Screening for colorectal cancer using the Hemoccult II stool guaiac slide test

Following a series of educational spots on colorectal cancer shown on a local television news program, stool guaiac slide kits (Hemoccult II; Smith Kline Diagnostics) were distributed in shopping malls in Erie County, New York during a 3-day period in February 1982. The tests kits were sold for $1.00 a piece. A total of 8711 persons purchased test kits and 3822 persons (44%) returned slides for testing. One or more slides were positive in 107 persons (2.8%). Ninety of the 107 positive screenees (84%) saw a physician for further evaluation after screening. Eighteen positive screenees had no evidence of pathology which could cause blood in their stool when evaluated by a physician, yielding an overall false-positive rate of less than 0.5%. Seven new cases of colorectal cancer were found through screening. Five of the seven cancers (71%) detected were localized disease (Dukes' Stage A, B1 or B2), and four cases had no symptoms of disease prior to diagnosis. The findings from this study suggest that screening for fecal occult blood using the stool guaiac slide test is effective in detecting some colorectal cancers at an early stage of disease, often before symptoms appear.