[Analysis of Correlation between Interval Time of Chemotherapy and Prognosis in Patients with Acute Leukemia].

Objective: To investigate the relationship between average interval time of chemotherapy and prognosis in patients with acute leukemia (AL) during intensive treatment.
Methods: Data of 92 newly treated adult AL patients who received chemotherapy in The First Hospital of Lanzhou University from January 2010 to June 2019 were analyzed retrospectively. The patients were divided into groups according to the average interval time of chemotherapy during intensive treatment, and its influence on prognosis was analyzed.
Results: The median interval of chemotherapy during intensive therapy was 38 (20-64) days. According to the average interval of chemotherapy, patients were divided into 4 groups, including < 30 days group, 30-39 days group, 40-49 days group and ≥ 50 days group. The 3-year overall survival (OS) rate of the four groups was (84.9±8.0)%, (73.5±8.7)%, (56.5±11.1)% and (41.8±13.6)%, respectively (P=0.008). The 3-year progression-free survival (PFS) rate of the four groups was (63.6±11.1)%, (52.8±10.2)%, (38.2±10.8)% and (14.0±9.0)%, respectively (P=0.001). After comparison between the 4 groups, it was found that OS and PFS in ≥ 50 days group were significantly shorter than those in < 30 days group (P<0.008). Multivariate analysis showed that risk stratification and average chemotherapy interval ≥ 50 days were the common adverse factors affecting OS and PFS.
Conclusion: The average chemotherapy interval ≥ 50 days during intensive therapy is an independent risk factor affecting the prognosis and survival of patients with AL. When the bone marrow is completely relieved and the peripheral hemogram recovers to an acceptable level, the consolidation therapy should be started as soon as possible. The interval < 30 days can significantly improve the prognosis compared with the interval ≥ 50 days.