Oncotype DX Test: What does it all mean?

@psd8 @montie @1231 @dawn88, welcome to Connect.
The Oncotype DX tool has been helpful in sparing women with early stage breast cancer from having additional treatment when risk of recurrence is very low. For women whose scores are in the mid or intermediate risk range, the choice to have chemo and/or radiation remains tough. I find this explanation of the test and decision-making helpful. https://www.breastcancer.org/symptoms/testing/types/oncotype_dx

Dawn and 1231 - how are you managing on chemo?
Psd8 - what type of chemo is being suggested?

My wife was diagnosed with a ductal carcinoma last August, with 2 lymph nodes involved. She is ER+, HER2- and carries BRCA1 gene. She had a bilateral mastectomy, followed by 6 chemo cycles 4 weeks apart. She also had the Agendia genetic test carried out on tumour tissue which places her in the 'high risk' of cancer returning. How does that test compare to DX please?

She is now taking Tamoxifen and at 45 can't live with the side effects and is now determined to stop taking it. I thought she would benefit from a PARP inhibitor (Olaparib) but she does not meet the requirements (1 less lymph node involved than required). However, looking at the statistics for those with bilateral mastectomy, it appears that Tamoxifen only provides roughly 1.35% additional reduction in risk - the main benefit being for those who have had a lumpectomy or single mastectomy. 10 years of Tamoxifen, with the noticeable and potential long term side effects for a 1.35% benefit in risk reduction does not seem to be of real benefit given the overall effect on quality of life. Is it the case then that she is right to want to discontinue this treatment, and rely on annual checks instead, her decision is worrying me more than it is her?

My wife was diagnosed with a ductal carcinoma last August, with 2 lymph nodes involved. She is ER+, HER2- and carries BRCA1 gene. She had a bilateral mastectomy, followed by 6 chemo cycles 4 weeks apart. She also had the Agendia genetic test carried out on tumour tissue which places her in the 'high risk' of cancer returning. How does that test compare to DX please?

She is now taking Tamoxifen and at 45 can't live with the side effects and is now determined to stop taking it. I thought she would benefit from a PARP inhibitor (Olaparib) but she does not meet the requirements (1 less lymph node involved than required). However, looking at the statistics for those with bilateral mastectomy, it appears that Tamoxifen only provides roughly 1.35% additional reduction in risk - the main benefit being for those who have had a lumpectomy or single mastectomy. 10 years of Tamoxifen, with the noticeable and potential long term side effects for a 1.35% benefit in risk reduction does not seem to be of real benefit given the overall effect on quality of life. Is it the case then that she is right to want to discontinue this treatment, and rely on annual checks instead, her decision is worrying me more than it is her?

@johndalton did your wife have the Oncotype DX or other genomic test like Mammaprint? These are different from genetic tests. The Oncotype report tells us that risk is cut in half by taking tamoxifen (aromatase inhibitors were not used when this test was first in practice so that my risk went from 12% to 6%. Where did you get the 1,35% figure (what is your source)?

On what basis was chemo prescribed? Were her estrogen and progeesterone scores low? Did she have a lot of positive lymph nodes? (The Oncotype is still done for up to 3 positive nodes.

If she did not have the Oncotype DX, she can still have it- the specimens are in storage and can be sent to Exact Sciences, the company that does the test.

I did 5 years of an aromatase inhibitor after doing another test called the Breast Cancer Index, which told me both risk and whether continued hormonal therapy was beneficial. I came out high risk (5.7%) but no benefit from extending the meds so I stopped. Your wife might be able to do 5 years. I have read that 7 is as good as 10 and wanted to do that but after the test, I stopped.

With a double mastectomy, I got checked for 5 years with a manual exam but after that no checks and no oncology appointments, even though risk continues to go up with hormonal cancers. Your wife might benefit from knowing that it isn't all that easy to check over time.

Any reason she is not coming on this forum herself?

