Source / episode info
- **Episode:**203
- **Title:**Divine Intervention Episode 203 – Leukemia’s and Lymphoma’s for the USMLE Step 2CK and Step 3 Exams.
- **Published:**2020-01-15
- Source:Episode page
One-liner
This episode reviews the classic presentations of hematologic malignancies, differentiating leukemias from lymphomas, detailing specific types (CLL, CML, Hodgkin), and reviewing myeloproliferative disorders like Polycythemia Vera and Myelodysplastic Syndrome.
High-yield summary
- Leukemia vs. Lymphoma: Leukemia often presents with peripheral blood abnormalities (e.g., marked leukocytosis or pancytopenia); lymphoma typically presents with localized lymphadenopathy, and the CBC may be normal.
- CLL Hallmark: Chronic Lymphocytic Leukemia (CLL) is characterized by absolute lymphocytosis, recurrent bacterial infections due to impaired B-cell function, and the presence of smudge cells on the peripheral smear.
- Hodgkin Lymphoma: The classic finding is the presence of Reed-Sternberg cells; it classically affects young adults/elderly (bimodal distribution) and is positive for CD15 and CD30 markers. Prognosis correlates with lymphocyte count (lymphocyte-rich > lymphocyte-depleted).
- CML Hallmark: Chronic Myeloid Leukemia (CML) involves the Philadelphia chromosome ({t}(9;22)), creating the {BCR-ABL} fusion protein, and is treated with a Tyrosine Kinase Inhibitor (TKI) like imatinib.
- Myeloproliferative Disorders: Polycythemia Vera (PV) involves elevated hematocrit/erythrocytosis due to JAK2 mutation; the primary treatment is phlebotomy to reduce blood volume and prevent hyperviscosity.
- MDS Hallmark: Myelodysplastic Syndrome (MDS) can present with peripheral cytopenias, often associated with a pseudo-Pelger-Huët anomaly (bi-lobed nucleus in neutrophils) and may mimic myeloproliferative disorders.
Learning objectives
- Differentiate the typical clinical presentations (CBC vs. physical exam) of leukemia versus lymphoma.
- Identify the characteristic findings and associated translocations for major leukemias (CLL, CML, AML).
- Recognize the classic signs and management principles for myeloproliferative disorders (PV, ET, PMF).
- Understand the immunophenotype and prognostic factors in Hodgkin Lymphoma.
- Differentiate between Myelodysplastic Syndrome (MDS) and Myeloproliferative Disorders (MPD).