Oncology and Radiotherapy

The medical field concerned with the research and treatment of cancer is known as oncology. Oncologists will often further focus their practices, some choosing to focus on a specific type of cancer such as breast cancer or leukemia; while others focus on one of the three generally accepted cancer treatments: surgery, chemotherapy and radiation, also known as radiotherapy. Often, patient care employs a combination of two or more of these treatment types.

Radiotherapy

• The National Cancer Institute describes radiotherapy as using high-energy radiation in an effort to kill cancer cells and shrink tumors. This radiation may come from a number of different sources, including x-rays, gamma rays, neutrons and protons. Radiation therapy may be external or internal--occasionally both types are employed. External radiation therapy is performed by a machine directing a laser at the body in the area of the tumor. Internal radiation may be either systemic or localized. Systemic radiation introduces a radioactive substance into the blood, which then travels throughout the body, while localized internal radiation involves the surgical implantation of substances, often called seeds, directly adjacent to a tumor.

Indications

• Radiotherapy may be used against all solid tumors, regardless of their location including the brain and reproductive organs. It is also used to treat cancers of the blood and lymph tissues, such as leukemia and lymphoma. The type of radiation used, as well as its dosage, will be determined based upon multiple factors including the type of cancer and whether or not the tumor is near organs that may be damaged during radiotherapy, according to the National Cancer Institute.

Side Effects

• The side effects of radiation therapy vary from patient to patient, and some will depend on the tumor location and type of radiotherapy used. Oncolink describes the common side effects of radiation as including constipation, diarrhea, skin reactions, dry mouth, loss of appetite, low blood cell counts, nausea and vomiting, fatigue and localized hair loss. Oncologists will help patients manage their side effects as part of their ongoing care.

Considerations

• Radiotherapy is directed at killing cancer cells, but it is somewhat imprecise, meaning that healthy tissue surrounding the tumor may also be damaged. This is the usual cause of side effects, which are often short-lived and disappear after treatments are over. However, dependent on the site of the tumor, some "side effects" may last for years or may even be permanent. These might include memory impairment and personality changes, cataracts, heart problems, dental problems and infertility, according to Oncolink. An oncologist will discuss the risks versus benefits of a particular radiotherapy when offering treatment options.

Other Uses

• Some types of cancer are prone to metastasizing or spreading to other areas of the body, often to particular sites. In these cases, radiotherapy is sometimes employed prophylactically, meaning that it is administered to an area that does not contain cancer cells but is considered an area of risk for cancer spread. For some patients whose cancer has spread and causes pain in the bones and other areas, palliative radiotherapy may be employed to alleviate symptoms, according to the National Cancer Institute.