LWBK1006-32 LWW-Govindan-Review November 24, 2011 11:28
Chapter 32•Chronic Leukemias 457Answer 32.13. The answer is D.
The Philadelphia chromosome and BCR-ABL fusion gene are not pathog-
nomonic for CML. They are also observed in 25% to 50% of adult
patients with ALL and in rare cases in AML.Answer 32.14. The answer is D.
Tyrosine kinase inhibitors, such as imatinib, nilotinib and dasatinib, can
lead to good long-term disease control in patients with CML; however,
they are not curative. The only curative treatment of CML is hematologic
stem cell transplantation.Answer 32.15. The answer is D.
The breakpoint in ABL is highly variable, and is almost always upstream
of exon 2, which results in translocation of all but exon 1. BCR break-
points occur in two sites, between exon 13 and 14, or between exon 14
and 15; both of which carry a similar prognosis. The BCR-ABL fusion
protein resides in the cytoplasm.