New guidelines from the American Cancer Society say adults who currently smoke and those who used to smoke should be tested for lung cancer.

The screening process involves a computed tomography (CT) scan of the chest.

"We want to find the patients with lung cancer while they're still feeling fine. We want to find them at the earliest possible stage, at that point we can cure a person. We can cure a patient potentially with surgery alone without the need for chemotherapy or radiation,' says Dr. Michael Ebright, director of thoracic surgery at Stamford Health.

Doctors agree with the updated guidelines that recommend people start get screened at 50, instead of at 55.

"By changing our guidelines we're actually going to increase the number of eligible patients by about 37% which means about 5 million more Americans will be eligible for lung cancer screening." Dr. William Dahut, chief scientific officer at the American Cancer Society.

Ebright tells News 12 the years-since-quitting criteria should also be dropped since the risk of lung cancer increases with age.

"If you've been smoking a pack of cigarettes a day for 20 years or if you did in the past, the previous guidance only included people who smoked a pack a day for 30 years and disqualified those who quit more than 15 years ago. Not only is smoking addictive and very difficult to quit, many patients stopped smoking or started smoking well before anybody knew it was bad for you. Currently there are more patients that have quit smoking than are current smokers," says Ebright.

The American Cancer Society says lung cancer is the leading cause of cancer death in the U.S.