heditary non-polyp colon/rectal cancer - Cancer: Colon Message Board

ladyanne · 11-11-2001, 07:43 PM

Has anyone experienced or heard of HNPCC. It is a mutated gene that cause cancer early in a person and can come in several different forms and grows fast. My mom is testing for it after second round of colon cancer and she appears to fit the MO. Am researching all I can so please let me know.

11-11-2001, 11:36 PM

Hi, Yes I've heard of HNPCC. It is the cause of between 4-11% of colorectal cancer. It's also refered to as Lynch Syndrome, which may aid you in your search for answers.

The majority of HNPCC is caused by a germline defect in DNA mismatch repair (MMR) gene. MMR normally serves as the housekeeper to maintain genomic stability by correcting errors arising in DNA replication. Genetic defect in MMR gene leads to genomic instability and the development of HNPCC. Two of the human MMR genes, hMLH1 and hMSH2, are the major cause of HNPCC

A criterea is used by physcians to determine if further testing is needed of an individual with colorectal cancer called the Amsterdam Criterea.
1)at least 3 relatives with colorectal cancer
2)one affected person is a first degree relative of the other two
3)at least two successive generations affected
one affected person diagnosed prior to age 50

For people with HNPCC it usually means:
mean age 45
Tumors predominate in right colon
Increased synchronous and metachronous colorectal neoplasms
Increased incidence of extracolonic neoplasms
Endometrial, small bowel, gastric, renal pelvis and ureter, ovarian, skin possibilities.

If you test positive, it is recommended to get a colonoscopy every 1-3 years, starting at age 21. This increases your chances tremendously of finding it early. It is also recommended that family members are scheduled for colonoscopy at 21.

Clinical and molecular genetic knowledge about HNPCC is now available to physicians, and should enable them to provide highly targeted surveillance and management for patients with a high cancer risk. Genetic counseling can prove lifesaving.

ChelOneil · 03-07-2002, 12:20 PM

Yes, that is very common in my family unfortunately.

My great grandfather died at age of 46
My grandfather died at age of 46
My great aunt died in her 30's
My great uncle died in his 30's
My cousin died at 22
My uncle died at the age of 46 and
My mom had cancer at the age of 32, she is the only one that survived and is still living.

I am 29 and get colonoscopy's every 18 months, the doctor said if the next one is clear then I can go every 2 years.

My cousin who is 19 also has to go every 18 months because her mom is my cousin who died of it at the age of 22.

There are some other family members who have had it, I just haven't really gone that far back.

sandyschaefer · 04-04-2005, 12:26 PM

I just got the final diagnosis of HNPCC last week--I have a mutation in the MSH6 gene. My family is all in the process of getting tested right now.

Found out there is a 50% chance that I passed it on to my children. If my children do not have it, they cannot pass it on.

I would suggest that you meet with a genetic counselor--they are very helpful. Your Dr. should be able to suggest one--or your Mom's oncologist could suggest one. There is lots of info. on the internet about it. In fact, by the time I met with the genetic counselor, I had most of the information that I needed. The counselor can help you with some surveilance suggestions.

Good luck.