Brief Answer:
you are free of trouble but on the radar

Detailed Answer:
Thank you for asking

Lynch syndrome is Hereditary non polyposis colorectal Cancer and hMLH1 is one of the seven types of Mismatch repair of the genes found on autosomal dominant chromosomes thus making both genders equally vulnerable in family.

Your labs came negative so it means you are free of the trouble mean while but you are more vulnerable to it compared to the rest of the people. not everyone who inherits the gene for hereditary nonpolyposis colorectal cancer (HNPCC) develops colorectal cancer, individuals with Lynch syndrome have a 70-80% lifetime risk of developing colon cancer. You don't have lynch either so your odds are very low than your family members but higher than rest of the community .

You are already 45 and free of troubles which is good news as Colorectal cancer in persons with hereditary nonpolyposis colorectal cancer (HNPCC) occurs at an earlier age than in the general population. In persons with hereditary nonpolyposis colorectal cancer (HNPCC), the average age of polyp onset is in the late second decade and early third decade of life. The average age of colorectal cancer onset is 44 years in members of families that meet the Amsterdam criteria compared with age 60-65 years in the general population .

As your family fulfills the amsterdam and bethesda criteria for HNPCC / lynch syndrome , so that makes you vulnerable. You need to be in constant touch with your gastroenterologist with annual and or bi annual screening for the syndrome. with screening tests like immunohistochemistry (IHC) testing, MSI testing (usually used as a prescreening test), and DNA analysis (considered unnecessary, expensive, and time-consuming and to be used only if previous labs came negative).

Also surveillance of other associated tracts like genitourinary and hepatobiliary tracts need to be monitored to prevent any chaos as lynch may involve them too.

Nut shell, you are lucky but more prone than the rest of the community and that makes you on surveillance check and necessary for early and prompt detection in worst case scenario.

Meanwhile keep an eye on your lifestyle and following symptoms, if any appear better consult your gastroenterologist promptly.

Changes in bowel habits (eg, constipation or diarrhea that persists for longer than several days)
Visible or no blood in stool (positive fecal occult blood test)
Black, tarry stool (may represent bleeding above the rectum)
Iron deficiency without an identifiable cause
Abdominal pain, cramps, or frequent feeling of distention (or bloating) in the abdominal or bowel region
Fatigue or weakness
Decline in appetite
Unexplained weight loss

I hope it helps. Take good care of yourself and dont forget to close the discussion please.

May the odds be ever in your favour.

Regards
Khan

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