Regular Screening Pays Off for People at High Risk for Pancreatic Cancer
Pancreatic cancer often has a dismal prognosis, but a new study finds that screening high-risk people can catch the disease early and extend lives.
Researchers at eight U.S. medical centers found that annual screening tests paid off for patients at high risk of pancreatic cancer due to genetics. Of those diagnosed with the cancer through screening, most had it caught at an early stage, and more than 70% were still alive five years later.
That's a significant achievement, researchers said, in a disease as deadly as pancreatic cancer. Even with some treatment advances in recent years, only about 10% of patients survive for five years.
That's largely because pancreatic cancer is hard to catch early, and most people are diagnosed only after it has spread. Unlike the case with some other cancers, there is no test that can be used to routinely screen symptom-free people for pancreatic tumors.
But for more than 20 years, researchers at Johns Hopkins University have been studying ways to screen people who are at high risk. That includes individuals who carry inherited gene mutations that raise susceptibility to pancreatic cancer, and those with a strong family history of the disease.
Screening involves yearly imaging tests -- either MRI scans or endoscopic ultrasound -- to look for early signs of the cancer.
"We've been incrementally developing these data for many years," said senior researcher Dr. Michael Goggins, a professor of pancreatic cancer research at Johns Hopkins.
The latest findings were published recently in the Journal of Clinical Oncology. They confirm that regular screenings can often catch pancreatic cancer in its earliest stage. And when that happens, patients can live many years longer.
"If you're diagnosed with stage 1 pancreatic cancer through screening, the outcome is dramatically different," Goggins said.
Right now, screening for high-risk people is done in research programs at certain big medical centers. But in the future, Goggins said, "we absolutely want this to be rolled out widely."
The new findings are based, in part, on nearly 1,500 patients who enrolled in screening programs at Hopkins or one of seven other medical centers starting in 2014. Nearly half harbored gene mutations tied to pancreatic cancer. The rest carried no known mutations but had a strong family history of the disease -- most often affecting two or more first-degree relatives (parent, sibling or child), or one first-degree and at least one second-degree relative. (Second-degree relatives include aunts, uncles, grandparents, grandchildren, nieces, nephews or half-siblings).
Of that group, nine were diagnosed with pancreatic cancer through screening. Seven of those nine were stage 1, when the tumor is confined to the pancreas and can potentially be cured with surgery.
To get a picture of long-term survival, Goggins' team added findings from additional patients who'd been in prior screening studies at Hopkins dating back to 1998.
Overall, there were 19 patients with screening-detected pancreatic cancer. Most of those patients, 73%, were still alive after five years, and their median survival time was just under 10 years -- meaning half lived longer than that and half died sooner.
That stood in sharp contrast to a handful of patients diagnosed with pancreatic cancer after dropping out of regular screening: Most had advanced cancer, and their median survival was just 1.5 years.
"These outcomes with screening are a lot better than the usual," said Dr. Dana Cardin, an oncologist who treats pancreatic cancer at Vanderbilt University Medical Center in Nashville, Tenn.
Cardin, who was not involved in the research, called it important work, but also said there are challenges to making screening widely available, even to high-risk people.
There are the logistics: Endoscopic ultrasound, for example, is not done everywhere, Cardin noted, and it takes expertise to interpret the images taken during screening. For patients, she said, years of annual tests can be onerous, with both "cost issues and anxiety issues."
There's also a broader question of cost-effectiveness, Cardin pointed out. Pancreatic cancer is relatively rare, accounting for about 3% of all cancers in the United States, according to the American Cancer Society. And even in this high-risk study group, the number of cancers detected was small -- at a rate of 5 per 1,000 patients each year.
In addition, screening itself is not without risks. In this study, there were five patients who underwent surgery after imaging showed suspicious lesions, only to be told the growths were not cancerous.
That surgery, Goggins said, "is not trivial."
The issues of who to screen for pancreatic cancer, how to do it and when are "really challenging," Cardin said.
"That's why we need rigorous research like this," she added.
As for people at average risk of pancreatic cancer, there is no test available for routine screening. Any such test, Cardin noted, would have to be highly accurate, and simple and cheap enough to be done outside of expert medical centers.
The Pancreatic Cancer Action Network has resources for patients.
SOURCES: Michael Goggins, MD, professor, pancreatic cancer research, and director, Pancreatic Cancer Early Detection Laboratory, Johns Hopkins Medicine, Baltimore; Dana B. Cardin, MD, associate professor, medicine, Vanderbilt University Medical Center, Nashville, Tenn.; Journal of Clinical Oncology, June 15, 2022, online