According to research published in the September 21 issue of JAMA, for men who suffer from prostate cancer, the development of prediction models based on variables, such as pretreatment sexual function, patient characteristics and treatment factors, seems to be helpful in predicting whether they will have erectile function two years after receiving prostatectomy, external radiotherapy, or brachytherapy.

The researchers write: “Because most patients survive early-stage prostate cancer after treatment, health-related quality of life (HRQOL) outcomes have emerged as a major emphasis in treatment decisions. Erectile dysfunction is commonplace after prostate cancer treatment and has significant consequences for HRQOL. Among urinary, bowel, vitality, and sexual HRQOL domains – outcomes commonly impaired by prostate cancer treatment – sexual function in previously potent men is the most commonly impaired and is closely related to outcome satisfaction.” Information remains limited about how the combination of pretreatment patient characteristics and treatment factors connect to individualized sexual outcomes.

Mehrdad Alemozaffar, M.D., of Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, and colleagues carried out an investigation to find out if a man’s sexual outcome, following the most common therapies for early-stage prostate cancer, can be accurately predicted based on standard characteristics and treatment plans. Data from a academic multicenter cohort of men who were enrolled between 2003 to 2006, as well as pretreatment patient characteristics, sexual health-related quality of life, and treatment details, was used to create models that predicted erectile function two years after receiving treatment.

CaPSURE, a community-based cohort, enrolled 1,913 patients between 1995 to 2007 to externally approve the performance of the model. Patients in U.S. academic and community-based practices whose health-related quality of life was measured pretreatment (n = 1,201) underwent follow-up after prostatectomy, external radiotherapy, or brachytherapy for prostate cancer. For men that had completed two years of follow up (n = 1,027) their sexual outcomes were used to create models predicting erectile function, and were externally validated among 1,913 patients who participated in the community-based cohort.

They discovered that two years after the men had received treatment, 177 of 511 (35%) who underwent prostatectomy reported they were able to achieve functional erections suitable for intercourse. The equivalent figure was 37% (84 of 229) of men who had undergone external radiotherapy as their initial therapy, and 43% (107 of 247) of men who had undergone brachytherapy as their main treatment.

The investigators explain: “Pretreatment sexual HRQOL score, age, serum prostate-specific antigen level, race/ethnicity, body mass index, and intended treatment details were associated with functional erections 2 years after treatment. Multivariable logistic regression models predicting erectile function estimated 2-year function probabilities from as low as 10 percents or less to as high at 70 or greater depending on the individual’s pretreatment patient characteristics and treatment details. The models performed well in predicting erections in external validation among CaPSURE cohort patients.”

They conclude:

“We have developed clinically applicable models to predict recovery of erectile function following prostatectomy, external radiotherapy, or brachytherapy, for early-stage prostate cancer based on pretreatment sexual function, patient characteristics, and specific plan of treatment. External validation of this predictive model in a community-based cohort suggest that these findings are generalizable and may help physicians and patients to set personalized expectation regarding prospects for erectile function in the years following primary treatment for prostate cancer.”

Editorial: Helping Patients Make Better Personal Health Decisions

In an associated report, Michael J. Barry. M.D., of Massachusetts General Hospital, Boston, explains that routinely collecting objective measures of subjective phenomena from patients will need to become part of usual care instead of just research to enhance outcome prediction:

“More importantly, better ways of ensuring that patients are informed about their choices and invited to participate in making decisions need to be identified and disseminated. Outcomes data for all important options and outcomes need to be integrated in a useful synthesis for the broad spectrum of men facing this decision. A meta-analysis of randomized trials of patient decision aids to support a shared decision-making process for preference-sensitive conditions demonstrated better decision quality when these tools are used. For the most fateful decisions, coaches or navigators may be helpful and efficient as well.

The promise of patient-centered outcomes research will be realized not only when high-quality outcomes data are available for all common medical problems but also when patients are routinely informed and invited to participate in their health care decisions. To achieve this promise, patients must increasingly be encouraged to adopt the position of ‘no decision about me, without me.”

Written by Grace Rattue