PE20.7 | Wilms Tumor — Summary & Reflection

KEY TAKEAWAYS

Wilms Tumor (Nephroblastoma) — key takehome points:

• Commonest renal tumour of childhood, peak 3–4 years; triphasic histology (blastemal + stromal + epithelial); anaplasia = poor prognosis.
• KEY EXAM RULE: DO NOT vigorously palpate a suspected Wilms tumour — capsule rupture → peritoneal spill → Stage III upstaging.
• Associated syndromes: WAGR (aniridia + WT1 deletion, ~50% risk), Beckwith-Wiedemann (macroglossia + hemihypertrophy, ~5–10% risk), Denys-Drash (nephrotic syndrome, >90% risk). Stage V = bilateral (6%).
• NWTS Staging I–V: I = confined/resected; II = capsule breach/complete resection; III = residual abdominal disease; IV = distant mets (lung most common); V = bilateral.
• Treatment: nephrectomy + actinomycin D + vincristine (Stage I–II); + doxorubicin + radiation (Stage III–IV); nephron-sparing for Stage V.
• vs Neuroblastoma: Wilms = smooth, unilateral, no calcification, normal catecholamines; Neuroblastoma = may cross midline, calcification, elevated VMA/HVA, worse prognosis in advanced disease.
• Prognosis: Stage I–II ~95% 5-year survival; Stage III ~90%; Stage IV ~85%; diffuse anaplasia ~50%.

REFLECT

Reflect on the intern in the hook scenario who was about to vigorously palpate the mass. This is a very common and understandable error — the physical examination instinct is to characterise a mass fully. What educational change would ensure that the next intern coming onto the ward knows this rule before encountering their first child with an abdominal mass? Think about how you will communicate this to juniors in your future role as a senior resident or clinician. How does the lesson here — that physical examination manoeuvres can have direct oncological consequences — apply to other cancer-adjacent scenarios you know of?