Spiral CT for high-risk patients: a new tool to catch lung cancer early

Smokers eligible for early screening.

A patient undergoes a spiral CT scan.

Early screening for lung cancer isn’t for everyone. “Roughly 85% to 90% of lung cancer cases are smoking-related,” notes John Abe, MD. “Overall, cases of lung cancer are trending down, but the number of new cases is still pretty high.”

That’s why early screening focuses on individuals with a history of smoking or past cancer diagnoses. More than 10 years ago, large-scale clinical trials confirmed the benefits of early screening.

“At Torrance Memorial, we were able to start an early screening program within a year of that published study,” says Dr. Abe. “We screen people who qualify as high-risk, and that’s primarily due to a history of smoking.”

There’s a catch to early and repeated screenings, though. Lung cancer is detected using CT scans, and over time the radiation from CT scans can itself become a health risk. That’s why Torrance Memorial offers low-dose (also known as spiral or helical) CT scans for annual lung cancer screening of high-risk individuals.

CT scans are essentially 3D X-rays. Spiral CT scans rotate the X-ray tube around the patient in a spiral motion. The process is eight to 10 times faster than a traditional CT scan, and spiral CT scans are especially good at capturing small nodules. The X-ray dose from a spiral CT scan is about 1/3 less than the dose from a regular CT scan, and for high-risk individuals the benefits of the screening outweigh the risks, Dr. Abe says.

Studies have shown low-dose CT scans in high-risk patients improve the survival rate by 25%, adds Khalid Eltawil, MD. “The whole idea behind early screening is early detection because the earlier you detect lung cancer, the more survivable it is.”