While CT has positively impacted clinical diagnosis, incidental findings have become an unforeseen side effect. Renal masses, benign or otherwise, are among the most common of these findings, and the risk of nephrectomy is closely associated with incidental detection of these masses. Recent research examined how living in an area with high rates of CT affects nephrectomy risk.

“Whether it entails radical or partial nephrectomy or renal ablation, treatment for an incidentally detected renal mass is associated with a significant risk of harm,” wrote corresponding author H. Gilbert Welch, MD with the Dartmouth Institute for Health Policy and Clinical Practice at Dartmouth College. “In addition to the perioperative case-fatality rates … all these interventions require general anesthesia, elevating the risk of cardiovascular events.

New England researchers dug through data from 15 million fee-for-service Medicare beneficiaries age 65 to 85 across 306 hospital referral regions (HRRs) in the U.S.

Published in the February issue of JAMA Internal Medicine, the study indicated 43 percent of these recipients received either a chest or abdominal CT scan from 2010 to 2014.

Regional risk did vary across HRRs from 31 percent in Santa Cruz, California, to 52 percent in Sun City, Arizona. Risk also varied in regions with more than 50,000 beneficiaries, from 34 percent in San Francisco to 50 percent in Miami.

However, the team determined that Medicare recipients residing in high-scanning regions face higher risks of total nephrectomy.

The study authors stressed the findings do not indicate surgeons are purposely performing more surgery, but what is less understood are the interconnected reasons for the increased risk of the kidney procedure.

“Many clinicians understand the downsides of incidental detection. Nevertheless, they are caught in a complex web of forces promoting earlier cancer diagnosis and earlier intervention: strong financial interests, fear of litigation, and unquestioning beliefs among the public about the value of early diagnosis and treatment,” wrote Welch et al. “More balanced medical care will require addressing these forces.”