Sequential screening in the early diagnosis of colorectal cancer in the community

Abstract

Background: Colorectal cancer (CRC) is the third most prevalent type of cancer in the world. Its prognosis is closely related to the disease stage at the time of diagnosis. Early detection of symptomless CRC or precursor lesions through population screening could reduce CRC mortality. However, screening programs are only effective if enough people are willing to participate. The incidence of CRC has a significantly increasing trend in China. Objective: Evaluation of the necessity of screening colonoscopy for community fecal occult blood-positive patients and exploration of the differences in the epidemiology of colorectal adenomas (CRA) and CRC of community screening patients and patients with different symptoms. Methods: We selected the 40–79 years age group of healthy people in the community of the Fengxian District of Shanghai who had two consecutive fecal occult blood and screening colonoscopies completed in our hospital between June 1, 2014 and October 31, 2014 as the screening group. Patients in the same age group with different symptoms (such as abdominal pain, bloody stool, diarrhea, change in bowel habits, weight loss, anemia, etc.) who had completed colonoscopy in our hospital during the same period comprised up the control group. Differences in the detection rates of colorectal polyps and CRC in the two groups and differences in the detection rates of CRA and early CRC between the two groups were compared. Results: There were 2251 patients in the colonoscopy screening group and 1836 patients in the control group. The colorectal polyps detection rates of the two groups were 19.46% (438/2251) and 21.95% (403/1836), respectively, and the difference was not statistically significant (p = 0.052). The CRC detection rates of the two groups were 0.8% (18/2251) and 2.02% (37/1836), respectively, the difference of which was statistically significant (p = 0.001). The detection rates of CRA were 17.73% (399/2251) and 19.88% (365/1836), respectively, which was not statistically significantly different (p = 0.083). Finally, the detection rates of early CRC were 0.36% (8/2251) and 0.44% (8/1836), respectively, which was not statistically significantly different in the two groups (p = 0.803). Conclusion: The detection rates of CRA among community screening patients and patients with different symptoms were not different. However, the detection rate of CRC in community screening patients was lower than that of the patients with different symptoms. Therefore community colonoscopy screening of fecal occult blood-positive asymptomatic healthy people is necessary, as it can help with the early detection and treatment of CRA.