Volume effect in paediatric brain tumour resection surgery: analysis of data from the Japanese national inpatient database.

BACKGROUND:Paediatric brain tumours are the second most common type of malignancies that occur during childhood. Surgical resection is usually the first step in the treatment of these patients; however, evidence pertaining to a 'volume effect' in paediatric brain tumour resection surgery and the associations among the surgical volume, clinical features and treatments are not well characterised. METHODS:Data pertaining to paediatric patients (age ≤ 15 years) who underwent brain tumour resection surgery between April 2012 and March 2016 were retrieved from the Japanese administrative inpatient database and retrospectively analysed. Demographic characteristics, therapeutic procedures and in-hospital mortality were summarised according to the hospital surgical volume. Penalised logistic regression analysis was used to investigate the association between the hospital surgical volume and in-hospital mortality. RESULTS:A total of 1354 paediatric patients were included. About 40% of the patients were in the 11- to 15-year age group. The male:female ratio was 53:47, the overall crude in-hospital mortality was 1.8% (n = 24) and the 30-day postoperative mortality was 0.4% (n = 6). The crude mortality ratio was 3.3% in the lowest quartile and 0.8% in the highest quartile by volume. After adjusting for covariates, a higher hospital surgical volume was associated with lower in-hospital mortality (compared with 1-4 surgeries per 4 years, 15-25 surgeries, odds ratio [OR]: 0.25; 95% confidence interval [CI]: 0.05-0.90, p = 0.033; ≥26 surgeries, OR: 0.31; 95% CI: 0.08-0.96, p = 0.042). CONCLUSIONS:The present study indicated a volume-outcome relationship in paediatric brain tumour resection surgery cases. Further centralisation of surgeries should be considered to achieve better outcomes.