Seizure prevalence, contributing factors, and prognostic factors in patients with leptomeningeal disease.

Background: To determine seizure prevalence and contributing factors in patients with leptomeningeal disease (LMD).

Methods: Authors performed a retrospective review of 79 consecutive patients with a diagnosis of LMD. Associations between categorical variables were assessed using Chi-Square tests or Fisher's Exact tests. Survival was plotted with Kaplan Meier curves. Variables with a log-rank p-value of <0.20 were entered into a Cox Proportional Hazard regression analysis.

Results: Seizure prevalence in those with and without brain metastases was 22%. Of those who seized, 65% were admitted for this at least once while only one patient required intubation. Primary malignancy, type or route of chemotherapy administration, form of radiation therapy (craniospinal, focal, or whole brain), surgical treatment, location of LMD, and number of brain metastases did not influence seizure development. Only 13% of patients who never had seizures were on a prophylactic AED (anti-epileptic drug). In patients who had brain metastasis, there was no significant difference in prevalence of seizure before versus after LMD diagnosis suggesting that LMD does not significantly increase the risk of seizure compared to brain metastasis alone. A multivariate analysis revealed that while males trended toward inferior survival, only performance status and treatment with systemic chemotherapy showed a significant association with survival. Median survival time of patients after LMD diagnosis was four months.

Conclusion: The prevalence of seizure in LMD patients is 22%. There were no statistically significant predisposing factors to seizure development. ECOG and use of systemic chemotherapy were found to be significant prognostic factors.