Clinicopathological Stratification and Early Surgical Outcome of Paediatric Medulloblastoma Patients at Kenyatta National Hospital

Abstract

Background: Brain tumors are the second most prevalent cancer in children, behind Leukaemia, and the most common solid tumour. Medulloblastomas (MBs) are the most prevalent malignant brain tumors in children (tumour grade IV according to WHO). These tumors are treated with surgery, radiation, and chemotherapy. Although long-term survival rates have significantly improved, the tumour is still incurable in around a third of patients, and long-term survivors experience cognitive deficiencies and other therapy-related adverse effects in large numbers. The effectiveness of treatment depends on the risk stratification of the patient based on the age at diagnosis, craniospinal metastasis, and the size of the residual tumour postsurgery. This guides adjuvant treatment and thus prognosis. Recent research suggests, however, that these clinical characteristics are insufficient for determining disease risk. According to recent studies, categorizing MBs based on histology and molecular abnormalities may aid in better risk assessment of patients, rationalizing therapeutic approaches, enhancing cure rates, lowering long-term side effects, and generating novel therapeutic techniques. All these impact post-surgical outcomes. This study seeks to evaluate risk stratification both clinically and based on histopathology of children presenting with Medulloblastoma and their impact on early outcome post-surgery at KNH. This will better inform therapeutic decisions and improve patient care. Broad Objective: To describe clinicopathological stratification and early surgical outcome of children being surgically managed for Medulloblastomas at KNH. Methodology: This was a combined prospective cohort and retrospective cohort study on childhood medulloblastoma patients who have undergone surgery at KNH from January 2019 to October 2022. Informed consent was obtained from the next of kin. At the patient interview, data collected included patient demographics, radiological details, surgical intervention, postoperative management, and whether the patient underwent adjuvant therapy. The followup period was up to 6 months or an end point of death. The main outcome measures included length of Intensive care unit (ICU) stay, length of hospital stay, the pattern of radiological presentation, histological types, duration of stay before initiation of adjuvant therapy, and reasons for the delay in initiation of adjuvant therapy. Data management and results: Data was collected using predesigned data collection forms, then entered in SPSS 26.0. Results: Twenty children with medulloblastomas were analyzed, fifteen patients in the retrospective arm and five in the prospective arm. The female-to-male ratio was 1: 1.22. On histopathology, 75% of the tumours were classic while 25% were desmoplastic in nature. A total of 13 patients underwent adjuvant therapy, constituting 65% of the patients analyzed. 80% of the patients were standard risk. At six months post-surgery, 75% of the patients were alive with 27% of that number exhibiting tumor recurrence. Duration of hospital stay, classic histological variant, and midline tumor location were the main risk factors associated with developing complications. The mortality rate at 6 months was 25% with overall survival of 75% and progression-free survival of 73.3%. Conclusion: The study shows that there were more males than females presenting with medulloblastomas. The most common location of the tumour was the midline as per imaging. Sixty-five percent of patients underwent permanent CSF diversion, and the commonest histological variant was the classic medulloblastoma. The majority of patients are of standard risk disease at 80%. The study also shows that midline tumour location, telovelar approach, and classic histologic variant are the factors associated with increased complication occurrence