TY - JOUR
T1 - A Prospective Phase 2 Trial of Transperineal Ultrasound-Guided Brachytherapy for Locally Recurrent Prostate Cancer After External Beam Radiation Therapy (NRG Oncology/RTOG-0526)
AU - Crook, Juanita M.
AU - Zhang, Peixin
AU - Pisansky, Thomas M.
AU - Trabulsi, Edouard J.
AU - Amin, Mahul B.
AU - Bice, William
AU - Morton, Gerard
AU - Pervez, Nadeem
AU - Vigneault, Eric
AU - Catton, Charles
AU - Michalski, Jeff
AU - Roach, Mack
AU - Beyer, David
AU - Jani, Ashesh
AU - Horwitz, Eric
AU - Donavanik, Viroon
AU - Sandler, Howard
N1 - Funding Information:
The trial was supported by grants U10CA180868 (NRG Oncology Operations) and U10CA180822 (NRG Oncology SDMC) and by the National Cancer Institute. The Clinicaltrials.gov registry number is NCT00450411.As single-center reports demonstrated efficacy of salvage low-dose-rate (LDR) brachytherapy, the Radiation Therapy Oncology Group (RTOG) undertook a prospective phase 2 trial in 2005 to investigate late toxicity. 13,14 The trial was supported by grants U10CA180868 (NRG Oncology Operations), U10CA180822 (NRG Oncology SDMC), and the National Cancer Institute. The Clinicaltrials.gov registry number is NCT00450411. We report the primary endpoint: treatment-related, grade 3 or higher, late gastrointestinal (GI) or genitourinary (GU) adverse events (AEs).
Publisher Copyright:
© 2018 Elsevier Inc.
PY - 2019/2/1
Y1 - 2019/2/1
N2 - Purpose: Only retrospective data are available for low-dose-rate (LDR) salvage prostate brachytherapy for local recurrence after external beam radiation therapy (EBRT). The primary objective of this prospective phase 2 trial (NCT00450411) was to evaluate late gastrointestinal and genitourinary adverse events (AEs) after salvage LDR brachytherapy. Methods and Materials: Eligible patients had low- or intermediate-risk prostate cancer before EBRT and biopsy-proven recurrence >30 months after EBRT, with prostate-specific antigen levels <10 ng/mL and no regional/distant disease. The primary endpoint was grade 3 or higher late treatment-related gastrointestinal or genitourinary AEs occurring 9 to 24 months after brachytherapy. These AEs were projected to be ≤10%, with ≥20% considered unacceptable. All events were graded with National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. Multivariate analyses investigated associations of pretreatment or treatment variables with AEs. Results: One hundred patients from 20 centers were registered from May 2007 to January 2014. The 92 analyzable patients had a median follow-up of 54 months (range, 4-97) and a median age of 70 years (interquartile range [IQR], 65-74). The initial Gleason score was 7 in 48% of patients. The median dose of EBRT was 74 Gy (IQR, 70-76) at a median interval of 85 months previously (IQR, 60-119). Only 16% had androgen deprivation at study entry. Twelve patients (14%) had late grade 3 gastrointestinal/genitourinary AEs, with no treatment-related grade 4 or 5 AEs. No pretreatment variable predicted late AEs, including prior EBRT dose and elapsed interval. Higher V100 (percentage of prostate enclosed by prescription isodose) predicted both occurrence of late AEs (odds ratio, 1.24; 95% confidence interval, 1.02-1.52; P =.03) and earlier time to first occurrence (hazard ratio, 1.18; 95% CI, 1.03-1.34; P =.02). Conclusions: This prospective multicenter trial reports outcomes of salvage LDR brachytherapy for post-EBRT recurrence. The rate of late grade 3 AEs did not exceed the unacceptable threshold. The only factor predictive of late AEs was implant dosimetry reflected by V100. Efficacy outcomes will be reported at a minimum of 5-year follow-up.
AB - Purpose: Only retrospective data are available for low-dose-rate (LDR) salvage prostate brachytherapy for local recurrence after external beam radiation therapy (EBRT). The primary objective of this prospective phase 2 trial (NCT00450411) was to evaluate late gastrointestinal and genitourinary adverse events (AEs) after salvage LDR brachytherapy. Methods and Materials: Eligible patients had low- or intermediate-risk prostate cancer before EBRT and biopsy-proven recurrence >30 months after EBRT, with prostate-specific antigen levels <10 ng/mL and no regional/distant disease. The primary endpoint was grade 3 or higher late treatment-related gastrointestinal or genitourinary AEs occurring 9 to 24 months after brachytherapy. These AEs were projected to be ≤10%, with ≥20% considered unacceptable. All events were graded with National Cancer Institute Common Terminology Criteria for Adverse Events version 3.0. Multivariate analyses investigated associations of pretreatment or treatment variables with AEs. Results: One hundred patients from 20 centers were registered from May 2007 to January 2014. The 92 analyzable patients had a median follow-up of 54 months (range, 4-97) and a median age of 70 years (interquartile range [IQR], 65-74). The initial Gleason score was 7 in 48% of patients. The median dose of EBRT was 74 Gy (IQR, 70-76) at a median interval of 85 months previously (IQR, 60-119). Only 16% had androgen deprivation at study entry. Twelve patients (14%) had late grade 3 gastrointestinal/genitourinary AEs, with no treatment-related grade 4 or 5 AEs. No pretreatment variable predicted late AEs, including prior EBRT dose and elapsed interval. Higher V100 (percentage of prostate enclosed by prescription isodose) predicted both occurrence of late AEs (odds ratio, 1.24; 95% confidence interval, 1.02-1.52; P =.03) and earlier time to first occurrence (hazard ratio, 1.18; 95% CI, 1.03-1.34; P =.02). Conclusions: This prospective multicenter trial reports outcomes of salvage LDR brachytherapy for post-EBRT recurrence. The rate of late grade 3 AEs did not exceed the unacceptable threshold. The only factor predictive of late AEs was implant dosimetry reflected by V100. Efficacy outcomes will be reported at a minimum of 5-year follow-up.
UR - http://www.scopus.com/inward/record.url?scp=85059587262&partnerID=8YFLogxK
U2 - 10.1016/j.ijrobp.2018.09.039
DO - 10.1016/j.ijrobp.2018.09.039
M3 - Article
C2 - 30312717
AN - SCOPUS:85059587262
VL - 103
SP - 335
EP - 343
JO - International Journal of Radiation Oncology Biology Physics
JF - International Journal of Radiation Oncology Biology Physics
SN - 0360-3016
IS - 2
ER -