II. Epidemiology
- Prevalence: 1 in 440 persons (U.S.)
- Diagnosed on average by age 45 years
- Lifetime Colon Cancer risk: 75-80%
- Autosomal Dominant condition
III. Pathophysiology
- Rapid progression from advanced adenoma to Colorectal Cancer
IV. Associated Conditions
-
Colon Cancer
- HNPCC is the most common cause of inherited Colorectal Cancer (2-4% of cases)
- Endometrial Cancer
- Gastric Cancer (subset of families)
V. Diagnosis
- Patient with first degree relative with Colorectal Cancer diagnosed before age 50 years OR
- Genetic Testing
VI. Management: Colorectal Cancer Screening
- Counseling to consider Genetic Testing
- Early Screening
- Colonoscopy starting at age 25 years (or 5 years earlier than youngest Colorectal Cancer relative)
- Repeat Colonoscopy every 1-2 years
-
Genetic Testing positive or No Genetic Testing
- Colonoscopy every 2 years until age 40
- Colonoscopy yearly after age 40
- Continue surveillance until age 75 years old
VII. Management: Gastric Cancer Screening
- Indications
- HNPCC patients with Family History or Genetic Testing in which Gastric Cancer is a risk
- Upper endoscopy protocol
- Start at age 50 years (or five years before the youngest case)
- Repeat every 2 years until age 75 years