OBJECTIVETo explore the effect of BCR-ABL gene transcripts on Leukemia-free survival (LFS) and prognosis of patients with Philadelphia chromosome positive acute lymphoblastic leukemia (PhALL) after allogeneic hematopoietic stem cell transplantation (allo-HSCT).

METHODSThe clinical data of 107 cases of PhB-ALL patients received allo-HSCT from July 2006 to November 2014 in the First Affiliated Hospital of Soochow University were collected and the relationship between the clinical characteristics and LFS after transplantation was analyzed.

RESULTSOut of 107 PhALL patients (64 males and 43 females) with a median age of 30(7 to 54)years old, 35.5% (38/107) cases relapsed after transplantation within a median time of 6.9 (1.5 to 40.7) months. A total of 39 (36.4%) cases died within a median time of 19.8 (3.6 to 83.7) months after HSCT, of which 51.3% (20/39) due to disease relapse and 25.6% (10/39) due to infection. BCR-ABL gene transcripts of 49 cases turn into negative before transplantation, of which the expected 5-year cumulative incidence of relapse (CIR), non-relapse mortality (NRM) and overall survival (OS) were 26.5%, 29.5% and 41.6%, respectively. Another 49 cases still had a positive BCR-ABL gene transcripts before transplantation, of which the life expectancy of 5 year CIR, NRM and OS were 64.4%,8.9% and 48.9%, respectively. Compared with BCR-ABL positive patients, BCR-ABL negative patients showed a lower CIR (P<0.001), a higher NRM (P=0.030) and a similar OS (41.6% versus 48.9%, P=0.497). Multivariate analysis showed that BCR-ABL positive (P=0.016) and a disease statusphase ≥CR2 (P<0.001) before HSCT were independent risk factors for LFS, while the age underwent HSCT was the principal element affecting prognosis (P<0.001).

CONCLUSIONBoth the relapse and infection are the main causes of death in the patients after transplantation. A disease status ≥CR2 and the BCR-ABL positive before transplantation are 2 independent risk factors of LFS in the patients with PhALL after allo-HSCT.