ASCO 2018: Few heavy smokers screened for lung cancer

A small minority of heavy smokers are screened for lung cancer, despite recommendations from the US Preventive Services Task Force (USPSTF) and American Society of Clinical Oncology (ASCO), according to data presented at the 2018 ASCO Annual Meeting in Chicago, IL.

“Lung cancer screening rates are much lower than screening rates for breast and colorectal cancers, which is unfortunate,” remarked lead study author, Danh Pham, MD, James Graham Brown Cancer Center, University of Louisville, Kentucky. “It is unclear if the screening deficit is due to low provider referral or perhaps patient psychological barriers from fear of diagnosis. Lung cancer is unique in that there may be stigma associated with screening, as some smokers think that if cancer is detected, it would confirm they’ve made a bad lifestyle choice.”

In 2013, the USPSTF recommended annual screening with low-dose computed tomography (LDCT) in smokers aged between 55 and 80 years with ≥30 pack years, applying to those who either currently smoked or who had quit during the prior 15 years. 

Experts have yet to elucidate the number of LDCT screens conducted in the US, as only estimates are available. “Our study aims to present the number of screening LDCTs being performed across the United States,” the investigators wrote.

The authors performed a statistical analysis that mined the Lung Cancer Screening Registry (LCSR) for the total number of 2016 LDCT screens performed at 1,796 screening sites in four US census regions: the Northeast, Midwest, South, and West. They used results from the 2015 National Health Interview Survey (NHIS) to estimate the number of heavy smokers eligible to be screened according to USPSTF guidance.

In total, the team identified 7,612,975 patients. Only 1.9% (n=141,260) received LDCT screening, with the following screening percentages by regions:

• Northeast: 3.5%
• Midwest: 1.9%
• South: 1.6%
• West: 1.0%

Notably, most heavy smokers lived in the South, which has the most accredited screening centers. However, the screening rate in this region was second lowest. Of those patients screened, 85% were offered smoking cessation interventions by their providers across all regions.

“Annual LDCT screening remains inadequate following USPSTF recommendations despite the time since implementation and potential to prevent thousands of lung cancer deaths each year,” the researchers concluded. “It remains unclear why the lung cancer screening rate is dramatically lower than other cancer screening modalities such as mammography and colonoscopy. Further initiatives are needed including awareness programs and mandating lung cancer screening as a national quality measure.”

ASCO President Bruce E. Johnson, MD, stated: “This study makes a strong case that our country needs an effective public service campaign about encouraging lung cancer screening. Public service campaigns from the 1990s encouraged women to get mammograms, saving many lives in subsequent years. We need something similar to encourage current and former heavy smokers to get screened for lung cancer.”

This study was funded by the Bristol-Myers Squibb Foundation.