Chronic myeloid leukemia response to imatinib predicted by quantitation of BCR-ABL transcript

06-02-2006

Chronic myeloid leukemia (CML) response to imatinib could be predicted by prospective quantitation of BCR-ABL transcript.

"Imatinib mesylate (STI571), a specific Bcr-Abl inhibitor, has shown a potent antileukemic activity in clinical studies of CML patients. Early prediction of response to imatinib cannot be anticipated," investigators in Italy reported.

"We used a standardized quantitative reverse-transcriptase polymerase chain reaction (QRT-PCR) for BCR-ABL transcripts on 191 out of 200 late-chronic phase CML patients enrolled in a phase II clinical trial with imatinib 400 mg/day," explained G. Martinelli and colleagues, University of Bologna. "Bone marrow samples were collected before treatment, after 12, 20 and at the end of study treatment (52 weeks) while peripheral blood samples were obtained after 2, 3, 6, 10, 14, 20 and 52 weeks of therapy.

"The amount of BCR-ABL transcript was expressed as the ratio of BCR-ABL to beta 2-microglobulin (beta 2M). We show that, following initiation of imatinib, the early BCR-ABL level trends in both bone marrow and peripheral blood samples made it possible to predict the subsequent cytogenetic outcome and response."

The researchers concluded, "We propose this method as the method of choice for monitoring patients on imatinib therapy. QRT-PCR studies may be able to identify degrees of molecular response that predict both complete cytogenetic response and long term stability, as well as patterns of response that provide an early indication of relapse and imatinib resistance."

Martinelli and colleagues published their study in Annals of Oncology (Prediction of response to imatinib by prospective quantitation of BCR-ABL transcript in late chronic phase chronic myeloid leukemia patients. Ann Oncol, 2006;17(3):495-502).

For additional information, contact G. Martinelli, University of Bologna, Institute Hematology & Med Oncology Seragnoli, Molecular Biology Unit, Via Massarenti 9, I-40138 Bologna, Italy.

The publisher of the journal Annals of Oncology can be contacted at: Oxford University Press, Great Clarendon St., Oxford OX2 6DP, England.

Keywords: Bologna, Italy, Bone Marrow, Chronic Myeloid Leukemia, Diagnosis, Diagnostics, Enzymes, Enzymology, Imatinib Mesylate, Late Chronic Phase, Oncology, Genetics, Prognosis, BCR-ABL.

This article was prepared by Clinical Oncology Week editors from staff and other reports. Copyright 2006, Clinical Oncology Week via NewsRx.com.