Childhood Cancers:
● Leukemia
○ Acute: ALL, AML
○ Chronic: CML, CLL
● Lymphoma
○ Hodgkins (HL), Non-Hodgkins (NHL)
● Malignant Bone Tumors
○ Osteosarcoma, Ewing Sarcoma
● Neuroblastoma
● Wilm’s Tumor
Hematopoiesis:
Acute Leukemias:
● Acute leukemias represent a clonal expansion and arrest at a specific stage of
normal myeloid or lymphoid hematopoiesis.
● ACUTE leukemias constitute 97% of all childhood leukemias.
, ● ALL (Acute Lymphoblastic Leukemia)
○ 75%
○ 2,500-3,000 children diagnosed per year in US
● AML (Acute Myelogenous Leukemia)
○ 20%
○ 500 children diagnosed per year in US
Acute Lymphoblastic Leukemia:
● Etiology- unknown
● Clinical Symptoms:
○ Fever
○ Fatigue
○ Pallor
○ Organomegaly
○ Bleeding (bruising, petechiae, or purpura)
○ Lymphadenopathy
○ Bone pain
● Hematologic Effects (Bone Marrow Invasion)
○ Anemia
○ Neutropenia / Leukopenia
○ Thrombocytopenia
● Clinical Findings (Lymphoid System Infiltration)
○ Lymphadenopathy
○ Organomegaly
● Clinical Manifestations of Extramedullary Invasion
○ CNS Involvement
○ Painless enlargement of testis
● Diagnostic Studies:
○ CBC
■ Hgb – moderate to large reduction
● Normocytic, normochromic morphology
■ WBC – low, normal or elevated
■ Blood smear – Lymphoblasts* presents on blood smear
■ Platelets – low in 92% of patients
○ Blood chemistries
○ Bone Marrow Biopsy – must be done for diagnosis
■ BM usually replaced by blasts
■ Megakaryocytes usually absent
■ Blast cell is the hallmark for diagnosis
○ Chest Xray – looking for mediastinal mass
○ Lumbar Puncture – looking for CNS disease
, ● Classifications:
○ Pre-B cell ALL accounts for 80% of cases → Good prognosis
○ T- Cell ALL accounts for 15-20% of cases → Poorer prognosis
■ Older age at presentation
○ High initial WBC
○ Presence of extramedullary disease (thymus)
● Favorable Prognostic Factors:
○ Age 1-9 years
○ WBC <50,000
○ Precursor B cell
○ Genetic factors
○ No CNS difficulties
○ Early Response to therapy
○ Minimal residual disease (MRD) at end of induction
● Treatment
○ Supportive care measures before chemotherapy
■ Patients may be:
● Dehydrated, infected, bleeding, anemic
● Impaired renal and hepatic function
○ All regimens include the following elements:
■ Induction (aim for remission)
■ Consolidation (intensification of remission)
■ Prevention of CNS leukemia
■ Maintenance therapy
Acute Myeloid Leukemia:
● Age of incidence is constant except:
○ Peak in the neonatal period
○ Peak during adolescence
● Clinical Symptoms:
○ Mirrors ALL – fever, petechiae, N/N anemia, thrombocytopenia
● Morphology
○ Auer Rods are diagnostic
○ Myeloblasts
■ Must have 20% blasts on bone marrow biopsy for diagnosis
● Poor Prognostic Factors:
○ WBC > 100K
○ Monosomy 7
○ Secondary AML
○ FLT-3 ITD mutation (16.5% of peds AML)