Web-Based Tool Helps Predict Functional Outcomes After Prostate Cancer Treatment

A web-based tool can help predict functional outcomes for 5 years after treatment of localized prostate cancer with radical prostatectomy (RP), intensity-modulated radiation therapy (RT), or active surveillance, researchers say.

The tool, "A prediction model for domain scores for prostate cancer patients," is available at https://statez.shinyapps.io/PCDSPred/.

"This personalized tool incorporates age, race, prostate specific-antigen, biopsy grade, and pre-treatment baseline function to individualize the results," Dr. Aaron Laviana of Vanderbilt University Medical Center in Nashville told Reuters Health by email. "Functional outcomes look at erectile function, urinary incontinence, urinary irritative symptoms, and bowel and hormonal function using the EPIC-26 questionnaire."

Dr. Laviana and colleagues analyzed data from US cancer registries on men diagnosed with localized prostate cancer in 2011-2012. The population was diverse with respect to age, race, and disease severity.

As reported in JAMA Oncology, 2,563 men completed a baseline survey and at least one subsequent survey (94.9%). Specifically, survey response rates were 89% at 6 months, 86% at 12 months, 78% at 36 months, and 70% at 60 months; 1,755 patients (68.4%) completed all surveys at every time point.

Twenty-six percent of men in the active surveillance cohort eventually underwent RP or EBRT, but were categorized as active surveillance.

The prediction models achieved a bias-corrected R-squared value of 0.386, indicating that the model explained 38.6% of the total variation of the domain scores for sexual function; values were 0.232 for the urinary incontinence domain; 0.183 for urinary irritative; 0.214 for bowel; and 0.309 for hormonal.

The authors state, "...Given the favorable long-term survival seen for localized prostate cancer, understanding patient-specific harms from treatment is critical, as is being able to assimilate this into a tool that is not overbearing to complete. Ideally, the more information we put into a model, the more reflective it is of an expected outcome, but after a certain point, the majority of the variation can be explained by the input provided."

Dr. Laviana said, "We hope this tool will be used along with our article published in the Journal of Urology in December 2019 in order to truly understand what the EPIC-26 scores mean. For example, if you score an 80 in sexual function, what is your probability of obtaining an erection sufficient for intercourse? Understanding these numbers is essential for knowing what to expect with treatment."

"It is important to note that this tool will not guarantee a certain functional outcome after treatment as there are always individual circumstances that may arise with treatment," he added. "Our next step involves externally validating this tool with other large datasets."

Dr. Yung Lyou, a medical oncologist at City of Hope in Duarte, California, tried the tool, and while he thinks it's a good "first step," he has some reservations. "I see difficulty in our 70- to 80-year-old-patient using this computer app. It will give you an error message if you forget to fill in all 30-40 questions but not tell you what information is missing," so you have to scroll through to find out, he commented in an email to Reuters Health.

"Additionally, for the busy clinician, it takes about an extra 10-15 minutes to interview the patient and fill in all the information," he said. Plus, the differences between "good" versus "very good" and "poor" versus "very poor" are not clear.

"It would be most useful if it had fewer questions, and ones that were more objective," he said.

Further, he added, "the results... give you predicted percentages that you have to interpret. (The app) doesn't offer the easy-to-understand 'yes' or 'no' answers most patients or doctors would like on what is the better mode of treatment."

That said, he concluded, "I would say that this tool is a good first step in helping provide a framework for incorporating quality-of-life symptoms into the treatment-decision process."

—Marilynn Larkin

Source