How did you decide on breast cancer treatment based on Oncotype?

We did meet with the oncologist who reviewed fully every item on my pathology report. We discussed the all clear with a bilateral mastectomy and low possibility of recurrence and additional treatment. She did not think letrozole prior to surgery would affect the results. With a mid-range score of 28, we decided that chemo was not an option at my age. She ordered a mammaprint test to get more clarification but we are still waiting for the results. Because I will be more than 120 days from diagnosis, chemo benefits may be reduced anyway. That’s a consideration for anyone who is delayed for treatment. The process is now in place with mastectomy completed and an AI for 5 years with regular monitoring. We hope that is a good ending to my health story.

So here I am trying to make a decision regarding chemo treatment after an oncology meeting next week. The facts are single mastectomy for invasive carcinoma no specific type, grade 1 stage 1 ER PR positive, Her 2 negative, clean nodes and margins following surgery. I started on letrozole 2 months prior due to delays in scheduling and continue with minimal side effects. The Oncotype score of 28 is intermediate and surprised the oncologist. Does letrozole prior to surgery affect the Oncotype score? At 75, I am reluctant to have chemo when I consider all the positive results of my cancer. What to do now?

I had IDC a grade 1, stage 1, 8mm tumor size and no lymph node involvement and my Oncotype came back as a 29 which also surprised us. Since it was so unexpected and was the outlier, I paid to have the Mammaprint test just to see what that test would show. It came back as low risk or recurrence. Then I find out after all of this two years later that I should have never had the Oncotype test because my tumor characteristics where never part of the TailorX trial which is the research study that is often referred to for the Oncotype. I did not do chemo after consults with 10 oncologists.

@vegada the TailorX trial was intended to determine whether patients with intermediate Oncotype scores (11-25) did as well with hormonal therapy alone, or with chemo as well.

It would seem the reason your tumor "characteristics were never part of the TailorX trial" is that your score was higher than 25. However with grade 1 and small size, the decision to forego chemo might be supported by many docs. I am glad the Mammaprint had a better score and that your doc is relying on that.

The TailorX trial was not relevant for scores outside that range, since most with scores 0-11 were doing hormonal therapy only and most with scores over 25 were doing chemo. The Oncotype was being well before the Tailor X and the Tailor X was supposed to clarify things for those who were in that gray area of intermediate. Your situation, with low grade and small size, and score close to 25, might be seen- and was seen- differently.

I had discordance in tests as well. I had grade 3, LVI, high ki67% but low Oncotype at 8. After 5 years on letrozole, I also had a Breast Cancer Index and Prosigna Assay done and my scores were higher risk.
I am 8 years out from diagnosis.

I also had a positive HER2 test, two equivocals and two negatives (borderline) but no chemo or meds for HER2.

It is disturbing to feel we cannot rely 100% on testing but we all do the best we can. I admire you for seeing 10 oncologists. I saw 4! 🙂 Good luck!
https://www.nih.gov/news-events/news-releases/tailorx-trial-finds-most-women-early-breast-cancer-do-not-benefit-chemotherapy

I agree that it is very disturbing that we can't rely 100% on testing. What I am saying is that they don't recommend people with my tumor get the Oncotype test done because the tumor size that was studied started at 1cm and mine was 8mm. T1bN0 Cancer stage was not part of the Tailor X and so most doctors don't order the Oncotype or shall I say it has been published that doctors should not order an Oncotype for T1bN0.

I agree that it is very disturbing that we can't rely 100% on testing. What I am saying is that they don't recommend people with my tumor get the Oncotype test done because the tumor size that was studied started at 1cm and mine was 8mm. T1bN0 Cancer stage was not part of the Tailor X and so most doctors don't order the Oncotype or shall I say it has been published that doctors should not order an Oncotype for T1bN0.