Prostate-Only Versus Whole-Pelvic Radiation Therapy in High-Risk and Very High-Risk Prostate Cancer (POP-RT): Outcomes From Phase III Randomized Controlled Trial

Abstract

PURPOSE We report the clinical outcomes of a randomized trial comparing prophylactic whole-pelvic nodal radiotherapy to prostate-only radiotherapy (PORT) in high-risk prostate cancer. METHODS This phase III, single center, randomized controlled trial enrolled eligible patients undergoing radical radiotherapy for node-negative prostate adenocarcinoma, with estimated nodal risk ≥ 20%. Randomization was 1:1 to PORT (68 Gy/25# to prostate) or whole-pelvic radiotherapy (WPRT, 68 Gy/25# to prostate, 50 Gy/25# to pelvic nodes, including common iliac) using computerized stratified block randomization, stratified by Gleason score, type of androgen deprivation, prostate-specific antigen at diagnosis, and prior transurethral resection of the prostate. All patients received image-guided, intensity-modulated radiotherapy and minimum 2 years of androgen deprivation therapy. The primary end point was 5-year biochemical failure-free survival (BFFS), and secondary end points were disease-free survival (DFS) and overall survival (OS). RESULTS From November 2011 to August 2017, a total of 224 patients were randomly assigned (PORT = 114, WPRT = 110). At a median follow-up of 68 months, 36 biochemical failures (PORT = 25, WPRT = 7) and 24 deaths (PORT = 13, WPRT = 11) were recorded. Five-year BFFS was 95.0% (95% CI, 88.4 to 97.9) with WPRT versus 81.2% (95% CI, 71.6 to 87.8) with PORT, with an unadjusted hazard ratio (HR) of 0.23 (95% CI, 0.10 to 0.52; P < .0001). WPRT also showed higher 5-year DFS (89.5% v 77.2%; HR, 0.40; 95% CI, 0.22 to 0.73; P = .002), but 5-year OS did not appear to differ (92.5% v 90.8%; HR, 0.92; 95% CI, 0.41 to 2.05; P = .83). Distant metastasis-free survival was also higher with WPRT (95.9% v 89.2%; HR, 0.35; 95% CI, 0.15 to 0.82; P = .01). Benefit in BFFS and DFS was maintained across prognostic subgroups. CONCLUSION Prophylactic pelvic irradiation for high-risk, locally advanced prostate cancer improved BFFS and DFS as compared with PORT, but OS did not appear to differ.

How Has Prostate Cancer Radiotherapy Changed in Italy between 2004 and 2011? An Analysis of the National Patterns-Of-Practice (POP) Database by the Uro-Oncology Study Group of the Italian Society of Radiotherapy and Clinical Oncology (AIRO)

“…These data reflect the lack of clear evidence for a clinical benefit of prophylactic pelvic irradiation (PPI), even in the setting of high-risk patients. An ongoing multicenter study (PROEPI) promoted by the AIRO Uro-Oncology Study Group will likely result in additional insight in this scenario; given also that data from a randomized Phase III clinical trial favoring the use of PPI in high and very high risk patients have been recently published [ 29 ].…”

A Review on the Current Treatment Paradigm in High-Risk Prostate Cancer

“…Importantly, approximately 80% of patients enrolled underwent PSMA PET-CT for initial staging. At a median follow-up of 68 months, whole-pelvis radiotherapy improved 5-year biochemical progression-free survival (HR: 0.23, 95% CI: 0.10-0.52), 5-year disease-free survival (HR: 0.40, 95% CI: 0.22-0.73), and metastasis-free survival (HR: 0.35, 95% CI: 0.15-0.82) compared to prostateonly radiotherapy, but did not impact overall survival (HR: 0.92, 95% CI: 0.41-2.05) [31]. However, the follow-up in these two studies is still premature in terms of detecting any overall survival difference.…”

A hidden Markov model for lymphatic tumor progression in the head and neck

“…In radiation therapy and surgical treatment of most cancer types it is the aim to irradiate or resect as much malign tissue as possible, including elective treatment of regions of possible microscopic spread, to increase the patient’s probability of cure 1 , 2 . Many cancer types spread though the lymphatic system and metastasize in regional lymph nodes 3 – 8 .…”