[Clinical characteristics and outcomes of 59 patients with acute lymphoblastic leukemia positive for BCR/ABL]

Abstract

Objective: To study the clinical characteristics and outcomes of BCR/ABL-positive acute lymphoblastic leukemia (BCR/ABL360888725-ALL) and screen the prognostic factors for BCR/ABL360888725-ALL.

Methods: From January 2001 to May 2008, 59 patients (median age of 32 years ranging from 3 to 69 years) with the diagnosis of BCR/ABL360888725-ALL by fluorescence in situ hybridization received induction chemotherapy with VDLP-/+Ara-C regimen. The patients who failed to respond to the chemotherapy received subsequent consolidation chemotherapy with imatinib (400-800 mg/day) (17 cases) or allogeneic hematopoietic stem cell transplantation (allo-HSCT) (16 cases).

Results: Of the 59 patients, 32 (58.3%) achieved complete remission (CR) after the first induction cycle. In patients with peripheral white blood cell (WBC) count <30=10(9)/L, 30-99.9(9)/L and > or =100(9)/L, the CR rates were 75.0% (18/24), 56.3% (9/15) and 26.3% (5/19) (P=0.006), and the overall survival probability of 2 years ( OSs of 2-yrs) was 24.7%, 22.5% and 21.1%, respectively (P=0.180). According to the FAB classification, 56 cases were divided into L1, L2 and biphenotypic acute leukemia (BAL) subgroups, and their CR rates were 66.7% (6/9), 63.2% (24/38) and 22.2% (2/9) (P=0.029), with OSs of 2-yrs of 22.2%, 27.0% and 22.0%, respectively (P=0.623). In terms of immunophenotype grouping by EGIL, the patients with ALL, myeloid antigen-positive ALL and BAL had CR rates of 61.1% (11/18), 60.6% (20/33) and 12.5% (1/8) (P=0.039), and the OSs of 2-yrs of 22.7%, 21.0% and 18.8%, respectively (P=0.643). In 55 patients with known karyotype, the CR rates were 71.4%(5/7), 70.8% (17/24) and 37.5% (9/24) in normal, sole t(9;22) abnormality, t(9;22) with additional abnormalities groups (P=0.046), with the OSs of 2-yrs of 42.9%, 34.0% and 7.3%, respectively (P=0.000). The patients complicated by septicemia had significantly lower OSs of 2-yrs than those without septicemia (0% vs 38.8%, P=0.005). The OSs of 2-yrs were significantly higher in patients with consolidation chemotherapy with imatinib than those without (48.0% vs 11.2%, P=0.001), and allo-HSCT was associated with significantly higher OSs of 2-yrs than exclusive chemotherapy (54.2% and 8.5%, P=0.000).

Conclusion: BCR/ABL360888725-ALL with WBC> or =100 x 10(9)/L, presence of BAL diagnosed by FAB or FACM, t(9;22) with additional chromosome abnormalities all adversely affect the treatment results, and additional chromosome abnormalities and septicemia are associated with lower OSs of 2-yrs. Imatinib treatment and allo-HSCT can both improve the OSs of 2-yrs of the patients with BCR/ABL(+)-ALL.