Retrospective Review of Outcomes With Active Surveillance and Active Treatment for Early-Stage Prostate Cancer in a Contemporary Series

Poster Viewing Session E217

Volume 93  Number 3S  Supplement 2015 Author Disclosure: S. Aluwini: None. E. Liem: None. J. Boormans: None. I. Antonisse: None. J.O. Praag: None. W. Kirkels: None. I. Kolkman-Deurloo: None.

2543 The Equivalence of Stereotactic Body Radiation Therapy and Intensity Modulated Radiation Therapy for Prostate Cancer Stratified by 2015 NCCN Risk Groups G. Manahan,1 A. Ricco,2 M. Bernetich,3 R.M. Lanciano,1,4 J. Yang,1,4 A. Hanlon,5 S.A. Arrigo,4 J.P. Lamond,1,4 and L.W. Brady, Jr1,4; 1Drexel University College of Medicine, Philadelphia, PA, 2Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, PA, 3 Rowan University School of Osteopathic Medicine, Stratford, NJ, 4 Delaware County Memorial Hospital/Philadelphia CyberKnife, Drexel Hill, PA, 5University of Pennsylvania, Philadelphia, PA Purpose/Objective(s): Stereotactic body radiation therapy (SBRT) is accepted as an alternative radiation modality for treatment of organconfined prostate cancer; however, no direct comparison to intensity modulated radiation therapy (IMRT) has been published. The goal of this study is to compare biochemical freedom from failure rates (FFBF) between SBRT and IMRT treated in a single hospital system over the same time period stratified by the 2015 National Comprehensive Cancer Network (NCCN) guidelines. Materials/Methods: We retrospectively compared FFBF between SBRT and IMRT for all men treated for organ-confined prostate cancer at our hospital radiation department between January 2007 and December 2012. Prognostic factors assessed included 2015 NCCN risk group, race, age, clinical T stage, initial prostate-specific antigen (PSA), Gleason score, and use of androgen deprivation. Kaplan Meier methodology was used to estimate FFBF, with statistical comparisons accomplished using log-rank tests. Multivariable Cox proportional hazards modeling was used to establish independent factors prognostic of biochemical failures. Results: Two hundred seventy men were treated for organ-confined prostate cancer with either IMRT (nZ120) or SBRT (nZ150). Age at diagnosis was older for the IMRT group with a median of 72 years compared with the SBRT group with a median of 67 years. Significant prognostic factors in univariate analysis for FFBF included NCCN risk groups (PZ.0008), Gleason score (PZ.02), and initial PSA (PZ.007). There was no significant difference in FFBF between IMRT and SBRT (PZ.5). Multivariate analysis revealed only the NCCN risk stratification to be a significant predictor for FFBF (PZ.0035). Five-year actuarial FFBF by NCCN risk stratification was 100% very low risk, 95.8% low risk, 94.1% intermediate risk, 89.9% high risk, and 68.2% very high risk. Sixyear actuarial FFBF by treatment was 91.6% for SBRT versus 89.0% for IMRT. Conclusion: Our data validate the 2015 NCCN stratification guidelines as a predictor for FFBF and confirmed the equivalence of SBRT versus IMRT for treatment of localized prostate cancer. Longer follow-up is planned to confirm the durability of these results. Author Disclosure: G. Manahan: None. A. Ricco: None. M. Bernetich: None. R.M. Lanciano: Independent Contractor; Philadelphia CyberKnife. consultant, lecturer, travel expenses; Philadelphia CyberKnife. Stock; Philadelphia CyberKnife. Supervises two separate radiation oncology sites; Delaware County Memorial Hospital. J. Yang: Stock; Philadelphia CyberKnife. A. Hanlon: Independent Contractor; University of Maryland, Philadelphia CyberKnife, Mainline Health. S.A. Arrigo: Independent Contractor; Philadelphia CyberKnife. Stock; Philadelphia CyberKnife. J. Lamond: Independent Contractor; Philadelphia CyberKnife. travel expenses, lecturer; Philadelphia CyberKnife. Stock; Philadelphia CyberKnife. Supervisor of radiation oncology department; Philadelphia CyberKnife. L.W. Brady: Stock; Philadelphia CyberKnife. Senior supervisor of department; Philadelphia CyberKnife.

