Many different types of chemotherapy drugs are used in a variety of ways to treat different types of cancer. The benefits of chemotherapy include destroying cancer cells, shrinking existing tumors and preventing cancer cells from thriving and multiplying. The goal is to prevent or slow down the progression of disease to help extend life. Since these drugs can have serious side effects, chemotherapy benefits must be weighed against risk factors and expected outcome.
A cancerous tumor is a collection of abnormally growing cells. When chemotherapy is used to shrink an existing tumor, the benefit is to improve the patient's quality of life by decreasing the pain and pressure caused by the tumor. Although the tumor is likely to continue to grow or come back, shrinking a tumor can control the disease to the extent that a cancer patient will live longer. Chemotherapy is also used to shrink tumors prior to surgery or radiation treatments.
Because cancer cells can grow and spread quickly, one chemotherapy benefit is to slow down or prevent that growth. Chemotherapy can help prevent cancer cells from spreading from the original site to other parts of the body. At times, chemotherapy is used to destroy any cancerous cells that remain in the body after radiation treatment or surgery and may also be used to help make radiation treatments more effective. Chemotherapy is often the treatment used when cancer that was eliminated in the past comes back to the same area or to another part of the body. In advanced stages of cancer, chemotherapy may be used to help relieve symptoms and improve quality of life even though it cannot extend life.
In some cases, chemotherapy completely eliminates cancer cells or tumors from the body. According to the American Cancer Society, if the cancer does not return for many years, it may be considered cured, but since cancer can return at any time, physicians do not generally establish a complete cure as the primary chemotherapy benefit. Treatment plans and goals vary, as do the benefits expected from chemotherapy, depending on the type of cancer, or where it originated, and how advanced it is at the time of treatment.