What is "tumor marker"?

hlya

Hi, Ladies,

I saw people talking about "tumor marker", what does that mean?  Thanks.

sewmanythings

If I am correct it is the level of cancer cell in the blood... but as one of the ladies posted and I only read yesterday is that when you start chemo tumor markers go up as the cancer cell dies they are dispersed into the blood system which the bllod test see as cancer cell.... this was so encouraging..she also said we must not get hook up on markers and worry about them as during chemo they go up and down... I have battled in the past to find out a lot aboyt this on the web.. so find this yesterday was wonderful...

amlg1

I had an MRI biopsy and they put a titanium clip at the spot of my mass,I thought this is called a tumor marker..So DR.knows in the future the exact spot .since I have no palpable lumps.Now I am confused!

Gitane

Oncologists sometimes do tests on blood samples to measure "tumor markers".  They are using monoclonal antibodies to measure proteins (antigens) given off by the MUC1 gene I believe. I think this gene is associated with immune response and the protein is found on/in many different types of breast cancer cells.  Some of the tumor markers used in breast cancer are CA 15-3, CA27.29, and CEA.  Over time (months), if one or more of these marker measurements goes up repeatedly, it may indicate that breast cancer has spread to other parts of the body.  If this happens it could be 1 to 9 months before any cancer symptoms or measurable cancer is found.  It does, however, let the oncologist start tests/scans a little earlier than they might have otherwise.  In metastatic breast cancer it is used to measure response to treatment.  In early breast cancer the use of tumor markers is controversial.  Many oncologists don't measure this.  I have read it is reliable in about 66% of patients.  I have also read many posters here at bc.org saying the tumor markers aren't reliable for them.