My sister age 62 had a recent colonoscopy that discovered a 3 cm pre-cancerous polyp. I am 55 and had my first colonoscopy right on time at 50. Is there a greater risk for me now that there is a family history? What are the recomendations for her children?

Since your sister (a first degree relative - a parent, sibling or child) had a pre-cancerous polyp but was under age 60 at the time of diagnosis, and you have already had a screening colonoscopy, you can now get colonoscopies at the same intervals as the general population. The recommendations for her children are to start screening colonoscopies at the age of 40.