Lung cancer: to screen or not to screen

Science Spotlight

Lung cancer: to screen or not to screen

From the Roth Group, Public Health Sciences Division

Aug. 20, 2018

Lung cancer incidence and death rates have been declining in the U.S. in both men and women; however, lung cancer remains the number one cause of cancer death. In 2013, the U.S. Preventive Services Task Force (USPSTF) issued a B level recommendation for lung cancer screening of asymptomatic individuals using the low-dose computed tomography (LDCT) imaging technique. The recommendation is specific for patients at high-risk, adults 55 to 80 years of age who have a thirty pack-year smoking history and are either current smokers or have quit within the past fifteen years. The recommendation was supported by results from the large-scale National Lung Screening Trial that reported a 20% reduction in mortality from lung cancer in patients randomized to annual LDCT as compared to those randomized to annual chest radiography.

The updated recommendation was significant because any A or B recommendation by the USPSTF that includes preventative services mandates coverage by health insurance without any cost to patients. Thus, because lung cancer is one of the most commonly diagnosed cancers in the US and the overall five-year survival rate for all stages combined is less than 20%, the LDCT recommendation could impart a substantial public health impact if eligible patients elect to undergo the screening. Dr. Joshua Roth in the Public Health Sciences Division and collaborators recently published a paper in PLoS One that describes motivating factors of individuals who decide to receive LDCT screening.

The new study is the first to focus specifically on lung cancer screening motivating factors in a community-based setting. Understanding motivations from the patient’s perspective may be useful to improve lung cancer screening outreach efforts. As explained by Dr. Roth, “recent studies have shown that only about 3% of people who are eligible for lung cancer screening (based on age and smoking history) have received a screening scan in recent years. We need to develop strategies to increase appropriate screening in order to catch more lung cancer cases at early stages when prognosis is better and there is potential for cure.”

Graph depicting patient reported motivations for undergoing low-dose computed tomography for lung cancer screening.

Patient reported motivations for undergoing low-dose computed tomography for lung cancer screening.

Image provided by Dr. Roth

To learn more about the factors that drive patients to undergo lung cancer screening, the authors conducted a qualitative study of members of the Kaiser Permanente Washington system. Twenty patients who met the USPSTF criteria for LDCT screening and who had received a ‘negative’ test result were enrolled into the study. All participants underwent a semi-structured telephone interview that was designed to inform the study team on factors that contributed to the decision to undergo lung cancer screening.

Four major themes on motivations to complete LDCT screening emerged from the study (see figure). Nearly all participants (85%) indicated that trust in the referring clinician was a primary factor that led to screening and that prior to discussions with the physician most participants did not know they were eligible for screening. The second major theme identified was the benefit of lung cancer early detection, identified by 75% of all participants. Perception of limited harm as a result of LDCT was a third major factor, identified by nearly half of all participants. The fourth major theme to emerge, discussed by nearly a third of study participants, was the experience of having friends or family members with advanced cancer and the associated low quality of the end of life. Taken together, Dr. Roth described the importance of these results, “Our findings provide new insights about patient motivations to screen and can potentially be used to improve lung cancer screening uptake and shared decision-making processes.”

Dr. Roth indicated that follow-up studies could quantitatively assess the magnitude of effect for each of these newly identified motivating factors. “For example, we could survey people eligible for screening about motivations for/against participating and compare answers between those who did/didn't ultimately participate. That type of study design would help us to understand which of the motivations identified in this study are most strongly associated with participation, which could in turn inform development of shared decision making interventions intended to boost screening participation,” said Dr. Roth.

This research was supported by the Agency for Healthcare Research and Quality.

Roth JA, Carter-Harris L, Brandzel S, Buist DSM, Wernli KJ. 2018. A qualitative study exploring patient motivations for screening for lung cancer. PLoS One. doi: 10.1371/journal.pone.0196758