RESUMEN
Androgen deprivation therapy (ADT) is a mainstay of treatment for metastatic prostate cancer, while additional salvage radiotherapy may offer prolonged remission for patients with regional node relapses. We report 5-yr outcomes from OLIGOPELVIS (GETUG-P07), an open-label phase 2 trial assessing long-term outcomes and patterns of relapse after 6-mo ADT and elective nodal radiotherapy (ENRT) in men with pelvic nodal oligorecurrence (<6 lesions) of prostate cancer. Progression was defined as two consecutive prostate-specific antigen (PSA) levels above the level at inclusion and/or clinical progression according to Response Evaluation Criteria in Solid Tumors v1.1 and/or death from any cause. Sixty-seven patients were recruited. Median follow-up was 6.1 yr (95% confidence interval 5.9-6.3). Rates of grade 2+ toxicities among patients without progression at 3, 4, and 5 yr were 15%, 9%, and 4% for genitourinary toxicities, and 2%, 3%, and 4% for gastrointestinal toxicities, respectively. The 5-yr progression-free, biochemical relapse-free, and ADT-free survival rates were 39%, 31%, and 64%, respectively. In total, 45 patients experienced progression, which was PSA-only progression in seven cases. Among the other 38 patients, local clinical progression occurred in 18%, progression to N1 stage in 29%, to M1a stage in 50%, to M1b stage in 32%, and to M1c stage in 11%. Finally, combined ENRT and ADT appeared to prolong tumor control with limited toxicity. At 5 yr, one-third of the patients had not experienced biochemical relapse. The major site of relapse was the para-aortic lymph nodes. PATIENT SUMMARY: We evaluated long-term results for high-dose radiotherapy in patients with recurrence of prostate cancer in pelvic lymph nodes. We found that this treatment provided prolonged tumor control without significant toxicity. One-third of the patients were still in complete remission after 5 years.
RESUMEN
BACKGROUND: Oligorecurrent pelvic nodal relapse in prostatic cancer is a challenge for regional salvage treatments. Androgen depriving therapies (ADTs) are a mainstay in metastatic prostate cancer, and salvage pelvic radiotherapy may offer long ADT-free intervals for patients harboring regional nodal relapses. OBJECTIVE: To assess the efficacy of the combination of ADT and salvage radiotherapy in men with oligorecurrent pelvic node relapses of prostate cancer. DESIGN, SETTING, AND PARTICIPANTS: We performed an open-label, phase II trial of combined high-dose intensity-modulated radiotherapy and ADT (6 mo) in oligorecurrent (five or fewer) pelvic node relapses in prostate cancer, detected by fluorocholine positron-emission tomography computed tomography imaging. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was 2-yr progression-free survival defined as two consecutive prostate-specific antigen levels above the level at inclusion and/or clinical evidence of progression as per RECIST 1.1 and/or death from any cause. RESULTS AND LIMITATIONS: Between August 2014 and July 2016, 67 patients were recruited in 15 centers. Half of the patients had received prior prostatic irradiation. The median age was 67.7 yr. After a median follow-up of 49.4 mo, 2- and 3-yr progression-free survival rates were 81% and 58%, respectively. Median progression-free survival was 45.3 mo. The median biochemical relapse-free survival (BRFS) was 25.9 mo. At 2 and 3 yr, the BRFS rates were 58% and 46%, respectively. Grade 2 + 2-yr genitourinary and gastrointestinal toxicities were 10% and 2%, respectively. CONCLUSIONS: Combined high-dose salvage pelvic radiotherapy and ADT appeared to prolong tumor control in oligorecurrent pelvic node relapses in prostate cancer with limited toxicity. After 3 yr, nearly half of patients were in complete remission. Our study showed initial evidence of benefit, but a randomized trial is required to confirm this result. PATIENT SUMMARY: In this report, we looked at the outcomes of combined high-dose salvage pelvic radiotherapy and 6-mo-long hormone therapy in oligorecurrent pelvic nodal relapse in prostatic cancer. We found that 46% of patients presenting with oligorecurrent pelvic node relapses in prostate cancer were in complete remission after 3 yr following combined treatment at the cost of limited toxicity.
