ASTRO 2014: Precise radiotherapy saves more sexual function for prostate cancer patients

External beam radiotherapy (EBRT) was compared with a combination therapy of EBRT and brachytherapy to see which provided long-term sexual health for patients with prostate cancer. Results indicated that both treatment plans led to a high level of sexual function due to isolated radiation, according to a study presented during the 2014 annual meeting of the American Society for Radiation Oncology (ASTRO) being held Sept. 14-17 at the Moscone Center in San Francisco.

The study was conducted by Patrick W. McLaughlin, MD, director of radiation oncology at the University of Michigan Providence Cancer Institute in Novi, Mich., and colleagues. The researchers found that EBRT came out ahead due to the treatment's finely tuned radiation beam, which hones in the boundaries of radiation, sparing vital erectile tissues. The technology implements MRI guidance to point out critical blood vessels in the area.

“In the past, men with prostate cancer expected to pay a high toll in loss of quality of life to achieve cure and were willing to accept that as necessary,” said McLaughlin in the press release. “This study makes it clear that even with combination radiation protocols, which are capable of curing the majority of prostate cancers more than 90 percent of the time, avoidance of critical adjacent tissues, such as vessel-sparing, makes cure and quality of life an achievable goal for many men.”

In this study, 91 men with prostate cancer who underwent MRI-guided EBRT self-reported outcomes. Of these, 42 men had only EBRT and 49 had a combination with I-125 permanently implanted brachytherapy. Androgen deprivation therapy was not administered. Patients reported sexual function on two scales: the International Index of Erectile Function (IIEF) scale and a brief questionnaire about sexual activity and the use of aids and medications. The study looked at baseline and follow-up at two years and five years after therapy.

Sexual performance was lower on the IIEF scale than the questionnaire. Average follow-up IIEF scores at two years for those who received EBRT alone were 16.5 while combination patients reported 20.8. At five years, those numbers dropped slightly to 15.4 and 16.9, respectively.

The questionnaire indicated good preservation of sexual function with MRI-planned vessel-sparing treatment, even in patients who received combination therapy. A total of 78.6 percent, or 33 out of 42, patients who received EBRT, and 91.8 percent, or 45 out of 49, of patients who received combination therapy, reported sexual activity with or without aids.