Cytogenetic analysis of blasts from a 28-year-old adult with acute lymphoblastic leukemia identifies t(9;22)(q34;q11.2) with BCR-ABL1 fusion. Which statement about this finding is correct?

• A It confers a favorable prognosis compared with hyperdiploidy in adult ALL
• B It predicts response to all-trans retinoic acid combined with chemotherapy
• C It carries a poor prognosis and usually involves the smaller p190 fusion protein ✓
• D It defines transformation of preexisting chronic myeloid leukemia and cannot arise de novo

Explanation

Philadelphia-positive ALL accounts for roughly 25% of adult ALL and carries one of the worst prognoses among ALL subgroups. In ALL the breakpoint is usually in the minor region producing the p190 BCR-ABL protein, unlike CML where p190 predominates only rarely and p210 is typical. Hyperdiploidy is favorable, ATRA targets PML-RARA, and although Ph-positive ALL can arise de novo, this case shows it does.

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.