CT scans reveal body composition changes preceding pancreatic cancer diagnosis

People who develop pancreatic cancer experience measurable changes in body composition years before diagnosis that differ from those seen in similar individuals without cancer, according to a Mayo Clinic study led by former Mayo Clinic research fellow, Aleksander Bogdanski and published in Pancreatology.

Pancreatic cancer remains one of the deadliest cancers, largely because most patients are diagnosed after the disease has already spread. Current surveillance programs focus primarily on people with inherited genetic risk or strong family histories, yet most pancreatic cancers occur outside those high-risk groups.

Researchers found that patients who developed pancreatic ductal adenocarcinoma (PDAC), the most common type of pancreatic cancer, experienced steeper declines in visceral and subcutaneous fat over the three years before diagnosis compared with matched controls. The findings suggest that routinely acquired CT scans may capture physiological changes associated with pancreatic cancer before it is clinically detected. To the researchers' knowledge, this is the largest controlled study to examine prediagnostic body composition trajectories in patients who later developed pancreatic cancer.

The study analyzed abdominal CT scans from 1,825 patients with pancreatic ductal adenocarcinoma and 3,650 matched controls from Mayo Clinic sites in Arizona, Florida and Minnesota. Using an artificial intelligence-based body composition tool, researchers measured changes in skeletal muscle, subcutaneous fat and visceral fat over time.

Pancreatic cancer often develops silently, making early detection extremely challenging. These findings suggest that routine CT scans may capture physiological changes associated with pancreatic cancer before patients are diagnosed."

Yan Bi, M.D., Ph.D., gastroenterologist, Mayo Clinic and senior author of the study

Compared with controls, patients who developed pancreatic cancer experienced significantly steeper declines in both subcutaneous and visceral fat during the three years before diagnosis. Differences in muscle mass were most apparent during the final 12 months before diagnosis.

"Our study shows that body composition changes associated with pancreatic cancer are detectable on routine CT scans and differ from the changes observed in similar patients without cancer," says Michael Wallace, M.D., a Mayo Clinic gastroenterologist and corresponding author of the study. "To our knowledge, this is the largest controlled study to evaluate these prediagnostic body composition trajectories and one of the first to assess whether they can help distinguish patients who go on to develop pancreatic cancer from those who do not."

Building toward earlier pancreatic cancer risk detection

Researchers also evaluated whether longitudinal changes in muscle and fat measurements could distinguish patients who later developed pancreatic cancer from matched controls. The body composition measures demonstrated moderate discriminatory ability, suggesting they may provide additional information for future risk assessment strategies.

The researchers are working on developing algorithms that incorporate body composition measures along with other routinely collected clinical factors and imaging biomarkers to identify patients at increased risk.