Combination chemotherapy refers simply to the use of more than one chemotherapy medication at a time to treat cancer. In the past, cancer was often treated with a single drug, but current treatments for many types of cancer use a combination of two or more different drugs simultaneously.
History of Combination ChemotherapyThe use of combination chemotherapy to treat cancer was inspired in the 1960s when scientists wondered whether the approach to treating tuberculosis – using a combination of antibiotics to reduce the risk of resistance – would work for the treatment of cancer as well. Using this approach, cancers that had previously been almost universally fatal such as acute lymphocytic leukemia and Hodgkin’s lymphoma became largely curable. Since that time, combination chemotherapy has been adopted for the treatment of many other cancers as well.
BenefitsThere are several theoretical advantages to using a combination of chemotherapy medications rather than single agents alone. Some of these include:
- Decreasing the chance that a tumor will be resistant to the treatment. Just as a combination of antibiotics may be used in case a particular bacteria is resistant to one of the medications, using two or more chemotherapy drugs reduces the risk that a tumor will be resistant to the treatment.
- Making it possible to give all medications as early as possible in the disease.
- Being able to address several targets in the cancer process at the same time. Cancer is a complex disease involving many steps. The use of chemotherapy medications that work on different molecular targets, or points in the cancer process should in theory raise the chances of eliminating the cancer.
- Recently research is also looking at ways in which using a combination of chemotherapy medications can be used to allow oncologists to use some of the drugs at lower doses, and hence reduce the likelihood of toxic effects.
In practice, the use of combination chemotherapy with many cancers has either been found to improve survival, or result in a better response to treatment.
Possible DisadvantagesIt goes without saying that any time more medications are used it is more likely that side effects will occur. In addition, if a patient develops a side effect when several medications are used, it may be difficult to know which of the medications is responsible.
ExamplesThere are many combinations of chemotherapy drugs that are used for different types of cancer. An example with lung cancer is using the combination of Platinol (cisplatin) and Navelbine (vinorelbine) to treat non-small cell lung cancer.
Sometimes an acronym is used to describe combination chemotherapy. One example is ABVD for Hodgkins disease which stands for the combination of the chemotherapy medications Adriamycin (doxorubicin), Blenoxane (bleomycin), Oncovin (vinblastine) and DTIC-Dome (dacarbazine).
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Zimmermann, G. et al. Multi-target therapeutics: when the whole is greater than the sum of the parts. Drug Discovery Today. 2007. 12(1-2):34-42.