Oh gosh, @mak70. It's obvious from your quick succession of posts that you are frustrated, mad and probably scared. The waiting game is excrutiating. I really don't think they are stringing you along, but it does sound like things are not being explained well enough for you to have confidence in the care you are getting.

Rectal cancer grows very slowly. They likely want to take another and better biopsy sample to get an exact reading on the cell markers and what they are dealing with. For example tumor size, composition, vascular involvement or not, etc. This will help decide the best course of treatment and improve the outcome of treatment.

You can continue to call Mayo Clinic for an appointment, but who has time to wait on hold? Instead you can fill out the online form and tell them what time to call you. Let them know when you'll be available. Here's a link to the online form: http://mayocl.in/1mtmR63

It's not time to lose hope. It's time to get clearer answers. Are you able to call the surgeon's office to get a better understanding of why another biopsy is needed?