Imatinib induces a cytogenetic response in blast crisis or interferon failure chronic myeloid leukemia patients with e19a2 BCR-ABL transcripts [1]

Indications:3 patients with chronic myeloid leukemia with e19a2 rearrangement (myeloid blast crisis 1, chronic phase 2).

TypeofStudy:Efficacy of Glivec is reported in patients with chronic myeloid leukemia with the e19a2 rearrangement. Open study.

Patients:3 patients, 1 woman aged 23 years and 2 men aged 47 and 55 years. Duration of follow up was 12-18 months.

DosageDuration:400 mg daily (n=2), 600 mg daily (n=1). Duration: at least 6 months; therapy was interrupted due to side effects in 1 patient.

Results:All patients achieved complete cytogenetic response at 6 months. On FISH analysis, BCR-ABL/ABL value was 66.1%, 35.2% and 73.1%, respectively at baseline, falling to 4.5%, 8.3% and 4.9% at 6 months and to 0.1%, 4.6% and 0.8% at 12 months. All patients showed marked reduction of BCR-ABL transcript after 3 months of Glivec therapy. Patient 1 had a partial cytogenetic response with reduction of BCR-ABL transcripts at 3 months and achieved complete cytogenetic response at 6 months. This patient then underwent bone marrow transplant at 9 months. Patients 2 and 3 achieved complete cytogenetic response with Glivec treatment only. Patient 3 developed cytopenia early in treatment and Glivec was stopped until he recovered, then restarted.

AdverseEffects:1 patient developed cytopenia leading to temporary interruption of treatment.

AuthorsConclusions:In conclusion, these findings indicate that imatinib is also effective in the treatment of CML with e19a2 transcript encoding p230 protein. Further experience with imatinib treatment in this CML subtype is necessary because of the low incidence of CML with e19a2 transcript.

FreeText:Patient 1 was in blast crisis, patients 2 and 3 were in chronic phase and were resistant to alpha interferon. Tests: cytogenetic response, cytogenetics and interphase fluorescence in situ hybridization (FISH) of bone marrow, BCR-ABL transcript on real time polymerase chain reaction (RT-PCR), blood count.