[The prognostic significance of proportion of blasts in bone marrow on day 14 during induction chemotherapy in patients with adult Ph-negative acute lymphoblastic leukemia].

OBJECTIVE: To investigate the prognostic significance of proportion of the blasts in bone marrow on day 14 (D14) during induction chemotherapy in patients with adult Ph-negative acute lymphoblastic leukemia (Ph (-) ALL).

METHODS: Newly diagnosed Ph (-) ALL patients with bone marrow morphology analysis on day 14 during induction chemotherapy were analyzed retrospectively. The proportion of the D14 blasts which had an impact on achieving a CR by the first induction chemotherapy and outcomes were determined by ROC curve.

RESULTS: 166 ALL patients including 94 male and 72 female were analyzed. The median age was 32 years (range, 18-64 years). The CR rate by the first induction chemotherapy was 74.7% with a total CR rate as 93.3%. By ROC analysis, 7.5% of the D14 blasts had the best sensitivity and specificity. The patients with D14 blasts ≥7.5% had lower CR rates after the first and overall induction chemotherapy compared with those with D14 blasts <7.5% (42.7% vs 85.9%, P<0.001 and 75.9% vs 95.6%, P=0.001 respectively). The probabilities of 5-year disease free survival (DFS) and 5-year overall survival (OS) were higher in the patients with D14 blasts<7.5% than those with D14 blasts ≥7.5% (49.8% vs 29.6%, P=0.006 and 52.4% vs 32.6%, P=0.010 respectively). Multivariate analysis showed that higher WBC or central nervous system leukemia at diagnosis, D14 blasts ≥7.5%, no CR after the first induction chemotherapy and receiving consolidation and maintenance chemotherapy rather than transplant were associated with poor outcomes.

CONCLUSIONS: Higher proportion of D14 blasts in bone marrow during the first induction therapy indicated poor prognosis in adult Ph(-) ALL.