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Need a ONCO DX test but was started on letrozole before surgery
Breast Cancer | Last Active: Dec 14, 2023 | Replies (33)Comment receiving replies
Hi Randy,
OK here's what I learned from talking to the Oncotype people (at Exact Sciences) today including the person I think of as 'the science guy because he's the person physicians call but helped me a lot when I was trying to understand what the OncotypeDX tested and its algorithm when I had a lumpectomy last October.
The OncotypeDX would be invalid if the client had already had aromatase inhibitors, radiation or chemo. So the letrazole would preclude valid results from an OncotypeDX test.
BUT, they do accept tissue for analysis from biopsies with the following caveats and maybe this gives you an option. The rep did note that some insurance companies won't cover biopsy genomic testing but that's a different issue.
1. The sample must be at least 2mm of 'continuous' tumor tissue. (Basically at least a 2mm clump of tumor tissue.)
2. The cancer must be estrogen positive. (It can be progesterone negative and, though you didn't mention HER2 status, they accept both HER2 positive and negative. [The most common tissue they receive though is from E+, P+, HER2- tumors.]
Also someone elsewhere on MC posted that the "risk of recurrence" number clients receive from an OncotypeDX test precludes the risk of spread from the original tumor. That is incorrect. The 'risk of recurrence within 9 years' applies to "anywhere in the body." But I think there's an assumption that surgery left clean margins. Some tissue submitted to Oncotype is rejected or sent back because misdiagnosed. Including samples from tumors labeled non-invasive which clearly show signs of invasive characteristics in the labs at Oncotype.
My OncotypeDX risk result was 3% (if I took aromatase inhibitors). Which translates to approx. 5.5% risk if I don't. I didn't have radiation. And the low OncotypeDX number ruled out chemo. So the test was very important in my decision(s). I post about these genomic tests so others can nudge their doctors into being conversant with the array and quality differentials of the tests available. Data is data and is all that we have to work with other than physicians' experience and our own knowledge and gut instinct about our own bodies.
I hope this is helpful for you and anyone else able to get this test done if they know about it aforehand.]
Replies to "Hi Randy, OK here's what I learned from talking to the Oncotype people (at Exact Sciences)..."
Thank you so much for the information. Your summation of the issue is well stated. The information you provided was my understanding but without some of the details. I am HER2 negative. The one thing I didn't know is the necessity for a 2mm piece of continuous tissue, which is why the one lab is telling my doctors there wasn't enough tissue to perform the test prior to aromatase inhibition therapy. I think I need to double-check that both labs evaluate two different sets of biopsies on 5 tumours total. I started on letrozole after both biopsies and 5 weeks prior to surgery for a double mastectomy and lymph dissection. All 4 lymph nodes were negative 🙂 It is unclear whether the doctors understood they were done at different facilities/labs. It also sounds like a specific order needs to be in place to ensure a large enough sample is biopsied for the purpose of this important test.
It seems I have no options regarding getting this test done in some form. I will not accept my Oncologist's plan to wait until possible metastasis. I plan to get 2nd and 3rd oncologist opinions if necessary. My other goal is to share this so as to prevent others from this catch-22. Although I am not looking to finger point and will not, I think the companies' reps doing the ONCOTYPE DX need to educate the surgical and medical oncologist as well as the doctors ordering the initial biopsy such as the obstetrician/gynaecologist. The latest studies are showing promising data on starting endocrine therapy prior to surgery in certain cases. Doctors need to understand these timing issues. I'm concerned and sad I may need to move forward without a clear prognosis, not what I expected. I thank you for your time and interest in this subject. I promise to post any further information I find. Wishing you all well on your BC journeys. Hugs, Randy
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Incredible information. Thank you for taking that step. I obviously had enough biopsy tissues (2 tumors) to get an ONCOTYPE pre surgery as the oncologist would have begun chemo before surgery to reduce excessive surgical harm to axillary nodes ( shrinking or clearing).
For a 3% recurrence risk with AI … what would an Oncotyoe score look like?