AUA 2017: Analysis of the predictive utility of Prognostic Grade Groups (PGG) for predicting perioperative oncologic outcomes of radical prostatectomy in the Shared Equal Access Regional Cancer Hospital (SEARCH) database.

Boston, MA (UroToday.com) In 2015, the Gleason Scoring system was reclassified with the introduction of the Prognostic Grade Groups (PGG) 1 through 5. It is a well-established measure predictive of oncologic outcomes in patients who undergo radical prostatectomy (RP). Prostate cancers often have areas with differentiated cancerous tissue. Thus, grades (numbers 1 to 5) are assigned to the two areas that make up most of the cancer. These two grades are added to yield the Gleason score which is the sum assigned to define how much the cancerous tissue in the prostate resembles normal prostate tissue. This study assessed the administration of Prognostic Grade Groups (PGG) in the Shared Equal Access Regional Cancer Hospital (SEARCH) database, a multiracial equal access healthcare system that allowed for captive follow-up, to assess predictive perioperative oncologic outcomes.

A total record of 4,200 men who underwent radical prostatectomy at one of six Veterans Affairs hospitals were reviewed between 1988 and 2015. Logistic regression models were used to assess the predictive utility of biopsy PGG for multiple perioperative clinical endpoints. Additionally, the impact of race on PGG were tested.

The cohort of PGG 1 through 5 was composed of 1,989 (47%), 1,142 (27%), 515 (12%), 402 (10%), 152 (4%), respectively. African Americans (AA) made up 1,569 (38%) of the cohort. Higher stage, older age, higher preoperative PSA and more positive biopsy cores associated with higher biopsy PGG (p≤0.012). Furthermore, higher PGG was associated with postoperative oncologic outcomes such as higher risk of extracapsular extension (ECE), seminal vesicle invasion (SVI), positive surgical margins (PSM), lymph node involvement (LNI), and lower likelihood of achieving PSA levels <0.001 after surgery (all p<0.001). Biopsy to RP concordance was 24-58%.

In conclusion, the 2015 Prostate Grade Groups predicted multiple perioperative, oncologic end-points in a shared access health system. There was relatively less upgrading at higher Grade Groups in AA men suggesting biopsy to RP concordance was significant. Perioperative validity of the 2015 Grade Groups can be further confirmed by longer-term oncologic endpoints.

Presented By: Ariel Schulman

Authors: Ariel Schulman*, Lauren Howard, Kae Jack Tay, Rajan Gupta, Efrat Tsivian, Durham, NC, Christopher Amling, Portland, OR, William Aronson, Los Angeles, CA, Matthew Cooperberg, San Francisco, CA, Christopher Kane, San Diego, CA, Martha Terris, Augusta, GA, S

Written By: Rita Derderian, University of California, Irvine for UroToday.com

at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA