Pediatric oncology II Flashcards
what is the most common malignancy in childhood?
ALL
what is the pathogenesis of ALL?
- lymphoid progenitor cell undergoes clonal expansion
2. altered expression of genes whose products contribute to normal development of B and T cells
what are the three main signs of leukemia?
- bone marrow infiltration
- extramedullary disease
- fever of malignancy
what are the manifestations of bone marrow infiltration in leukemia?
- anemia
- low platelets
- neutropenia
- bone pain
what are the manifestations of extramedullary disease in leukemia?
- lymphadenopathy
- hepatosplenomegaly
- orthopnea, cough
- gingival hypertrophy
orthopnea could alert physican to what type of mass?
mediastinal
what is the most helpful test in the diagnosis of ALL?
CBC
what % of ALL cases will show elevated WBC?
50%
what % of ALL patients will have 2 or more cytopenias?
95%
what are the primary accepted nongenetic risk factors for ALL?
prenatal exposure to x rays and high dose radiation
what is the presentation for precursor B cell ALL?
- bone marrow involvement
2. frequently also extramedullary - CNS, skin, gonads, lymph nodes, liver, spleen
what is the presentation for precursor T cell ALL?
- mediastinal mass
- high WBC
- prominent lymphadenopathy
what are the main prognostic factors in B cell leukemia?
- WBC count
2. age
what is the greatest predictor of outcome for ALL?
response of induction therapy in bone marrow within 28 days
what are the late effects of treatment for ALL?
- osteonecrosis, osteopenia
- neuropathies
- neuropsychometric concerns
- obesity
what are the prognostic indicators for AML?
- age
- race
- cytogenetics
what is the most common brain tumor in children?
astrocytoma
what are the signs of posterior fossa tumors?
ataxia, tremors, dysarthria, stiff neck, papilledema
what are the signs of brainstem tumors?
- extremity weakness
2. cranical nerve signs
what are the signs of hemispheric tumors?
- hemiparesis
- hemianopsia
- aphasia
- seizures
what is generally needed for brain tumor diagnosis?
surgery
what has the greatest impact on brain tumor outcome?
surgery
what is the treatment for a tumor that disseminates via CSF?
neuro-axis radiation prophylaxis
what role does chemotherapy have in childhood cancer cases?
adjunctive
astrocytomas are associated with what mutation in 50-80% of cases?
NF-1
what is the leading cause of morbidity and mortality among pediatric cancers?
brain tumors
what is the gene mutation associated with wilms tumor?
WT1
what are the anomalies and syndromes associated with wilms tumor?
- hemihypertrophy
- aniridia
- denys-drash syndrome
- beckwith-widemann syndrome
what are the main history symptoms associated with wilms tumor?
- hypertension
2. gross hematuria
what tests are used to evaluate for wilms tumor?
- CBC
- CT abdomen
- CT chest
- CXR
- abdominal US
what is the cause of retinoblastoma?
loss of both alleles of RB gene
where do neuroblastomas occur?
any neural crest tissue - adrenal, paraspinal sympathetic tissue
what is the clinical presentation for neuroblastoma?
- large abdominal mass crossing midline
- lower extremity weakness
- cervical, high thoracic mass - horner’s syndrome
what is the most common extracranial solid tumor in children?
neuroblastoma
what is the average age of diagnosis for neuroblastoma?
18 months
what are the poor prognositc indicators for neuroblastoma?
- age over 18 months
- myc-n amplification
- unfavorable histology
what are the tests to evaluate for neuroblastoma?
- urine catecholamines
- imaging - CT, bone scan
- BM biopsy
- lymph node evaluation
what are the differences between osteogenic sarcomas and ewings sarcomas?
- osteogenic - metaphysis of long bone
2. ewings - diaphysis of long bone, all other bones
