Chemotherapy consists of drugs that are used to treat cancer. These drugs usually work by interfering with the ability of cancer cells to grow and multiply, leading to death of the cancer cells. Chemotherapy drugs usually have effects not only on cancer cells but also on normal cells, especially those that grow and multiple more rapidly. Chemotherapy is often given via a vein, but some chemotherapy may be given by mouth. Which chemotherapy is used, what the dose should be, how often it is used and for how long is dependent on the type and stage of the cancer and specific patient characteristics. Chemotherapy may cure cancer in some situations, often in combination with surgery and/or radiation therapy. It may also be used to slow the growth and spread of advanced cancer. Sometimes chemotherapy may be used to reduce the risk of recurrence of cancer.
Targeted cancer therapies refer to those drugs that have an impact on a specific molecular pathway or protein important to the growth or spread of cancer. As researchers identify a particular molecular pathway as important for a specific cancer’s growth and spread, a drug can be designed to shut down or slow the cancer’s growth. This can lead to death of the cancer cells. Unfortunately not all cancers have pathways that can be targeted by drugs available today. Researchers are working hard to find new targeted therapies.
Like chemotherapy, these targeted therapies are often given via a vein or by mouth. Side effects from targeted therapies may be different from those expected with chemotherapy. Sometimes cancer may be treated only with chemotherapy or only with targeted therapy or sometimes with both. Chemotherapy and/or targeted therapy may also be used with surgery and/or radiation therapy to treat a cancer.