Geography, not patient need, driving endoscopic ultrasound utilization

Before the advent of endoscopic ultrasound, the only way to determine the severity of pancreatic cancer was through surgery. Today, the minimally invasive procedure is used to stage thousands of patients per year, often part of their pre-surgical preparation.

A group of researchers from the University of Wisconsin School of Medicine and Public Health found patients who underwent endoscopic ultrasound (EUS) had longer times-to-surgery than those who didn’t. Led by resident Ryan Schmocker, MD, the team linked certain geographical areas and institutional factors to a higher likelihood of undergoing EUS, in addition to a baseline increase in utilization nationwide, publishing their research in the Official Journal of the International Hepato-Pancreato-Biliary Association.

Whether or not a patient received an ultrasound was influenced more by geography than the needs of the patient, prompting a question: Are the right patients receiving EUS?

The Surveillance, Epidemiology and End Results (SEER) Medicare-linked database was used to gather data on patients receiving EUS from 2000 and 2007, producing a curious geographical distribution: About half of the 14 SEER statistical areas had much higher use, but it wasn’t concentrated in any specific region of the U.S. This stochastic distribution points to variation in provider practice rather than disease severity, according to co-author Emily Winslow, MD, an associate professor of surgery.

“In certain areas, this is how their diagnostic workup is done,” she said in an interview with Radiology Business. “A radiologist in a certain area may be more likely to recommend this test in their report when compared to elsewhere in the country.”

While the geographic distribution wasn’t centered around academic medical centers, the team did find a slightly higher rate of EUS at National Cancer Institute-designated cancer centers and some academic hospitals. Winslow said this is partially attributed to the concentration of specialists at these centers. In a community setting, it’s often community doctors referring to a surgeon for the first evaluation, instead of the gastroenterologist who might preform the EUS.

Particularly troublesome cases could be another reason for this uptick, according to Winslow.

“There’s a small percentage of the population that’s seen in an academic center because there’s a diagnostic dilemma,” she said. “That could be some of the reason there’s more EUS in an academic center: if there’s something peculiar about the clinical presentation. The trouble is, that probably doesn’t explain it all, then all academic centers would be similar.”

While future research is needed to determine if EUS is being overused, the best way to prevent misuse is to increase communication between gastrointestinal specialists and the general radiologists or clinicians who refer patients to them, according to Winslow.  

“This is an area of medicine that requires true multidisciplinary collaboration, in both diagnostic and treatment phases,” said Winslow. “I think it’s important that gastrointestinal doctors are incorporated into multidisciplinary teams to evaluate the necessity for endoscopic ultrasound, instead of just being asked to do the procedure by a variety of providers.”

This avenue of care is the most likely the best spot to intervene, according to Winslow. Establishing guidelines about what needs to happen before EUS can help radiologists send the right patients to gastrointestinal specialists.

“In general, we try to treat the patient and not the imaging finding, thinking carefully about when invasive testing needs to be done and when it can be avoided while keeping in mind it’s effect on the overall course of treatment,” she said.

Updated SEER data will be available within the next two years, representing an opportunity for Winslow and her colleagues to investigate the topic further. The team’s got their eye on interplay between rates of EUS in patients who receive chemotherapy or neoadjuvant therapy.

“Treatment for cancer is becoming better, but it’s also becoming more complicated,” she said. “We need to minimize the impact that that kind of progress has on patients, make sure it doesn’t introduce unnecessary complexity—ensuring that it helps people rather than creating barriers.”