Radiation Therapy

Radiation therapy is a cancer treatment that uses high energy x-rays or other types of radiation to kill cancer cells and there are generally two types of radiation therapy.

External Beam Radiation therapy uses a machine outside the body to send radiation towards the cancer. 

Brachytheraphy Radiation therapy is an internal type of radiation that uses a radioactive substance sealed in needles, seeds, wires or catheters that are placed directly into or near the cancer. 

Radiation therapy for testicular cancer is delivered by a carefully focused beam of radiation from a machine outside the body - external beam radiation. The treatment is much like getting an x-ray, but the radiation is more intense. The procedure itself is painless. Before your treatments start, the medical team will take careful measurements to determine the correct angles for aiming the radiation beams and the proper dose of radiation.  Each treatment lasts only a few minutes, but the setup time -- getting you into place for treatment -- usually takes longer.

In general, radiation therapy is mainly used for patients with seminoma, which is very sensitive to radiation. It does not seem to work well for non-seminomas. Sometimes it is used after an orchiectomy (the operation to remove the testicle) and is directed at the lymph nodes at the back of the abdomen (the retroperitoneal lymph nodes). This is to kill any tiny bits of cancer in those lymph nodes that can't be seen.  

Sources: cancer.gov & cancer.org