A 50-year-old man presents with splenomegaly, leukocytosis (WBC 95,000/μL with myelocytes, metamyelocytes, and basophilia), and a Philadelphia chromosome (t(9;22)/BCR-ABL1 fusion) on karyotype. His blast count is 4%. Which of the following is the most appropriate first-line therapy?
- A Imatinib 400 mg daily ✓
- B Hydroxurea alone
- C Allogeneic hematopoietic stem cell transplantation
- D Cytarabine plus daunorubicin (7+3 regimen)
Correct answer: A. Imatinib 400 mg daily
Explanation
The clinical picture with Philadelphia chromosome (BCR-ABL1) and less than 10% blasts is consistent with chronic-phase chronic myeloid leukemia (CML). Imatinib (a BCR-ABL1 tyrosine kinase inhibitor) is the standard first-line treatment and has transformed the prognosis with 10-year survival exceeding 80%. Allogeneic SCT is now reserved for accelerated/blast crisis or TKI-refractory disease. Hydroxyurea may be used temporarily for cytoreduction but is not curative or definitively disease-modifying.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.