Radical Prostatectomy In Clinically Localized Prostate Cancer-The Risk Of Extraprostatic Spread By Nccn Risk Group And Its Implications For Adjuvant Therapy: An Analysis Of 23,988 Patients

5125 Background: Swanson et al recently reported an update of SWOG 8794 (ASTRO 2008, oral presentation) revealing a 10% absolute overall survival benefit at 15 years with adjuvant radiation therapy for patients with extraprostatic extension (EPE) or positive margins after radical prostatectomy (RP). In this population based analysis, we analyze and report on the pathologic rates of EPE or positive margins in clinically localized prostate cancer as well as how often these patients have received adjuvant radiation therapy. Methods: The Surveillance, Epidemiology and End Results (SEER) registry was used to identify patients between 2004–2005 with clinically staged T1-T2c prostate cancer who underwent RP. Patients were stratified using NCCN risk groups into low (T1c- T2a, PSA less than 10ng/ml, Gleason 2–6), intermediate (T2b, PSA 10–20ng/ml, Gleason 7), and high (T2c, PSA greater than 20ng/ml, Gleason 8–10). Results: 23,988 patients were identified: 6,314 in the NCCN low risk group (LR), 12,052 in the NCCN intermediate risk group (IR), and 5,622 in the NCCN high risk group (HR). Overall, 68.2% of patients had organ-confined disease with negative margins. However, the risk of EPE or positive margins increased with the NCCN risk group, PSA value, and Gleason score (see table ). Of those who met criteria for adjuvant radiation, 11.9% received the treatment: 4.7% of the LR group, 9.2% of the IR group and 18.9% of the HR group. Conclusions: This is, to our knowledge, the largest reported multi-institutional surgical series of clinically localized prostate cancer. Patients can use this data to be counseled on their risk of requiring adjuvant radiation based on their pre-treatment parameters. This data also reveals that nearly one third of all patients met the indications for adjuvant radiation, but only a small percentage of them received this treatment. [Table: see text] No significant financial relationships to disclose.