Retrospective Study on Very Early Relapse of Childhood Acute Lymphoblastic Leukemia at a Reference Centre in Indonesia

Abstract

Introduction: The cure rate of Acute Lymphoblastic Leukemia (ALL) in low and middle-income countries is still low. Many factors contribute to relapses event, thus leading to failure of the treatment outcome. However, there are limited studies regarding the relapse of childhood cancer in Indonesia. This study determined demography, clinical, and characteristic laboratory differentiation between relapse and non-relapse in the bone marrow childhood ALL group.Methods: This was a retrospective descriptive study in children newly diagnosed with ALL ages 0-18 who completed the induction phase using the 2013 treatment protocol during the 2018 period in Pediatrics Hematology-Oncology Unit at a reference center hospital in Indonesia. Of 78 data collected from the Indonesian Pediatric Cancer Registry (IP-CAR) and Hospital Information System after excluding abandoned treatment or death during treatment, only 35 patients completed the overall therapy. We evaluated bone marrow relapse and classified it into 'very early' relapse that occurs at least 18 months from diagnosis, 'early' relapse between 18 and 36 months, and more than 36 months is called 'late' relapse. Chi-square test was used to elaborate association between relapse and sex, leukocyte count, morphological classification, risk stratification, nutritional status. Kruskal Wallis tests were used to elaborate on the association between relapse, age, and induction duration. P value<0.05 was considered statistically significant.Results: Among 35 patients in this study, seven patients experienced bone marrow relapse. Relapses were dominant in four male patients, four patients aged from 1-10 years old, six patients with leukocytes count below 50.000/mm3, six normal nutritional status patients, and six patients classified as L2 patients. All relapse events occurred in a very early stage. Four patients are classified as standard risk, and three patients are high risk. There were no significant differences among characteristics of the relapse and non-relapse groups.Conclusions: The observed relapse onset is less than 18 months from diagnosis (very early relapse) during maintenance treatment. However, we found no significant demography, clinical, and laboratory differentiation between relapse and non-relapse groups.