The lady I went to lunch with yesterday has Lynch. She didn't know this until she was 60, because while her mother died in her fifties it was presumed to be lifestyle. She only found out when her 30 year old son was diagnosed with very advanced bowel cancer that had metastised into bladder. He had significant chemo before they could even attempt surgery. Six months later he had a 12 hour surgery that took so much bowel and bladder. He also experienced nerve damage in his arm leaving it paralysed because of the surgical process where he was suspended, to operate.
It's been three years now. He goes into hospital several times a year for issues of kidney function, infections, stent repairs, etc etc. He married a few months later (engaged before the discovery) and they were successful in having a child through IVF. Every embryo is screened. They had a boy and are trying for a second. However last round (last week) four of the 6 potential embryos had Lynch syndrome. Along with the cost of IVF it costs them $800 per embryo to be screened.
Genetic testing of my friends family found that only she, in a family of four siblings, and her son, in a total of around 10 cousins, had the syndrome.
My friend now has had a preventive hysterectomy and has constant colonoscopies and breast scans.
It's a devasting one. And Covid has been awful for them. So much so that even though I had no symptoms and no known contacts, I did a RAT before meeting them. And we ate outside. Masks worn inside when ordering.