Malignant Colorectal Polyp

The purpose of this study is to learn more about malignant colorectal polyps (early colorectal cancers removed during colonoscopy) and the risk that cancer remains, comes back, or spreads after the polyp is removed. The researchers also want to understand how patients and doctors make decisions about whether to have surgery or to be followed closely without surgery after a malignant polyp is removed. This is an observational study. Participants will not receive any study treatment, and their care will be decided by them and their doctors as usual. The researchers will collect information from participants' medical records, including test results, imaging scans, lab work, and pathology reports, and may collect images from colonoscopy and copies of the pathology slides of the polyp. Participants will be asked to complete short questionnaires about how they view their risk and what influenced their treatment decision. The researchers will follow participants' health over time through their regular doctor visits; if no visit is scheduled, a member of the study team will contact participants by phone at 1, 3, and 5 years after they join the study.