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.