title: Evaluation of a genomic classifier in radical prostatectomy patients with lymph node metastasis.
abstract: OBJECTIVE
  To evaluate the performance of the Decipher test in predicting lymph node invasion (LNI) on radical prostatectomy (RP) specimens.
  
  
  METHODS
  We identified 1,987 consecutive patients with RP who received the Decipher test between February and August 2015 (contemporary cohort). In the contemporary cohort, only the Decipher score from RP specimens was available for analysis. In addition, we identified a consecutive cohort of patients treated with RP between 2006 and 2012 at the University of California, San Diego, with LNI upon pathologic examination (retrospective cohort). The retrospective cohort yielded seven, 22, and 18 tissue specimens from prostate biopsy, RP, and lymph nodes (LNs) for individual patients, respectively. Univariable and multivariable logistic regression analyses were used to evaluate the performance of Decipher in the contemporary cohort with LNI as the endpoint. In the retrospective cohort, concordance of risk groups was assessed using validated cut-points for low (<0.45), intermediate (0.45-0.60), and high (>0.60) Decipher scores.
  
  
  RESULTS
  In the contemporary cohort, 51 (2.6%) patients had LNI. Decipher had an odds ratio of 1.73 (95% confidence interval, 1.46-2.05) and 1.42 (95% confidence interval, 1.19-1.7) per 10% increase in score on univariable and multivariable (adjusting for pathologic Gleason score, extraprostatic extension, and seminal vesicle invasion), respectively. No significant difference in the clinical and pathologic characteristics between the LN positive patients of contemporary and retrospective cohorts was observed (all P>0.05). Accordingly, among LN-positive patients in the contemporary cohort and retrospective cohort, 80% and 77% had Decipher high risk scores (P=1). In the retrospective cohort, prostate biopsy cores with the highest Gleason grade and percentage of tumor involvement had 86% Decipher risk concordance with both RP and LN specimens.
  
  
  CONCLUSIONS
  Decipher scores were highly concordant between pre- and post-surgical specimens. Further, Decipher scores from RP tissue were predictive of LNI at RP. If validated in a larger cohort of prostate biopsy specimens for prediction of adverse pathology at RP, Decipher may be useful for improved pre-operative staging.
authors.affiliation: Department of Urology, University of California, San Diego, San Diego, CA, USA.
authors.forename: Hak J
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: GenomeDx Biosciences Inc., Vancouver, BC, Canada.
authors.forename: Kasra
authors.initials: K
authors.lastname: Yousefi
authors.affiliation: GenomeDx Biosciences Inc., Vancouver, BC, Canada.
authors.forename: Zaid
authors.initials: Z
authors.lastname: Haddad
authors.affiliation: Vattikuti Urology Institute, Henry Ford Hospital, Detroit, MI.
authors.forename: Firas
authors.initials: F
authors.lastname: Abdollah
authors.affiliation: GenomeDx Biosciences Inc., Vancouver, BC, Canada.
authors.forename: Lucia Lc
authors.initials: LL
authors.lastname: Lam
authors.affiliation: GenomeDx Biosciences Inc., Vancouver, BC, Canada.
authors.forename: Heesun
authors.initials: H
authors.lastname: Shin
authors.affiliation: GenomeDx Biosciences Inc., Vancouver, BC, Canada.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Alshalalfa
authors.affiliation: Department of Urology, University of California, San Diego, San Diego, CA, USA.
authors.forename: Elana
authors.initials: E
authors.lastname: Godebu
authors.affiliation: UC San Diego Health System, San Diego, CA.
authors.forename: Song
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Pathology, University of California, San Diego, San Diego, CA, USA.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Shabaik
authors.affiliation: GenomeDx Biosciences Inc., Vancouver, BC, Canada.
authors.forename: Elai
authors.initials: E
authors.lastname: Davicioni
authors.affiliation: Department of Urology, University of California, San Diego, San Diego, CA, USA.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Kane
keywords: biopsy; decipher; genomic classifier; lymph node invasion; prognosis; prostate; radical prostatectomy