Importance of Local Control in Early-Stage Prostate Cancer: Outcomes of Patients With Positive Post-Radiation Therapy Biopsy Results Treated in RTOG 9408
- NRG Statistics and Data Management Center, Philadelphia, Pennsylvania (United States)
- Centre Hospitalier de l'Université de Montréal-Notre Dame, Montreal, Quebec (Canada)
- McGill University, Montreal, Quebec (Canada)
- Medical College of Wisconsin, Milwaukee, Wisconsin (United States)
- Cross Cancer Institute, Edmonton, Alberta (Canada)
- Sutter General Hospital, Sacramento, California (United States)
- Michigan Cancer Research Consortium CCOP (United States)
- H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida (United States)
- Washington University, St. Louis, Missouri (United States)
- Albert Einstein Medical Center, Bronx, New York, New York (United States)
- Christiana Care Health Services Inc CCOP, Newark, Delaware (United States)
- Cedars-Sinai Medical Center, Los Angeles, California (United States)
- Dana-Farber Cancer Institute, Boston, Massachusetts (United States)
Purpose: The purpose of this study was to assess the association between positive post-radiation therapy (RT) biopsy results and subsequent clinical outcomes in males with localized prostate cancer. Methods and Materials: Radiation Therapy Oncology Group study 94-08 analyzed 1979 males with prostate cancer, stage T1b-T2b and prostate-specific antigen concentrations of ≤20 ng/dL, to investigate whether 4 months of total androgen suppression (TAS) added to RT improved survival compared to RT alone. Patients randomized to receive TAS received flutamide with luteinizing hormone releasing hormone (LHRH) agonist. According to protocol, patients without evidence of clinical recurrence or initiation of additional endocrine therapy underwent repeat prostate biopsy 2 years after RT completion. Statistical analysis was performed to evaluate the impact of positive post-RT biopsy results on clinical outcomes. Results: A total of 831 patients underwent post-RT biopsy, 398 were treated with RT alone and 433 with RT plus TAS. Patients with positive post-RT biopsy results had higher rates of biochemical failure (hazard ratio [HR] = 1.7; 95% confidence interval [CI] = 1.3-2.1) and distant metastasis (HR = 2.4; 95% CI = 1.3-4.4) and inferior disease-specific survival (HR = 3.8; 95% CI = 1.9-7.5). Positive biopsy results remained predictive of such outcomes after correction for potential confounders such as Gleason score, tumor stage, and TAS administration. Prior TAS therapy did not prevent elevated risk of adverse outcome in the setting of post-RT positive biopsy results. Patients with Gleason score ≥7 with a positive biopsy result additionally had inferior overall survival compared to those with a negative biopsy result (HR = 1.56; 95% CI = 1.04-2.35). Conclusions: Positive post-RT biopsy is associated with increased rates of distant metastases and inferior disease-specific survival in patients treated with definitive RT and was associated with inferior overall survival in patients with high-grade tumors.
- OSTI ID:
- 22462382
- Journal Information:
- International Journal of Radiation Oncology, Biology and Physics, Vol. 92, Issue 4; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0360-3016
- Country of Publication:
- United States
- Language:
- English
Similar Records
Impact of Ultrahigh Baseline PSA Levels on Biochemical and Clinical Outcomes in Two Radiation Therapy Oncology Group Prostate Clinical Trials
Percentage of Positive Biopsy Cores: A Better Risk Stratification Model for Prostate Cancer?