Wilms' tumour

Question 1

What is the most common renal tumour in children?

Answer 1

Wilm’s tumour aka nephroblastoma

Question 2

Which mutations are associated with nephroblastomas?

Answer 2

WT1 = 11p13 chromosome

WT2 = 11p15 chromosome

Question 3

What type of gene is WT1?

Answer 3

Tumour suppressor gene

• Associated with Wilms tumour and Denys-Drash syndrome

Question 4

What is Denys-Drash syndrome?

Answer 4

Rare disorderconsisting of the triad of

1. congenital nephropathy
2. Wilms tumor, and
3. intersex disorders

Resulting from mutations in the Wilms tumor suppressor (WT1) gene.

Question 5

Discuss WT2 gene

Answer 5

• Tumour suppressor
• 11p15
• Mutations are associated with Beckwith-Wiedmann syndrome

Question 6

Is Wilms’ tumour always associated with WT1/2 mutations?

Answer 6

No - actually in most cases mutations in these genes are not found so the aetiology of this childhood renal caner remains unclear

Question 7

What is the main component of Wilms’ tumour?

Answer 7

Metanephric blastemal cells + partially developed structures of the nephron

Question 8

How does Wilms’ tumour present?

Answer 8

• Unilateral (bilateral in 6-10%)
• Painless
• Abdominal/ flank mass
• Pallor
• Haematuria
• Abdominal pain & distension
• Anorexia

Question 9

What is the initial test if Wilms’ tumour is suspected?

Answer 9

Ultrasound - showing a large echogenic, heterogenous, mainly solid intrarenal mass

Question 10

What age is most common for Wilms’ tumour presentation?

Answer 10

Age 2-5

Question 11

What would the physical examination findings be of Wilms’ tumour?

Answer 11

• Retroperitoneal mass
• Ballotable
• Does not move on respiration
• Smooth, firm and non-tender mass
• Abdomen may be distended

Question 12

Discuss Wilms’ tumour staging

Answer 12

1: Tumour limited to the kidney and completely excised. Renal capsule intact
2. Tumour extends through perirenal capsule but is completely excised. There may be local spillage of tumour confined to the flank. Extrarenal cessels may contains tumour
3. Residual nonhaematogenous tumour confined to the abdomen. LN involvement, tumour beyond the surgical marging
4. Haematogenous metastases to the lung, liver, bone, brain or other
5. Bilateral renal involvement at diagnosis

Question 13

When discussing cancer, what does haematogenous mean?

Answer 13

Spread by to blood

Question 14

What are the risk factors for Wilms tumour?

Answer 14

• Aged 2-5
• Family hx
• Congenital urogenital anomalies
• Congenital syndromes e.g. Beckwith-Wieldmann or Denys-Drash

Question 15

What is the 1st line treatment for Wilms’ tumour?

Answer 15

Radical nephrectomy

Question 16

What should a clinicial do if Wilms’ tumour is suspected?

Answer 16

• Refer to major paediatric cancer centre
• Chest x-ray to identify lung mets
• CT or MRI pelvis to look for signs of spread (occurs in <10%)

Question 17

What are the survival rates of Wilms’ tumour?

Answer 17

Long term survival approaches 90% in localised disease

Question 18

Discuss the epidemiology of Wilms’ tumour

Answer 18

• 1 in 100,000 before the age of 15
• Mean onset of age is 3.5yrs
• >80% diagnosed before the age of 5

Question 19

Which renal tumour most commonly affects children aged 15-19?

Answer 19

Renal cell carcinoma