Oncological Outcomes After Radical Prostatectomy for High-Risk Prostate Cancer Based on New Gleason Grouping System: A Validation Study From University of Southern California With 3,755 Cases

To assess the prognostic value of new Gleason grade grouping system in high-risk prostate cancer patients, we compared oncological outcomes after radical prostatectomy for patients with Gleason score 8 versus 9-10.

Between 1987 and 2008, 3,755 men underwent radical prostatectomy with curative intent at University of Southern California. Patients who had Gleason score 8-10 at final histopathological evaluation (pT2-4N0) were included in this study. Eligible patients were divided into two groups; 226 with Gleason score 8 and 132 with Gleason score 9-10. Various patient and disease characteristics as well as oncological outcomes (biochemical recurrence, clinical recurrence, and overall survival) were compared between the groups. Impact of Gleason score on outcomes was controlled for preoperative prostate specific antigen, pathological stage, use of adjuvant radiotherapy, and neoadjuvant/adjuvant hormone therapy in multivariable analyses.

A total of 358 patients (mean age: 65 years) were included in the analysis. Mean age and median duration of follow-up (9.6 years) were comparable between the study groups. Gleason 9-10 prostate cancer was associated with worse biochemical (HR 1.6; 95%CI [1.1-2.3]) and clinical recurrence free survival (HR = 1.9; 95%CI [1.1-3.3]); however, overall survival did not differ significantly between the groups. In addition, more patients with Gleason score 9-10 received adjuvant hormone therapy in the course of disease.

Long-term follow-up after radical prostatectomy revealed significant differences in disease-specific outcomes between patients with Gleason score 8 versus 9-10. This sub-classification of high-risk patients might be helpful for patient counseling and determining therapeutic strategies. Prostate 9999: XX-XX, 2017. © 2017 Wiley Periodicals, Inc.

The Prostate. 2017 Feb 01 [Epub ahead of print]

Hooman Djaladat, Erfan Amini, Weichen Xu, Jie Cai, Siamak Daneshmand, Gary Lieskovsky

The Institute of Urology, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California., Department of Urology, Uro-Oncology Research Center, Tehran University of Medical Sciences, Tehran, Iran.