This clinical utility study is based on a review of real but de-identified and randomized patient cases and aims to evaluate radiation oncologist's treatment recommendations before and after reviewing the results provided by the Decipher test. The primary intent is to help guide development and design of future clinical utility studies for Decipher.

Patient cases were selected using existing data generated from patient specimens collected in a separate IRB approved protocol, in which pathological specimens were tested to generate a test result for comparison to outcomes. Those test results are presented in this study, but not the individual patient outcomes. Physicians participating in this current study did not provide care for any of the subjects in the previous study. Cases are presented to physicians in a randomized order and in a form that prevents the patients from being identified, directly or indirectly.

High risk patient cases were selected to reflect a range of clinicopathological variables and were further stratified based on the Decipher predicted probability of developing metastasis 5 years after RP and 3 years after BCR (as shown in the table below). High (low) Decipher (GC) risk was defined as a 5- or 3-year predicted probability of metastasis greater (less) than 6% for the adjuvant setting and greater (less) than 18% for the salvage setting.

Case Inclusion Criteria:

Patient cases eligible for this study were treated with radical prostatectomy and have one or more adverse pathological features present defined as:

Pathological Gleason score ≥ 8 or Gleason score 7 with primary pattern 4; Pathological stage T3a (= Extracapsular extension) or T3b (=Seminal vesicle invasion); Positive surgical margins Gleason grade upgrade from biopsy to surgery Detectable PSA, defined as failure of PSA to fall to undetectable, or PSA detectable and rising on 2 or more subsequent determinations

Case Exclusion Criteria:

Metastatic disease (M+) prior to surgery Received any neo-adjuvant prostate cancer treatment prior to radical prostatectomy (radiation, hormone, chemotherapy)

Physicians:

Radiation oncologists targeted for recruitment into the study must meet the following criteria:

• Practicing, board-certified radiation oncologists.
• Perform consultations on at least 80 patients with prostate cancer annually.

Patients:

Patients diagnosed with localized prostate cancer that received radical prostatectomy as the first line treatment.

De-identified patient cases were selected from an independent clinical validation study of patients with adverse pathology features treated between 2000 and 2006. (Karnes et al., 2013)