Leptomeningeal metastasis from solid tumors: clinical features and its diagnostic implication

In this study, we examined the characteristics and aimed to increase the knowledge of clinical features of leptomeningeal metastasis (LM). The clinical data, including initial diagnosis and treatment of primary tumor, clinical manifestations, neuroimaging findings, cerebrospinal fluid (CSF) examination, were analyzed. For the patients with adenocarcinoma/breast cancer, the incidence of cranial lesions and cranial nerve paralysis was obviously higher than patients with small cell lung cancer. Whereas, the incidence of involvement of intravertebral canal was obviously lower than that of small cell lung cancer. Patients with adenocarcinoma/breast cancer showed more incidence of leptomeningeal enhancement compared to those with small cell lung cancer. Persistent severe headache was noticed in those with squamous carcinoma, and usually showed absence of abnormally LM-related neuroimaging and CSF cytological findings, which resulted in a challenge in the diagnosis of LM from squamous carcinoma. Patients with different primary tumors showed differential clinical features. Significant differences were observed in clinical features between patients with adenocarcinoma/breast cancer and small cell lung cancer. Our study contributes to the understanding of clinical characteristics of LM, and contributes to improvement of LM diagnosis in clinical practice.