3. Paeds [Haem & Onc]

Question 1

Where do Wilms tumours originate?

Answer 1

Embryonal renal tissue

Question 2

What is the eponymous name for a nephroblastoma?

Answer 2

Wilms tumour

Question 3

What is the most common renal tumour of childhood?

Answer 3

Wilms tumour

Question 4

What’s the typical age at presentation for a Wilms tumour?

Answer 4

80% present before 5 years.
Median age 3.
Very rarely seen after age 10.

Question 5

Give 2 common presenting clinical features for a Wilms tumour.

Answer 5

Abdominal mass (often incidental)
Painless haematuria

Question 6

Give 4 less common clinical features that a Wilms tumour could present with.

Answer 6

Abdominal / flank pain
Hypertension
Anorexia
Anaemia (haemorrhage into the mass)

Question 7

What is the cure rate of a Wilms tumour?

Answer 7

80%

Question 8

What is the management of a Wilms tumour?

Answer 8

Initial chemotherapy
Delayed nephrectomy

Radiotherapy in advanced disease

Question 9

Investigations for a Wilms tumour (inc referral criteria).

Answer 9

Unexplained enlarged abdominal mass in children; paediatric review within 48 hours.

US
CT/MRI ; shows characteristic cystic and solid tissue densities

Question 10

What is the most common cause of thrombocytopenia in childhood?

Answer 10

ITP

Question 11

What is ITP usually caused by?

Answer 11

Destruction of circulating platelets by antiplatelet IgG autoantibodies.
The reduced platelet count may cause a compensatory increase of megakaryocytes in the bone marrow.

Question 12

3 clinical features of ITP.

Answer 12

Bruising
Petechiae
Purpura

Bleeding is less common than in adults and would maybe manifest as epistaxis or gingival bleeding. Rare complication is intracranial bleeding, 0.1-0.5%.

Question 13

Describe the classic age of onset + preceding situation of ITP.

Answer 13

Age 2-10
Onset 1-2 weeks post viral infection or vaccination (usually more acute than in adults)

Question 14

What type of hypersensitivity reaction is ITP?

Answer 14

Type II hypersensitivity reaction:
cytotoxic, IgG / IgM mediated

Question 15

What 2 investigations would be used to initially investigate ITP and what would they show?

Answer 15

FBC; isolated thrombocytopenia, often <10x10^9

Blood film

Question 16

What advice would you give to parents of a child with a new diagnosis of ITP on discharge?

Answer 16

Return to school
Avoid contact sports whilst plt count is low
Emergency contact numbers
Information about condition

Question 17

Treatment options for severe ITP?

Answer 17

Oral / IV prednisolone

IV Ig

Platelet transfusions in emergency (only transiently increase the plt count as they are destroyed by the circulating autoantibodies)

Question 18

Bone marrow studies can be done in ITP if there are atypical features. Give 6 atypical features.

Answer 18

Enlarged lymph nodes
Hepatosplenomegaly
Neutropenia (low wcc) or high wcc
Anaemia

Doesn’t resolve
Resistant to treatment

Question 19

Neuroblastoma is one of the top 5 causes of cancer in children. What tissue do neuroblastomas arise from?

Answer 19

Neural crest tissue in the adrenal medulla and sympathetic nervous system.

Question 20

What is the median age of onset of neuroblastoma?

Answer 20

20 months
Most common before the age of 5

Question 21

Give 6 clinical features of a neuroblastoma.

Answer 21

Abdominal mass
Pallor
Weight loss + malaise (from bone marrow suppression)
Bone pain and limp
Hepatomegaly
Paraplegia (from spinal cord compression)
Proptosis

Question 22

Investigation findings in neuroblastoma:

Answer 22

Raised urinary catecholamine metabolite levels (VMA/HVA)

US / MRI scan of mass
Biopsy
Calcification on AXR?

MIBG scan (maps metastatic tumours)

Question 23

What kind of scan is best for brain tumours?

Answer 23

MRI

Question 24

As some brain tumour types can metastasise within the CSF, what investigation (apart from MRI) is required for complete staging of the disease? + caution

Answer 24

LP

Any indication of raised ICP; neurosurgical advice

Question 25

What is the most common primary brain tumour in children?

Answer 25

Pilocytic astrocytoma

Question 26

What is a haemangioblastoma?

Answer 26

vascular tumour of the cerebellum

Question 27

Where does a medulloblastoma arise from?

Answer 27

Arises from the midline of the posterior fossa (infratentorial compartment) and spreads through the CSF system.

20% have spinal mets at diagnosis

Question 28

What type of tumour commonly arises in the 4th ventricle and are generally aggressive tumours that require complete resection and radiotherapy?

Answer 28

Ependymoma