A 29-year-old woman presents with gum bleeding and widespread ecchymoses. CBC: Hb 8.1 g/dL, WBC 14,000/uL with numerous abnormal promyelocytes containing Auer rods, platelets 16,000/uL. PT and aPTT are prolonged, fibrinogen 80 mg/dL, D-dimer markedly elevated. Which cytogenetic abnormality is expected?

• A t(9;22)(q34;q11.2)
• B inv(16)(p13q22)
• C t(8;21)(q22;q22)
• D t(15;17)(q24;q21) ✓

Explanation

The combination of Auer-rod-bearing promyelocytes and life-threatening DIC points to acute promyelocytic leukaemia, driven by the PML-RARA fusion of t(15;17), which blocks granulocytic differentiation at the promyelocyte stage. It is treated with all-trans retinoic acid plus arsenic trioxide. t(8;21) and inv(16) define core-binding-factor AML with a favourable prognosis, but they present as differentiated blasts without this consumptive coagulopathy.

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.