What Is The Treatment Of Lung Cancer In Stage 4 ?

My mother, age 78, has been diagnosed with lung cancer, in both lungs, stage four. She lives out of state and her children have just recently come to her aide. we noticed the club fingers right away and learned of their relation to lung cancer. We wonder how long such clubbing takes to produce that effect. She has smoked for 65 years regualrly, and a lot. She is coughing a lot and has significant weight loss. What benefit will a biopsy possibly provide? Us adult children are concerned the procedure is not worth the risk of a possible punctured lung and or introducing oxygen into the cancer. She also has myasenya gravis (my incorrectspelling is phoenetic) since she was 30. What may a biospy tell us that we need to know?