CT scan of the abdomen, axial section, showing pancreatic cancer. This scan was taken after an iodine(Drug information on iodine) injection and barium opacifi cation of the stomach.ORLANDO—Identification of the diagnostic and treatment milestones that have turned some cancers into manageable chronic diseases has eluded researchers of pancreatic cancer. Diagnosis generally happens at a later stage and the survival rate is dismal even among patients for whom treatment is successful. Pancreatic cancer experts are calling for a solution that has proven to be a boon, and sometimes a bane, for other cancers: screening.
"For surgical margin-negative, lymph node-negative patients, survival is still only 30% at best. Therefore, we need to think about screening individuals at highest risk to identify high-grade precursor lesions and to intervene prior to progression. Ultimately, of course, we need to prove this saves lives," said Marcia I. Canto, MD, MHS, an associate professor of medicine and oncology at Johns Hopkins University in Baltimore.
Dr. Canto and Samir Hanash, MD, from Seattle's Fred Hutchinson Cancer Research Center, offered their insights into imaging and biomarkers that are paving the way for the possibility of widespread pancreatic cancer screening.
The Johns Hopkins experience
Pancreatic precursor lesions include intraductal papillary mucinous neoplasm (IPMN), pancreatic intraepithelial neoplasia (PanIN), and microinvasive adenocarcinoma. Screening would be targeted to an identified high-risk population (see Table).
For familial pancreatic cancer, screening should begin at an age that is 10 years younger than the youngest affected relative; for the very high risk syndromes it should begin at age 30. Surveillance intervals would depend on the baseline result, but should be every one to two years for those with normal baseline findings, Dr. Canto said.
Screening modalities at Johns Hopkins include endoscopic ultrasound (EUS) and, increasingly, MR cholangiopancreatographic imaging (MRCP), with endoscopic retrograde cholangiopancreatography (ERCP) reserved for select cases. Patients with neoplastic lesions undergo resection, with follow-up assessment by EUS at three to six months, and by EUS plus MRI at one year. Patients with negative findings undergo EUS and MRCP evaluation one year later as well.
Screening seeks to reveal pancreatic masses, including adenocarcinoma and endocrine tumors, and pancreatic cysts. Multifocal branch IPMN has frequently been identified on MRCP. EUS evaluates for pancreatic duct dilation or focal narrowing, focal polypoid pancreatic duct wall thickening, pancreatic duct echogenic material, and features of chronic pancreatitis. ERCP evaluates the ampulla (gaping, mucus), and looks for dilation, stricture, and filling defects in the pancreatic ducts, Dr. Canto said.
