RESULTS
From January 2010 to December 2016 (before the modification of induction therapy, with improved social and financial support), 136 medical records of children with ALL (0-16 years) had previously been reviewed and published, and data were available for comparison.
From January 2017 through December 2020 (after modification of induction therapy, with improved social and financial support), 160 children (0-16 years) were diagnosed with ALL at MTRH. Their data on age, sex, duration of illness, and distance to the hospital had been collected at diagnosis and was available. In addition, we retrieved medical records for 123 of the 160 children. We collected data on outcomes (relapse/progressive disease, death, abandonment of therapy, event-free survival), health insurance, WBC count at diagnosis, ALL immunophenotype, and CNS disease status.
Table 1 illustrates the socio-demographic and clinical characteristics of the two cohorts. There was no difference in age and sex distribution between the two cohorts before (n=136) and after (n=160) modification of induction therapy with improved social and financial support. The number of patients with no health insurance (NHIF) decreased from 16% to 2% before (n=136) and after (n=123), respectively. Patients who had symptoms for 1-3 months were 68 (52%) and 72(45%) before (n=132) and after (n=156), respectively. The number of patients whose residence is >100 kilometers from MTRH increased from 60%(n=136) to 80%(n=157).
Table 2 shows the first treatment outcomes before (n=136) and after (n=123) the modification of induction therapy with improved social and financial support. Death, the most common cause of treatment failure in our setting, did not change significantly between the two periods. Most of the deaths were treatment-related in both periods. Abandonment decreased significantly between the two periods (p<0.03318). Most children abandoned treatment during maintenance therapy: 18 out of 33 in 2010-2016 (n=136) and 15 out of 17 in the 2017-2020 (n=123) period. Relapse/progressive disease decreased significantly (p<0.04136). Among children who had a relapse of their disease, it occurred during maintenance in 19(70%) and 12(67%) of them before (19/27) and after (12/18), respectively. Event-free survival increased significantly(p<0.00001) between the two periods.
Figure 1 shows comparisons of survival through induction between the two periods. Patients who died in induction decreased from 24% (32/136) to 17% (21/123) between the two periods. However, the difference was not statistically significant (p< 0.198). Figure 2 shows the comparison of treatment abandonment between the two cohorts. Treatment abandonment decreased significantly from 24% to 14% (p<0.03318).
The sex, duration of symptoms, distance to the hospital, and health insurance status did not significantly influence treatment outcomes and event-free survival estimates in both cohorts. Patients with relapsed or progressive disease were offered palliative therapy, and all died. In the 2017- 2020 cohort alone (no data for the 2010-2016 cohort), out of 24 children with CNS disease, 14(58%) died, 4(17%) were referred for craniospinal radiation (there were no radiotherapy services at MTRH), 3(13%) were among those who abandoned treatment, and 4(17%) were still alive with enhanced intrathecal chemotherapy.
However, age and WBC count at diagnosis significantly influenced event-free survival in the 2017- 2020 cohort. Figure 3(A) shows event-free survival by WBC count at diagnosis. Patients with WBC count <50 x 109/L had better event-free survival compared to those with >50 x 109/L (p<0.017). Figure 3(B) shows that children between the age of 1 year to 9 years had better event-free survival, while those below one year of age had the worst outcome (p<0.0001).
Figure 4(A) compares event-free survival estimates between the two cohorts. The EFS at three years significantly improved from 18% (95%CI, 0.123-0.268) to 41% (95%CI, 0.319-0.518) (p<0.0001). Figure 4(B) shows the overall survival estimates for the 2017- 2020 cohort alone (no data for the old cohort). This cohort’s 3-year overall survival (OS) estimate was 49.2% (95% CI, 39.1% to 62%).