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Flashcards in Oncology Deck (30):

What are the most common types of pediatric malignancies? Name the top 3.

1. Leukemia (40%)
2. Brain tumours (20%)
3. Lymphomas (15%)


What is the most common extracranial tumour in children?



What are the typical presenting features of leukemia?

Bone marrow failure
- Anemia
- Neutropenia: increased rate of infections
- Thrombocytopenia: easy bruising, gum bleeding etc.

Organ infiltration
- Gingival hypertrophy (esp. M4 AML)
- Hepatosplenomegaly (esp. ALL)
- Lymphadenopathy
- Testicular enlargement -- painless (esp. ALL)
- Bone: bone pain, pathological fractures
- Skin: leukemia cutis
- Eyes: Roth spots, cotton wool spots, vision changes

Constitutional symptoms
- Fever
- Weight loss
- Night sweats
   >> "B symptoms"

Leukostasis/hyperleukosis syndrome
- Diffuse pulmonary infiltrates
- Respiratory distress
- CNS bleeding 
- Altered mental status
- Myocardial infarction
- Priapism

Metabolic effects aggravated by treatment
- Increased uric acid: nephropathy, gout
- Released phosphate
- Released procoagulants: DIC (esp. M3 AML)

If T-cell lymphoma --> thymic enlargement/lymphoma mediastinal mass can cause airway obstruction


What is the definition of acute leukemia?

Presence of 20% or more blast cells in the bone marrow aspirate at presentation
>> Usually <5%


What are the differential diagnosis of leukemia in children?

- Miliary TB

Autoimmune diseases

Langerhan's cell histiocytosis: look for skin rash
>> Benign!
>> Characterized by cloncal proliferation of Langerhans cells (dendritics)
>> Painful bone swelling (esp. skull)
>> Rash: extensive eruptions on the skull, red papules in intertriginous areas
>> Diabetes insipidus is very common -- involvement of the hypothalamic-pit axis


What are the investigations helpful in the diagnosis for leukemia?

Blood tests
- Clotting profile in case of DIC (AML M3)
- Peripheral blood smear for blasts
   >> Circulating blasts with Auer rods are pathognomonic for AML M3
- Baseline RLFT
- Serum hormone levels (not necessarily for leukemia)
   >> AFP, B-hCG and LDH
        :: Germ cell tumours
        :: Hepatoblastoma
   >> Testosterone/estrogen
        :: Germ cell tumours
   >> Renin levels for Wilm's tumour
- Bone profile: primary bone tumours/metastasis
   >> Increased PO4: released from blasts
   >> Decreased Ca

Bone marrow aspirate
- AML >20%
- Morphologic, cytochemical and/or immunotypic features to establish lineage

Trephine biopsy

Urine (not for leukemia)
- Catecholamines for neuroblastoma

- Bone scan: for bone metastasis
- CXR: for lung metastasis
- CT/PET-CT/MRI brain as indicated
- ECG and MUGA scan prior to chemotherapy (baseline for cardiotoxicity)


What is the treatment for AML?


M3 AML with t(15:17) translocation -- all-trans-retinoic acid and arsenic trioxide

1. Induction: cytarabine + daunorubicin
2. Consolidation
3. Supportive care: screening for infection + transfusion
    >> Give allopurinol before chemotherapy to prevent gout
    >> A total of 4-6 courses of induction and consolidation tx over 4-6 months
    >> Each course is associated with 3-4 weeks of severe pancytopenia

Note: Treatment is much more aggresive in AML than in ALL, but
there is no evidence for CNS prophylaxis in AML


What is the management for ALL?

1. Induction: 4-5 weeks
2. Consolidation: 3-5 months
3. Maintenance treatment: up to 2-3 years
4. CNS prophylaxis: intrathecal methotrexate/irradiation

>> Intensive inpatient treatment for 6 months +
less intensive home maintenance treatment for up to 2-3 years


What is the prognosis for ALL?

5-year-survival rate: ~80%

- Good risk: 90%
- Intermediate risk: 70-80%
- Poor risk: 25%


What are the specific investigations to perform for neuroblastoma?

1. Urine catecholamines
2. Image-guided biopsy
3. For genetic markers for prognosis: n-myc amplification
4. Staging scans:
     - Bone scan
     - MIBG scan
     - CT/PET-CT
     - BM aspiration for Homer-Wright rosettes


What is the management for neuroblastoma?


1. Neo-adjuvant chemotherapy
2. Surgical debulking
3. Post-op chemotherapy
4. Radiotherapy
5. Autologous BM transplant
6. Target therapy
7. Differentiating agent: cis-retinoic acid


What is the most common cancer in the first year of life?


- Metastasis are common at presentation (>50%)


What is the most common age of presentation for leukemia?

Can occur at any age

Mean age of diagnosis: 2-5 years


What are the differential diagnoses for periorbital ecchymoses ("panda eyes")?

- Basal skull fracture: rule out child abuse
- Craniotomy
- Disseminated neuroblastoma
- Amyloidosis in multiple myeloma


What are the peak ages for Hodgkin lymphoma?

Bimodal peaks

- 15-34 years
- >50 years


What is the common age of presentation in non-Hodgkin lymphoma?

7-11 years


What is the defining feature of Hodgkin lymphoma?

Reed-Sternberg cells


What are the classifications of non-Hodgkin lymphoma?

1. Lymphoblastic
2. Large cell
3. Burkitt's
   >> T-cell VS. B-cell
   >> Always do a CXR for any mediastinal masses
   >> Rapidly growing tumour with distant metastases


What is the CHOP regimen and what is it used for?

Usually for Hodgkin lymphoma but can also be applied to non-Hodgkin lymphoma

C: Cyclophosphamide
H: Hydroxydonorubicin
O: Oncovin (Vincristine)
P: Prednisone

+ Rituximab in B-cell NHL


What is the prognosis for Hodgkin lymphoma?

>90% 5-year survival


What is the prognosis for non-Hodgkin lymphoma?

75-90% 5-year survival


What is the prognosis for AML?

50% 5-year event-free survival


What is the prognosis for stage 4 neuroblastoma?

40% 5-year event-free survival


What is the difference between allogenic and autologous bone marrow transplant?

Allogenic donor
- HLA (human leukocyte antigen) identical siblings
- Mismatched family donor
- Haplo-identical family donors (half-matched)
- Unrelated donor

- Patient's own bone marrow
- Used in AML
- Used in highly malignant solid tumours requiring high-dose chemotherapy that have potentially detrimental effects on the bone marrow (namely stage 4 neuroblastoma)


How is bone marrow transplant done?

Megadose chemotherapy +/-
total body irradiation to eradicate residual leukemic cells
>> infuse normal stem cells to reconstitute the bone marrow system


What are the indications for bone marrow/stem cell transplant in ALL?

- Early bone marrow relapse
- High risk (philadelphia chromosome, failed induction) ALL before relapse


What are some known specific side effects of asparaginase?

- Venous thrombosis
- Pancreatitis


What is hyperleukocytosis?

Total WBC >100x10^9/L

- A common presenting feature of leukemia
- Complications
   >> Intracranial hemorrhage
   >> Pulmonary leukostasis syndrome
   >> Tumour lysis syndrome
   >> Chest crisis
   >> Myocardial infarction
   >> Priapism


What are the features of malignant lymphadenopathy?

- Firm
- Discrete
- Non-tender
- Enlarging
- Immobile

>> Fluctuance, warmth or tenderness are more suggestive of benign nodes


Cancer is the second most common cause of death after injuries in children
after 1 year of age.