TY - JOUR
T1 - Interval to Biochemical Failure Highly Prognostic for Distant Metastasis and Prostate Cancer-Specific Mortality After Radiotherapy
AU - Buyyounouski, Mark K.
AU - Hanlon, Alexandra L.
AU - Horwitz, Eric M.
AU - Pollack, Alan
N1 - Funding Information:
This publication was supported in part by Grants CA-006927 and CA101984-01 from the National Cancer Institute, and a grant from Varian Medical Systems. The contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Cancer Institute. The authors thank Dr. Gerald Hanks for his leadership in the establishment of the Fox Chase Cancer Center database for the treatment of prostate cancer reported herein and Ruth Peter for her dedication to its maintenance.
PY - 2008/1/1
Y1 - 2008/1/1
N2 - Purpose: Few biochemical parameters have been related to mortality. The present study examined the clinical utility of the interval to biochemical failure (IBF) as a prognostic factor for distant metastasis (DM) and prostate cancer-specific mortality (PCSM) after radiotherapy. Methods and Materials: The study group consisted of 211 T1c-T3Nx-N0M0 patients who had experienced BF among 1,174 men treated with three-dimensional conformal radiotherapy alone. Biochemical failure was defined as a post-treatment prostate-specific antigen (PSA) level of at, or greater than, the PSA nadir plus 2 ng/mL. Cox proportional hazards modeling was used to identify independent predictors of DM and PCSM on multivariate analysis. Results: An IBF of <18 months was independently predictive for DM (p = 0.008), as was a Gleason score of 7-10 (p = 0.0005), PSA nadir ≥2 ng/mL (p = 0.04), and decreasing radiation dose (p = 0.02) on multivariate analysis, including increasing pretreatment PSA level, PSA nadir ≥2.5 ng/mL, PSA doubling time of <3 months, and Stage T3 disease. An IBF of <18 months was the only predictor of PCSM (p = 0.0003) in the same model. The actuarial 5-year DM rate for an IBF of <18 vs. ≥18 months was 52% vs. 20% (p < 0.0001), and the actuarial PCSM rate was 36% vs. 6%, respectively (p = 0.0001). Conclusions: The IBF is an important descriptor of the PSA kinetics after radiotherapy to identify men at high risk of clinical failure and death. A IBF of <18 months could aid in selecting men for early, aggressive salvage therapy or participation in a clinical trial.
AB - Purpose: Few biochemical parameters have been related to mortality. The present study examined the clinical utility of the interval to biochemical failure (IBF) as a prognostic factor for distant metastasis (DM) and prostate cancer-specific mortality (PCSM) after radiotherapy. Methods and Materials: The study group consisted of 211 T1c-T3Nx-N0M0 patients who had experienced BF among 1,174 men treated with three-dimensional conformal radiotherapy alone. Biochemical failure was defined as a post-treatment prostate-specific antigen (PSA) level of at, or greater than, the PSA nadir plus 2 ng/mL. Cox proportional hazards modeling was used to identify independent predictors of DM and PCSM on multivariate analysis. Results: An IBF of <18 months was independently predictive for DM (p = 0.008), as was a Gleason score of 7-10 (p = 0.0005), PSA nadir ≥2 ng/mL (p = 0.04), and decreasing radiation dose (p = 0.02) on multivariate analysis, including increasing pretreatment PSA level, PSA nadir ≥2.5 ng/mL, PSA doubling time of <3 months, and Stage T3 disease. An IBF of <18 months was the only predictor of PCSM (p = 0.0003) in the same model. The actuarial 5-year DM rate for an IBF of <18 vs. ≥18 months was 52% vs. 20% (p < 0.0001), and the actuarial PCSM rate was 36% vs. 6%, respectively (p = 0.0001). Conclusions: The IBF is an important descriptor of the PSA kinetics after radiotherapy to identify men at high risk of clinical failure and death. A IBF of <18 months could aid in selecting men for early, aggressive salvage therapy or participation in a clinical trial.
KW - Prognostic factor
KW - Prostate cancer
KW - Prostate-specific antigen
KW - Radiotherapy
KW - Treatment failure
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U2 - 10.1016/j.ijrobp.2007.05.047
DO - 10.1016/j.ijrobp.2007.05.047
M3 - Article
C2 - 17919840
AN - SCOPUS:37049031020
VL - 70
SP - 59
EP - 66
JO - International Journal of Radiation Oncology Biology Physics
JF - International Journal of Radiation Oncology Biology Physics
SN - 0360-3016
IS - 1
ER -