Accuracy of fecal occult blood screening for colorectal neoplasia. A prospective study using Hemoccult and HemoQuant tests D. A. Ahlquist, H. S. Wieand, C. G. Moertel, D. B. McGill, C. L. Loprinzi, M. J. O'Connell, J. A. Mailliard, J. B. Gerstner, K. Pandya and R. D. Ellefson Division of Gastroenterology, Mayo Clinic, Rochester, MN 55905.
OBJECTIVES--To define the validity of fecal blood as a marker for colorectal neoplasia in the screening setting and to compare yields by Hemoccult and HemoQuant fecal occult blood screening tests. DESIGN--A multicenter masked comparison of fecal blood test results against structural colorectal evaluations and longitudinal follow-up, serving as criterion standards, in nonreferred subjects at risk for colorectal neoplasia. SETTING--Communities, primary care centers, referral centers. PARTICIPANTS--Two groups: (1) 1217 patients aged at least 18 years undergoing routine structural surveillance evaluations following curative resection of a colorectal tumor and (2) 12312 relatives of colorectal cancer patients aged at least 50 years. INTERVENTIONS--Blinded Hemoccult II and HemoQuant testing on three mailed-in stool samples per subject. MAIN OUTCOME MEASURE--Sensitivity of fecal blood tests for colorectal neoplasia. RESULTS--In the postresection group, surveillance evaluations revealed 46 malignant colorectal neoplasms and 402 polyps. At matched specificity, sensitivity of either test for cancer was 26% (95% confidence interval, 13% to 39%). Hemoccult was positive in 21% of intraluminal recurrences, 33% of all new primary tumors, and 29% of Dukes A or B cancers; HemoQuant was elevated in 24%, 28%, and 29%, respectively. Sensitivity for polyps 1.0 cm or larger was 13% by Hemoccult and 11% by HemoQuant. In the group of relatives, estimated sensitivity for cancer at 1 to 3 years of follow-up was 25% to 33% by Hemoccult, not significantly different from the 29% to 43% by HemoQuant. CONCLUSIONS--Based on our observations in the screening setting, fecal blood appears to be a poor marker for colorectal neoplasia. Most cancers and the vast majority of polyps will be missed. Hemoccult and HemoQuant are similarly insensitive.
ACS Updates Colorectal Screening Guidelines ACS Updates Screening Guidelines for Colorectal Cancer
Article date: 2001/02/14 An American Cancer Society (ACS) panel of experts recently concluded that two screening tests for colorectal cancer ? a fecal occult blood test and a flexible sigmoidoscopy ? are more effective than either test alone. But after discovering that too many patients would not or could not have both tests and were skipping the screening process altogether, the ACS updated its guidelines to make one thing perfectly clear: if you don?t get both tests, at least get one of them.
"Many primary care physicians and others were telling us that they were not prepared to offer sigmoidoscopy," says Robert Smith, PhD, ACS Director of Screening and lead author of the new guidelines, which are published in the January/February 2001 issue of CA -- A Cancer Journal for Clinicians.
Smith says that this led to concern that the complexity of the double screening process was leading to inertia, and no screening at all was taking place.
"We know that fecal occult blood testing (FOBT) alone is effective," he says. "We know that flexible sigmoidoscopy alone is effective. We believe that the data show that the combined testing is more effective. But the most important thing that anyone, provider or patient, can do now is at least do something."
FOBT is an inexpensive, noninvasive test that checks a patient
Because compliance is so low for colonoscopy about 50% actually follow the guideline... and the expense of colonoscopy is another issue, so many can not afford it, remember you need to be drugged and then they are prepared to remove polyps and do pathology... very expensive. They need another screening technique for the masses. I think it needs to be compared more to the Fecal Occult blood screen that is recommended annually after 50 years old.