Question about EGFR Expression

[pewjumper]

So, I can't seem to piece this together. Does EGFR expression affect prognosis? I know that EGFR positive tumors respond to drugs like Tarceva, but does being positive or negative have any bearing on prognosis?

And how does this relate to tumor grade? I saw on Dr. West's website that well-differentiated tumors seemed to fare better. Is an EGFR positive tumor well-differentiated? I don't get it.

[Andrea]

I do not have much to add at all except to say that I know my mom's tumor was tested for it a couple of years ago. I was told it had to do with helping decide what kind of treatment, etc, and not to read much into it.

I know that certain types of LC respond better to chemo. My mom's was a very high grade and we were told that responds better to chemo, whereas my dad's bronchoavelor carcinoma responds better to Tarceva than chemo.

That's my limited knowledge until you get more responses

[mary colleen]

Mitchell, as far as I know, grade (degree of differentiation) and EGFR expression are 2 independent factors. I believe that EGFR expression (or lack thereof) is part of the "genetic signature" factors that there is so much recent literature on. Has it been determined yet if your Mom's tumor is EGFR positive?

[pewjumper]

Mary Colleen,

Mom's tumor came back EGFR Negative so she's not a candidate for the Tarceva trial. I didn't know how to feel about that since I didn't know exactly how EGFR worked. Here is Dr. West's response to my question:

EGFR expression isn't related directly to grade - it's not measuring the same thing. EGFR expression is just an independent factor. Overall, there is some evidence that tumors expressing EGFR appear to have a modestly worse survival than tumors that don't express EGFR. There's also some pretty weak evidence that tarceva works better on tumors that have EGFR expression (have the protein EGFR on them). The work on EGFR positivity or negativity is still pretty controversial and doesn't have any clear role yet in deciding who should get tarceva and who shouldn't. It isn't a test that is routinely used yet, because we really haven't clarified how and where it should be used to help us predict prognosis or change treatment recommendations.

So that leaves me thinking it's ok. At least there's good news and I also read today that well-differentiated tumors fare better in survival rates. That also encourages me. I don't know why I'm still worrying about this. I guess I just can't shake it.

[ernrol]

Your mom can still recieve Tarceva outside of a trial. If her doctor thinks that it may help, then I think he can try it.

Stay positive,

Ernie

[DrWest]

This field is really so new that there really isn't a lot of data here. Tumors expressing EGFR tend to have a worse prognosis in some early studies, but that's before tarceva or other EGFR-based treatments were available. It's not clear whether that's really true now that anti-EGFR therapy is available.

The is also a little some evidence that patients with tumors with EGFR mutations may have a better survival than patients without mutations, but that may be the case whether they receive EGFR-based therapy or not. It's still too early to say anything definitive.

-Dr. West

[mary colleen]

Mitchell... I read this as being "value-neutral", as we say in my world of math statistics.

However, in my world of gut feelings (a different matter....) your lovely mother is going to do GREAT.

Please tell Kathy I say hi!

MC