Intrathecal (IT) chemotherapy is used to treat cancers that have entered into the CSF. When a cancer has gotten into the CSF, it may be called CNS (central nervous system) involvement. Chemotherapy given intravenously and/or by mouth are typically not able to cross into the CSF, and therefore, are unable to treat these cancer cells. Giving chemotherapy directly into the CSF allows the medication to reach the cancer cells and minimizes the potential systemic (overall) side effects that intravenous chemotherapy can cause.
IT chemotherapy can be used to treat or to prevent cancer in the CSF. IT chemotherapy may be administered as part of a chemotherapy regimen or on an as needed basis. IT chemotherapy may not have been part of your original chemotherapy plan, but added because cancer cells are found in your CSF. Symptoms of cancer in the CSF include a change in the person's ability to think and speak, difficulty swallowing, headaches, seizures and changes in vision. To determine if cancer cells are present in the CSF, a procedure called a lumbar puncture is done.
Intrathecal chemotherapy is administered during a procedure called a lumbar puncture or through an ommaya reservoir (shunt). Prior to having IT chemotherapy, you will have you labwork done. You need to have a sufficient platelet count to ensure that your blood will clot at the site after the procedure. Your provider will also talk to you about medications that you take or allergies you have that could affect the procedure.