20% estrogen pos Her-2 pos Should I continue AI past 5 years

What does your MO recommend? I've told myself that even if it's recommended to me to continue past five years, I'm going to take a nice long break and see what life is like without it.

I was 11-25% estrogen positive and felt very comfortable quiting after 5 years.

I was Her2+ and did the Breast Cancer Index test at the five year point. BCI gives two results, a figure that predicts recurrence risk, and one that gives an estimate of benefit from continuing anti-hormonal drugs. There are multiple arrangements - high risk of recurrence and high benefit of continuing the drug, low risk of recurrence and low benefit, low risk of recurrence and high benefit, and the dreaded high risk of recurrence with low benefit. I was the last one... but my question for my oncologist was whether or not the high risk of recurrence was due to the Her2+ aspect since they are testing your original tumor material. His short answer was I don't know, and neither does the Biotheranostics rep, since they had discussed this. The test doesn't necessarily suss out that detail. I did request, and receive, a PET scan at that point because I felt that I was likely not receiving a great deal of benefit from anti-hormonals all along and wanted a snapshot of where I stood at the five year point. I had previous PET scans that had normal results, but this was my first abnormal one - bilaterally across the chest. Scary moment - and I was actually already scheduled for surgery with my PS the following week, so she did a bunch of biopsies with direction from my BS while she was in there. I had four different types of inflammatory process and a big (3cm) suture granuloma from my original BMX, but no cancer thank goodness. Another question for you specifically - since they do test the original tumor material - is whether you can you even have the test since the tumor material - if there was any - has been affected by neoadjuvent chemo and targeted therapy? FWIW, my oncologist did recommend continuing on letrozole since I was doing ok on it, and because I was high risk, and because low benefit is not necessarily zero benefit. I went another two and a half years, then discontinued because I needed some pretty invasive dental work done and the maxillofacial surgeon wanted me off all meds. It seemed like a good time to stop, and my oncologist agreed.

I have now completed seven years of taking letrozole and have had minimal side effects. In fact, after changing my way of eating to high fat, low carbohydrate three years ago, I have dropped over 40 pounds from my highest weight. I am severely insulin resistant but due to my weight loss have been taken off a diabetic drug that I was on for years. I plan to ask my oncologist if I can continue on letrozole for a total of ten years. I have noticed hair thinning but that is most likely due to my age. I have been a walker for over fifteen years as well and I think that it helps to keep my bones strong. I am just grateful to still be here enjoying life with my sweet husband.

I have talked with the folks at Breast Cancer Index and the result on benefit of extended endocrine therapy is "binary" so it is either yes or now. It is not a spectrum of low to high.

They have changed the terminology for risk of recurrence. My 5.7% risk was labelled "high" at BCI (cut off was at 4.8) but was termed "low" with Oncotype. They realize that perception of risk is subjective and some people are only happy with 2%, say, and some are fine with 8%.

I also had the Prosigna Assay at the 5 year point and that test had me at almost 10% (moderate) risk.

These test results can be all over the place, and each test has different standards for low and high and medium.

But main message with BCI is that either you benefit or don't from extended hormonal meds. It is not "low" but "no."

They cannot answer whether that means these meds NEVER benefited us, but it seems likely. I had 95% ER and 80% PR. One would think hormonal meds would be very beneficial, and Oncotype said it halved my risk to 6%.

The BCO folks said that the pathology results for hormonal responsiveness are like counting the cars on the highway and the BCI is like measuring how fast they are going.

Am I comfy with not taking them longer? No. I am taking a break to deal with my bones and still hope to do another two years.