Hereditary Cancer Center
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With its foundation in Hereditary Non-polyposis Colorectal Cancer (HNPCC) or the Lynch Syndrome, the Colon Resource here at the Hereditary Cancer Institute is currently studying over 450 families with over 90 families identified with specific genetic mutations.

Please refer to the family study process for the steps that are taken for a family to become involved in the Colon Resource and the various studies. (family study process page).

After a family has been determined to have a pattern of hereditary cancers, one of the following syndrome diagnoses would be assigned to the family.

Hereditary Non-Polyposis Colorectal Cancer (HNPCC):

  1. Colon Cancer occurs in multiple family members in more than one generation.
  2. Average Age of Diagnosis is 44.
  3. Cancer occurs more often on the right side of the colon.
  4. Females at much greater risk for endometrial & ovarian cancer.

Familial Adenomatous Polyposis (FAP):

  1. Colon Cancer occurs in a first or second degree relative.
  2. Average Age of Diagnosis is 40, but polyps can begin to appear between the ages of 7 and 36.
  3. The presence of greater than 100 colorectal polyps.

Hereditary Diffuse Gastric Cancer (HDGC):

  1. Stomach Cancer occurs in multiple family members in more than one generation.
  2. Cancer cells grow within the lining of the stomach rather than growing outward into the stomach.

Families may be advised about available genetic tests to determine a definite hereditary cancer diagnosis within the family. Individuals in these families are provided with surveillance and screening recommendations based on their family history and syndrome diagnosis. Information will continue to be updated on additional family members. Each family is assessed on an individual basis with all factors taken into account; therefore, these definitions are not strictly adhered to if other factors come into play.

Genes

Genetic Features

Clinical Features of Carriers

 
MLH1

  • Discovered in 1994
  • Located on Chromosome 3
  • Mismatch Repair Gene
  • Accounts for approx. 45% of
    hereditary colon cancers
  • 25-82% lifetime risk of developing colon cancer in men and women equally
  • 20-42% lifetime risk of developing endometrial cancer in women
  • 12% lifetime risk of ovarian cancer in women
  • Increased chance of kidney and ureter, stomach, biliary tract, brain, and small intestine cancer in men and women equally 

MSH2

  • Discovered in 1994
  • Located on Chromosome 2
  • Mismatch Repair Gene
  • Accounts for 35% of hereditary
    colon cancers
  • 20-82% lifetime risk of developing colon cancer in men and women equally
  • 20-61% lifetime risk of developing endometrial cancer
  • 12% lifetime risk of ovarian cancer in women
  • Increased chance of kidney and ureter, stomach, biliary tract, brain, and small intestine cancer in men and women equally

If a non-hereditary syndrome diagnosis is made, surveillance and screening recommendations based on family pedigree information are sent to family members who are at increased risk due to family history of cancer. Update of family information by participating family members will be continued in order to determine if a hereditary could pattern develop in the future.


We are constantly accepting new families that have a family history of colon cancer. If you are unsure if your family history demonstrates a hereditary pattern, we invite you to give us a call and we can briefly review it for you. The HNPCC resource has several ongoing studies in which appropriate individuals are invited to participate. Please click on the links above for a brief summary of these studies. If you would like further details regarding any study please give Vicki a call at our toll-free number 1-800-648-8133 , ext 2312.