What to do (and not do) about pancreatic cysts
Date: July 1, 2011
If you’re a specialist in pancreatic cysts, three facts currently drive your work: The number of patients with cysts has massively increased of late. The growths can vary pathologically, making diagnosis dicey. They differ in potential for malignancy. Oh, there’s another: One type of cyst—the intraductal papillary mucinous neoplasm, or IPMN—is so relatively new to the field that fine points of diagnosis and treatment are still being worked out.
“All this has convinced us of the need for a specialty clinic,” says gastroenterologist Anne Marie Lennon, “with access to the disciplines that a large academic institution can provide.” So the new Johns Hopkins Multidisciplinary Pancreatic Cyst Clinic, which Lennon directs, pools the expertise of dedicated pancreatic endoscopists, pancreatic surgeons and specialists in pancreatic cyst pathology. Also included are experts in CT and in MRI imaging of the cysts.
We asked Lennon to elaborate.
Q:Most pancreatic cysts are “pseudocysts” and not so difficult to diagnose. The rest can be harder, you say?
A: Yes. We need to distinguish which are benign and don’t need follow-up unless they’re symptomatic, from the smaller number that have a potential to develop cancer. We’re particularly interested in IPMNs.
A: Several reasons. As a field, we’re still on a learning curve with IPMNs. We know they can affect the main duct of the pancreas, the branch duct or both. The location is a concern. IPMNs in the main duct have up to a 70 percent risk of adenocarcinoma and require surgery. The branch duct, however, is more of a problem because the cancer risk, while it exists, is lower. If the cyst is in the tail of the pancreas and looks suspicious, we counsel having it removed via a distal pancreatectomy, a low-risk procedure. If, however, it arises in the head of the pancreas, the required surgery is a Whipple. And though Hopkins statistics for that are superb—less than 2 percent mortality—we know that particular surgery isn’t something you’d take on lightly, especially for the high proportion of older patients with these cysts.
Q:What might help?
A: Two things. We need more information about which cysts harbor or may develop malignancy. So we’re working with a group of basic scientists here at Hopkins to find a biomarker to tell us who should go to surgery. The group includes molecular biologist Bert Vogelstein, who’s known for his work on sentinel colorectal cancer genes. Also, we’ve begun a large, prospective pancreatic cyst study [see box] that should give us answers about disease course and best imaging practices.
410-933-7262 to refer a patient.
Pancreatic cyst study now enrolling patients
Johns Hopkins researchers are conducting a study to discover the long-term fate of pancreatic cysts and to improve treatment and diagnosis. They’re enrolling patients who have any type of pancreatic cyst. Participants receive a high-resolution CT/MRI and endoscopic ultrasound; then they’re followed periodically with a CT or MRI. As part of the study, pancreatic cyst fluid and blood will be collected for biomarker analysis. Details: Hilary Cosby, 410-502-2892 or firstname.lastname@example.org
Deciding when to operate
Only in the late 1980s did physicians begin discovering the pancreatic cysts known as intraductal papillary mucinous neoplasms, or IPMNs, and then only by accident: Patients complaining of abdominal pain would undergo CT scans that would pick up the growths, which often were unrelated to the patient’s symptoms.
That awareness created a further problem: How should physicians treat IPMNs, if at all?
Because such a small percentage will progress to cancer, determining whether to operate can be challenging, says Christopher Wolfgang, director of Johns Hopkins’ Pancreatic Surgery Section: “If you take 100 of these patients, maybe three or four will develop cancer over time. Since the mortality of a major pancreatic operation is about two percent to three percent, if we operated on everyone with a pancreatic cyst, statistically as many people would die from the procedure as would be saved.”
Therefore, selecting patients who will most benefit from the surgery—that is the ones whose risk of cancer exceeds the risk of the operation—is critical. The key to a good outcome is being cared for by a group of clinicians who have a thorough understanding of the complex treatment plan for managing IPMNs. For instance, patients with a main-duct IPMN are clear candidates for surgery based on a high risk of malignancy. On the other hand, patients with a side-branch IPMN have a much lower risk of developing a cancer and may not require an operation, provided they meet certain criteria.
“What’s rewarding,” Wolfgang says, “is that if we select the appropriate patient and take the cyst out, we can offer 100 percent prevention and cure.”