Need a ONCO DX test but was started on letrozole before surgery

My understanding is that doctors order ONCOTYPE on pre surgical biopsy to determine if chemotherapy might be a useful pre surgical treatment to shrink tumors and treat lymph nodes in the hope of reducing the need for radical axillary node removal.

I've had the OncotypeDX and know a little about it. I don't know why your surgeon didn't automatically save tumor tissue, collected during surgery, as mine did automatically so genetic testing can be done. Unless as you mention the tissue sample would be too small? But the tumor removed from me was 5mm and sufficient for two biopsies and OncotypeDX test. I don't think that being on letrozole would have made the OncotypeDX invalid but could be wrong.

Oncotype has other breast cancer tests that might be helpful so you could call them and ask if there are options still available.

It would seem that you need to find an oncologist who's familiar with all of the genetic testing that might apply, including any that don't require tumor tissue samples. There are several companies testing for different things, including well-known mutations, and some can be identified with blood tests. And new tests being approved frequently. So, if your doctor(s) aren't fully aware of all of them, maybe they can refer you to someone with more knowledge who might be more helpful?

And, just maybe, one of the two facilities that did the biopsies has automatically saved tissue for further testing?

In any case, I'd get a second and maybe third opinion by consulting with at least one other oncologist if this is, as noted, an unusual cancer to deal with. There might be a few different treatment paths to consider and you'll want to be able to choose your best options.

I would call the Oncotype Dx folks and ask them about the effect of neo-adjuvant letrozole on test results obtained after surgery. The company is Genomic Health and they are very helpful.

I’m not sure what my two biopsies were called technically, procedure wise, but my two Oncotypes were based on the biopsies and I had results before surgery.

My experience was a needle biopsy followed by the injection of a clip to identify during mastectomy.

The order for the Oncotype DX must have been ordered to be done during your biopsy. Enough tissue would have taken the test at that time. This is the point at which I fell through the care net. Thank you and best wishes 🙂

Thank you so much for your reply and great suggestions. To clarify, I was told that taking the letrozole prior to biopsies would invalidate much of histological and genetic testing. Onco type testing was never brought up until after surgery. I was then told it wouldn't be accurate or have much meaning since the surgical pathology tissue was exposed to letrozole. All biopsy tissues and surgical tissues are saved for 10 years by the receiving labs. I am trying to find out if all the different types of testing an Oncotype DX does and see if any of them may be valid with the available tissue. My multiple biopsies with 2 different labs are "not enough tissue" for this test so I am told. My plan now: Awaiting ONCOTYPE DX company to contact me, 2nd opinion from another oncologist, I will contact both labs that hold my biopsy tissues, determine how much each have and if combining them may be enough for part or all of the ONCOTYPE DX testing. Again, I appreciate your interest and time put into this.

I just spoke with a customer service representative at Oncotype and he didn't know if the letrozole would rule out the OncotypeDX test. And my 'science guy' contact there was off today. I'll try to get an answer tomorrow as I have a few questions of my own. [I want to find out if I can get the exact lab results from my test not just the 'final results which was, thankfully, very good.]

Wow, I don't know how to thank you Callallo. I would be most grateful for any information you receive. I am a few weeks post-surgery and still recovering with pain, emotional stress and fatigue. I am finding all of this overwhelming. I have my loved ones encouraging me to let this go. I do not think they understand the importance of this for my future.

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.]