Intrathecal administration of 131I radiolabelled monoclonal antibody as a treatment for neoplastic meningitis.

Fifteen patients with neoplastic meningitis received a single intrathecal injection of between 11 and 60 mCi of a 131I radiolabelled monoclonal antibody (MoAb), chosen for its immunoreactivity to tumour. Major toxicity was manifest as nausea, vomiting and headache (7/15 patients), reversible bone marrow suppression (3/8 patients) and seizures (2/15 patients). Nine patients were evaluable for either a tumour or clinical response. Six of these demonstrated an event-free response that was maintained for periods of between 7 and 26 months.