San Francisco ? Dr. Norman Shumway, the first surgeon to perform a successful heart transplant operation in the United States, died Friday of lung cancer, a Stanford University spokeswoman said. He was 83.

Shumway died at his home in Palo Alto, spokeswoman Ruthann Richter said.

Shumway completed the first successful U.S. adult heart transplant in 1968, but he may be best known for continuing with transplant research as many others quit.

During the 1970s, when most recipients died soon after their operations because of organ rejection or infections, many surgeons became discouraged and stopped performing transplants. But Shumway stuck with it and built a large transplant research team at Stanford that found ways to overcome rejection problems.

Shumway developed tests that enabled the use of smaller doses of dangerous rejection drugs and was one of the first transplant surgeons to begin using the safer rejection drug cyclosporine.

Ultimately, he dramatically improved survival rates for transplant recipients.