Abstract B59: Predictors of early versus late biochemical recurrence after open radical prostatectomy in a patient cohort with T2/T3N0M0 prostate cancer treated within the PSA-era

Abstract

Abstract Introduction: Patients treated with radical prostatectomy (RP) differ in their risk of prostate cancer (PCa) recurrence. By determining factors associated with an increased risk of biochemical (PSA) recurrence (BCR), patients can be provided with personalized care to prevent disease progression. Identifying which patients are at risk of earlier versus later BCR after surgery is of interest in order to guide monitoring of disease progression and treatment options. Objectives: We evaluated variables associated with PCa progression among a patient population treated with RP. In particular, we examined factors associated with earlier BCR (≤5 years post-RP) versus later BCR (>5 years post-RP) taking into account potential differences across racial/ethnic groups present in this population. Methods: An IRB approved database was used to obtain data on a patient population at USC/Norris Comprehensive Cancer Center with pathologically confirmed localized PCa (T2/T3) without lymph node involvement who underwent RP in the PSA era (1988-2009). We analyzed data on 2,485 patients after excluding individuals treated with neo-adjuvant hormonal therapy. Kaplan Meier and Cox regression analyses were used to evaluate biochemical recurrence-free survival (BCRFS) and risk of BCR adjusting for clinical variables. Results: Among the 2,485 patients, 268 (11%) experienced BCR. Of these individuals, 212 (79%) had BCR ≤5 years after RP versus 56 (21%) >5 years after surgery. The median (range) of follow-up time among patients without any recurrence is 7.45 (2.0-20.4) years and among patients with BCR is 2.9(0.17-15.12) years. The racial distribution is 2,163 (87%) Non-Hispanic White (NHW), 126 (5%) Hispanic, 95 (4%) African-American, and 78 (3%) Asian/Pacific Islander, with 23 patients excluded due to unknown race. Compared to other racial/ethnic groups, more African-American men were diagnosed when younger than 65 years old (66%) (p<0.001). Similarly, 75% of African-Americans who experienced BCR were less than age 65. The 5 and 10 year BCRFS for this cohort are 91% and 88% respectively. For patients who remained BCR-free at 5 years after RP, their BCRFS at 10 years was 97%. The strongest BCR predictors for individuals who had recurrence within 5 years or less post-RP were T3 pathological stage (extracapsular extension or seminal vesicle invasion), positive surgical margins, and Gleason score 7-10. Among those who experienced BCR after 5 years post-RP, the strongest predictors included total PSA values >10-20 ng/ml, Gleason score 8-10, 61-65 years of age at diagnosis, and extracapsular extension. Radiation therapy and race/ethnicity were not significantly associated with BCR in the multivariate Cox regression for either BCR group. Conclusions: Certain clinical characteristics of localized prostate cancer patients may be useful in determining who is at risk of earlier or later BCR following RP. These data can improve prognosis by providing guidance in determining the appropriate length of time to monitor disease progression and possible treatment options for patients. Citation Format: Ahva Shahabi, Inderbir S. Gill, Gary Lieskovsky, Eila C. Skinner, Siamak Daneshmand, Jacek Pinski, Mariana C. Stern. Predictors of early versus late biochemical recurrence after open radical prostatectomy in a patient cohort with T2/T3N0M0 prostate cancer treated within the PSA-era [abstract]. In: Proceedings of the AACR Special Conference on Advances in Prostate Cancer Research; 2012 Feb 6-9; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2012;72(4 Suppl):Abstract nr B59.