Numbers Associated with HER-2 Positivity

Could someone please help me understand the numbers I keep reading here related to HER-2 positivity? I think I've read things like "HER-2, 9.6" or "HER2+++" and so on.

I assume the +++ must be the IHC scale, where 1 is negative, 2 questionable and 3 positive. But I thought I saw one HER-2++++.

The FISH part of my path report reads:
"nuc ish 17q11.2-q12 (HER-2 amp+). The ratio of HER-2 to CEP17 is greater than 4.0."

I have forgotten to ask the docs for over a year, so I hope someone can explain or perhaps direct me somewhere I can get this information.

Tuesday

I found this article which explains FISH and IHC test results.

HER2 Testing


Warmest Regards
Joe

That is comprehensive, straightforward, up to date info that even I can understand, Joe. I appreciate it so much.

AlaskaAngel

Joe's site explained IHC and FISH nicely, but I didn't see anything addressing the question about numbers. IHC is reported as 1-3 plusses, or +++'s. FISH is negative or positive, but in the fine print, at least for some of us, there's also a HER2/CEP 17 ratio. A ratio of >2 is positive, but some of us have values considerably higher than that, and I too would like to see information that discusses the significance of the ratio number, both as it applies to prognosis and to response to Herceptin. Has anyone found anything about that?

Debbie Laxague

Debbie,
I could not locate any information about the significance of being greater than 2. You may want to contact Dakocytomation who developed the FISH test.

DAKO Cytomation Home Page

Warmest Regards
Joe

I've been reading, but can't find specific information as to what a higher ratio of HER-2 to CEP 17 suggests in terms of treatment or prognosis. I can only assume that a higher percentage of Her-2 markers--and I do know that the test actually turns parts of the cell nucleus orange or green and that reading the test is a matter of counting how many orange or green spots there are--would indicate a the possibility of better response to Herceptin. Of course that is an assumption, so take it for what it's worth. I plan to ask my onc today, and I'll get back with what I learn.

My kids used to tell me I was nuts because I'd spend months learning about some oddball thing or another just for the heck of it. I may never need to know how an offshore oil platform works, but all that scratching of my head over genetics is finally coming in handy. <g>

Tuesday