“We are still following patients from the initial cohort,” reported Martin G. Sanda, MD, principal investigator of the study published in JAMA, “Prediction of Erectile Function Following Treatment for Prostate Cancer.” At a median follow-up now of about 6 years, “there is evidence that there might be some additional recovery of erections from year 2 to 3 in patients who underwent prostatectomy,” he said. “Conversely, with brachytherapy there might be continued deterioration of erectile functioning.”
An extension study is “looking with greater granularity at the extent of planned nerve-sparing prostatectomy,” Dr. Sanda added. While the recently reported study compared only nerve-sparing vs no nerve-sparing, the extension study will separate out complete bilateral nerve-sparing from less complete nerve-sparing. Another focus of the extension study will be “whether robotically assisted laparoscopic prostatectomy changes the observed vs predicted outcome,” Dr. Sanda said.
Practitioner-specific Differences
A still unanswered question is, to what extent do practitioner-specific differences affect the outcome? “In the case of surgery, surgeons might not just have different skill sets— they may have different management strategies, for achieving that balance between optimal cancer resection and optimal function preservation,” Dr. Sanda said. “That same question holds for radiation treatment, be it external-beam radiotherapy or seed-implant treatment,” he continued. “Whether variations between practitioners actually translate into significant variations in outcome in terms of sexuality is not yet known, but we are planning to look into that.” Those studies will involve both the original and extension cohorts.
The Radiation Therapy Oncology Group (RTOG) has studies nearing completion of accrual “that will provide some helpful information in a randomized setting on the radiation side,” Dr. Sanda noted. “Specifically RTOG 0232 is randomly assigning patients to brachytherapy alone or brachytherapy combined with external-beam irradiation. That study is evaluating cancer control as well as quality-of-life endpoints. I think it is going to be an important study, and hopefully its results will be available in the next couple of years.”■
Disclosure: Dr. Sanda reported no potential conflicts of interest.