Not everybody with Lynch syndrome develops cancer – but there is a heightened risk. The most common risk is a higher chance of developing cancer in the linings of the bowel or uterus.
Roughly 50% of people with Lynch syndrome will develop bowel cancer before the age of 70. In contrast, 6% of the general population will develop bowel cancer by the age of 75. The average age for a bowel cancer diagnosis is 45 for those with this syndrome, compared with 67 years in the general population.
Men with Lynch syndrome have a 38% chance of developing bowel cancer and a 7% chance of developing stomach cancer during their lifetime.
Women with the syndrome have a 31% chance of developing bowel cancer, a 33% chance of uterine (endometrial) cancer, a 9% chance of ovarian cancer and a 7% risk of stomach cancer.