Phase Ⅰ is a cross-sectional study to record selected information and biospecimen of more than 250 sporadic colorectal adenoma cases (200 cases with convetional adenomas, 25 cases with hyperplasticpolyps and 25 cases with TSA/SSAs), 50 cases of sporadic colorectal cancer (early cancer), 50 cases with familial inherited colorectal cancer (FAP and LS) or healthy controls.~Phase Ⅱ is a nested case-control study. A total of 250 patients with sporadic colorectal cancer (early stage cancer) or sporadic colorectal adenoma will be included in Phase Ⅱ and regular follow-up to observe the recurrence and progress after resection of the lesions of colorectal adenomas.~The end point of the study is the recurrence of bowel adenoma or carcinoma and follow-up time is five years. After the observation, each case with the study outcome was matched with corresponding controls in a 1:1 ratio for further analysis according to the conditions such as age and gender.(Due to the particularity of single-cell sequencing, all specimens that meet the test requirements were sent for examination, and a nest-type case-control design was not adopted.)
This study focused on the key nodes, molecular events and regulatory mechanisms of intestinal microecological disorders that affect the malignant transformation of intestinal epithelial cells into tumors during the occurrence and development of colorectal cancer.