Lani

From reading the serum her2 literature in general and from comments by Walt Carney who invented and developed the test, its value has only been officially "validated" in metastatic patients and they are unsure of its meaning at all in premetastatic patients.
In those readings, I found the article I quoted above which, when read in its entirety, discusses premetastatic patients following chemo (which causes marked reduction of estrogen) or injection of leuprorelin (which causes a hormonally induced temporary "castration") caused serum her2 to increase markedly. It discussed the fact that her2 positivity in the primary tumor depends on which phase of the menstrual cycle it was removed during ie, the amount of estrogen influences the degree of her2 positivity. Similarly other articles I have read reveal the Ki67 level varies with phase of the menstrual cycle which coincided with the surgery. This full article discusses that as well and points out it has implications when deciding on treatment based on these values, which merely reflect a snapshot in time of a changing beast.

In this article they could not correlate increases in serum her2 neu in premetastatic patients with them subsequently developing mets, but the serum her2neu literature listed on the BayerOncogene website cites the article you previously brought to my attentiion on the lag time between serum her2 increase and mets.

Are you on antiestrogen therapy, particularly aromatase inhibitors--these lower your estrogen and thereby may increase your serum her2neu according to this article? Have you had your ovaries removed during/before your serum her2 went up? How long has it been since your chemo--are you post-menopausal? Are you on Herceptin --a decrease of 23% or more within 3 weeks of initiation of Herceptin treatment is felt to reflect efficacy of Herceptin IN METASTATIC PATIENTS ONLY EVEN IF THEIR BASELINE SERUM HER2 WAS <15.

Walt Carney did not think there was any indication that an increase in serum her 2 OF ANY VALUE <15 was anything to worry about in a premetastatic patient--that the knowledge of its values and fluctuations in premetastatic patients just isn't there yet.

I have previously discussed different labs doing the test.

Be certain to read your report as to where it was done and with what technique. When Specialty labs machine went down they farmed the test out to another lab, where results came back higher and the normal range was different. My one dealing with Lab Corp had the result come back 50% over the previous result--ARUP uses a manual rather than automated version of the test, but 3 weeks later it was back to the pre 50% increase level (but they have a slightly different normal range at 13.5%)

Gina is a master at titrating(finely adjusting) her treatment based on her serum her2 level , but then again, she is metastatic.

Beware, many of the labs print out on the results that the test is only approved/validated in the metastatic setting. LET'S HOPE THE INSURANCE COMPANIES DON'T LOOK AT THAT TOO CLOSELY or we will never have the results we need to find out if it is an accurate marker of tumor progression/response to treatment