Colorectal Cancer Screening Using Immunochemical Fecal Occult Blood Test

Fecal occult blood test (FOBT) screening has been shown to decrease the incidence and mortality of colorectal cancer (CRC). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the immunochemical fecal occult blood test (i-FOBT) in diagnosing CRC were assessed among the patients in a tertiary referral hospital in Malaysia. A total sample of 814 patients aged 16 to 85 years old who performed i-FOBT and endoscopic screenings was obtained. The patients were recruited for a retrospective investigation. Sensitivity, specificity, PPV, and NPV were derived for the CRC screenees. Out of the 814 patients screened using i-FOBT, half of them were above 59 years old (49.6%), and 36% had positive i-FOBT. Gender distribution was almost equal, where 53.4% of the patients were female, and 46.6% were male. Majority of the patients were Malays (56.6%), followed by Chinese (24.0%), Indians (16.5%), and others (2.9%). Among the 71 patients referred for colonoscopy, 57.7% and 42.3% corresponded to positive and negative i-FOBT cases, respectively. Polyps were found to be most common among the patients (25.6%), 7.0% were found positive for invasive CRC, and 35.2% had normal colonoscopic findings. There was a significant association between colonoscopic finding and positive i-FOBT (p=0.001). The sensitivity, specificity, PPV, and NPV for CRC detection were 66.7%, 43.0%, 9.8%, and 93.3%, respectively. The results indicate that i-FOBT is a useful tool in the detection of abnormalities in the lower gastrointestinal tract and therefore serves as a cornerstone for potential large-scale screening programmes.

Clinical value of immunochemical fecal occult blood test in diagnosis of colorectal diseases / 中国医师进修杂志

ObjectiveTo discuss the value of immunochemical fecal occult blood test (IFOBT) in diagnosis of colorectal diseases.Methods Two hundred and fifty-one patients who taken IFOBT and chemical fecal occult blood test(CFOBT) from January 2008 to August 2011 were enrolled in this study.They were definitely diagnosed by total colonoscopy combined with pathology.ResultsThe positive rate of IFOBT and CFOBT in colorectal cancer patients was 100.0％(57/57) and 84.2％(48/57),there was significant difference (P ＜ 0.05).The positive rate of IFOBT and CFOBT in colorectal polyp patients was 38.6％ (32/83) and 10.8％(9/83 ),there was significant difference(P ＜ 0.05 ).The positive rate of IFOBT and CFOBT in inflammatory bowel disease patients was 100.0％(31/31) and 80.6％(25/31),there was no significant difference (P ＞ 0.05).Thepositive rate of IFOBT and CFOBT in non-specific enteritis patients were 86.8％ (33/38) and 73.7％ (28/38),there was no significant difference (P ＞ 0.05 ).The positive rate of IFOBT and CFOBT in normal colorectal cases was 2.4％(1/42) and 19.0％(8/42),there was siguificant difference (P ＜ 0.05).ConclusionsIFOBT is better than CFOBT in diagnosis of colorectal cancer and colorectal polyp.IFOBT has lower false positive rate.