Salvage Low-Dose-Rate Prostate Brachytherapy: Clinical Outcomes of a Phase 2 Trial for Local Recurrence after External Beam Radiation Therapy (NRG Oncology/RTOG 0526).
Int J Radiat Oncol Biol Phys
; 112(5): 1115-1122, 2022 04 01.
Article
en En
| MEDLINE
| ID: mdl-34740768
ABSTRACT
PURPOSE:
We report efficacy of a prospective phase 2 trial (NCT00450411) of salvage low-dose-rate (LDR) prostate brachytherapy (BT) for local failure (LF) after prior external beam radiation therapy (EBRT) with minimum 5-years' follow-up. METHODS AND MATERIALS Eligible patients had low/intermediate risk prostate cancer (PCa) before EBRT and biopsy-proven LF >30 months after EBRT, with prostate-specific antigen <10 ng/mL and no regional/distant disease. The primary endpoint, late gastrointestinal and genitourinary adverse events (Common Terminology Criteria for Adverse Events v3.0) grade ≥3 were 14%. With minimum 5-year follow-up after salvage BT, secondary clinical outcomes including disease-free survival (DFS; includes death from any cause), disease-specific survival, and overall survival (OS) were estimated using the Kaplan-Meier method and modelled using Cox proportional hazards regression. Local tumor progression (ie, LF), distant failure (DF), and biochemical failure (BF) were estimated using cumulative incidence. Time to LF, DF, and BF were modeled by cause-specific Cox proportional hazards regression.RESULTS:
From May 2007 to January 2014, 20 centers registered 100 patients (92 analyzable). Median follow-up is 6.7 years (range, 0.3-11.2); median age 70 years (range, 55-82); median prior EBRT dose 74 Gy [interquartile range (IQR)70 - 76] at a median of 85 months prior (IQR 60-119 months). Androgen deprivation was combined with salvage BT in 16%. Ten-year OS is 70% [95% confidence interval (CI) 58% - 83%]. Nineteen patients died (5 PCa, 10 other, 4 unknown). Ten-year failure rates are local 5% (95% CI, 1-11), distant 19% (95% CI, 10-29), and biochemical 46% (95% CI, 34-57). DFS is 61% at 5 years and 33% at 10 years. No baseline characteristic was significantly associated with any clinical outcome.CONCLUSIONS:
This is the first prospective multicenter trial reporting outcomes of salvage LDR BT for LF after EBRT. Five-year freedom from BF is 68%, comparable to other salvage modalities. Although further LF is rare (5%), BF climbs to 46% by 10 years.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias de la Próstata
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Braquiterapia
Tipo de estudio:
Observational_studies
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Prognostic_studies
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Risk_factors_studies
Límite:
Aged
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Aged80
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Int J Radiat Oncol Biol Phys
Año:
2022
Tipo del documento:
Article