Chemotherapy is a combination of drugs that target rapidly dividing cells. The drugs kill cancer cells or keep them from growing. Chemotherapy is often used for fast growing tumors. It may be used to treat brain tumors:

  • After surgery—to kill any remaining cancer cells and decrease risk of return
  • In combination with radiation therapy if surgery is not an option
  • For secondary tumors that spread to the brain if the primary tumor responds to chemotherapy drugs

Most chemotherapy is delivered to the blood stream through an IV. However, most chemotherapy drugs can not get to the brain because of the blood brain barrier (BBB). The BBB protects the brain from harmful substances in the regular blood flow, but it can also make some treatments (like chemotherapy) more difficult. To treat brain tumors, chemotherapy may be:

  • Oral—Taken by mouth.
  • Intrathecal—Delivered directly into the cerebrospinal fluid (CSF). This method allows drugs to reach the tumor inside the BBB.
  • Direct contact—A wafer is placed on or next to the tumor during surgery. The wafer dissolves over time. Since the wafer is in direct contact with the tumor, side effects to the rest of the body are minimized.

It is delivered in cycles over a set period of time. A medical oncologist will determine how many cycles of chemotherapy are needed and what combination of drugs will work best. Though it may be used in a variety of cancers, lymphomas or medulloblastomas may have best response to chemotherapy.

There are a variety of chemotherapy drugs. The choice and combination of drugs will be based on the type and location of the brain tumor. Not all brain tumors respond to chemotherapy. Chemotherapy drugs for brain tumors may include:

  • Carboplatin
  • Carmustine (BCNU) or lomustine (CCNU)
  • Cisplatin
  • Procarbazine
  • Temozolomide
  • Methotrexate
  • Vincristine

Though the drugs are targeted to brain tumor cells, they can affect healthy cells as well. The death of cancer cells and impact on healthy cells can cause a range of side effects. A medical oncologist will work to find the best drug combination and dosage to have the most impact on the cancer cells and least impact on healthy tissue. Side effects or complications from chemotherapy may include:

  • Nausea and vomiting
  • Fatigue
  • Mouth sores
  • Hair loss
  • Gastrointestinal problems, such as loss of appetite or diarrhea
  • Low blood cell counts, which can lead to anemia and neutropenia

A variety of treatments are available to help manage side effects including medication, lifestyle changes, and alternative treatments. In some cases, the chemotherapy regimen may be adjusted to reduce severe side effects. The earlier the side effects are addressed, the more likely they will be controlled with a minimum of discomfort.