156 Development of Nomograms to Predict Erectile Function After Radiation Therapy

Abstract

Erectile dysfunction (ED) is a well-recognized complication of radiation therapy (RT) with numerous factors impacting upon erectile function (EF) preservation. Nomograms have been used as aids to counsel patients prior to radical prostatectomy. The aim of this study was to develop nomograms to predict the likelihood of EF recovery in patients following RT.(EFD) Study population included: men with PC who received RT; with baseline and follow-up IIEF EF domain scores, and PDE5i use documented. Parameters entered into the model were: patient age, number of vascular comorbidities (diabetes, hypertension, dyslipidemia, coronary artery disease, stroke, sleep apnea), treatment type (external beam, brachytherapy, or combination therapy), baseline EFD score, baseline PDE5i use (sometimes/regularly vs never), and cumulative PDE5i use. The predictive ability of these covariates on the respective outcomes were assessed with internal validation. Logistic regression was used to predict the probability that a patient will have EFD ≤10 (severe ED), and EFD ≥24 (functional erections) at 12, 24, and 36 months from baseline.