Devine Intervention Podcast - Episode 203: Leukemias and Lymphomas for USMLE Step 2CK & Step 3

Introduction

• Host: Devine, a medical resident
• Focus: Leukemias and lymphomas on USMLE exams, specifically Step 2CK & Step 3
• Objective: Provide strategies to correctly answer leukemia and lymphoma questions on NBME exams

Key Topics

Leukemias

• Presentation:
  • General Indicators: Elevated white blood cell count, anemia (low hemoglobin), and thrombocytopenia (low platelet count)
  • Age Associations:
    • ALL (Acute Lymphoblastic Leukemia): Young children; associated with Down syndrome
    • CLL (Chronic Lymphocytic Leukemia): Older adults; high white count with recurrent infections, smudge cells on blood smear
    • AML (Acute Myeloid Leukemia): Midlife; 15:17 translocation, treated with all-trans retinoic acid (or vitamin A derivative)
    • CML (Chronic Myeloid Leukemia): Midlife; 9:22 translocation (Philadelphia chromosome), treated with Imatinib

Lymphomas

• Presentation:
  • Primary indicator is lymphadenopathy without CBC abnormalities
  • Age Associations: Typically younger adults but can occur in older people
  • Symptoms: Chronic B symptoms (fever, night sweats, weight loss)

Types of Lymphomas

• Hodgkin's Lymphoma:

  • Reed-Sternberg cells presence
  • Often presents in young adults or older adults (bimodal age distribution)
  • CD15 and CD30 positive
  • Variants:
    • Nodular Sclerosis: Most common
    • Lymphocyte Rich: Better prognosis
    • Mixed Cellularity: Associated with eosinophilia and pruritus

• Non-Hodgkin's Lymphoma:

  • Diverse group, lacks Reed-Sternberg cells
  • Can involve various B-cell types

Other Conditions

• Burkitt's Lymphoma:

  • Associated with 8:14 translocation; c-MYC amplification
  • Recognized by 'starry sky' pattern on histology

• Multiple Myeloma:

  • Symptoms: CRAB (Calcium elevation, Renal failure, Anemia, Bone lesions)
  • Identified with SPEP/UPEP tests and Rouleaux formation in blood smear

Myeloproliferative Disorders

• CML: Myeloproliferative disorder involving BCR-ABL fusion

• Polycythemia Vera: Elevated red blood cell mass, JAK2 mutation

  • Symptoms include aquagenic pruritus and facial plethora
  • Treatment: Phlebotomy, hydroxyurea

• Essential Thrombocythemia: High platelet count, bleeding risk, JAK2 mutation

• Primary Myelofibrosis: Bone marrow obliteration, teardrop RBCs, dry tap on biopsy

Leukemias & Syndromes

• Hairy Cell Leukemia: TRAP positive, lymphocytes with fine projections
• Myelodysplastic Syndromes:
  • Associated with hyposegmented neutrophils or ringed sideroblasts
  • Linked with prior chemo/radiation or benzene exposure

Important Translocations

• 8:14 (Burkitt's Lymphoma)
• 9:22 (CML)
• 15:17 (AML)
• 14:18 (Follicular Lymphoma)
• 11:22 (Ewing's Sarcoma)

Conclusion

• This podcast offers essential high-yield information for exams focused on leukemias and lymphomas.
• Devine offers tutoring services and courses for various medical exams and applications.