The presence or absence of PD-L1 tells whether or not immunotherapy will work. I have PD-L1 with strong expression, but I'm still not a candidate for immunotherapy because I have the EGFR Exon 19 mutation. If an Oncologist tells someone they are not a candidate for immunotherapy, it means it won't work. 85% of lung cancer cases are non-small cell, so that's no help. She needs to ask her doctor what else he knows besides non-small cell adenocarcinoma. Nowadays, they're able to identify a lot of different subtypes, each with their own treatment recommendations.

We still have an awful lot to learn about lung cancer and cancer in general, but we are past the point of "try it and see if it works." At least for the most part. There are always exceptions.