Recent discovery of a novel assay that is more likely to be beneficial for patients with Lynch Syndrome. Investing into current version of Cologuard test would provide little clinical benefit.

This study is aiming to enroll 90 patients with genetically confirmed Lynch Syndrome (LS) from Geisinger's High Risk Colorectal Cancer Clinic (HRC). Upon enrollment in the study, a Cologuard test will be ordered and the results will be blinded until data analysis. Patients enrolled in the study will also undergo a colonoscopy as part of their routine HRC visit.

The primary aim is to perform a pilot study to gain information toward the implementation of a larger prospective study that will compare the performance of Cologuard with the gold-standard colonoscopy in identifying advanced adenomas and colorectal cancers in LS. Data regarding rate of consent, and adherence to the protocol will be recorded. Since patients with known genetic predisposition to cancers tend to view screening tests more positively than the general population, a second aim of the study is to evaluate patient satisfaction with bowel preparation, colonoscopies, and Cologuard testing. Up to 90 individuals with genetically confirmed LS will be recruited via Geisinger's HRC to complete a goal of 90 Cologuard studies. Upon enrollment, Cologuard will be ordered by the study team at no cost to the subject and will be completed according to the standard instructions for use. Results will be securely obtained and blinded until the time of data analysis. Subjects will undergo colonoscopy as part of their routine HRC visit. Results from the colonoscopy (and biopsy as indicated) will be retrieved from the Electronic Health Record (EHR) and documented in a research-associated spreadsheet. If repeat colonoscopy is clinically indicated, repeat Cologuard may be completed if the subject meets inclusion criteria.

Inclusion Criteria:

• Patients age 18-89
• Diagnosis of genetically confirmed LS
• Scheduled for standard of care colonoscopy within 60 days of enrollment

Exclusion Criteria:

• Diagnosis of other inherited genetic disorders that increase risk for Colorectal Cancer (CRC) (Familial Adenomatous Polyposis (FAP), Cowden's syndrome, Turcot syndrome, Gardner syndrome, and Peutz-Jeghers syndrome)
• Diagnosis of other inherited Inflammatory bowel disease (i.e. Crohn disease, ulcerative colitis)
• Others with elevated risk of CRC outside of the inclusion criteria (i.e. ≥2 first-degree relatives who have been diagnosed with CRC without a defined inherited genetic disorder, Hereditary Non-Polyposis Colon Cancer (HNPCC) without genetic confirmation of LS)
• Participation in any interventional clinical study within the previous 30 days
• Personal history of CRC not in full remission (5 consecutive cancer-free years)
• Current active treatment with chemotherapy
• Treatment with chemotherapy within 12 months prior to consent date

Adult patients being followed in the HRC with a diagnosis of LS