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.

PRIMARY OBJECTIVES:

I. To define the clinical phenotype of young-onset versus (vs.) later onset colorectal cancer (CRC), including clinicopathologic characteristics, tumor molecular markers, family history, and associated lifestyle/environmental factors.

II. To examine germline genetic alterations in patients with young-onset (diagnosed between age 18 and 50), CRC and those of their first-degree relatives, in comparison to those in patients with later-onset (diagnosed at age 51 or older) CRC.

III. To determine the frequency of the mutations and pattern of inheritance of the mutations identified above in this patient population.

IV. To correlate molecular findings to clinical endpoints of survival and disease recurrence and/or progression in patients with young-onset vs. later-onset CRC.

V. To compare the treatments received by patients with young-onset vs. later-onset CRC and their subsequent survivorship experiences.

OUTLINE:

PATIENTS: Patients complete questionnaires over 30-50 minutes about work, family history, medical history, health habits, and experience as a cancer survivor (quality of life, well-being, concerns, types of health care, and follow-up care received). Active patients, who have undergone treatment at MD Anderson Cancer Center within the past year, complete additional questionnaires at enrollment, 6 months, 12 months after treatment completion, and then every years for up to 6 years. Also, active patients who are consented to the study more than 5 years from surgery, they may complete the survivorship questionnaire once. Patients medical records are also reviewed.

FAMILY MEMBERS: Participants complete questionnaires over 10-15 minutes. Participants also undergo collection of blood or saliva samples once.

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

MD Anderson Cancer Center (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) and their family members