Study examines screening for pancreatic cancer in high-risk populations

Researchers from New England report in a new study that using a tumor marker, serum CA 19-9, combined with an endoscopic ultrasound if the tumor marker is elevated, is more likely to detect stage 1 pancreatic cancer in a high-risk population than by using the standard means of detection. The study appears in the July issue of GIE: Gastrointestinal Endoscopy, the monthly peer-reviewed scientific journal of the American Society for Gastrointestinal Endoscopy (ASGE).

Pancreatic cancer is the fourth leading cause of cancer death in the United States. Advanced disease at diagnosis correlates directly with worse overall survival. Symptoms of abdominal pain, jaundice, and/or weight loss often do not appear until the tumor is locally advanced or metastatic, at which point effective treatment options are very limited. By contrast, detection and resection of pancreatic cancer, when it is confined to the pancreas (stage 1 disease), improves overall survival. An effective screening protocol is urgently needed to detect earlier stage tumors. Imaging methods that have been used for pancreatic cancer screening include endoscopic ultrasound (EUS), CT, endoscopic retrograde cholangiopancreatography (ERCP) and magnetic resonance imaging/MRCP.

There has been limited success in screening younger populations using the tumor marker CA19-9, so more recent pancreatic cancer screening protocols have focused on high-risk populations.

It is estimated that 10 percent of patients in whom pancreatic cancer develops have at least one first-degree relative with the disease. Multiple cohort and case-control studies have demonstrated that a family history of a first-degree relative with pancreatic cancer significantly increases a patient's risk of the development of pancreatic cancer, approximately two to five-fold. The risk of the development of pancreatic cancer increases significantly as the number of affected family members increases. Advanced age is also a significant risk factor, and 93 percent of patients with pancreatic cancer present after the age of 50.

"Our hypothesis was that a high-risk population identified by age and at least one first-degree relative with pancreatic cancer can be successfully screened. Our objective was to determine whether early pancreatic neoplasia can be detected in a high-risk population by using tumor marker CA 19-9 followed by targeted endoscopic ultrasound. We also sought to determine whether this protocol was more likely to detect early stage pancreatic cancer than standard means of detection," said study lead author Richard Zubarik, MD, Fletcher Allen Health Care, University of Vermont. "Our results showed that potentially curative pancreatic adenocarcinoma can be identified with this screening protocol. Stage 1 pancreatic cancer is more likely to be detected by using this screening protocol than by using standard means of detection."

Methods

This prospective cohort study was conducted at the University of Vermont (UVM) and the Dartmouth-Hitchcock Medical Center (DHMC). Patients were enrolled from September 2006 to July 2009. Patients included were between the ages of 50 and 80 and had at least one first-degree relative (parent, sibling, or child) with pancreatic cancer. Enrollment was initiated at age 45 if a patient had two first-degree relatives with pancreatic cancer and at age 40 if the person had a BRCA2 mutation or Peutz-Jeghers syndrome.