Many thanks for your reply. My wife had the Mammaprint genetic test by Agendia, it places her in the 'high risk' of recurrence group, with a risk factor of 21%. The 21% was the basis of her having chemo. But again after double mastectomy I am unsure there would be a significant benefit from chemo. The problem is Oncologists seem very rigid in following the approved standardised regimen, and are not really open to discussion about it (we tried 4, in 3 countries and every time it was like banging your head against the wall)
However, she has had a bilateral mastectomy. Cancercentre.com and others confirm that:
"double mastectomy lowers the risk (of the cancer returning) by at least 90%.
If you have a disease-causing mutation in the BRCA1 or BRCA2 genes, the risk reduction is about 95% (my wife has BRCA1)
So this represents a 95% risk reduction of the remaining 21% had she opted for lumpectomy (a 1.05% risk of cancer returning overall). Even ignoring this and working on the remaining 5% risk after double mastectomy, the 12% reduction in risk on the 5% is actually just 0.6%. This however is just math, there do not appear to be any studies on those who have had double mastectomy and the additional risk reductions provided - at least I have not been able to find any (not for want of trying). All I can find simply says something along the lines of 'double mastectomy cannot guarantee that all breast tissue cells are removed, so patients should still follow a course of Tamoxifen'.
I appreciate it is not all that easy to check over time, but the real question is long term quality of life vs overall benefit to life expectancy with the tamoxifen. An additional consideration is the rapidity of development of new treatments and new testing capabilities. She will have an annual MRi or PET scan and blood tests, which combined should offer quite a good standard of monitoring, at least until she is beyond her menopause.
Throughout her treatment she has asked me to do the research, find answers, and question what medical professionals have told her. She has instead preferred to focus on recovery and wellness, and I have to say I find the way she has dealt with it and recovered truly remarkable. She puts it down to mindset and having not had to dwell on the disease and treatment. I did however end up having a complete breakdown towards the end of it, so perhaps I took some degree of the burden from her and shouldered more than I could cope with.

Many thanks for your reply. My wife had the Mammaprint genetic test by Agendia, it places her in the 'high risk' of recurrence group, with a risk factor of 21%. The 21% was the basis of her having chemo. But again after double mastectomy I am unsure there would be a significant benefit from chemo. The problem is Oncologists seem very rigid in following the approved standardised regimen, and are not really open to discussion about it (we tried 4, in 3 countries and every time it was like banging your head against the wall)
However, she has had a bilateral mastectomy. Cancercentre.com and others confirm that:
"double mastectomy lowers the risk (of the cancer returning) by at least 90%.
If you have a disease-causing mutation in the BRCA1 or BRCA2 genes, the risk reduction is about 95% (my wife has BRCA1)
So this represents a 95% risk reduction of the remaining 21% had she opted for lumpectomy (a 1.05% risk of cancer returning overall). Even ignoring this and working on the remaining 5% risk after double mastectomy, the 12% reduction in risk on the 5% is actually just 0.6%. This however is just math, there do not appear to be any studies on those who have had double mastectomy and the additional risk reductions provided - at least I have not been able to find any (not for want of trying). All I can find simply says something along the lines of 'double mastectomy cannot guarantee that all breast tissue cells are removed, so patients should still follow a course of Tamoxifen'.
I appreciate it is not all that easy to check over time, but the real question is long term quality of life vs overall benefit to life expectancy with the tamoxifen. An additional consideration is the rapidity of development of new treatments and new testing capabilities. She will have an annual MRi or PET scan and blood tests, which combined should offer quite a good standard of monitoring, at least until she is beyond her menopause.
Throughout her treatment she has asked me to do the research, find answers, and question what medical professionals have told her. She has instead preferred to focus on recovery and wellness, and I have to say I find the way she has dealt with it and recovered truly remarkable. She puts it down to mindset and having not had to dwell on the disease and treatment. I did however end up having a complete breakdown towards the end of it, so perhaps I took some degree of the burden from her and shouldered more than I could cope with.