2544 Retrospective Review of Outcomes With Active Surveillance and Active Treatment for Early-Stage Prostate Cancer in a Contemporary Series C. Nicholson,1 J. Sathya,1 A. Kamran,2 J. Thoms,1 and V. Gadag1; 1 Memorial University of Newfoundland, St. John’s, NF, Canada, 2Eastern Health Cancer Care Program, St. John’s, NL, Canada Purpose/Objective(s): The harms associated with radical treatment of prostate cancer are well documented in the literature. Both radical prostatectomy and radiation therapy, when compared to active surveillance, are associated with an increased risk of urinary incontinence and erectile dysfunction. Radical prostatectomy carries a low risk of perioperative mortality and rectal or urethral injury. Radiation therapy is associated with increased chronic rectal symptoms. Active surveillance (AS) remains an underutilized option in men with low- or favorable intermediate-risk prostate cancer. We present retrospective data from our center supportive of AS. Materials/Methods: From January 2004 to December 2010, we identified 492 patients with low- or intermediate-risk prostate cancer who were seen at our Cancer Center. Forty-five patients were excluded due to high-risk features; the remaining 447 patients had outcomes data collected retrospectively. One hundred thirty-two patients were followed as per AS protocol within our center with regular clinical followup, serial prostate-specific antigen (PSA), and repeat prostate biopsy within 12 months of initial biopsy and repeated every 2 to 3 years (66 patients had repeat biopsies within this time frame). Three hundred fifteen patients received active treatment (AT) of their choice based on physician recommendation and/or patient preference (174 external beam radiation therapy, 35 brachytherapy, 93 radical prostatectomy, and 13 hormone therapy). The median follow-up was 6 years and 8 months, with follow-up ranging from 4 to 10 years. Average PSA for the AS group was 6.10; for the AT group, it was 7.37. Eighty-two percent of patients in the AS group and 69% in the AT group were T1, and 98% of patients in the AS group and 95% of patients in the AT group had a Gleason score of 6. Patients on AS were treated with the active treatment of their choice in the event of biochemical progression, grade or volume progression on repeat biopsy, or patient preference to go on active therapy. Results: Sixty-four percent (85 of 132 patients) of patients continue to be on AS. The overall survival at the present time is 88.6% for the AS group versus 90.8% for the AT group. There were 44 deaths between the 2 groups; however, only 2 deaths were due to prostate cancer, and both occurred in the AT group. In the AS group no patient had developed local symptomatic disease or metastatic disease. Conclusion: Active surveillance is a valid treatment option, with overall survival comparable to active treatment options and should be considered for every patient presenting with low- or favorable intermediate-risk prostate cancer. Author Disclosure: C. Nicholson: None. J. Sathya: None. A. Kamran: None. J. Thoms: None. V. Gadag: None.

2545 A Biomarker Panel Associated With Distant Metastasis (DM) in Prostate Cancer Patients Treated With Radiation Therapy Is Also Prognostic for DM in a Large Cohort of Prostatectomy Patients A. Pollack,1 N. Erho,2 R. Noronha,2 L. Lam,2 C. Buerki,2 S. Abraham,1 E.A. Klein,3 J.R. Karnes,4 R.B. Den,5 A.P. Dicker,5 A.S. Ishkanian,1 E. Davicioni,2 F.Y. Feng,6 and R. Stoyanova1; 1University of Miami, Miami, FL, 2GenomeDx Biosciences, Vancouver, BC, Canada, 3Cleveland Clinic, Cleveland, OH, 4Mayo Clinic, Rochester, MN, 5Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, PA, 6 University of Michigan, Ann Arbor, MI