Radiation Therapy for Testicular Cancer

When Is Radiation Therapy Used for Testicular Cancer?

External beam radiation device.

WHAT IS RADIATION THERAPY?

Radiation therapy uses the emission of subatomic particles to dislodge electrons from atoms which produces a charge. These charged atoms are known as ions and this process is known as ionization. Ionization damages the DNA of cells and results in cell death. In this manner, it can be used to treat cancerous tumors, including certain types of testicular cancer. In the United States, doses of radiation are typically measured in units known as gray (abbreviated Gy).

WHEN IS IT USED FOR TESTICULAR CANCER?

Radiation therapy is used in a specific type of testicular cancer known as seminoma, which tends to be more sensitive to radiation than other testicular cancer subtypes. Given this sensitivity, seminoma can be, and typically is, cured following radiation treatment. Radiation is utilized in specific stages of seminoma. 

In stage I seminoma, there is no known/visible cancer outside of the testicle. However, it is possible that microscopic amounts of cancer cells have traveled undetected to a series of lymph nodes behind the bowel known as retroperitoneal lymph nodes. Radiation therapy can be done as a safeguard to kill any cancer cells that may have unknowingly spread to the lymph nodes. This is not routinely done, because even if spread to lymph nodes is discovered later without radiation, it is still highly curable with radiation or chemotherapy.

In stage II seminoma, unless the involved nodes are too enlarged, radiation therapy is oftentimes the preferred intervention to treat/cure the cancer.

Chemotherapy is also an alternative option.

HOW IS IT USED TO TREAT/CURE TESTICULAR CANCER?

Radiation therapy can start as soon as adequate healing has taken place from surgery (surgical removal of the cancerous testicle happens first). The person receiving the radiation initially comes in for a planning session known as simulation.

 The total dose of radiation is determined and is typically 20.0 Gy for stage I disease and 30.0 Gy for stage II disease.  The total dose is divided and typically given 5 times a week in 2 Gy fractions at a time. This means is should take 2 or 3 weeks depending on the exact stage and dose of radiation.

The area affected by radiation is referred to as a field. The field encompasses the lower abdomen/pelvis and is meant to target the lymph nodes while limiting radiation to surrounding structures, such as the kidneys.

The individual receiving the radiation lies down on a table with the radiation emitter located above. A shield is used to protect the remaining testicle. Oftentimes a towel is placed between the legs to maintain correct positioning. Receiving the radiation only takes several moments once the person is in place. The radiation itself is imperceptible: no light is seen and nothing is felt, similar to having an x-ray performed.

WHAT ARE THE SIDE EFFECTS FROM RADIATION THERAPY?

Side effects from radiation therapy can happen immediately or occur years down the road.

Effects may be temporary or permanent. While undergoing radiation therapy it is not uncommon to experience fatigue, nausea, mild bone marrow suppression as well as mild tanning of the treated skin. There is an increased risk of sterility, which has been minimized by modern treatment protocols. Regardless, it is prudent to consider sperm banking prior to treatment. The risk for a secondary cancer years down the road is increased. The risk is highest for solid tumor cancers such as the bladder, stomach, pancreas and kidney. The risk for blood cancers, like leukemia, is not very high, but is higher than the general population. 

WHO SHOULD NOT HAVE RADIATION THERAPY?

Radiation therapy is not for everyone. Those with a congenital kidney defect known as horseshoe kidney should not have radiation because it can potentially increase the risk for kidney cancer. Those with inflammatory bowel disorders (ulcerative colitis, Crohn's disease etc.) should avoid radiation as it can worsen their condition. Radiation should be avoided in patients who have had prior radiation therapy.

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