Leptomeningeal spread is a serious complication. Left untreated, average survival is only 2 months. The article talks about a few treatments but there is an interesting clinical trial going on specifically for patients with leptomeningeal spread: Brain Tumor-Specific Immune Cells (IL13Ralpha2-CAR T Cells) for the Treatment of Leptomeningeal Glioblastoma, Ependymoma, or Medulloblastoma It is too early to tell how good this works, but the alternatives do not seem that good either. Car-T cells have worked miracles in other cancers. This is a new type of Car-T cell treatment that hopefully will work for brain tumors! They picked the absolute worst situation to test it in - so if it does work we should know quickly. Unlike most immunotherapies, Car-T cells have the possibility (at least in other cancers) of working quickly.
Disclaimer: The company running the trial, Mustang Bio, is a sponsor of the Musella Foundation.