Predictive score helps discriminate higher-risk from lower-risk patients in a screening population but still has limitations
PREDICTIVE factors using various models have been employed to identify patients with varying risks for colorectal cancer (CRC). The aim is to target colonoscopy for higher-risk groups and to recommend safer, less-costly modalities for lower-risk groups. Unfortunately, these models fail to achieve sufficient discrimination to be useful in clinical practice.
In this study, Kaminski MF et designed a predictive score for finding out the risk for advanced neoplasia at screening colonoscopy. (Gut 2014 July)
The study involved 35,918 participants (age range, 40 to 66 years; race, white) with advanced neoplasia (cancer or advanced adenomas). The data were taken from a nationwide screening program in Poland. Traditional serrated adenomas, sessile serrated polyps or adenomas, and mixed serrated polyps were considered advanced if they were = 10 mm in diameter.
Using results of multivariate analysis, the researchers assigned risk scores to each category of independent risk factor, as follows:
Age: 40–49 years=0, 50–54 years=1, 55–59 years=2, 60–66 years=3
Family history of CRC: none=0, one first-degree relative aged = 60 years with CRC=1, one first-degree rela tive aged <60 years with CRC or two first-degree relatives with CRC=2
Gender: female=0, male=2
Smoking history: <10 pack-years=0, =10 pack-years=1
Body-mass index: <30 kg/m2=0, =30 kg/m2=1
According to the authors, the risks for advanced neoplasia associated with each score were: 1.32 percent (risk score, 0), 4.21 percent (1), 4.57 percent (2), 6.14 percent (3), 7.74 percent (4), 11.27 percent (5), 13.66 percent (6), and 19.12 percent (7 or 8).
Commenting on the study, Douglas Rex, MD, said that these scores could be useful in helping patients decide what form of screening to utilize, but as was shown in previous studies, their discrimination value is insufficient for use in clinical pratice. “However, these authors join others who suggest that a risk score based on these factors that exceeds a certain level or a positive fecal immunochemical test could be used to identify patients who should undergo screening colonoscopy,” said Dr. Rex.
VitalSigns Issue 65 Vol. 3, July 1-31, 2014