Sexual function is one of the first things many men think about if they’re diagnosed with prostate cancer. However, it’s rarely the first, second, or even third thing they discuss with their partners and doctor. Occasionally, a patient will ask me about it, but many men get embarrassed and wait until their doctor brings it up – often when their partner is in a separate room.
Sex is a natural part of life for people in their 60s and 70s and increasingly has remained so with improved life expectancy and focus on active living. Men and their partners should be concerned about sexual function, or potency, after prostate cancer treatment. Changes in sexual health are a huge factor in quality of life after prostate cancer and should be considered when weighing your options.
In fact, it’s so important that my colleagues and I are leading the charge on a multicenter randomized clinical trial solely focused on preserving sexual potency after radiation therapy for prostate cancer. The Prostate Oncologic Therapy While Ensuring Neurovascular Conservation (POTEN-C) clinical trial involves stereotactic ablative radiotherapy, or SAbR, and a novel technique that we are hopeful will reduce patients’ risk for erectile dysfunction and other sexual side effects.
The role of sex in prostate cancer treatment decisions
Despite the stigma around discussing it, sex already is a major consideration in deciding how or whether to treat prostate cancer. Improved techniques, corrective procedures, and medications have reduced many of the urinary and bowel side effects historically associated with treatment, so sexual wellness can be the deciding factor for many men and their partners.
Radiation therapy delivered across many weeks to the entire prostate has long been a standard treatment in prostate cancer treatment but has made slow progress in adapting to advances in anatomic knowledge of the drivers of sexual function. These include improved imaging characterization of vessels and nerves involved in erectile function. In the late 1990s, nerve-sparing prostatectomy (prostate removal), in contrast, went mainstream. This procedure caught on due in large part to promises of preserving sexual potency, and it led to a significant shift in the number of men who chose surgery over radiation.
Unfortunately, despite these promises, men who choose prostatectomy still commonly lose potency and, in recent studies, continue to see a greater decrease in sexual function after surgery compared to other treatments. Thus, there is strong appetite to further improve sexual potency preservation, perhaps by adapting lessons learned from nerve-sparing surgery to other treatments.
Some men with low-risk or early-stage cancer can avoid the risk altogether by opting for active surveillance, or monitoring of the disease, rather than immediate treatment. However, one study found instances of prostate cancer spreading beyond the prostate (metastases) in more men who chose active surveillance than those who chose some form of immediate treatment, and up to half of men require therapy at some point regardless.
Preserving sexual function with SAbR
SAbR, also known as stereotactic body radiation therapy or SBRT, involves applying a precisely targeted dose of radiation directly to the tumor and sparing nearby healthy tissue, including the nerves and blood vessels involved in sexual function. It’s a convenient treatment that takes place over only five outpatient visits.
Hundreds of patients have been treated with SAbR at UT Southwestern over a period of more than 10 years, mostly funded by a U.S. Department of Defense grant. We published mature, prospective data using SAbR for low- and intermediate-risk prostate cancer showing impressive rates of potency preservation. In addition to SAbR’s benefits for sexual health, the treatment appears as effective as other options at eliminating prostate cancer, and it compares favorably in a number of additional areas, such as:
● Bowel function
● Fatigue and inconvenience of therapy
● Urinary incontinence
Many of the advances in SAbR that have made these milestones possible have been developed here at UT Southwestern, and it’s time for the next step: getting the word out about its remarkable potential benefits.
Sexual potency at the heart of the POTEN-C clinical trial
Despite the advances we’ve made across the board in prostate cancer care, preserving sexual function took a back seat to eliminating the disease for many doctors and researchers – until now. Because we know SAbR is effective in treating patients’ prostate cancer, our focus today can shift to sexual wellness.
I am leading the POTEN-C clinical trial, and it includes investigators at UT Southwestern and other top centers throughout the country. All of us will be working together to determine the effectiveness of a novel technique that involves the use of SpaceOAR, a gel that increases the space between the prostate and rectum during radiation therapy. This extra space might give enough room to reduce the risk of sexual side effects after treatment even more than what we’ve seen in the current generation of SAbR.
Importantly, this study is a collaborative effort with randomization and quality controls to stringently evaluate both the ability of this novel technique to improve sexual quality of life and whether it can be standardized across multiple centers. We have used the SpaceOAR for most of our patients over the past several years and presented the initial experience at national meetings. As of April 2018, we’ll start recruiting around 40 patients at UT Southwestern with prostate cancer to take part in the POTEN-C study, and we’ll eventually enroll 120 participants nationwide.
It’s natural and healthy to want an active sex life through your middle age and even well beyond. SAbR has the potential to become the future of prostate cancer care for many men, and we’re hopeful that we’ll be able to refine the treatment to preserve more patients’ sexual function.
If you’re newly diagnosed with prostate cancer or you’ve been on active surveillance, talk to your doctor about SAbR. Learn more about the POTEN-C trial on our site or at ClinicalTrials.gov.
