Lung cancer

Can someone help me?  I was told today I have lung cancer.  I had a ct scan two weeks ago and I needle biopsy one week ago.  I have a 3.7 cm mass in my right lower lobe and a 2.5 cm lymph node close by.  My local pathologist could not identify what type of cancer it is so the specimen was sent to a large city university and they could not identify what kind it is either.  How can you know it's cancer but not know what type?  Has anyone ever heard of this before?