🔑 Key Learning

  • Wilms tumour is the most common renal tumour in childhood, presenting as a painless abdominal mass, haematuria and flank pain in children < 4 years.
  • Neuroblastoma arises from neural crest cells of the sympathetic nervous system, often secretes catecholamines and presents variably depending on site.
  • Retinoblastoma presents in children < 3 years, often with leukocoria and strabismus, and is linked to RB1 tumour suppressor gene mutations.
  • All three conditions require urgent specialist referral for further investigation and management.

đŸ„Ź Wilms Tumour (Nephroblastoma)

Pathophysiology

  • The most common renal tumour in childhood (5% of all childhood malignancies).  

Clinical Features

  • Age < 4 years in 75% of cases.
  • Painless, rapidly growing abdominal mass.
  • Haematuria.
  • Hypertension.
  • Flank pain or fever.

Red Flags & Referrals

  • Palpable abdominal mass or organomegaly OR unexplained visible haematuria – very urgent referral (within 48 hours).

Investigations

  • Abdominal ultrasound (initial test).
  • Followed by CT or MRI for staging.

Management

  • Neoadjuvant chemotherapy followed by surgical resection.
  • Further chemotherapy ± radiotherapy based on staging.

🧠 Neuroblastoma

Pathophysiology

  • Malignant tumour of sympathetic nervous system.
  • Derived from neural crest cells.
  • Common primary sites: adrenal medulla, sympathetic ganglia  (abdomen, thorax, pelvis, neck).

Clinical Features

  • Usually diagnosed at around 2 years of age.
  • Abdominal mass: pain, distension.
  • Thoracic mass: respiratory symptoms, dysphagia.
  • Cervical tumour: Horner’s syndrome.
  • Metastases to bone marrow: fatigue, pallor, bruising.
  • Systemic symptoms due to catecholamine secretion: flushing, sweating, tachycardia, hypertension.

Red Flags & Referrals

  • Palpable abdominal mass or organomegaly – very urgent referral (within 48 hours).

Investigations

  • Urine catecholamines: elevated VMA/HVA levels.
  • Imaging: CT/MRI.
  • Biopsy to confirm diagnosis.

Management

  • Risk-adapted multimodal therapy: surgery, chemotherapy, radiotherapy, immunotherapy, stem cell transplant (if high-risk).

đŸ‘ïž Retinoblastoma

Pathophysiology

  • Malignancy of retinal cells.
  • Caused by mutations in the RB1 tumour suppressor gene on chromosome 13.

Genetic Subtypes

  • Germline mutation: bilateral tumours, high risk of additional malignancy (e.g. osteosarcoma).
  • Sporadic mutation: unilateral tumour, no increased risk of other cancers.

Clinical Features

  • Presents < 3 years (often < 1 year if bilateral).
  • Leukocoria – white pupillary reflex.
  • Strabismus (squint).
  • Decreased visual acuity.
Retinoblastoma. Leukocoria.

Red Flags & Referrals

  • Absent red reflex – urgent referral (suspected cancer pathway).

Investigations

  • MRI orbit/brain (for extent).

Management

  • Chemotherapy (systemic or intra-arterial).
  • Local therapies (cryotherapy, laser photocoagulation).
  • Enucleation if extensive disease.

📝 Exam Clues & Clinchers

  • Toddler with painless abdominal mass, haematuria and HTN → Wilms tumour → US abdomen, very urgent referral.
  • Flushing, abdominal mass, bone marrow failure signs in child < 5 → Neuroblastoma → urine VMA/HVA.
  • White pupil in infant photo → Retinoblastoma → absent red reflex → urgent ophthalmology referral.