A high risk population consisting of 3034 people with history of rectal polyps or ulcers were screened for colorectal neoplasia with Reverse Passive Hemagglutination Fecal Occult Blood Test (RPHA FOB) and 60 cm fibero...A high risk population consisting of 3034 people with history of rectal polyps or ulcers were screened for colorectal neoplasia with Reverse Passive Hemagglutination Fecal Occult Blood Test (RPHA FOB) and 60 cm fiberoptic colonoscopy. Among 2553 subjects (84.1%)who completed both tests, 11 cases of colorectal malignancies and 465 cases of polyps were detected.Using colonoscopic finding and histopathological examination as the 'gold standard' of diagnosis, results showed that FOB positivity of polyps was related to their size, macroscopic appearance and surface features but no correlation between bleeding of polyps and their location, numbers, pathological types were found. In this study the sensitivity of RPHA in screening of colorectal malignancy was 63.6% (7/11), while that for polyps was only 21.1% (98/465) . For screening of colorectal neoplasia (cancer+polyps) the overall sensitivity and specificity of RPHA FOB were 22.1% and 82.4%, the positive and negative predictive values were 22.3% and 82.2% respectively. Amoug 465 polyps there were 195 adenomas, further analysis showed that villous and tubulovillous adenomas had higher intestinal bleeding rate (FOB positive)than tubular type (45.5%,30.0% and 17.8% respectively, X2=5.8, p=0.05). The results indicate that although the sensitivity of RPHA FOB in screening for colorectal polyps was generally low, but about 40% (8/21) of villous and tubulovillous adenoma which present higher tendency of malignant transformation can be detected by RPHA FOB as a screening Procedure. So the authors suggest that screening of colorectal neoplasia be not only a procedure of secondary prevention but also a measure of primary prevention for colorectal cancer.Accepted March 22, 1994展开更多
文摘A high risk population consisting of 3034 people with history of rectal polyps or ulcers were screened for colorectal neoplasia with Reverse Passive Hemagglutination Fecal Occult Blood Test (RPHA FOB) and 60 cm fiberoptic colonoscopy. Among 2553 subjects (84.1%)who completed both tests, 11 cases of colorectal malignancies and 465 cases of polyps were detected.Using colonoscopic finding and histopathological examination as the 'gold standard' of diagnosis, results showed that FOB positivity of polyps was related to their size, macroscopic appearance and surface features but no correlation between bleeding of polyps and their location, numbers, pathological types were found. In this study the sensitivity of RPHA in screening of colorectal malignancy was 63.6% (7/11), while that for polyps was only 21.1% (98/465) . For screening of colorectal neoplasia (cancer+polyps) the overall sensitivity and specificity of RPHA FOB were 22.1% and 82.4%, the positive and negative predictive values were 22.3% and 82.2% respectively. Amoug 465 polyps there were 195 adenomas, further analysis showed that villous and tubulovillous adenomas had higher intestinal bleeding rate (FOB positive)than tubular type (45.5%,30.0% and 17.8% respectively, X2=5.8, p=0.05). The results indicate that although the sensitivity of RPHA FOB in screening for colorectal polyps was generally low, but about 40% (8/21) of villous and tubulovillous adenoma which present higher tendency of malignant transformation can be detected by RPHA FOB as a screening Procedure. So the authors suggest that screening of colorectal neoplasia be not only a procedure of secondary prevention but also a measure of primary prevention for colorectal cancer.Accepted March 22, 1994
