Erbitux vs. Tarceva - 1257606

Laurielu, Excuse me for being so late in my reply. I must confess I read it earlier this morning and while looking for relevant info I came across your previous question about erbitux vs tarceva for maintenance and thought it was the same thread and Dr. West had responded. It's here, http://cancergrace.org/topic/erbitux-as-maintenance

Tarceva and erbitux are different enough to not worry about that comparison. Let me leave you with a couple of post on the subject of tarceva in people without the egfr mutation.
http://cancergrace.org/lung/2010/09/21/benefit-from-egfr-tki-if-egfr-wt/
While you probably won't have access to the testing there is plenty of encouraging info in this post about trying tarceva. http://cancergrace.org/lung/2013/06/12/prose-trial-veristrat/

This post discusses tarceva and other treatment options, http://cancergrace.org/lung/2010/10/04/lung-cancer-faq-2nd-line-nsclc-o…

I know you will feel better once you've made a plan,
Janine

The two drugs are more different than you might imagine. It's true that they both target EGFR, but the similarity ends there. EGFR spans the membrane of the cell. Tarceva acts inside the cell to shut down signaling from EGFR that leads to cell growth and survival. Cetuximab acts outside the cell. In colon cancer, shutting down EGFR signaling seems important. In contrast, in lung cancer, it doesn't seem to matter as much. Rather, our best evidence is that cetuximab causes ADCC, or antibody directed cellular toxicity. It seems to help the immune system to recognize the cancer cell as foreign and to kill it. For erlotinib, the best predictor of response is the presence of EGFR mutation. Veristrat, a blood test, seems to be able to predict patients who will benefit less from tarceva in the 2nd line as compared to chemo. For cetuximab, the best predictor of efficacy is a weird formula for evaluating the amount of EGFR present on the cell surface.