Radiation therapy for lung cancer

Radiation therapy may be employed as a treatment for both Non-Small Cell lung cancer and Small Cell lung cancer. Radiation therapy uses high-energy x-rays or other types of radiation to kill dividing cancer cells. Radiation therapy may be given as curative therapy, palliative therapy (using lower doses of radiation than with curative regimens) or as adjuvant therapy to surgery or chemotherapy. The radiation is either delivered externally, by using a machine that directs radiation toward the cancer, or internally through placement of radioactive substances in sealed containers within the area of the body where the tumor is localized.

Radiation therapy can be given if a person refuses surgery, if a tumor has spread to areas such as the lymph nodes or trachea making surgical removal impossible, or if a person has other conditions that make them too ill to undergo major surgery. Radiation therapy generally only shrinks a tumor or limits its growth when given as a sole therapy. Combining radiation therapy with chemotherapy can further increase the chances of survival when chemotherapy is administered. External radiation therapy can generally be carried out on an outpatient basis while internal radiation therapy requires a brief hospitalization. A person who has severe lung disease in addition to a lung cancer may not be able to receive radiotherapy to the lung.

For external radiation therapy, a process called simulation is necessary prior to treatment. Using CT scans, computers, and precise measurements, simulation maps out the exact location where the radiation will be delivered, called the treatment field or port. This process usually takes 30 minutes to two hours. The external radiation treatment itself generally is done over four or five days a week for several weeks.

Radiation therapy does not carry the risks of major surgery, but it can have unpleasant side effects including tiredness and lack of energy. A reduced white cell count (rendering a person more susceptible to infection) and low blood platelet levels (making blood clotting more difficult) can also occur with radiation therapy. If the digestive organs are in the field exposed to radiation, patients may experience nausea, vomiting, or diarrhea. Radiation therapy can irritate the skin in the area that is treated, but this irritation generally improves with time after treatment has ended.