Treatment and Prevention
Certain types of cancers can be prevented through lifestyle modifications - this is known as primary cancer prevention. Tobacco-related cancers (e.g., lung cancer) account for almost one-third of all fatal types of cancer; therefore, quitting smoking is key for preventing cancers of the mouth, throat, esophagus, and lungs. Avoiding and limiting sun exposure, and using adequate protection (SPF lotions and sunscreens) while in the sun, will reduce the risk for developing skin cancer. Diet is another important area for cancer prevention. A high-fat diet is associated with a higher risk for certain cancers (such as breast and prostate), while a high-fiber diet has long been thought to reduce the risk for colon cancer. Certain vitamins such as vitamin E and beta-carotene have a role in cancer prevention because they act like antioxidants in the body and get rid of free radicals that can damage cells and cause cancer.
Surgery, radiation, chemotherapy, and, for some cancers, hormones or hormone-blocking medications are all used to treat cancer. The goal of cancer treatment is to kill cancerous cells while killing as few healthy cells as possible in the process.
Surgery is used to remove cancer cells that are packed together. Half of all cancers are treated with surgery. Surgeons will also remove normal cells around the cancerous cells or tumor to determine if the cancer has spread or not. Once the cancer has spread, it's very difficult to remove cancer cells with surgery.
Radiation is used to treat localized cancers. Radiation therapy can take a number of different forms. A beam of radiation can be aimed onto the skin near the site of the cancer. The radiation kills the cancer cells. Unfortunately, it also kills healthy cells. Newer radiation machines are getting better at focusing the radiation only on the cancerous cells, and not the normal cells. Radioactive particles can also be injected into the blood. The particles stick to cancerous cells, but not to normal cells. Sometimes, small radioactive particles are placed right into an organ next to the cancer, giving the cancerous cells a much higher dose of radiation than the normal cells.
Chemotherapy is treatment that uses anti-cancer medications. It's often used when the cancer has spread into the bloodstream. For many cancers, a combination of medications is used because it works better than just one medication. A complete response to chemotherapy is when all detectable cancer has disappeared. However, some cancer cells may still remain in the body and are undetected. As a result, the cancer may grow back after a period of remission. A partial response is when the cancer shrinks by more than half. Unfortunately, many cancers become immune to the anti-cancer medications over time. There are certain types of cancers (e.g., breast cancer) that are influenced by hormones; they can be treated with hormones or hormone-blocking medications to slow their growth.
Genetic engineering is being used to control the genes that turn cancer growth on and off and to control the enzymes that allow cancer cells to continually divide and grow. Cancer vaccines, antibodies combined with poisons, and chemicals that turn off blood vessel growth in cancers, are some of the newer developments being investigated in the battle against cancer.