Two types of her2 tumors

[Nancy L]

I found the last paragraph most interesting. Maybe this helps explain why some respond to the Her2 drugs and some don't. If this is the case and identified before women are put into trials for her2 drugs, it should dramatically affect the trial results and speed up approval process.


Breast cancer genome analysis highlights 4 subtypes, link to ovarian cancer Full Text
OBG Management, 11/09/2012 Clinical Article

Yates J.– According to a study published in the journal Nature, analyses from the Cancer Genome Atlas (TCGA) have confirmed the existence of four primary subtypes of breast cancer, each with its own biology and survival outlooks. The standard molecular subtypes are:luminal A tumors,luminal B tumors, basal–like cancer, also known as triple–negative breast cancer because most of these tumors test negative for three receptors: estrogen, progesterone, and human epidermal growth factor receptor 2 (HER2), HER2–enriched tumors.In their analyses, funded by the National Cancer Institute (NCI) and the National Human Genome Research Institute (NHGRI), both part of the National Institutes of Health (NIH), researchers described new insights into the four subtypes based on a comprehensive characterization of samples from 825 breast cancer patients.

The standard molecular subtypes are: luminal A tumors, luminal B tumors, basal–like cancer, also known as triple–negative breast cancer because most of these tumors test negative for three receptors: estrogen, progesterone, and human epidermal growth factor receptor 2 (HER2), HER2–enriched tumors. In their analyses, funded by the National Cancer Institute (NCI) and the National Human Genome Research Institute (NHGRI), both part of the National Institutes of Health (NIH), researchers described new insights into the four subtypes based on a comprehensive characterization of samples from 825 breast cancer patients.

Most breast Ca cases involve luminal tumors. The milk ducts of the human breast, lined with luminal cells, are the most common origin of breast cancers. Malignancies that arise from these cells are fed by estrogen, spurring growth. Treatment for luminal cancers is fairly uniform, with good outcomes for many patients, though some respond poorly. Therefore, luminal cancers are divided into type A (responsive to treatment) and type B (not as responsive).
Triple–negative breast cancers linked to serous ovarian cancer. One of the most dramatic discoveries of this analysis was the marked genomic similarities between the basal–like subtype and serous ovarian cancer. The mutation spectrum—or types and frequencies of genomic mutations—were largely the same in both cancer types. Further analyses identified several additional common genomic features, such as gene–mutation frequency, suggesting that diverse genomic aberrations can converge into a limited number of cancer subtypes
Two types of HER2–positive tumors were identified.When researchers analyzed the genomic findings from tumors determined to be HER2–positive by standard cellular tests, they found that only half of the samples were actually HER2–enriched. The other half were characterized as luminal subtypes, suggesting that there are at least two types of clinically defined HER2–positive tumors.

[Mandamoo]

Nancy - I find all of the very confusing! Do you think this then means the Her2 luminals are the Hormone positives? and the other's are hormone negative? I have had some initial genomic testing on my tumors and it still finds that they are Her2 positive though hormone negative - I respond poorly to Herceptin and the only other mutation so far is a p53 mutation.
I think it underlies that all of our tumors are different with similar characteristics that can be targeted. I don't think the above finding necessarily explains resistance to Herceptin but it is an overwhelmingly complex area that I don't come close to understanding!

[Ellie F]

Really interesting. I suspect there are more than two but we have yet to identify them.
I also find it a bit confusing especially since the luminal type seems to be hormone driven. I wonder if this group should also respond to anti oestrogen therapy as well as herceptin to promote a good outcome?
Hope Lani or someone could clarify?

Ellie

[mamacze]

Nancy, thank you so much for posting this and thank you for your helpful editing. I just read the same article, then logged on and saw your post. I think this is wonderful news; the more the researchers are able to subtype our cancers, the better the nontoxic targets when they treat it. I say WHOO HOO!
Ellie great question about her2 and luminal type cancer. Also, Amanda, I am interested in your genetic mutation. What does the ve in your dx mean?
Kim (from CT)

[Mandamoo]

Kim - the ve in my signature is (-ve) negative - I am hormone negative. I am still awaiting further testing on my lung tissue - my initial testing was on my breast and lymph sample - showed I was Her2positive and other significant mutation was a P53 mutation - which occurred less frequently in my breast but increased to 53% in my lymph. We struggled getting lung tissue but were successful earlier this year and this testing is not routinely available in Australia and mine is being done through one of the universities here which has had trouble with funding so my data has been stalled - I believe it is on the go again so I am hoping for more news soon.
This is a fascinating field and I hope they come up with more soon.

Also, I have been on everolimus/affinator (we thinks so - it was a blind trial) - if you want to know more happy to tell you my experiences but it did help to keep me stable for 7 months.