According to the U.S. Centers for Disease Control and Prevention, 40 percent of all cancers diagnosed in the U.S. since 2014 were associated with overweight and obesity. Can weight loss associated with bariatric surgery reduce the risk of some cancers? Maybe, according to a recent meta-analysis of several key studies, which found that people with obesity who had bariatric surgery had a substantially lower risk of developing five types of solid tumors. But it remains unclear if the factors driving the risk reductions might be physical, behavioral, or both.
Now, a new study funded by the National Cancer Institute (NCI) will use PCORnet resources to understand if one of those factors is a change in adherence to recommended preventative cancer screenings after bariatric surgery. We know, for example, that women with obesity are less likely to undergo regular screenings, like pap smears and mammograms. Investigators for the new PCORnet® Study will determine if undergoing bariatric surgery influences such trends.
“People living with obesity are at higher risk for many types of cancer, and yet they tend to have lower rates of cancer screening than other individuals. As a result, when cancer occurs, it may be detected later, which can contribute to worse outcomes,” said Kathleen McTigue, principal investigator for the PaTH Clinical Research Network, one of six PCORnet® Network Partners contributing to the NCI study. “This study will help us better understand the impact of bariatric surgery on preventive screening practices.”
McTigue believes the challenges that people who are living with severe obesity face regarding cancer screening could be reduced following bariatric surgery. For example, in the process of preparing for surgery, patients may become more familiar with the healthcare system and aware of the need for screening. Likewise, weight loss may lesson concerns related to body image and modesty.
Building on earlier PCORnet-leveraged work
NCI’s interest in PCORnet as a resource to fuel its research stemmed from the successful PCORnet® Bariatric Study, which launched in 2016 as a retrospective, observational comparative effectiveness study designed to capture accurate estimates of 1-, 3-, and 5-year benefits and risk of bariatric surgery. Using PCORnet resources, the study team collaborated with 41 sites across the U.S. to glean insights related to more than 46,000 patients. Its results continue to provide important reference information for patients and providers about real-world bariatric surgery outcomes.
“NCI approached us through the PCORnet® Front Door to see if we could leverage the patient and data partnerships established with the original bariatric study to bring new insights around cancer screenings to light,” said McTigue. “It has been wonderful to see the Network recognized for its capacity to support research at scale and surface new answers around cancer and obesity, two important topics that impact millions of Americans.”
The project will find answers by looking at de-identified electronic health record (EHR) information accessible across six sites participating in PCORnet. As with all PCORnet® Studies, the NCI study will embed patient input throughout the project lifecycle, with bariatric surgery recipient Neely Williams serving on the study leadership team and sitting on its Stakeholder Engagement Committee.
“I am thrilled to be a part of this important research, which will bring more clarity to the relationship between bariatric surgery and cancer—a question that is certainly of great interest to bariatric surgery recipients like me,” said Williams. “The participation of myself and others on NCI’s Stakeholder Engagement Committee for this study will help ensure the lived experience of patients is considered in the development and execution of this research.”
Looking to the future
McTigue hopes that this initial study is only the beginning. This work may ultimately lead to a larger NCI project exploring other connections between weight loss and cancer via PCORnet. Such work would link EHR data with tumor registry data, building from the PCORnet® NET-PRO Study, which is currently comparing the effects of different treatment approaches on neuroendocrine tumors.
“We are excited by the potential for PCORnet to serve as a powerful resource for conducting large-scale cancer research,” said McTigue. “Cancer is consistently a leading cause of death in the US, and over 40% of US adults live with obesity. We need to learn all we can as quickly as possible—and thankfully, PCORnet offers the infrastructure to make it happen.”