Comparing More Versus Less Frequent Monitoring to Diagnose Lung Cancer Early -- The Watch the Spot Trial

PCORI has identified the need for large studies that look at real-life questions faced by diverse patients, caregivers, and clinicians. To address this need, PCORI launched the Pragmatic Clinical Studies initiative in 2014. Pragmatic clinical studies allow for larger-scale studies with longer timelines to compare the benefits and harms of two or more approaches known to be effective for preventing, diagnosing, treating, or managing a disease or symptom. They focus on everyday care for a wide range of patients. This research project is one of the studies PCORI awarded as part of this program.

This research project is in progress. PCORI will post the research findings on this page within 90 days after the results are final.

What is the research about?

Every year, about 1.5 million Americans learn they have a nodule, or a spot or small growth, on their lungs. Most small nodules are harmless, but some are caused by cancer. Lung cancer is the leading cause of cancer deaths in the United States. The most common type of lung cancer is sometimes curable if found early.

Professional medical groups recommend regular lung cancer screening for people who smoke or have a history of heavy smoking. The goal of screening is to find lung cancer at an early stage, when successful treatment is possible. A scan of the chest, called computed tomography or a CT scan, is the most accurate test for lung cancer. If a CT scan finds a nodule, doctors may recommend regular follow-up CT scans to check whether the nodule grows or changes over time. However, doctors don’t always know how often to scan patients who have a nodule.

One drawback of CT scans is that doctors may find growths that aren’t cancer. As a result, some patients get follow-up scans, tests, surgeries, or treatment that they don’t need. Patients and their families may also worry needlessly. In this study, the research team is comparing less and more frequent follow-up CT scans to find lung cancer early.

Who can this research help?

This research can help people with small nodules in their lungs and their doctors decide how often to repeat CT scans to see if a nodule is growing, which makes cancer much more likely.

What is the research team doing?

The research team is enrolling more than 47,000 patients at 26 hospitals over 20 months. The study focuses on adults ages 35 and older with small nodules in their lungs. Doctors found the nodules either by screening or by accident while doing a chest CT scan for some other reason. The team is assigning patients by chance to have either more frequent or less frequent follow-up CT scans. Doctors decide on the number of CT scans based on each patient’s risk factors and the nodule’s traits. The research team estimates that patients who have less frequent screening will get two CT scans for about every three scans given to patients who receive more frequent follow-up. 

The research team is following patients for two years to see if the cancerous nodules grow to a more advanced and less treatable stage of disease. The team is tracking how long patients live after a cancer diagnosis. The researchers also look at how many cancer-related tests and surgeries patients have, the radiation dose used for CT scans, how closely doctors followed screening recommendations, and how often patients got CT scans prescribed for them. Using internet surveys, the team is measuring patients’ emotional health and general health status two months after screening and then again each year.

A group of researchers, patients, doctors and other healthcare professionals, advocacy groups, and professional societies helps design and carry out the study.

Research methods at a glance