RNA CCP Score Provides Significant Prognostic Information

Rancho Mirage, CA—In a study conducted by Jack M. Cuzick, PhD, and colleagues at the Centre for Cancer Prevention, Wolfson Institute of Preventive Medicine, London, United Kingdom, the researchers found that cell cycle progression (CCP) score can be used to determine which patients with prostate cancer can be safely managed with a conservative policy, thus avoiding radical treatment.

Results of the study were reported by Michael K. Brawer, MD, of Myriad Genetics Laboratories, Inc., during a poster session at the South Central Section of the American Urological Association 93rd Annual Meeting. The poster was titled Validation of an RNA Cell Progression Score for Predicting Prostate Cancer Death in a Conservatively Managed Needle Biopsy Cohort.

Noting that, “Better markers are needed to guide management [of prostate cancer] and avoid unnecessary treatment,” the researchers conducted the retrospective cohort study to validate the predictive value of a CCP score and a prespecified linear combination of the CCP score with standard clinical values (Cancer of the Prostate Risk Assessment [CAPRA] score) to create a combined clinical cell cycle risk (CCR) score that can be used to predict death from prostate cancer. The study cohort was a conservatively managed group of 585 men in the United Kingdom who were diagnosed by needle biopsy from 1990 to 2003.

The researchers utilized data from the UK cancer registry supplemented by hospital records and histopathology review of diagnostic needle biopsies. The study’s primary end point was death from prostate cancer. Clinical variables including centrally reviewed Gleason score, baseline prostate-specific antigen, age, clinical stage, and extent of disease were combined into a single predefined risk assessment (CAPRA) score.

In univariate analysis, for a 1-unit change of the score, the CCP hazard ratio (HR) was 2.08 (95% confidence interval [CI], 1.76-2.46; P<10-13); in a bivariate analysis that included CAPRA, the CCP score HR was “only marginally decreased” (HR=1.76; 95% CI, 1.44-2.14; P<10-6), the researchers said.

The predefined CCR score that combined CCP and CAPRA was highly predictive (HR=2.17; 95% CI, 1.8-2.6, c2=89.0; P<10-20); the CCR score captured all available information regarding prognosis. The predictive value of the CCP score was maintained for 10 years with no significant interaction with other prognostic factors.

Eighty men (13.7%) were identified in the low-risk group and they had a 10 year prostate cancer mortality of 4.3%; 19 (3.2%) of those men were identified at higher risk with CCR. CCR identified an additional 31 men (5.3%) with CAPRA >2, but with a risk of <4.3% using the combined score.

In summary, the researchers said, “The CCP score provides substantially more significant pretreatment prognostic information than available from clinical variables and is useful for determining which patients can be safely managed by a conservative policy avoiding radical treatment.”