Penile Cancer: Radiation Therapy

What is radiation therapy?

Radiation therapy uses high-energy radiation from X-rays or particles to kill cancer cells.

When might radiation therapy be used?

Radiation therapy can be part of the treatment for some penile cancers. There are several cases in which your healthcare provider may recommend this therapy:

• To treat some early stage cancers. Radiation might be used instead of surgery.

• To try to shrink the cancer before surgery. Radiation might be used along with chemotherapy. This combination may make the cancer easier to remove. When radiation is used before surgery, it’s called a neoadjuvant therapy.

• To treat cancer that has spread to nearby lymph nodes. Radiation therapy might be used after surgery to try to kill any remaining cancer cells.

• To ease symptoms caused by cancers that can't be treated with surgery, such as those that have spread to other organs.

To plan your entire treatment strategy, you will meet with a team of cancer specialists. This might include a urologist, radiation oncologist, and medical oncologist.

What happens during radiation therapy?

Radiation therapy for penile cancer can be given in two main ways: 

• External radiation. For this treatment, radiation is aimed at the cancer from a machine outside your body.

• Internal radiation (brachytherapy). For this treatment, a source of radiation is put into or right next to the cancer. This can be done using hollow needles put into the penis during an operation (interstitial radiation). Or the healthcare provider can put it in place using a plastic cylinder or mold over the penis.

A doctor who specializes in cancer and radiation is called a radiation oncologist. This doctor works with you to figure out the kind of radiation you need. This doctor also decides the dose and how long you need the therapy.

You can usually get radiation therapy as an outpatient in a hospital or a clinic. 

Getting ready for radiation

Before your first radiation treatment, you will have a session to decide exactly where on your body the radiation beam needs to be aimed. The process is called simulation. During this session, you may have imaging tests such as CT scans or MRI scan. This helps the doctors know the exact location of your tumor to better aim the radiation. Also at this session, you may have body molds made. These molds will help keep you from moving during the treatment. 

Then you will lie still on a table while a radiation therapist uses a machine to mark your treatment field. The field is the exact place on your body where the radiation will be aimed. Sometimes it’s called your port. The therapist may mark your skin with tiny dots of semi-permanent ink. The marks help make sure the radiation is aimed at the exact same place each time. 

On the days you get radiation

The standard treatment for external radiation is given 5 days a week for several weeks. On the days you get external radiation treatment, you will lie on a table while the machine is placed over you. You may have to wear a hospital gown. The experience is much like getting an X-ray, but it takes about 15 to 30 minutes to complete. You should plan on being there for about an hour.

At the start of each external radiation treatment session, a radiation therapist may place blocks or special shields on you. These protect parts of your body that don’t need to be exposed to radiation. The therapist then lines up the machine so that radiation is directed to the spot that was marked during the simulation. When you are ready, the therapist leaves the room and turns the machine on. You may hear whirring or clicking noises while the radiation is being given. During the session, you will be able to talk to the therapist over an intercom. You can’t feel radiation, so the process will be painless. Also, you will not be radioactive afterward.

Internal radiation therapy is usually given over several days in a row.

What to expect after radiation therapy

Because radiation affects normal cells as well as cancer cells, you may have some side effects from this treatment. The side effects from radiation are usually limited to the area being treated. Some people have few or no side effects. If you do have them, your doctor may change the dose of your radiation or how often you get the treatments. Or the doctor may stop treatment until the side effects are cleared up. Be sure to tell your doctor about any side effects you have.

These are some of the possible side effects of radiation to the penis:

• Skin irritation or changes in areas that get radiation. These can range from redness to skin peeling or oozing.

• Burning during urination

• Problems urinating

• Problems with erections

If radiation is aimed at nearby lymph nodes, side effects can include:

• Feeling tired

• Nausea

• Diarrhea

• Fluid buildup in the groin or your legs (lymphedema)

If you have any of the side effects, talk with your doctor or nurse about how to deal with them and how to know when they become serious. Usually these side effects go away a few weeks after you stop getting treatment.