Colorectal cancer is the second leading cause of cancer death in the United States.
According to the CDC, every year about 140,000 Americans are diagnosed with
colorectal cancer and over 500,000 die from it. That being said, it should come as no
surprise that colon cancer is a major GI topic in the ABIM exam.
Remember these Autosomal Dominant conditions and their management:
Familial adenomatous polyposis (FAP) – caused by a mutation in the
APC gene
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K N O W M E D G E
annual flex sig beginning at age 10-12, and colectomy should be
considered when polyposis is detected
Hereditary nonpolyposis colorectal cancer (HNPCC), or Lynch syndrome
– caused by a mutations in the MLH1 and MSH2 mismatch repair genes
colonoscopy every 1 to 2 years starting at age 20-25 years or 10
years before the age at diagnosis of the youngest family member
with colon cancer
Peutz-Jeghers syndrome – caused by a germ line mutation in the STK11
gene
Juvenile polyposis syndrome – caused by a germ line mutation of the
SMAD4 gene