Story highlights The pair's research harnesses the body's immune system to attack cancer cells

"We are making progress now," one laureate tells cancer patients

(CNN) American James Allison and Japan's Tasuku Honjo have won the 2018 Nobel Prize in Medicine for a pioneering approach to cancer treatment.

The Nobel committee said the pair's research -- which harnesses the body's immune system to attack cancer cells -- amounted to a "landmark in our fight against cancer." The approach, known as immune checkpoint theory, had "revolutionized cancer treatment and has fundamentally changed the way we view how cancer can be managed," the committee said.

James Allison works at the University of Texas MD Anderson Cancer Center.

Allison said Monday that his son called at 5:30 a.m. and was the first to tell him that he'd won. Later in the morning, the Nobel committee called Allison with the news.

"I'm still in sort of a state of shock, and this is all still sinking in," Allison said.

"I was told by the Nobel committee when I was called this morning that this was the first prize they've ever given for cancer therapy," he said. "I'd like to just give a shout out to all the patients out there who are suffering from cancer to let them know that we are making progress now."