CT Screening Greatly Boosts Lung Cancer Survival: Study

November 8, 2023
Ernie Mundell HealthDay Reporter

For smokers and former smokers, getting annual CT scans of the chest to catch lung cancers early dramatically improves survival, new research shows.

Many people may believe lung cancer to be swiftly fatal. However, the new report found that 81% of people whose tumors had been spotted by CT screenings were still alive 20 years later.

And if patients were lucky enough to have their cancer diagnosed when it was in its earliest stage, 20-year survival rose to 95%, the researchers found.

"It is the first time that 20-year survival rates from annual screening have been reported,"study lead author Dr. Claudia Henschke noted in a news release from the Radiological Association of North America.

She's a professor of radiology and director of the Early Lung and Cardiac Action Program at the Icahn School of Medicine at Mount Sinai in New York City.

"This 20-year survival rate of 81% is the estimated cure rate of all participants with lung cancers diagnosed by annual screening," Henschke said. "This is a huge benefit compared to waiting for a diagnosis that, in usual care, is symptom-prompted."

Despite steady declines in smoking among Americans, lung cancer remains the nation's leading cancer killer.

Because it's often detected only after symptoms begin, the average five-year survival rate for lung cancer is just under 19%, and more than half of Americans with lung cancer die within a year of diagnosis.

Spotting tumors early -- before symptoms arise -- could change those numbers, however. According to the American Lung Association, just 16% of lung cancers are currently diagnosed at an early stage.

Because low-dose CT screening can spot early-stage lung cancers, the American Cancer Society last week expanded its guidance on who should get the screening, and how often. The updated guidelines advise annual CT screening for smokers and former smokers starting at age 50 and continuing until age 80.

In addition, those who have smoked at least 20 cigarettes a day for 20 years or more should be screened; the previous recommendation was 20 cigarettes a day for 30 years.

The new study helps bolster the life-extending potential of CT screening for lung cancer patients.

Beginning in 1992, Henschke's team at Mount Sinai helped create the International Early Lung Cancer Action Program, which involves over 89,000 participants at 80 institutions worldwide.

Looking at follow-up data, in 2006 the research showed a 10-year survival rate of 80% for lung cancer patients whose disease was spotted by CT screening.

The latest report extends those findings to 20 years of follow-up.

"We were excited to see that the estimated cure rate we reported in 2006 has persisted after 20 years of follow-up,"Henschke said.

A total of 1,257 of the program's participants ended up being diagnosed with lung cancer, and most (81%) had their tumors spotted at Stage 1, before the cancer had a chance to spread to lymph nodes.

She noted that 25% of people who develop lung cancer have no history of smoking, but may have been exposed to secondhand smoke through a partner or family member. The new study suggests that regular CT screening might help this group, too.

The bottom line, according to Henschke, is that "lung cancer can be cured if you enroll in an annual screening program using a well-defined protocol and comprehensive management system. It is important to return for annual screening."

Another influential group, the U.S. Preventive Services Task Force, also advocates for regular CT screening for lung cancer. Their guidelines advise annual screening in adults aged 50 to 80 who have a 20 pack-year smoking history and now smoke or have quit within the past 15 years.

The new findings were published Nov. 7 in the journal Radiology.

More information:

Find out more about CT screening for lung cancer at the American Lung Association.

SOURCE: Radiological Society of North America, news release, Nov. 7, 2023

Cancer: Lung