Radiation Therapy for Penile Cancer
Radiation therapy uses high-energy rays or particles to destroy cancer cells. It can be used in different situations for penile cancer:
- It can be used to treat some early-stage penile cancers instead of surgery.
- If the cancer has reached several lymph nodes, radiation may be used along with the surgical removal of lymph nodes to try to reduce the risk the cancer will come back.
- Radiation can be used for advanced cancer to try to slow the growth of the cancer or to relieve symptoms it causes.
For uncircumcised men who are going to get radiation to the penis, the foreskin is removed first. This is because radiation can cause swelling and constriction of the foreskin, which could lead to other problems.
There are 2 main ways to get radiation therapy.
External beam radiation therapy
The most common way to get radiation therapy is from carefully focused beams of radiation aimed at the tumor from a machine. The treatment is much like getting an x-ray, but the radiation is much stronger. The procedure itself is painless. Each treatment lasts only a few minutes, but the setup time – getting you into place for treatment – usually takes longer. Treatments are usually given 5 days a week for 6 weeks or so.
For brachytherapy, a radioactive source is placed into or right next to the penile tumor. The radiation travels only a short distance, so nearby healthy tissues don’t get much radiation. This type of treatment is done while you are in the hospital. There are 2 ways to get brachytherapy for penile cancer.
Interstitial radiation: In this method, hollow needles are first placed into the penis in the operating room. Then tiny pellets of radioactive materials are put into the needles to treat the tumor. The pellets are kept in place for several days while they release radiation. After the treatment is over, the needles are removed.
Plesiobrachytherapy: This type of brachytherapy puts the radiation source close to (but not into) the tumor. In this method, a plastic cylinder is placed around the penis, and then another cylinder with a radiation source is placed on top of the first cylinder. Another way to do this is to make a sponge-like mold of the penis and put the radioactive material into hollowed-out spaces in the mold. Treatment is usually given for several days in a row.
Possible side effects of radiation therapy
The main drawback of radiation therapy is that it can destroy or damage nearby healthy tissue along with the cancer cells. The skin in the treated area can become red and sensitive. There may be patches of skin that are oozing and tender. For some, the skin may even peel. For a while, you may feel a burning sensation when you urinate. The area may also swell for a time.
Patients treated with brachytherapy will find their side effects tend to be worse 1 to 2 weeks after the treatment is finished. If external beam radiation is used, the side effects tend to occur during treatment and then improve after radiation is stopped. Most symptoms go away over a couple of months. Over time, men treated with radiation may notice the skin of the penis has become darker or less elastic. Tiny web-like blood vessels (called telangiectasia) may be visible.
Some less common but more serious side effects can include:
- Some of the skin or tissue at the end of the penis might die (called necrosis).
- The urethra might become narrow from scar tissue (called stenosis), leading to problems urinating.
- An abnormal opening (fistula) might form between the urethra and skin, which could result in urine leaking out through the opening.
Radiation to the shaft of the penis might affect a man’s ability to have erections. But in cases where the tumor has not grown beyond the glans, radiation is directed only at the tip of the penis, so the ability to achieve erections should not be affected.
In many cases, the function and appearance of the penis gradually return to normal in the months and years after radiation therapy.
Possible side effects of radiation to the pelvic area and groin lymph nodes include tiredness, nausea, or diarrhea.
For more on radiation therapy to treat cancer, see our document Understanding Radiation Therapy: A Guide for Patients and Families.
Last Medical Review: March 30, 2015 Last Revised: February 9, 2016