A 72-year-old man has progressive fatigue and abdominal distension. Examination shows massive splenomegaly. CBC reveals anemia and thrombocytopenia with a leukoerythroblastic smear showing numerous teardrop-shaped red cells. Bone marrow aspiration yields no material. What is the most likely diagnosis?

• A Primary myelofibrosis ✓
• B Chronic myeloid leukemia
• C Myelodysplastic syndrome
• D Waldenstrom macroglobulinemia

Explanation

Megakaryocytic proliferation with fibroblast activation causes marrow fibrosis in primary myelofibrosis, producing the classic dry tap on aspiration, extramedullary hematopoiesis with massive splenomegaly, and a leukoerythroblastic smear with teardrop red cells. CML gives granulocytic leukocytosis rather than a dry tap, and myelodysplasia and Waldenstrom macroglobulinemia do not produce this degree of fibrosis or teardrop poikilocytosis.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.