Overview

Lung cancer screening is a way to find some lung cancers early, before a person has any symptoms of the cancer.

Lung cancer screening may help those who have the highest risk for lung cancer—people age 50 and older who are or were heavy smokers. For most people, who aren't at increased risk, screening for lung cancer probably isn't helpful.

Screening won't prevent cancer. And it may not find all lung cancers. Lung cancer screening may lower the risk of dying from lung cancer in a small number of people.

Guidelines

Lung cancer screening is recommended for people age 50 and older who are or were heavy smokers. That means people with a smoking history of at least 20 pack years. A pack year is a way to measure how heavy a smoker you are or were.

To figure out your pack years, multiply how many packs a day on average (assuming 20 cigarettes per pack) you have smoked by how many years you have smoked. For example:

• If you smoked 1 pack a day for 20 years, that's 1 times 20. So you have a smoking history of 20 pack years.
• If you smoked 2 packs a day for 10 years, that's 2 times 10. So you have a smoking history of 20 pack years.

Experts agree that screening is for people who have a high risk of lung cancer. But experts don't agree on what high risk means. Some say people age 50 or older with at least a 20-pack-year smoking history are high risk. Others say it's people age 55 or older with a 30-pack-year history.

To see if you could benefit from screening, first find out if you are at high risk for lung cancer. Your doctor can help you decide your lung cancer risk.