Task force suggests annual lung cancer screenings

Doctors advise


Each year, more than 228,000 Americans are diagnosed with lung cancer. The vast majority of them (90 percent) will die from the disease. Lung cancer is the leading cause of cancer death in the United States, killing almost 160,000 Americans annually or roughly 27 percent of all cancer deaths in this country.

Smoking is the biggest risk factor for developing lung cancer, resulting in about 85 percent of cases. Last month, the U.S. Preventive Services Task Force (USPSTF), an independent, non-governmental panel of experts in prevention and evidence-based medicine, issued draft recommendations for new screening guidelines for lung cancer.

Specifically, the task force suggests people at high risk for lung cancer – smokers – undergo annual low-dose CT scans to boost chances of early disease detection. We asked Dr. Scott Lippman, director of the UC San Diego Moores Cancer Center, to review the USPSTF recommendations and what they mean.

Q: How significant are the draft recommendations for lung cancer screenings? What do they say about the health risk of CT scans?

A: The recommendations are a huge step forward for a population at high risk for lung cancer -- smokers. The National Lung Screening Trial reported a 20 percent decrease in mortality among smokers receiving low-dose CT lung screening. Importantly, the recommendations will immediately allow Medicare patients to be reimbursed for the exam. I expect other insurance providers will follow.

The health risks of yearly low-dose CT exams are minimal compared to the benefit of early detection of cancer. The radiation dose of a CT lung screening is equivalent to six months of unavoidable natural background radiation.

One of the biggest benefits of the recommendations is the greater opportunity for the screening team to discuss cessation in current smokers. Quitting the smoking habit is one of the best and fastest ways to lower risk of lung cancer. And talking to smokers about quitting in the setting of a CT scan is among the most effective and powerful ways of making that point.

Q: Describe the thought process of clinicians assessing a patient’s likelihood of developing lung cancer. What are they looking at? How do they rank the different risk factors?

A: The study looked mostly at the cumulative amount of smoking. This was the only risk factor considered. In reality, other factors such as exposure to asbestos, radon, prior history of radiation and chronic obstructive pulmonary disease also play a role. These are issues that a clinician will also examine to assess cancer risk.

Q: What is a “pack year?”

A: It’s a measure that can help a physician determine your risk for developing lung cancer. A pack year is the amount of cigarette packs (20 cigarettes) smoked daily times the number of years. A patient who smoked a pack a day for 30 years would have a 30-year pack history. Someone who smoked three packs a day for 10 years also has a 30-year pack history.

Q: Prevention and early detection are clearly the best ways to address lung cancer, but what about treatment in later stages? Is there any optimism in this area? Why has lung cancer proved particularly intractable to effective treatment?

A: This is a tough question to answer. There’s something about the biology of lung cancer that we do not yet completely understand. But that said, there have been advances, particularly in Stage IV cancer, such as the identification of novel broken genes (oncogenes) and certain drug developments.

The key issue here is that virtually all of the recent major advances in personalized therapy of lung cancer have been in non-smoking-related lung cancer. Smoking-related lung cancer remains a major clinical challenge, which makes CT screening and early detection all the more imperative.


