Management of localized prostate cancer aims at achieving the trifecta of cancer control, urinary continence, and preservation of erectile function. With optimal cancer control being achieved through most interventions, the focus is currently on the other two outcomes that form a major quality of life issue in these men who are expected to be cured of their primary disease.
Pre-treatment prediction of post-intervention erectile function would be useful in patient counseling. The Prostate Cancer Outcomes and Satisfaction with Treatment Quality Assessment (PROSTQA) is a prospective, multicenter study that in 2003, began enrolling men with localized prostate cancer scheduled for definitive therapy with radical prostatectomy, external beam radiotherapy or brachytherapy. Apart from baseline patient data, the investigators recorded details of the treatment planned including nerve sparing surgery, hormonal therapy and radiation protocols. Post-intervention patient reported outcomes were recorded by third-party interviews using validated questionnaires.
In a recent trial by Alemozaffar and colleagues published in JAMA, the study investigators reported patient assessed erectile function in 1027 men who had completed 24 months after intervention. A significant increase in erectile dysfunction was reported in all 3 intervention groups: 63% vs 28% in radical prostatectomy, 63% vs 47% in the external radiotherapy group and 57% vs 33% in the brachytherapy group. Among men who were potent prior to intervention, 52% had ED after intervention; 60% in the prostatectomy group, 42% in the external radiotherapy group and 37% in the brachytherapy group. The authors were able to generate models that accurately predicted the occurrence of erectile dysfunction in the three treatment strategies. Models such as this one suggest that stratification by pretreatment patient characteristics and treatment details enables prediction of erectile function 2 years after prostatectomy, external radiotherapy, or brachytherapy for prostate cancer. While such a model cannot be used to judge superiority of one treatment strategy over another, it does aid in counseling patients about their individual outcome probabilities.
Alemozaffar M, Regan MM, Cooperberg MR, Wei JT, et al. Prediction of erectile function following treatment for prostate cancer. JAMA 2011;306:1205-14.