Nomograms for Metastasis-Free and Overall Survival for Pathologically Node Positive Prostate Cancer Patients Treated With or Without Radiation Therapy Plus Short-Term ADT.

Purpose/

Objectives: We aimed to develop nomograms to predict the risk reduction for metastasis and death in pathologically node-positive (pN +) prostate cancer patients treated with or without radiation therapy (RT). Materials/

Methods: From a prospectively gathered institutional database, we identified patients with pN + M0 prostate cancer after surgery. We evaluated several regression models of known or suspected clinical-pathologic covariates and selected the model with the highest Harrell's concordance-index (c-index) and clinical utility to prognosticate metastasis for inclusion in a nomogram. Covariates in the final, competing-risk adjusted, metastasis model included PSA nadir after surgery, pathologic T-stage, margin status, Gleason score (GS), number of positive lymph nodes, and use of postoperative radiotherapy combined with androgen deprivation therapy (RT + ADT). The overall survival model also included Charlson comorbidity score and age.

Results: 336 pN + men with a mean age of 64.9 years and a median follow-up of 4.1 years who had a radical prostatectomy were included in the analysis. 83 men were recommended RT + ADT, of whom 4% refused the ADT and received RT alone. C-index was 0.85 and 0.71 for the MFS and OS models, respectively. On multivariable analysis (MVA) adjusted for competing risks, RT + ADT significantly improved MFS (HR=0.70 P = < .01) with number of nodes positive, GS 8-10, PSA nadir > 1 ng/mL, and pT3b prognostic for metastasis. MVA for OS demonstrates RT+ADT improves survival (HR=0.40, P = .02), with GS8-10 and PSA nadir > 1.0 prognostic for death.

Conclusion: We developed predictive nomograms for patients with pN+ prostate cancer following radical prostatectomy. These models can discretely quantify an individual's risk of metastasis or death with and without post-prostatectomy radiotherapy.