Intrathecal chemotherapy is used to treat cancers that have spread to the CNS, such as certain types of leukemia, lymphoma, and metastases from other cancers. The blood-brain barrier, a protective shield that prevents toxins in the blood from entering the brain, also blocks most chemotherapeutic drugs. By administering the drugs directly into the CSF, this barrier is bypassed, allowing for effective treatment of CNS-involved cancers.
