Nephroblastoma

Question 1

Introduction

Answer 1

*AKA Wilms tumour
*Malignant embryonic tumour of the kidney
* Second most common abdominal tumor in childhood
*Associated with congenital abnormalities
*Most cases are sporadic
* Familial in 1 to 2% of cases
*Any abdominal tumor must be considered malignant until proven otherwise

Question 2

Epidemiology

Answer 2

*Affects both sexes equally
*No racial predilection
*Age 2-5yrs
56-70% in under 5

Familial
Lower age at diagnosis
Higher frequency of bilateral involvement
Not associated with congenital anomalies
6% of childhood malignances

Question 3

Association

Answer 3

WAGR syndrome; Wilms, aniridia, Gut, mental retard.

Denys-Drash syndrome: Wilms, male pseudohermaphroditism and early onset renal failure

Beclwith-Wiedemann: macroglossia, hemi hypertrophy and visceromegaly

Deletion of 11p

Others:
pearlman syndrome, Soto syndrome, vonrecklinghausen dx,
von Willibrand

Question 4

WAGR syndrome;

Answer 4

Wilms, aniridia, Gut, mental retard.

Question 5

Denys-Drash syndrome:

Answer 5

Wilms, male pseudohermaphroditism and early onset renal failure

Question 6

Beclwith-Wiedemann:

Answer 6

macroglossia, hemi hypertrophy and visceromegaly

Question 7

Aetiology

Answer 7

• Unknown
• WT1 (Wilms tumour gene 1)
  11p13
  Encodes zinc finger transcription Factor (not as with familial)
• Familial is bilateral and developed at an early age
  30% risk of developing Wilms
• Bilateral involvement
  Synchronous
  Metachronos (one after the other)

Question 8

Pathology

Answer 8

• Favorable and unfavorable (anaplastic, clear cell sarcoma)
  Favorable is the most common
• Derived from blastema, epithelium and stroma
• Encapsulated mass
  May distort the renal outline

Question 9

Staging

Answer 9

National wilms tumor study group
I: limited to the kidney and completely excisable
II: extends beyond the kidney, completely resectable
III: residual non hematogenous spread, limited to the kidney
IV: hematogenous spread
V: bilateral involvement

Question 10

Clinical features

Answer 10

• Asymptomatic enlarging abdominal mass
• Smooth and firm abdominal mass
• Rarely crosses the midline
• Hypertension
• Microscopic hematuria
• Positive family history
  Lower age at diagnosis
  Autosomal dominant
  Bilateral involvement

Question 11

Investigations

Answer 11

Ultrasound

Intravenous Urography; intravenous urogram
Pelvicalyseal distortion and dispersion
Splaying of the calyses
Affected kidney not visualize in 30% of cases

Chest X-ray
Pulmonary metastasis

Question 12

Differential diagnosis

Answer 12

Abdominal Burkitts
Neuroblastoma
Abdominal tuberculosis
Polycystic kidney disease

Question 13

Treatment

Answer 13

Surgery, chemotherapy, radiotherapy
Pre Surgery chemotherapy
Post nephrectomy chemotherapy
VAC regimen
Vincristine, actinomycin d, cyclophosphamide