Adult brainstem glioma: a multicentre retrospective analysis of 47 Italian patients

Background and purpose: Adult brainstem gliomas are rare primary brain tumours with heterogeneous clinical course. The low frequency of these tumours makes it difficult to achieve high-quality evidence regarding prognostic factors, adequate therapeutic approach and outcome in such patients. Methods: In this retrospective study, we analysed clinical, radiological, molecular, prognostic and therapeutic factors in a series of 47 histologically proven adult brainstem gliomas recruited over a 20-year period (1998–2018). Results: Twenty-two patients were male, 25 female with median age of 39 years. The tumour involved one brainstem segment in 20 cases and 2 or more segments in 27. Contrast enhancement was reported in 28 cases. Surgical procedures included biopsy in 26 cases and partial/total resection in the remaining 21. Histological diagnosis was of low-grade glioma in 23 patients, high-grade glioma in 22 and non-diagnostic in 2 cases. Data regarding molecular biology were available for 22 patients. Median overall survival was 35 months, in particular 16 months in high-grade glioma and 84 months in low-grade glioma. At univariate analysis, tumour grade was the only factor with a statistically significant impact on survival time (p = 0,003), whereas younger age, better performance status and total/subtotal resection showed a trend to more prolonged survival. This study also confirms safety of biopsy/surgery in adult brainstem glioma patients and shows a clear trend to a more frequent assessment of molecular biology data. Conclusions: Further prospective multicentre efforts, and hopefully clinical trials, are necessary to improve outcome in this neglected glioma patient population.