Collection of Information to Better Understand Young Onset Colorectal Cancer

Inclusion Criteria: Participant Inclusion Criteria for database and questionnaire (YOGI) * Histological or cytological diagnosis of gastrointestinal cancer * 18 - 49 years old at time of consent * No Known hereditary CRC or other cancer predisposition syndrome (stool collection cohort only) * No history of inflammatory bowel disease (stool collection cohort only) * No prior diagnosis of gastrointestinal cancer (stool collection cohort only) Participant Inclusion Criteria for database and questionnaire (Controls) * Histological or cytological diagnosis of colorectal adenocarcinoma * No previous treatment for CRC (including surgery, chemotherapy, immunotherapy or radiation) * Age 50 or older at time of consent * No Known hereditary CRC or other cancer predisposition syndrome * No history of inflammatory bowel disease * No prior diagnosis of CRC