Young-Onset Colorectal Cancer

This study investigates the genetic factors that may influence the risk of developing colorectal cancer at a young age. Finding genetic markers for colorectal may help identify patients who are at risk of colorectal cancer. Studying individuals and families at high risk of cancer may help identify cancer genes and other persons at risk.

Inclusion Criteria: * PATIENTS: MDACC patients who have adenocarcinoma of the colon or rectum, diagnosed between ages 18 through 50 (young-onset), or diagnosed at age 51 through 80 (later-onset) * PATIENTS: Patient must have sufficient command of the English language and mental capacity to provide consent * FAMILY MEMBERS: Be a parent, sibling or child (first degree blood relative) of a registered MDACC patient meeting eligibility criteria above * FAMILY MEMBERS: Have sufficient command of the English language and mental capacity to provide consent * FAMILY MEMBERS: Family member must be at least 18 years of age at the time of study registration