Hematologic Malignancies
Core concepts
Know the diagnostic framework: CBC and smear, flow cytometry, cytogenetics/FISH, and molecular testing (e.g., BCR-ABL, JAK2, FLT3, NPM1). Leukemias: AML induction with cytarabine/anthracycline and risk-adapted consolidation; APL is a medical emergency treated with ATRA plus arsenic. ALL uses Philadelphia chromosome testing to guide TKI use. CML is defined by BCR-ABL and treated with TKIs with molecular monitoring. Lymphomas: Hodgkin versus non-Hodgkin, aggressive versus indolent, and the role of rituximab, CHOP, and CAR-T. Multiple myeloma: CRAB criteria, M-protein and free light chains, and proteasome inhibitor/IMiD/anti-CD38 combinations. Myeloproliferative neoplasms and MDS round out the domain. Supportive care-tumor lysis syndrome, febrile neutropenia, and transfusion thresholds-is heavily tested.
Traps
Questions test APL recognition (do not wait for genetics before starting ATRA), the difference between induction and consolidation, and when to use growth factors. Watch for staging systems (Ann Arbor, ISS) and for distinguishing monoclonal gammopathy of undetermined significance from myeloma.
Rule of thumb
Suspected APL with bleeding and promyelocytes: start ATRA immediately; it is one of the few time-critical oncologic emergencies.
Worked example
A young patient with pancytopenia, DIC, and promyelocytes on smear: begin ATRA before confirmatory PML-RARA testing.