Retrospective Cohort Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Urol. Mar 24, 2016; 5(1): 45-52
Published online Mar 24, 2016. doi: 10.5410/wjcu.v5.i1.45
Adjuvant radiotherapy for pathologically advanced prostate cancer improves biochemical recurrence free survival compared to salvage radiotherapy
Robert H Blackwell, William Gange, Alexander M Kandabarow, Matthew M Harkenrider, Gopal N Gupta, Marcus L Quek, Robert C Flanigan
Robert H Blackwell, Gopal N Gupta, Marcus L Quek, Robert C Flanigan, Department of Urology, Loyola University Medical Center, Maywood, IL 60153, United States
William Gange, Alexander M Kandabarow, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, United States
Matthew M Harkenrider, Department of Radiation Oncology, Loyola University Medical Center, Maywood, IL 60153, United States
Author contributions: All the authors contributed to this paper.
Institutional review board statement: The study was approved by the institutional review board.
Informed consent statement: Given the retrospective nature of this study with minimal risk of harm, patient informed consent was waived by the institutional review board.
Conflict-of-interest statement: All of the authors report no conflict of interest (financial or otherwise) related to the manuscript.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Robert H Blackwell, MD, Department of Urology, Loyola University Medical Center, 2160 S, First Avenue, Building 54, Room 261, Maywood, IL 60153, United States. rblackwell@lumc.edu
Telephone: +1-708-2165100 Fax: +1-708-2161699
Received: September 2, 2015
Peer-review started: September 8, 2015
First decision: October 16, 2015
Revised: November 24, 2015
Accepted: January 8, 2016
Article in press: January 11, 2016
Published online: March 24, 2016
Processing time: 198 Days and 14 Hours
Abstract

AIM: To evaluate the long-term outcomes of patients receiving adjuvant and salvage radiotherapy following prostatectomy with adverse pathologic features and an undetectable prostate specific antigen (PSA).

METHODS: A retrospective review was performed of patients who received post-prostatectomy radiation at Loyola University Medical Center between 1992 and 2013. Adverse pathologic features (Gleason score ≥ 8, seminal vesicle invasion, extracapsular extension, pathologic T4 disease, and/or positive surgical margins) and an undetectable PSA following prostatectomy were required for inclusion. Adjuvant patients received therapy with an undetectable PSA, salvage patients following biochemical recurrence (BCR). Post-radiation BCR, overall survival, bone metastases, and initiation of hormonal therapy were assessed. Kaplan-Meier time-to-event analyses and stepwise Cox proportional hazards regression (HR) were performed.

RESULTS: Post-prostatectomy patients (n = 134) received either adjuvant (n = 47) or salvage (n = 87) radiation. Median age at radiotherapy (RT) was 63 years, and median follow-up was 53 mo. Five-year post-radiation BCR-free survival was 78% for adjuvant vs 50% salvage radiotherapy (SRT) (Logrank P = 0.001). Patients with radiation administered following a detectable PSA had an increased risk of BCR compared to undetectable: PSA > 0.0-0.2: HR = 4.1 (95%CI: 1.5-11.2; P = 0.005); PSA > 0.2-1.0: HR = 4.4 (95%CI: 1.6-11.9; P = 0.003); and PSA > 1.0: HR = 52 (95%CI: 12.9-210; P < 0.001). There was no demonstrable difference in rates of overall survival, bone metastases or utilization of hormonal therapy between adjuvant and SRT patients.

CONCLUSION: Adjuvant RT improves BCR-free survival compared to SRT in patients with adverse pathologic features and an undetectable post-prostatectomy PSA.

Keywords: Radiotherapy; Adjuvant; Radiotherapy; Salvage therapy; Recurrence; Prostatic neoplasms

Core tip: We evaluated the outcomes of patients who received post-prostatectomy radiotherapy (RT) who had adverse features on the pathologic specimen and an immediately undetectable prostate specific antigen (PSA) postoperatively. In this cohort of patients, those who received RT in the adjuvant therapy (e.g., while PSA remains undetectable) had an improved 5-year biochemical recurrence (BCR)-free survival of 78%, compared to 50% for patients receiving RT in the salvage setting (e.g., after the postoperative PSA has again become detectable). As such, adjuvant RT improves BCR free survival in post-prostatectomy patients with adverse pathologic features and an undetectable PSA compared to salvage RT.