Paediatric Haem-Onc Flashcards
Name the most common cancer in children.
Acute lymphoblastic leukaemia
Describe the pathophysiology of ALL.
Malignant proliferation of immature blast cells, usually B cell precursors, which infiltrate bone marrow and other organs of reticuloendothelial system.
Describe the symptoms/signs in ALL and explain why these occur.
Usually presents insidiously over several weeks but may present very rapidly.
- General
- malaise
- anorexia - BM infiltration
- anaemia: fatigue, pallor
- neutropenia: infections
- thrombocytopaenia: bruising, petechiae, nose bleeds
- bone pain (25%) - reticulo-endothelial infiltration
- hepatosplenomegaly
- lymphadenopathy
Name 2 risk factors for the development of ALL.
- age: 2-6 years
2. Down syndrome
Which investigations would you perform on a child with suspected ALL to confirm Dx?
- Bloods
- FBC: anaemia, thrombocytopaenia, neutropenia
- peripheral blood smear: blast cells +/- RBC abnormalities
- clotting screen: 10% have DIC at time of diagnosis - BMAT (diagnostic)
- >25% malignant blast cells
- for morphology, immunophenotyping + cytogenetics
Which Ix would you perform on a child with suspected/confirmed ALL to assess for disease spread?
- CXR: to identify mediastinal mass characteristic of T cell disease
- abdo. USS: may show renal enlargement from leukaemic infiltration or uric acid nephropathy as well as intra-abdo. adenopathy
- LP: to ID CSF disease
Which supportive treatments are required in a cild being managed for ALL?
- correction of any cytopaenias e.g. RBC or platelet transfusions
- additional hydration + allopurinol (to protect renal function against effects of rapid cell lysis)
- co-trimoxazole on 2-3 consecutive days each week (prophylaxis against Pneumocystis jirovecii pneumonia)
What is the definitive treatment for ALL?
Combination chemotherapy:
1. induction (4 wks): steroids + chemo (+ intrathecal chemo if CNS +ve)
- consolidation: continued systemic chemo + intrathecal chemo (+ CNS radiotherapy if CNS +ve)
- maintenance (2-3 yrs): continued systemic chemo +/- intrathecal chemo.
what is the prognosis for ALL in children? what are high risk factors?
80% survival with treatment.
Poor prognostic features:
- age <1 yr or >10 yrs
- WCC >50
- some tumour cytogenetic/molecular abnormalities
- slow response to initial chemo
- detectable minimal residual disease after induction therapy
a 5 year old girl presents with a 7 day history of frequent bruising and nose bleeds. O/E she has a purpuric rash. She had a viral URTI 2 weeks ago. What is the diagnosis and what is the pathophysiology of this? How would you manage her?
IMMUNE THROMBOCYTOPAENIC PURPURA
- most commonly occurs following a viral infection
- production of autoimmune IgG against platelet cell membrane antigen causing platelet destruction
Management:
- advice (e.g. avoid contact sport) and observational monitoring
- avoid aspirin and NSAIDs
How would you treat a child presenting with severe ITP (i.e. significant bleeding)?
1st line: prednisolone, IV immunoglobulin
2nd line: rituximab, high dose dexamethasone
what is the prognosis for childhood ITP?
Up to 80% completely recover within 6 months.
Some will develop chronic thrombocytopaenia, but most will require no Tx.
<0.5% develop intracranial haemorrhage.
what is your differential diagnosis for a child who presents with a petechial/purpuric rash?
Thrombocytopaenic causes:
- ITP
- leukaemia
- DIC
Non-thrombocytopaenic causes:
- Henoch-Schonlein purpura
- sepsis (meningococcal/viral)
- trauma