Tarceva typically helps people with an EGFR mutation. If your mom has this mutation she may live for a long time with stable disease if she responds to Tarceva. When you say everything what does this mean? There are some people who respond to Tarceva who are not EGFR but they have a shorter response time.
Here are some suggestions
Is she at a top name cancer facility and does she have an expert treating her.
Has she been mutation tested..go to "lets test now to learn more" on the web
Has she had a second opinion done? Go to the Bonnies J. Addario site and watch all of the webinars in the library or got to cancer grace and read that material.
There are many clinical trials , targeted therapies and other options. Tell me how I can help you after you read this material and I will do my best to try.