Novel Clinical Prognostic Stage Group System for Prostate Cancer
Posted: Wednesday, February 17, 2021
The international staging collaboration for prostate cancer (STAR-CAP) proposes a new pretreatment, predictive staging system for nonmetastatic prostate cancer. This staging classification system is based on competing-risk regression statistical modeling. It may be used to predict the risk of prostate cancer–specific mortality for a diverse cohort of men diagnosed with clinically localized prostate cancer. This cohort study was published by Robert T. Dess, MD, of the University of Michigan School of Medicine, Ann Arbor, and colleagues in JAMA Oncology.
“Localized prostate cancer is sometimes less aggressive, sometimes more, and whether we’re patients, physicians or researchers, we all want to know as best we can how aggressive a particular cancer is likely to be,” stated Dr. Dess in an institutional press release. “That information helps with our conversations with patients, [and] it helps with clinical trial design….”
Tumor and outcome data were examined from a cohort of 19,684 patients treated with standard curative treatment. Key variables included patients’ age, tumor category, Gleason grade of cell abnormality, pretreatment prostate-specific antigen (PSA) levels, and percentage of positive core biopsy results among biopsies performed. They were given a point value (between 0–8) to assign patients to a particular stage. This new staging model, referred to as the Score system, is similar to other nonvalidated models.
The median follow-up was 71.8 months, and 4,078 men were following for at least 10 years. The predicted 10-year prostate cancer–specific mortality for the nine Score groups ranged from 0.3% to 40% in the validation set. According to the authors, the 10-year C index (model discrimination) of 0.796 exceeded that of the American Joint Committee on Cancer (AJCC) 8th edition (0.757). According to the study authors, the novel staging system also appeared to outperform the National Comprehensive Cancer Network (NCCN) and Cancer of the Prostate Risk Assessment (CAPRA) risk grouping three- and four-tier classification systems.
Disclosure: The study authors reported no conflicts of interest.