Faculty Collaboration Database

Validation of a 22-Gene Genomic Classifier in Patients With Recurrent Prostate Cancer: An Ancillary Study of the NRG/RTOG 9601 Randomized Clinical Trial. JAMA Oncol 2021 Apr 01;7(4):544-552

Date

02/12/2021

Pubmed ID

33570548

Pubmed Central ID

PMC7879385

DOI

10.1001/jamaoncol.2020.7671

Scopus ID

2-s2.0-85100750925 (requires institutional sign-in at Scopus site)   77 Citations

Abstract

IMPORTANCE: Decipher (Decipher Biosciences Inc) is a genomic classifier (GC) developed to estimate the risk of distant metastasis (DM) after radical prostatectomy (RP) in patients with prostate cancer.

OBJECTIVE: To validate the GC in the context of a randomized phase 3 trial.

DESIGN, SETTING, AND PARTICIPANTS: This ancillary study used RP specimens from the phase 3 placebo-controlled NRG/RTOG 9601 randomized clinical trial conducted from March 1998 to March 2003. The specimens were centrally reviewed, and RNA was extracted from the highest-grade tumor available in 2019 with a median follow-up of 13 years. Clinical-grade whole transcriptomes from samples passing quality control were assigned GC scores (scale, 0-1). A National Clinical Trials Network-approved prespecified statistical plan included the primary objective of validating the independent prognostic ability of GC for DM, with secondary end points of prostate cancer-specific mortality (PCSM) and overall survival (OS). Data were analyzed from September 2019 to December 2019.

INTERVENTION: Salvage radiotherapy (sRT) with or without 2 years of bicalutamide.

MAIN OUTCOMES AND MEASURES: The preplanned primary end point of this study was the independent association of the GC with the development of DM.

RESULTS: In this ancillary study of specimens from a phase 3 randomized clinical trial, GC scores were generated from 486 of 760 randomized patients with a median follow-up of 13 years; samples from a total of 352 men (median [interquartile range] age, 64.5 (60-70) years; 314 White [89.2%] participants) passed microarray quality control and comprised the final cohort for analysis. On multivariable analysis, the GC (continuous variable, per 0.1 unit) was independently associated with DM (hazard ratio [HR], 1.17; 95% CI, 1.05-1.32; P = .006), PCSM (HR, 1.39; 95% CI, 1.20-1.63; P < .001), and OS (HR, 1.17; 95% CI, 1.06-1.29; P = .002) after adjusting for age, race/ethnicity, Gleason score, T stage, margin status, entry prostate-specific antigen, and treatment arm. Although the original planned analysis was not powered to detect a treatment effect interaction by GC score, the estimated absolute effect of bicalutamide on 12-year OS was less when comparing patients with lower vs higher GC scores (2.4% vs 8.9%), which was further demonstrated in men receiving early sRT at a prostate-specific antigen level lower than 0.7 ng/mL (-7.8% vs 4.6%).

CONCLUSIONS AND RELEVANCE: This ancillary validation study of the Decipher GC in a randomized trial cohort demonstrated association of the GC with DM, PCSM, and OS independent of standard clinicopathologic variables. These results suggest that not all men with biochemically recurrent prostate cancer after surgery benefit equally from the addition of hormone therapy to sRT.

TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00002874.

Author List

Feng FY, Huang HC, Spratt DE, Zhao SG, Sandler HM, Simko JP, Davicioni E, Nguyen PL, Pollack A, Efstathiou JA, Dicker AP, Todorovic T, Margrave J, Liu YS, Dabbas B, Thompson DJS, Das R, Dignam JJ, Sweeney C, Attard G, Bahary JP, Lukka HR, Hall WA, Pisansky TM, Shah AB, Pugh SL, Shipley WU, Tran PT

Author

William Adrian Hall MD Professor in the Radiation Oncology department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Aged
Anilides
Follow-Up Studies
Genomics
Humans
Male
Middle Aged
Neoplasm Grading
Neoplasm Metastasis
Neoplasm Recurrence, Local
Nitriles
Prostate-Specific Antigen
Prostatectomy
Prostatic Neoplasms
Tosyl Compounds