Fecal immunochemical test accuracy in average-risk colorectal cancer screening

AIM:To assess the fecal immunochemical test(FIT)accuracy for colorectal cancer(CRC)and advanced neoplasia(AN)detection in CRC screening.METHODS:We performed a multicentric,prospective,double blind study of diagnostic tests on asymptomatic average-risk individuals submitted to screening colonoscopy.Two stool samples were collected and the fecal hemoglobin concentration was determined in the first sample(FIT1)and the highest level of both samples(FITmax)using the OC-sensor.Areas under the curve(AUC)for CRC and AN were calculated.The best FIT1and FITmax cut-off values for CRC were determined.At this threshold,number needed to scope(NNS)to detect a CRC and an AN and the cost per lesion detected were calculated.RESULTS:About 779 individuals were included.An AN was found in 97(12.5%)individuals:a CRC in 5(0.6%)and an advanced adenoma(≥10 mm,villous histology or high grade dysplasia)in 92(11.9%)subjects.For CRC diagnosis,FIT1 AUC was 0.96(95%CI:0.95-0.98)and FITmax AUC was 0.95(95%CI:0.93-0.97).For AN,FIT1 and FITmax AUC were similar(0.72,95%CI:0.66-0.78 vs 0.73,95%CI:0.68-0.79,respectively,P=0.34).Depending on the number of determinations and the positivity threshold cut-off used sensitivity for AN detection ranged between 28%and 42%and specificity between 91%and 97%.At the best cut-off point for CRC detection(115 ng/mL),the NNS to detect a CRC were 10.2 and 15.8;and the cost per CRC was 1814€and 2985€on FIT1 and FITmax strategies respectively.At this threshold the sensitivity,NNS and cost per AN detected were 30%,1.76,and 306€,in FIT1 strategy,and 36%,2.26€and 426€,in FITmax strategy,respectively.CONCLUSION:Performing two tests does not improve diagnostic accuracy,but increases cost and NNS to detect a lesion.

Colorectal cancer prognosis twenty years later

AIM:To evaluate changes in colorectal cancer(CRC) survival over the last 20 years.METHODS:We compared two groups of consecutive CRC patients that were prospectively recruited:Group Ⅰincluded 1990 patients diagnosed between 1980 and 1994.GroupⅡincluded 871 patients diagnosed in 2001.RESULTS:The average follow up time was 21 mo(1-229)for GroupⅠand 50 mo(1-73.4)for GroupⅡ.Overall median survival was significantly longer in Group Ⅱthan in GroupⅠ(73 mo vs 25 mo,P<0.001)and the difference was significant for all tumor stages.Post surgical mortality was 8% for GroupⅠand 2% for Group Ⅱ(P<0.001).Only 17% of GroupⅠpatients received chemotherapy compared with 50% of GroupⅡpatients(P<0.001).CONCLUSION:Survival in colorectal cancer patients has doubled over the past 20 years.This increase seems to be partly due to the generalization in the administration of chemotherapy and to the decrease of post surgical mortality.