CHICAGO — Northwestern Medicine surgeons have successfully performed a double lung transplant on a man with terminal lung cancer, they announced Thursday — an extremely rare surgery that could open the door to helping more patients with certain types of cancer. Albert Kouhry, 54 of Chicago, underwent the surgery six months ago, after developing Stage 4 lung cancer. His new lungs are now working well, and he seems to be cancer-free. Lung transplants should not replace standard treatments for lung cancer, which include surgery, chemotherapy, immunotherapy and radiation, said Dr. Ankit Bharat, No…