Prognostic impact of clinical and radiological factors on leptomeningeal metastasis from solid cancers.

purposeThe number of leptomeningeal metastasis (LM) patients has increased in recent years, as the cancer survival rates increased. An optimal prediction of prognosis is essential for selecting an appropriate treatment. The European Association of Neuro-Oncology-European Society for Medical Oncology (EANO-ESMO) guidelines for LM proposed a classification based on the cerebrospinal fluid cytological findings and contrast-enhanced magnetic resonance imaging (MRI) pattern. However, few studies have validated the utility of this classification. This study aimed to investigate the prognostic factors of LM, including the radiological and cytological types.

methodsWe retrospectively analyzed the data of 240 adult patients with suspected LM who had undergone lumbar puncture between April 2014 and September 2021.

resultsThe most common primary cancer types were non-small-cell lung cancer (NSCLC) (143 (60%)) and breast cancer (27 (11%)). Positive cytology results and the presence of leptomeningeal lesions on contrast-enhanced MRI correlated with decreased survival in all patients. Nodular lesions detected on contrast-enhanced magnetic resonance were a poor prognostic factor in cytology-negative patients, while contrast-enhanced patterns had no prognostic significance in cytology-positive patients. Systemic therapy using cytotoxic agents and molecular-targeted therapy after LM diagnosis correlated with prolonged survival, regardless of the cytology results. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor treatment and systemic chemotherapy after LM improved the survival of EGFR-mutated and wild-type NSCLC patients with positive cytology results.

conclusionsThis study validated the efficacy of prognostication according to the EANO-ESMO guidelines for LM. Systemic therapy after LM diagnosis improves the survival of NSCLC patients.