First of all, make sure you are going to a board-certified gastroenterologist and a board-certified colorectal surgeon. I can't stress the importance of this enough. You need an expert when you're dealing with cancer.
Second, make sure you get genetic testing. There are a couple types of colon cancer that cause the body to form lots of polyps. One is called FAP (familial adenomatous polyposis) and another is called Lynch Syndrome. Lynch Syndrome is associated with an increased risk of colorectal cancer as well as other forms of cancer including endometrial, ovarian, gastric, urinary tract, and pancreatic. You need tests for MLH1, MSH2, APC, MSH6, PMS2, and MUTYH, so make sure you ask your oncologist for genetic testing for Lynch and other mutations. This is especially important in your case since you've already had breast cancer.
Are you seeing an oncologist? Or just your GI doc? Did they tell you the stage of the cancer? Did they do a CT scan to make sure there was no spread to other parts of your body? Did they do a CEA test? Ask for copies of your pathology report. That's where the staging information is located. See if you can get referred to a board-certified oncologist for his/her opinion on your treatment.
Since you had colon cancer and you also had precancerous polyps return in less than a year, I think your doc should be monitoring you more closely than waiting another 2 years for a colonoscopy. Get the genetic tests, a CT scan, a CEA test, etc. and then think about getting a second opinion on how you should be monitored. The good news is that your last colonoscopy found the polyps when they were just "precancerous." That's what should happen. However, in my opinion, your current doc is too cavalier with your monitoring by waiting so long for the next colonoscopy considering your history. Don't take chances with your life.
Hope this helps!
Stage IVb, liver/lung mets 8/4/2010
Xelox+Avastin 8/18/10 to 10/21/2011
LAR, liver resec, HAI pump 11/2011
Adjuvant Irinotecan + FUDR
Double lung surgery + ileo reversal 2/2012
Adjuvant FUDR + Xeloda
VATS rt. lung 12/2012 - benign granuloma!
VATS left lung 11/2013
NED 11/22/13 to 12/18/2019, CEA<1