A Randomized Controlled Trial Comparing Intrathecal Sustained-release Cytarabine (DepoCyt) to Intrathecal Methotrexate in Patients with Neoplastic Meningitis from Solid Tumors

Standard treatment for neoplastic meningitis requires frequent intrathecal (IT) injections of chemotherapy and is only modestly effective. DepoCyt is a sustained-release formulation of cytarabine that maintains cytotoxic concentrations of the drug in the cerebrospinal fluid (CSF) for more than 14 days after a single 50-mg injection. We conducted a randomized, controlled trial of DepoCyt versus methotrexate in patients with solid tumor neoplastic meningitis. Sixty-one patients with histologically proven cancer and positive CSF cytologies were randomized to receive IT DepoCyt (31 patients) or IT methotrexate (30 patients). Patients received up to six 50-mg doses of DepoCyt or up to sixteen 10-mg doses of methotrexate over 3 months. Treatment arms were well balanced with respect to demographic and disease-related characteristics. Responses occurred in 26% of DepoCyt-treated and 20% of methotrexate-treated patients ( P = 0.76). Median survival was 105 days in the DepoCyt arm and 78 days in the methotrexate arm (log-rank P = 0.15). The DepoCyt group experienced a greater median time to neurological progression (58 versus 30 days; log-rank P = 0.007) and longer neoplastic meningitis-specific survival (log-rank P = 0.074; median meningitis-specific survival, 343 versus 98 days). Factors predictive of longer progression-free survival included absence of visible central nervous system disease on neuroimaging studies ( P < 0.001), longer pretreatment duration of CSF disease ( P < 0.001), history of intraparenchymal tumor ( P < 0.001), and treatment with DepoCyt ( P = 0.002). The frequency and grade of adverse events were comparable between treatment arms. In patients with solid tumor neoplastic meningitis, DepoCyt produced a response rate comparable to that of methotrexate and significantly increased the time to neurological progression while offering the benefit of a less demanding dose schedule.