I found the answer to my question online, so I deleted the question part of it. But I will leave the information below in case anybody wants to weigh in - so to speak.
I'll tell you a bit of a scary catch-22. I am about 40 pounds overweight. One thing they tell breast cancer patients, especially estrogen-positive bc patients, is to stay at an ideal weight in order to avoid recurrrences. Well in the medical questions for the IP diet, they say that "theoretically any cancer cells still present could get stimulated by the estrogen released" as one loses fat. So they tell us to lose weight to help prevent recurrences, and then I read that estrogen release from fat loss can stimulate any cells still present.
I need to lose the weight, so that's what I'm going to do.