Leptomeningeal disease occurs when cancer cells migrate from your breast, lung, or some other part of your body to your cerebrospinal fluid (CSF). This liquid circulates nutrients and chemicals to the brain and spinal cord. Once cancer cells are in the CSF, they settle in a spot in the brain and/or spinal cord and grow. We call this condition neoplastic meningitis, carcinomatous meningitis, lymphomatous meningitis, and leukemic meningitis.
A combination of surgery, radiation, and chemotherapy treatment improves the prognosis for leptomeningeal disease. Some tumor types are especially sensitive to chemotherapy injected directly into the cerebrospinal fluid, either by lumbar puncture (“spinal tap”) or through a surgically implanted device called an Ommaya. Other kinds of tumors, such as lung cancers in non-smoking Asian women, respond remarkably well to oral chemotherapies.
Your body produces CSF continuously within brain cavities called ventricles. It is made from blood and travels from the center of the brain to the back of the brain, down the spinal cord, then back up the spinal cord. From there, the fluid goes over the surface of the brain, where it goes back into the bloodstream. Your body completely replaces CSF several times a day. If tumor cells enter CSF and survive, they can travel throughout the central nervous system, causing neurological problems. The most common problems are headaches, nausea, vomiting, double vision, weakness, loss of urine control, and difficulty walking, but leptomeningeal disease can cause almost any neurological problem, depending on where the cancer cells land.
We are seeing more and more leptomeningeal disease, partly because cancer patients are living longer and partly because many chemotherapies cannot reach sufficient concentrations in the spinal fluid to kill the tumor cells. It can be difficult to detect leptomeningeal disease because magnetic resonance imaging cannot always pick up the problem.
What is an Ommaya?
An Ommaya reservoir is also known as a ventricular access device. We surgically implant this device under your skin where it is connected to a thin, plastic tube that passes into the fluid-filled ventricles deep within the brain where the body makes CSF. The device easily allows us to easily and repeatedly access your spinal fluid without having to do a lumbar puncture (“spinal tap”), both to administer medication and test for the presence of tumor cells. Most neuro-oncologists believe instilling chemotherapy directly into the ventricles is superior to injecting them through a lumbar puncture because it is easier, less painful, and more quickly and accurately delivers the drug to your entire system.