Besides surgery and chemotherapy, radiation therapy is also considered as one of the vital method of cancer treatment. Usually about 50 percent of cancer patient are given radiotherapy at some or the other stage of their treatment. Mostly it is used for the treatment of localized tumors like cancer of brain, skin, and cervix and so on. 
 
Nowadays proton or Cyberknife cancer radiation therapy is gaining popularity, as they are technologically advanced form, causing less harm to normal tissues. These technologies intensely focus on the tumor cells. 
 
Principles of radiation therapy
 
In radiation therapy gi cancer is treated with the help of ionizing radiation. It works by damaging the DNA of tumor cells, stopping their division and growth. Radiation is usually given with an intention to destroy tumor and treating disease. When this radiation is directed towards tumor cells it is not possible to prevent the normal cells surrounding it from damage. The aim of radiation therapy to intensely affect the cancer cells minimizing the exposure to normal cells. 
 
For a solid tumor single therapy cannot provide complement treatment to a patient. Thus radiotherapy is provided with a combination of surgery or chemotherapy, as to make the treatment successful. Even sometimes Cancer Radiation Therapy is given to relieve symptoms like pain or seizures. This procedure is known as palliative treatment.
 
Types of radiation therapy
 
There are several types of radiation therapy available which are provided depending on the cancer. 
 
1.External beam radiation therapy: In this type of therapy radiation beam is created and targeted on the tumor cells. Radiation mainly covers the cancer cells and minimizes the dose to normal cells. It is essential to give radiation in fractions rather going for single dose. This procedure of fractionated exposure gives time to normal cells to repair themselves, protecting them from injury.
2.Proton beam radiation therapy: Nowadays it is the most precise and sophisticated form of external beam therapy available. It is more advantageous to use this therapy over X-rays because of its ability to intensely focus the beams of radiation directly on the tumor cells and minimizing the dose on normal cells. This technique leads to less side effects and increase in survival rates. 
 
3.Intensity modulated radiation therapy: It is also a high power radiation therapy creating a shaped beam, directly delivering high doses of radiation on the affected cells and thus lowering the effect on normal tissues. These days it has been successfully used to treat many types of cancer such as prostate, nasopharyngeal and cervical. 
 
You can find several popular Lung Cancer Treatment involving radiation therapy for treating cancer patients. Along with radiation therapy it is also vital to combine it with other treatments like surgery and chemotherapy as to cure the disease completely. If even a minute cancer cell is left untreated it may lead to occurrence of future cancer.