Hello Tarceva.  Welcome.  I hadn't heard of Tarceva but that is okay (for me anyway) because each time I read something I don't understand I go and look it up, gradually acquiring bits and pieces of knowledge.

I also looked up previous posts where Tarceva had been discussed; don't know if you are interested in looking at these; some are a few years old, others more recent.  If you would like to take a look click on the words Search Forum above your post.  In the box that opens up type Tarceva and you will get access to the previous posts.  Best wishes.  Annie