Author(s): Andrew J. Armstrong, MD, ScM1; Vinnie Y.T. Liu, MSc2; Ramprasaath R. Selvaraju, PhD2; Emmalyn Chen, PhD2; Jeffry P. Simko, MD, PhD3; Sandy DeVries, MA3; Oliver Sartor, MD4; Howard M. Sandler, MD5; Osama Mohamad, MD, PhD3; Huei-Chung Huang, MA2; Jacqueline Griffin, PhD2; Rikiya Yamashita, MD, PhD2; Andre Esteva, PhD2; Phuoc T. Tran, MD, PhD6; Daniel E. Spratt, MD7; John Hi Carson, MD8; Christopher Peters, MD9; Elizabeth Gore, MD10,11; Steve P. Lee, MD, PhD12; Jedidiah M. Monson, MD13; Mark E. Augspurger, MD14; Ali El-Gayed, MD15; Joseph P. Rodgers, MS16,17; Rana McKay, MD18; Todd Morgan, MD19; Felix Y. Feng, MD3; Paul L. Nguyen, MD20;
PURPOSE
Long-term androgen deprivation therapy (ADT) improves survival in men with high-risk localized prostate cancer (PCa) receiving radiotherapy (RT). Predictive biomarkers are needed to guide ADT duration.
METHODS
A multimodal artificial intelligence (MMAI)???derived predictive biomarker was trained for long-term (LT) versus short-term (ST) ADT using pretreatment digital prostate biopsy images and clinical data (age, prostate-specific antigen, Gleason, and T stage) from six NRG Oncology phase III randomized radiotherapy trials. The novel MMAI-derived biomarker was developed to predict the differential benefit of LT-ADT on the primary end point, distant metastasis (DM). MMAI predictive utility was validated on a seventh randomized trial, RTOG 9202 (N = 1,192), which randomly assigned men to RT + ST-ADT (4 months) versus RT + LT-ADT (28 months). Fine-Gray and cumulative incidence analyses for DM, and secondarily, death with DM, were performed. Deaths without DM were treated as competing risks.
RESULTS
In the validation cohort (median follow-up, 17.2 years), LT-ADT significantly improved DM from 26% to 17% (subdistribution hazard ratio [sHR], 0.64 [95% CI, 0.50 to 0.82], P < .001). A significant biomarker-treatment predictive interaction was observed (P = .04) for DM, whereby MMAI biomarker???positive men (n = 785, 66%) had reduced DM with LT-ADT versus ST-ADT (sHR, 0.55 [95% CI, 0.41 to 0.73], P < .001), whereas no treatment benefit was observed for MMAI biomarker???negative men (n = 407; sHR, 1.06 [95% CI, 0.61 to 1.84], P = .84). The estimated 15-year DM risk difference between RT + LT-ADT and RT + ST-ADT was 14% in MMAI biomarker???positive men and 0% in MMAI biomarker???negative men. The MMAI biomarker was also prognostic for DM, irrespective of treatment (sHR, 2.35 [95% CI, 1.72 to 3.19], P < .001).
CONCLUSION
To our knowledge, the MMAI model is the first validated predictive biomarker to guide ADT duration with RT in localized/locally advanced PCa. Approximately one third of men with high-risk PCa could safely be spared the additional 24 months of ADT and the associated morbidity.
Author Affiliations
1Duke University Medical Center, Durham, NC; 2Artera Inc, Los Altos, CA; 3University of California San Francisco, San Francisco, CA; 4Mayo Clinic, Rochester, MN; 5Cedars-Sinai Medical Center, Los Angeles, CA; 6University of Maryland, Baltimore, MD; 7Case Western Reserve University, Cleveland, OH; 8Saint John Regional Hospital, Saint John, New Brunswick, CA; 9Northeast Radiation Oncology Center, Dunmore, PA accrual for Regional Hospital of Scranton; 10Zablocki Veterans Administration Medical Center, Milwaukee, WI; 11Medical College of Wisconsin, Milwaukee, WI, Accrual for Clarkson Hospital; 12Long Beach VA Healthcare System, Long Beach, CA; 13Saint Agnes Medical Center, Fresno, CA; 14Baptist Medical Center South, Jacksonville, FL; 15Saskatoon Cancer Centre, Saskatoon, SK; 16NRG Oncology Statistics and Data Management Center, Philadelphia, PA; 17American College of Radiology, Philadelphia, PA; 18University of California San Diego Moores Cancer Center, La Jolla, CA; 19University of Michigan, Ann Arbor, MI; 20Brigham and Women's Hospital, Boston, MA