chemo for small tumors

[loulou55]

I am a 54 year old woman diagnosed with IDC and Ductal carcinoma in Situ after a wide incisional lumpectomy.  the path report reads: Tumor consists mostly of DCIS.  Intermixed however is a 0.2 cm focus of IDC. The IDC is grade II. It is a single focus. no necrosis, no lymphatic invasion, no venous invasion.  The In Situ component is grade III comedo type, and is 0.5 cm. There was no extensive intraductal component.  MY closest margins were 0.3 for the IDC and 0.3 for the DCIS as well.  Other margins were much larger.  Sentinel node negative .  It was ER and PR negative.  And HER2 neu positive.  I'm Planning to start radiation treatment soon, but understand the chemo would come first if at all.  MY doctors feel it is not needed due to the size of the tumor and clean margins.  I would be followed with MRIs and mammograms.  Do you think this is a reasonable plan?

[katarina777]

I don't know if this is any useful advice but it just occurred to me after Bluebutterfly 222 sent me an article about these tests not always being accurate, like in 10% of the case?

My initial testing also said HER neutral-positive, and then my oncologist sent a sample to a lab in Seattle who did something called a FISH test? It came out negative.

I just think in your case a second opinion may be worth it?

KAT

[SueYoung55]

Her2 NEU positive and no chemo? I don't think that is a reasonable plan. See some information below from Wikipedia. Please have a conversation with your Doctors about this. The first diagnosis and treatment for breast cancer is the most important, in my honest opinion. Please please research this before making a decision in your treatment. Please. And best wishes to you and your family. This isn't an easy road but you can do it. :)

HER2/neu (also known as ErbB-2) stands for "Human Epidermal growth factor Receptor 2" and is a protein giving higher aggressiveness in breast cancers. It is a member of the ErbB protein family, more commonly known as the epidermal growth factor receptor family. HER2/neu has also been designated as CD340 (cluster of differentiation 340) and p185. It is encoded by the ERBB2 gene.

Approximately 15-20 percent of breast cancers have an amplification of the HER2/neu gene or overexpression of its protein product.

Overexpression of this receptor in breast cancer is associated with increased disease recurrence and worse prognosis.

Because of its prognostic role as well as its ability to predict response to trastuzumab (Herceptin US brand name) (see below), breast tumors are routinely checked for overexpression of HER2/neu. Overexpression also occurs in other cancer such as ovarian cancer, stomach cancer, and biologically aggressive forms of uterine cancer, such as uterine serous endometrial carcinoma.

Clinically, HER2/neu is important as the target of the monoclonal antibody trastuzumab (marketed as Herceptin). Trastuzumab is only effective in breast cancer where the HER2/neu receptor is overexpressed. One of the mechanisms of how traztuzumab works after it binds to HER2 is by increasing p27, a protein that halts cell proliferation.

The expression of HER2/ERBB2 protein is regulated by estrogen receptors. Furthermore estradiol and tamoxifen acting through the estrogen receptor normally down regulates the expression of HER2/ERBB2. However when the ratio of the coactivator AIB-3 exceeds that of the corepressor PAX2, the expression of HER2/ERBB2 is upregulated in the presence of tamoxifen leading to tamoxifen resistant breast cancer

Overexpression of the HER2 gene can be suppressed by the amplification of other genes and the use of the drug Herceptin. Research is currently being conducted to discover which disregulated genes may have this desired effect. Another monoclonal antibody, Pertuzumab [3], which inhibits dimerization of HER2 and HER3 receptors, is in advanced clinical trials.


The oncogene neu is so-named because it was derived from a rodent glioblastoma cell line, which is a type of neural tumor, hence 'neu.' HER2 is named because it has a similar structure to human epidermal growth factor receptor, or HER1. ErbB2 was named for its similarity to ErbB (avian erythroblastosis oncogene B), the oncogene later found to code for EGFR. Gene cloning showed that neu, HER2, and ErbB2 were the same.

HER2 is co-localized, and thus most of the time co-amplified with the gene GRB7, which is also a proto-oncogene (active in e.g. breast cancer, testicular germ cell tumor, gastric cancer, and esophageal cancer).