An Assessment of Clinical Characteristics and Treatment Outcomes of Medulloblastoma Among Pediatric Patients Treated at Kenyatta National Hospital; a Five-year Retrospective Study

Abstract

Medulloblastoma is the commonest malignant central nervous system pediatric tumor with good survival outcomes >80% for standard risk as per Children Oncology Group study (COGA9961) and 60% for high-risk patients in developed nations, yet it has not been replicated in developing countries where 80% of children with such tumors live. These results are largely attributable to improved risk classification, skilled surgery, prompt radiotherapy, developments in radiological imaging, and supportive care that is offered in high income countries. Dissimilar outcomes in developing countries can be attributed to delays in diagnosis, delays in treatment, inadequate staging and risk-stratifying patients. Broad Objective: To assess treatment outcomes among pediatric medulloblastoma patients attending Kenyatta National Hospital. Methodology: This was a retrospective study that included data over a five-year period from 1st January 2018 to 1st January 2022. We included all the files of children with medulloblastoma aged below 13 years that met the inclusion criteria. Data analysis was carried out in R version 4.1.2. Continuous variables were summarized using median and interquartile ranges. Categorical variables were summarized using frequencies and proportions. Overall survival at 2 years was determined using Kaplan-Meier method. Prognostic factors for paediatric medulloblastoma were assessed using Cox regression analysis. Variables for multivariable analysis were selected using purposeful selection. Results were presented using hazard ratios and p values at 5% significance level. Results: The median age of the children was 7.5 years with an interquartile range of 3.8 to 10 years. Males were more than females in a ratio was 1.4. Eighteen percent of the cases were recurrent. The majority of the cases were new (82%, n = 41). The most common symptoms were headache (86%, n = 43), vomiting (72%, n = 36) and ataxia (38%, n = 19). The 2-year overall survival in this population was 73.6% (95% CI 62.3% to 87%). Age less than 3 years [HR 4.48, 95% CI 1.49, 13.47] and subtotal resection >1.5cm2 [HR 5.04, 95% CI, 1.59, 15.99] were significantly associated with poor prognosis under bivariate analysis but were insignificant under multivariable analysis. Conclusion: This study revealed that medulloblastoma affects more male children than females. The most common presenting symptoms of medulloblastoma were headache, vomiting and ataxia. The 2-year survival of paediatric patients with medulloblastoma in KNH is high as revealed in this study. Age less than 3 years and subtotal resection of >1.5 square centimetres were significantly associated with poor prognosis before adjustment. Medulloblastoma recurrence was significantly associated with poor prognosis before and after adjustment.