Transitioning from conformal radiotherapy to intensity-modulated radiotherapy after radical prostatectomy: Clinical benefit, oncologic outcomes and incidence of gastrointestinal and urinary toxicities.

AIM: The purpose of this study was to review genitourinary (GU) and gastrointestinal (GI) toxicity associated with high-dose radiotherapy (RT) delivered with 3-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) or volumetric arc therapy (VMAT) following radical prostatectomy (RP). BACKGROUND: RP is a therapeutic option for the management of prostate cancer (PrCa). When assessing postoperative RT techniques for PrCa, the published literature focuses on patients treated with 2-dimensional conventional methods without reflecting the implementation of 3D-CRT, IMRT, or VMAT. MATERIALS AND METHODS: A total of 83 patients were included in this analysis; 30 patients received 3D-CRT, and 53 patients received IMRT/VMAT. Acute and late symptoms of the GU and lower GI tract were retrospectively graded according to the Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer radiation toxicity grading systems. The relapse failure-free rate and overall survival were also evaluated. RESULTS: The rate of acute GU toxicity was 9.4% vs. 13.3% for the IMRT/VMAT and 3D-CRT groups (p = 0.583). The 5-year actuarial rates of late GI toxicity for IMRT/VMAT and 3D-CRT treatments were 1.9% and 6.7%, respectively. The rate of late GU toxicity for the IMRT/VMAT and 3D-CRT treatment groups was 7.5% and 16.6%, respectively (p = 0.199). We found no association between acute or late toxicity and the RT technique in univariate and multivariate analyses. CONCLUSION: Postprostatectomy IMRT/VMAT and 3D-CRT achieved similar morbidity and cancer control outcomes. The clinical benefit of highly conformal techniques in this setting is unclear although formal analysis is needed.

Macroscopic locoregional relapse from prostate cancer: which role for salvage radiotherapy?

INTRODUCTION: Salvage radiotherapy (SRT) after radical prostatectomy for prostate cancer (PCa) is recommended as soon as PSA rises above 0.20 ng/ml, but many patients (pts) still experience local macroscopic relapse. The aim of this multicentric retrospective analysis was to evaluate the role of SRT in pts with macroscopic relapse. MATERIALS AND METHODS: From 2001 to 2016, 105 consecutive pts with macroscopic PCa relapse underwent SRT ± androgen deprivation therapy (ADT). Mean age was 72 years. At time of relapse, 29 pts had a PSA value < 1.0 ng/mL, 50 from 1.1 to 5, and 25 pts > 5. Before SRT, 23 pts had undergone 18F-choline PET and 15 pts pelvic MRI. Ninety-four pts had prostatic bed relapse only, and four nodal involvement. Fifty-one pts were previously submitted to first-line ADT, while 6 pts received ≥ 2 lines. RESULTS: At a median follow-up of 52 months, 89 pts were alive, while 16 were dead. Total RT dose to macroscopic lesions was > 70 Gy in 58 pts, 66-70 Gy in 43, and < 66 Gy in 4 pts. In 72 pts, target volume encompassed only the prostatic bed with sequential boost to macroscopic site; 33 pts received prophylactic pelvic RT. Ten-year overall survival was 76.1%, while distant metastasis-free survival was 73.3%. No grade 4-5 toxicities were found. CONCLUSIONS: SRT ± ADT for macroscopic relapse showed a favorable oncological outcome supporting its important role in this scenario. Data from this series suggest that SRT may either postpone ADT or improve results over ADT alone in appropriately selected pts.

Postoperative adjuvant and very early salvage radiotherapy after prostatectomy in high-risk prostate cancer patients can improve specific and overall survival.

PURPOSE: Adjuvant radiotherapy (ART) for biochemical relapse (BR) after radical prostatectomy (RP) showed increased disease-free survival (DFS) in three previous randomized trials. Retrospective phase II trials evaluated if early salvage RT (ESRT) is equivalent to ART. Our study aims to compare ART and ESRT to salvage RT. MATERIALS AND METHODS: We compared RP plus ART and ESRT versus SRT. Indication for RT was made by PSA determination after RP: ART when PSA ≤ 0.2 ng/ml, ESRT when PSA ≤ 0.3 after PSA rise from 0.0 to SRT PSA ≥ 0.3. The cause of death of each patients was analyzed, DFS, cause-specific survival (CSS) overall survival (OS) and metastasis-free survival (MFS) in relation to RT intention. RESULTS: Between 1993 and 2008, 204 patients with a median age of 65 years (44-75) were treated. The median follow-up was 160 months (28.1-273.3). At diagnosis, 89.7% had localized clinical stages and 90.2% had Gleason (G) ≤ 7. The median PSA was 10 (range 4-101). The postoperative G was ≥ 7 in 66.2%; 56.4% had ≥ 2 positive margins; 29.4% received ART, 20% ESRT and 59.3% SRT. The DFS for ART, ESRT and SRT was 74, 56 and 39% with significant differences between the three groups (p < 0.001). ART + ESRT were combined versus SRT; for the DFS, the significant differences (p < 0.001) remained 67% versus 39%. Positive margins, pT3 and pre-RT PSA were significant factors on multivariate analysis. The CSS in the ART + ESRT group was 92 vs. 78% in the SRT group (p < 0.05). OS was 69% in ART + ESRT vs. 57% in SRT (p < 0.05). MFS was 82.7% in ART + ESRT vs. 67.4% in SRT. CONCLUSIONS: In this study the ART + ESRT presented benefits versus SRT in DFS, CSS, OS and MFS.