Wilms Tumor

Snapshot

  • A 2-year-old girl is brought to the emergency room after her mother discovers a mass in the girl’s abdomen while bathing. The girl occasionally cries when urinating, but is otherwise asymptomatic, without any abdominal pain. On exam, she is found to be hypertensive. There is a palpable, non-tender mass on the right side, which does not cross the midline.  A chest radiograph is ordered to assess for lung involvement.

Introduction

  • Embryonal malignancy of the kidney
    • embryonic glomerular structure
    • aka nephroblastoma
  • Epidemiology
    • most common renal tumor of childhood
    • seen in otherwise healthy children < 4 years old
  • Pathogenesis
    • loss of function mutation of tumor suppressor genes WT1 or WT2
      • Wilms tumor 1 gene and Wilms tumor 2 gene
  • Associated conditions
    • WAGR syndrome 
      • Wilms’ tumor
      • Aniridia
      • Genitourinary anomalies
      • Retardation
    • Beckwith-Wiedemann syndrome
      • overgrowth
        • macrosomia
        • macroglossia
        • hemihyperplasia
        • organomegaly
      • abdominal wall defects
      • embryonal tumors
  • neonatal hypoglycemia

Presentation

  • Abdominal mass in previously healthy, asymptomatic child
  • Symptoms
    • fever
    • hematuria
    • dysuria
    • constipation
    • abdominal pain
  • Physical exam
    • palpable, painless abdominal mass
      • does not cross midline
      • hemihypertrophy of kidney due to increased vascular demands
    • hypertension
      • due to renin secretion
  • some present with aniridia

Evaluation

  • Abdominal ultrasound
  • Radiography or CT to detect lung metastases
  • Tissue diagnosis after surgical resection

Differential Diagnosis

  • Neuroblastoma 
  • Polycystic kidney disease 
  • Other primary renal malignancies

Treatment

  • Standard therapy
    • nephrectomy
    • chemotherapy
  • Post-surgery
  • screening for recurrence with abdominal ultrasound every 3 months

Prognosis, Prevention, and Complications

  • Prognosis
    • better prognosis with younger age
    • overall 5-year survival rate > 90%
  • Prevention
    • genetic counseling based on family history
  • Complications
    • nephropathy
    • hypertensionrenal failure