A 32-year-old woman presents with gum bleeding and petechiae. Hemoglobin 8 g/dL, platelets 18,000/µL, WBC 22,000/µL with 60% blasts showing bilobed nuclei and dense granules. PT and aPTT are prolonged, fibrinogen is 80 mg/dL, and D-dimer is markedly elevated. Which cytogenetic abnormality should be confirmed before starting specific therapy?

• A t(8;21)(q22;q22)
• B inv(16)(p13.1q22)
• C t(15;17)(q24;q21) ✓
• D t(9;22)(q34;q11.2)

Explanation

The picture is acute promyelocytic leukemia: Auer rod-rich promyelocytes, disseminated intravascular coagulation with low fibrinogen, and the classic faggot cells on smear. APL is defined by t(15;17) producing the PML-RARA fusion transcript, which is the target of all-trans retinoic acid. t(8;21) and inv(16) are other core binding factor leukemias that lack the coagulopathy, and t(9;22) defines CML or Ph-positive ALL.

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.