A small percentage of men in a prostate cancer study complained that their penis seemed shorter following treatment, with some saying that it interfered with intimate relationships and caused them to regret the type of treatment they chose.
Complaints were more common in men treated with radical prostatectomy (surgical removal of the prostate) or male hormone-blocking drugs combined with radiation therapy, according to the study by researchers from Dana-Farber/Brigham and Women's Cancer Center (DF/BWCC). No men reported a perceived shortening of their penis following radiation therapy alone.
The study's findings, which are being published in the January issue of the journal Urology, are based on surveys completed by physicians of 948 men treated for prostate cancer and who had suffered a recurrence of the disease.
Twenty-five men (2.63 percent of the group) complained of smaller penises after treatment - 3.73 percent for surgery, 2.67 percent for radiotherapy plus androgen deprivation therapy (ADT), and 0% for radiotherapy alone. Radiotherapy included both radiation administered by an external x-ray machine, and brachytherapy - the implantation of radioactive seeds directly into the prostate.
The scientific team, led by Paul Nguyen, MD, a radiation oncologist, and medical student Arti Parekh, said it is the first study to link men's perceptions of a reduction in penis size to lowered life satisfaction, problems in emotional relationships, and misgivings about the specific form of prostate cancer treatment they chose.
Nguyen said that the potential side effect of a smaller penis is well-known among physicians and surgeons, said Nguyen, "but it's almost never discussed with patients, so it can be very upsetting to some men when it occurs. Patients can deal with almost any side effect if they have some inkling ahead of time that they may happen."
The report's authors said physicians should discuss the possibility with their patients so that they can make more-informed treatment choices.
There were no direct measurements of penis size either before or after treatment, said the researchers. Nor did the patients' physicians specifically ask about this side effect; the issue was brought up by patients in conversations with their doctors. For this and other reasons, the authors of the new study suggest that the problem is likely more common than reported in the survey.
"Prostate cancer is one of the few cancers where patients have a choice of therapies, and because of the range of possible side effects, it can be a tough choice," said Nguyen. "This study says that when penile shortening does occur, it really does affect patients and their quality of life. It's something we should be discussing up front so that it will help reduce treatment regrets."