Catching Lung Cancer Early with Low-Dose CT

Lung cancer has been the leading cause of cancer death in the United States for nearly four decades, claiming more lives every year than breast, colon, and prostate cancer combined. It is often quiet, showing no signs until it has already spread. Thanks to low-dose computed tomography (LDCT), people no longer have to wait for symptoms to know something is wrong.  

This quick, painless scan is now recommended by the U.S. Preventative Services Task Force as an annual screening test to catch lung cancer in its earliest stages-making it one of the best tools we have for prevention.

What exactly is a low-dose CT?

Think of a CT scan as a camera that takes thousands of detailed pictures of your lungs, then stitches them together to create a 3D image. A low-dose CT uses the same technology but with a much smaller amount of radiation.

This lower dose of radiation means it is safe enough to use every year for people at a higher risk of developing lung cancer. “Low-dose CT is used specifically for prevention,” says Bryan Payne Stanifer, MD, founding director of the lung cancer screening program at Columbia University Irving Medical Center. “It gives us a look inside the lungs long before symptoms appear, which can make a big difference in prognosis and treatment.”

LDCT is not new, but its role in prevention has increased greatly since national guidelines endorsed it more than a decade ago. Studies now show that annual scanning using LDCT can reduce lung cancer deaths by more than 20%. Despite this life-changing evidence, most eligible adults aren’t getting the screening.

Why aren’t more people getting screened?

If the LDCT scan works so well and has been around for over a decade, why is lung cancer still claiming so many lives? Part of the answer is awareness. “Many people who qualify for LDCT simply don’t know it exists, or assume it is something their doctor will bring up if they need it,” says Dr. Stanifer. “Others worry about radiation exposure or cost, even though LDCT uses minimal radiation and is covered by Medicare and most insurance plans for eligible adults.”

Access can also be a barrier. “For someone juggling work, family, or transportation challenges, scheduling a hospital scan can feel impossible,” says Dr. Stanifer. “These logistical challenges often mean that those who would benefit most from screening are sometimes screened the least.”

LDCT is also not recommended for everyone. It is most effective when used for people at higher risk for developing lung cancer. Current guidelines recommend annual screening for adults aged 50 to 80 (50–77 if you’re on Medicare) who currently smoke or quit within the last 15 years and have at least a 20 pack-year smoking history. Screening can stop once someone has been smoke-free for 15 years or if they develop a major health problem that would limit treatment options. 

Most of the time, LDCT findings are not cancer. The scan is sensitive, which means it can pick up tiny nodules that are often harmless. If something looks unusual, doctors will usually recommend another scan in six to twelve months to see if it changes. Occasionally, a biopsy or more imaging may be needed, but for most people, LDCT brings reassurance and peace of mind.

Bringing LDCT screening to more New York neighborhoods

For many, simply knowing about LDCT scans doesn’t make it easier to get one. To make these scans more accessible, the Herbert Irving Comprehensive Cancer Center (HICCC) along with its partners has launched New York City’s first mobile lung cancer screening van, a 40-foot unit equipped with the same advanced LDCT machine that is found in hospital imaging centers.

The van parks outside community clinics, churches, and neighborhood health fairs across New York City neighborhoods with high burdens of lung cancer, bringing lung screening directly to the people and communities who need it most.

“Too often, geography and logistics get in the way,” says Dr. Stanifer. “The goal isn’t just to find cancer—it’s to make sure no one falls through the cracks. Early detection should belong to everyone.”