Doctors say that a drug that boosts the immune system may help before lung cancer surgery. It gave dramatic results when used with chemotherapy in patients with operable lung tumors. The study of about 350 people tested chemo and the Bristol Meyers Squibb drug Opdivo. About a quarter of the patients given the combo had no signs of cancer remaining once they ultimately had surgery. Drugs like these are often used after surgery and many studies are testing them before as well. Results were reported over the weekend at a cancer conference.