Dose Escalation for Prostate Cancer Radiotherapy: Predictors of Long-Term Biochemical Tumor Control and Distant Metastases–Free Survival Outcomes

• Published in: European urology 2011-12, Vol.60 (6), p.1133-1139
• Main Authors: Zelefsky, Michael J, Pei, Xin, Chou, Joanne F, Schechter, Michael, Kollmeier, Marisa, Cox, Brett, Yamada, Yoshiya, Fidaleo, Anthony, Sperling, Dahlia, Happersett, Laura, Zhang, Zhigang
• Format: Article
• Language: English
• Subjects: Aged; Androgen Antagonists - therapeutic use; Androgen deprivation therapy; Antineoplastic Agents, Hormonal - therapeutic use; Biological and medical sciences; Chemotherapy, Adjuvant; Disease-Free Survival; Dose escalation; External beam radiotherapy; Gynecology. Andrology. Obstetrics; Humans; Kaplan-Meier Estimate; Male; Male genital diseases; Medical sciences; Middle Aged; Neoadjuvant Therapy; Neoplasm Staging; Nephrology. Urinary tract diseases; New York City; Nomograms; Proportional Hazards Models; Prostate cancer; Prostate-Specific Antigen - blood; Prostatic Neoplasms - immunology; Prostatic Neoplasms - mortality; Prostatic Neoplasms - radiotherapy; Prostatic Neoplasms - secondary; PSA relapse–free survival; Radiotherapy Dosage; Radiotherapy, Conformal - adverse effects; Radiotherapy, Conformal - mortality; Radiotherapy, Intensity-Modulated - adverse effects; Radiotherapy, Intensity-Modulated - mortality; Retrospective Studies; Risk Assessment; Risk Factors; Time Factors; Treatment Outcome; Tumors; Tumors of the urinary system; Urinary tract. Prostate gland; Urology
• ISSN: 0302-2838; 1873-7560
• DOI: 10.1016/j.eururo.2011.08.029

Abstract Background Higher radiation dose levels have been shown to be associated with improved tumor-control outcomes in localized prostate cancer (PCa) patients. Objective Identify predictors of biochemical tumor control and distant metastases–free survival (DMFS) outcomes for patients with clinically localized PCa treated with conformal external-beam radiotherapy (RT) as well as present an updated nomogram predicting long-term biochemical tumor control after RT. Design, setting, and participants This retrospective analysis comprised 2551 patients with clinical stages T1–T3 PCa. Median follow-up was 8 yr, extending >20 yr. Intervention Prescription doses ranged from 64.8 to 86.4 Gy. A total of 1249 patients (49%) were treated with neoadjuvant and concurrent androgen-deprivation therapy (ADT); median duration of ADT was 6 mo. Measurements A proportional hazards regression model predicting the probability of biochemical relapse and distant metastases after RT included pretreatment prostate-specific antigen (PSA) level, clinical stage, biopsy Gleason sum, ADT use, and radiation dose. A nomogram predicting the probability of biochemical relapse after RT was developed. Results and limitations Radiation dose was one of the important predictors of long-term biochemical tumor control. Dose levels