Can you have adeno and squamous lung cancer at the same time? What is the significance for treatment? 2 biopsies --- one from main lung mass showing squamous, one from lymph node showing adeno.

Yes... It is possible that there are two different cancers. It may also be that the primary tumor is a combination of the two (adenosquamous) and the biopsy only sampled one part. Adenosquamous tumors contain adenocarcinoma and squamous cell carcinoma. And either or both types of cancer may spread to lymph nodes.
In. In addtion to dr. Thompson's answer. Having 2 different histologies from two locations within the chest are usually the result of 2 different lung cancers. The treatment modality chemo/radiation/surgery or combination of these is determined by the highest stage. Example if likely adeno is higher stage because of lymph node involvement, this likely dictates which modality should be used.
Absolutely. You may have two primaries. Or around 10% of adenocarcinomas have a bit of squamous, and around 10% of squamous cell carciomas has a bit of "adeno". I must simply with you the best -- and hope that the molecular studies show the possibility that this will respond to one of the new medicines. We have lots more today for this than we used to. Best wishes.
Yes.. Yes. 2 different non-small cell lung cancer (nsclc) pathologies are possible. The significance is that some treatments are either not indicated or have less data for squamous cell carcinoma (eg, pemetrexed, bevacizumab, tarceva). Many lung cancer chemotherapies will treat both.