A Novel Oral Synbiotic Formula in Reducing Advanced Adenoma Recurrence and Colorectal Neoplasia-related Bacterial Gene Markers

Inclusion Criteria:

* Subjects who have advanced colorectal neoplasia\* removed and confirmed by histopathology;
* They have received high quality colonoscopies before or during endoscopic resection (defined as a full colonoscopy with successful caecal intubation, and a Boston Bowel Preparation Scale ≧2 in each colonic segment) with no residual colorectal neoplasia;
* Aged 18-90 years old;
* Written informed consent obtained

  * An advanced colorectal neoplasia is defined as an advanced adenoma, sessile serrated lesion or non-invasive colorectal cancer (stage Tis or T1a). Advanced adenoma is defined as an adenoma larger than 10mm, and/or with villous component ≥20%, and/or harboring high grade dysplasia.

Exclusion Criteria:

* Known residual colorectal neoplasia not removed (except hyperplastic polyps);
* Contraindications to endoscopic resection due to deep submucosal invasion (stage T1b or above);
* Prior surgical resection of colon;
* Personal history of hereditary polyposis syndrome or inflammatory bowel disease;
* Known pregnancy or lactation;
* Immunocompromised status (e.g. on immunosuppressants (except 5-aminosalicylic acid or short term use of corticosteroids \<4 weeks), on chemotherapy, bone marrow or solid organ transplant, human immunodeficiency virus, congenital immune deficiency);
* Advanced comorbid conditions (defined as American Society of Anesthesiologists grade 4 or above);
* Refusal to undergo surveillance colonoscopy.