Diagnosis and treatment patterns for patients with leptomeningeal metastasis from solid tumors across Europe.

Leptomeningeal metastases are a late manifestation of systemic cancer which affects up to 10% of patients with solid tumors. Prognosis is poor, and overall survival at 1 year is only approximately 10%. Management depends mainly on general and neurological condition, primary tumor, and patterns of metastasis, notably absence or presence of concurrent systemic or solid brain metastases. Here we set out to characterize current practice patterns of diagnosis and treatment of patients with leptomeningeal metastasis in Europe. We prepared a web-based survey including 25 simple or multiple choices questions on best practice supplemented by eight case vignettes with various diagnosis and management options. The survey was sent to the membership of the European Association of Neuro-Oncology and the European Organisation for Research and Treatment of Cancer Brain Tumor Group. Between April 7, 2016 and August 8, 2016, 224 colleagues from 26 countries initiated the survey, 115 colleagues completed the whole survey. There were major differences both in the general diagnostic and therapeutic approach, e.g., regarding the use of cerebrospinal fluid (CSF) flow studies, intra-CSF chemotherapy, various types of radiotherapy, and even more so when selecting decisions on diagnostic and therapeutic measures for single case vignettes. Diagnosis and treatment decisions for patients with leptomeningeal metastasis from solid tumors vary widely across Europe. Standardization of diagnosis and evaluation tools as well as controlled studies to improve the level of evidence for all therapeutic approaches to LM are required.