarcoma arises in parameningeal and genitourinary sites and needs biopsy with molecular studies before multimodal therapy. Germ cell tumours are staged by site and marker profile.
Traps
Bilateral Wilms (5-10%) requires biopsy and nephron-sparing surgery rather than immediate radical nephrectomy. Tumour spill at operation upstages disease and mandates radiotherapy. Do not biopsy a presumed Wilms before imaging the IVC and the contralateral kidney. In a child with an anterior mediastinal mass, avoid general anaesthesia before tissue diagnosis because of airway collapse.
Worked example
A 3-year-old has a left flank mass crossing the midline with calcification and raised urinary VMA. Rule of thumb: midline plus calcification plus catecholamine excess equals neuroblastoma; the next steps are MIBG imaging and bone marrow assessment, not nephrectomy.