This study aims to determine the performance of the Exact IBD-ACRN surveillance test to detect colorectal cancer (CRC) and colorectal neoplasia in patients with inflammatory bowel disease (IBD). Patients with an IBD diagnosis for at least eight years or diagnosis of primary sclerosing cholangitis (PSC) and who are eligible for CRC screening are eligible to participate in this study. Enrolled subjects will collect a stool sample for the Exact IBD-ACRN surveillance test. Subjects must have undergone colonoscopy no more than 90 days prior to enrollment and will undergo colonoscopy or surgical intervention within 120 days of enrollment. Tissue diagnosis of CRC will be established by histopathologic examination.

This is a prospective, cross sectional, multi-center study to determine the sensitivity and specificity of the Exact IBD-ACRN surveillance test for detecting CRC alone and in combination with high grade dysplasia (HGD) and low grade dysplasia (LGD) associated with IBD and advanced adenoma in IBD patients with disease duration greater than 8 years or PSC diagnosis. Enrolled subjects will provide a single stool sample for the Exact IBD-ACRN surveillance test, no sooner than 7 days following their most recent pre-enrollment colonoscopy, within 30 days of enrollment and prior to initiating bowel prep for either the post-enrollment colonoscopy (surveillance or repeat), or surgical intervention. Stool samples will be tested using the Exact IBD-ACRN surveillance test and results compared to the colonoscopy and corresponding diagnostic histopathology results from biopsied, and any subsequently excised, lesions to establish sensitivity and specificity of the Exact IBD-ACRN surveillance test. All post-enrollment colonoscopies or surgical interventions must be performed within 60 days of enrollment.

The primary objective of this study is to determine the sensitivity and specificity of the Exact IBD-ACRN surveillance test for CRC in IBD patients with disease duration of at least eight years or diagnosis of PSC. Tissue diagnosis of CRC will be established by histopathology examination. The secondary objective is to determine the sensitivity and specificity of the Exact IBD-ACRN surveillance test to detect ACRN in IBD patients with disease duration of at least eight years or diagnosis of PSC.

Enrollment will continue until at least 35 CRC; 15 HGD and 315 negative subject samples have been obtained. There is no specific recruitment goal for IBD associated LGD or LGD associated with advanced adenoma (AA).

Inclusion Criteria:

• Male or female 18-84 years of age, inclusive.
• Diagnosis of IBD or a diagnosis of PSC with IBD prior to enrollment date of this study.
• Must be a candidate for a surveillance colonoscopy, with the intention of CRC/dysplasia surveillance, or a candidate for surgical intervention based on prior histological confirmation of HGD or CRC.
• Written informed consent document signed and dated by the subject or legally acceptable representative.

Exclusion Criteria:

• Any condition that in the opinion of the investigator should preclude participation in the study.
• A history of aerodigestive tract cancer.
• Prior colorectal resection, except ileocolic resection in Crohn's disease patients.
• IBD limited only to the rectum and without a concurrent PSC diagnosis.
• Subject has participated in any clinical study within the previous 30 days wherein an investigational compound or device was, or may be, introduced into the subject.

Subjects who have diagnosed IBD and are undergoing a colorectal cancer surveillance program. Also, have either a histopathological diagnosis of high grade dysplasia or colorectal cancer resulting from colonoscopy preceding enrollment or for whom a surveillance colonscopy is indicated.