OBJECTIVETo explore the factors influencing total complete remission (CR), recurrence, disease-free survival (DFS) rate and overall survival (OS) rate in adults with Philadelphia (Ph) chromosome negative acute lymphoblastic leukemia (ALL) and the effect of subsequent allogeneic hematopoietic stem cell transplantation (allo-HSCT) on prognosis.

METHODSThe clinical data of 87 adult patients with Ph negative ALL were retrospectively analyzed, the CHOP regimen plus L-asparaginase (L-Asp) was used for the induction therapy, and the CHOP+ modified Hyper-CVAD or methotrexate was set up as the consolidation chemotherapy regimen. After consolidation chemotherapy for 3-6 courses, 45 patients (51.72%) received allo-HSCT , and 42 patients (48.28%) continually received the maintained consolidation chemotherapy. The average follow up time of the surviving patients was 40.13 (3-60 months).

RESULTSOut of 87 patients with PhALL one patient died (1.15%). In 86 patients who could be evaluated, 68 cases (79.67%) reached CR at the end of 1 course, 80 cases obtained CR (93.02%). Multivariate regression analysis showed that the enlargement of lever, spleen and lymphomode, WBC count≥ 100×10/L were affecting factors for total CR (P<0.05). Among 80 cases with CR, 27 cases (33.75%) relapsed, 5 years' overall survival (OS) rate and disease-free survival (DFS) rate were 47.50% and 45.00% respectively. Multivariate regression analysis yet showed that the induction chemotherapy without L-Asp, presence of CNS leukemia at diagnosis, absence of allo-HSCT and no CR after indution chemotherapy for 4 weeks were affecting factors for relapse and poor prognosis of patients (P<0.05). According to 4 prognostic factors such as presence of CNS leukemia or no, WBC count≥100×10/L or no, induction chemotherapy with L-Asp or no and CR after induction chemotherapy for 4 weeks or no, 86 patients were divided into low-risk group (without poor prognostic factor), middle-risk group (with 1 poor prognostic factor), high-risk group (with 2-4 poor prognostic factors). Statistical results showed that allo-HSCT treatment in low-risk group had no significant effect on OS and DFS (P>0.05). The rate of OS and DFS in middle and high-risk group were significantly higher than those of patients without allo-HSCT treatment (P<0.05).

CONCLUSIONPatients with central nervous system leukemia, high white blood cell count (≥100×10/L), induction chemotherapy without L-Asp, no CR after 4 weeks of chemotherapy and absence of allo-HSCT treatment are the factors influencing the prognosis of adult patients with Ph negative ALL, so the patients with those poor prognostic factors should take active treatment of allo-HSCT.