I wasn't aware that Mammaprint offered anything other than High or Low. See:

https://www.agendia.com/our-tests/mammaprint

There is a contact link on that page that might be helpful but the best thing is to contact your MO's office.Good luck.

Or perhaps we was referring to the far end of the low risk scale? It doesn't sound as though he gave you a copy of your report, so that would be something to request a.s.a.p. just in the interest of having complete records of your dx. and treatment if nothing else.

I'm just reading over those links (Thanks Beesie!) and I'm wondering, since they are based on Post-Meno women (as far as I can see) what does that mean for those of us that had Mammprints but are Pre-Meno? Hmmm curious.

EDJ3 -- > I'm glad you were able to find the info you needed. I'm curious, did you also have the Oncotype run? Or did your MO tell you what your calculated risk of Recurrence/METs would be without therapy?

The only reason I ask, is that even though I am low risk via MP test and borderline with my Oncotype (it was my decision to forgo chemo), my actual risk factoring in age, blah blah blah is 28-35%, so for me any therapy that can cut it down to the teens or single digits is helpful. Anyway, just something else to factor into the puzzle if you haven't already.

Can I ask you ladies, what it means that this study is based on Post Menopausal women? Does that mean Mammaprint should not be used for PreMeno? I'm now confused...a little help?

ASCO Post https://ascopost.com/News/57839

"Study Details

In a previous study, the investigators identified a MammaPrint score threshold below which no breast cancer deaths in women with node-negative disease were observed at 15 years with no systemic therapy in a series of patients with 25-year follow-up.

The current analysis involved postmenopausal women with clinically detected node-negative tumors ≤ 3 cm randomized to receive tamoxifen vs no adjuvant therapy after mastectomy or lumpectomy and radiation who were enrolled in the Stockholm tamoxifen (STO-3) trial between 1976 and 1990 (ie, before the screening era). In the trial, patients received 2 years of tamoxifen or no systemic therapy regardless of hormone receptor status; those without relapse were eligible to reconsent to further randomization to 3 additional years of tamoxifen or no further treatment. MammaPrint risk scoring was performed using formalin-fixed paraffin-embedded primary tumor blocks. Risk thresholds for the 70-gene assay were ultralow (≥ 0.355), low but not ultralow (> 0, < 0.355), and high risk (< 0)."

Spoonie,

The screenshot you included in your post does say that Mammaprint was validated in studies that included pre-menopausal women. Here is the chart that lists those studies:

As for why the "ultra low risk" study was only done on post-menopausal women, I would guess it's because it's established that age is a factor that affects risk, and all other things being equal, older women have a lower risk. Therefore since this appears to have been a preliminary study to see if such a thing as an 'ultra low risk' cohort exists, it makes sense to start off by looking at the population group that is most likely to fall into that cohort. This doesn't mean that there might not also be pre-menopausal women who are ultra low risk, but this would have to be evaluated separately and I would guess that the score that puts someone into the ultra low risk category might be higher for pre-menopausal than it is for post-menopausal.

We see this with the Oncotype test, where there are different recurrence risk charts for those over age 50 versus those who are 50 or younger. This goes even further with the Oncotype RSPC (Recurrence Score Pathology Clinical) computer program, which some MOs use (mine does), that incorporates age, tumor size and tumor grade together with the Oncotype score, to come out with a more personalized recurrence risk. Age is a significant factor in this model. Although all over 50s are given the same recurrence risk based on their Oncotype score, using this model, at an Oncotype score of 35 (for example), someone who is 65 will have a lower risk of mets than someone who is 51, and someone who is 80 will have a lower risk still. I would assume the same is true for those who are younger, with someone who is 35 having a higher risk than someone who is 49, all other things being equal.

Thanks Beesie for the extra clarification, much appreciated and helpful. I think I kind of figured that out last night but didn't explain it very well.

What I came away with about the two tests, (sorry for being off topic EDJ3) is that like you said pre-menopausal women were used in both studies but there is a big difference in what they actually test/factor in to the rating and how it's possible (with Oncotype) that results could be different based on what time of the month a premeno patient has their biopsy and/or surgical removal of the cancer/tissue that will be tested.

According to https://www.frontiersin.org/articles/10.3389/fonc.2016.00241/full,

"Despite the known role of estrogen and progesterone on the function of the breast and on breast cancer risk, the effect of menstrual cycling on breast tumors remains unknown. In support of the possibility that menstrual cycle critically affects the gene-expression profile of breast cancers, a recent in vitro study has suggested that the combination of estrogen and progesterone results in the switching from a Luminal A to Basal-like intrinsic subtype in breast cancer cells, and increases the Oncotype DX Recurrence Score (43) compared to estrogen treatment alone. Tests that utilize gene expression profiling in breast cancer classification were developed and validated from studies predominantly in postmenopausal women, and there is a scarcity of research on how applicable these biomarkers are to premenopausal women, and the extent to which this impacts on treatment response. It is important to understand how hormonal fluctuations affect predictive and prognostic biomarkers, to provide premenopausal women with the optimal treatment for their individual cancer.

Conclusion

Breast cancer clinics are increasingly adopting gene expression profiling to subtype tumors and identify the best therapies. However, despite their availability to young women, such tests were largely developed and validated in postmenopausal women – patients in whom fluctuations in estrogen and progesterone associated with the menstrual cycle are absent. Yet, these hormones are highly likely to affect breast cancer gene expression in premenopausal women – and the diagnosis and treatment trajectories that stem from its measurement – could fundamentally depend on a patient's menstrual cycle stage at the time of tissue sampling. Leading diagnostic tests harness intrinsic subtyping of breast cancers, but whether these tests are accurate for premenopausal women remains a startlingly open question. Quite simply, young women may be at risk of receiving inaccurate subtype diagnoses; with ramifications spanning inaccurate prognoses, suboptimal and unnecessary treatments, and reduced survival."

My take away, which maybe I misunderstand, is that Oncotype DOES factor in ER PR readings etc into their genome testing/recurrence scoring, so if the sample is from a Pre-meno patient, some of those readings would fluctuate during the month based on their cycle and thereby possibly cause a misinterpretation. While it seems that the Mammaprint DOES NOT include those variable elements into their profile, so as that article states, therefore " It is likely that Mammaprint is appropriate for diagnosing BC in premenopausal women.". So again my interpretation - Mammaprint is likely to be more accurate for premeno women vs Oncotype. Interesting and something I'll be poking my Mos brain about at our next appt just to learn more.