Therapeutic Endoscopy for Pancreatic Disease
Frank Gress, MD, is Clinical Division Chief and Chief of Interventional Endoscopy in the Division of Digestive Disease and Liver Disease. An expert in therapeutic endoscopy, Dr. Gress specializes in performing minimally invasive procedures to diagnose and treat disorders of the gastrointestinal tract, bile ducts, and pancreas. He also performs clinical research on innovative technologies to improve the endoscopic diagnosis and management of pancreatic diseases.
In the following interview, Dr. Gress explains the uses of therapeutic endoscopy in treating patients with pancreatic disease and he shares information about a very important technological advance at the Pancreas Center.
What is your background and training?
Dr. Gress: I completed my medical school training at Mt. Sinai School of Medicine, my residency in internal medicine at Montefiore Medical Center in the Bronx, and my gastroenterology and hepatology fellowship at the SUNY Downstate Medical Center affiliated program with the Brooklyn Hospital Center, and Methodist Hospital. After my fellowship, I decided to become a therapeutic endoscopist, which required another year of training. I received a scholarship from the American Society of Gastrointestinal Endoscopy which allowed me to train at Indiana University Medical Center, which is well known for its therapeutic endoscopy (TE) unit. I trained in endoscopic retrograde cholangiopancreatography (ERCP), endoscopic ultrasound (EUS), and endoscopic lasers, after which I remained on the faculty for four years. Beginning in 1997 I joined the faculty at Winthrop University Hospital and SUNY Stony Brook where I was director of endoscopy. I was recruited to the faculty at Duke University Medical Center in 2003 as a member of the pancreatobiliary service. I was also clinical chief of the GI division at the Durham VA Medical Center. I returned to New York in 2007 to be division chief of the division of gastroenterology and hepatology at SUNY Downstate Medical Center until I joined the faculty at Columbia in the fall of 2013.
Why did you choose to focus on pancreatic disease?
Dr. Gress: I was intrigued by how ERCP and EUS could impact patients’ outcomes and quality of life for pancreatic diseases such as chronic pancreatitis, pancreatic cysts and pancreatic cancer. That interest evolved into wider interest in pancreatic disease. I am especially interested in diagnosing and treating pancreatic cancer at earlier stages and in helping patients with chronic pancreatitis to live a more normal life.
What are the benefits of ERCP and EUS?
Dr. Gress: ERCP is a tool used by therapeutic endoscopists to evaluate the pancreatic and bile ducts. It lets us see the size of the ducts, their contour and shape, whether there is anything inside the duct, and it lets us view the ampulla, which is the opening into the duodenum. We can now insert an optic light into the scope using a device called SPY, which lets us look into the pancreatic duct or bile duct and take a biopsy to make a diagnosis. In addition to its value in diagnosing a problem, ERCP can also be used to treat it. During ERCP we can sample suspicious areas inside or outside the bile or pancreatic duct, and we can remove pancreatic or bile duct stones. We can also treat strictures by placing a stent or a drain tube, and we can manage difficult-to-treat disorders of the bile duct including Sphincter of Oddi dysfunction using specialized equipment.
EUS is also used for both diagnostic and therapeutic purposes. The ultrasound technology is situated on the tip of the endoscope which lets us look through the wall of the GI tract and beyond the wall, particularly in the bile duct, pancreatic duct, and liver. EUS provides high definition fine detail of the pancreas and surrounding structures, including the lymph nodes. If someone has abnormal findings on an MRI or a CT scan, EUS can provide a much closer look at the abnormality. We can also attach a special needle in order to sample lesions. This is called fine needle aspiration, or FNA, and it is very accurate for diagnosing suspicious lesions. We can use it to sample many types of lesions, such as masses in the pancreas, bile ducts and even kidney , adrenal masses, lung masses and others, and it is a great tool for staging cancers.
How is EUS used to treat patients with pancreatic disease?
Dr. Gress: Therapeutic EUS is an evolving field. One example of a new application is EUS guided celiac plexus block, which is a procedure that controls pain related to pancreatic cancer or chronic pancreatitis. More than 75% of patients find pain relief from this procedure, which is essentially a pain block. Another therapeutic application is the drainage of pseudocysts that can cause pain in pancreatitis, or to drain the bile duct if it can’t be drained by ERCP.
Can you summarize the difference between ERCP and EUS?
Dr. Gress: ERCP is more invasive as we actually go into the duct, and requires contrast dye and fluoroscopy. EUS is more of an ultrasound imaging tool so it is less invasive; we look at the pancreas from the outside looking in, while in ERCP we look deep inside the pancreatic and bile ducts.
Please tell us about confocal laser endomicroscopy, or CLE.
Dr. Gress: CLE is a device that allows us to view cells in high definition, much like you would see under a microscope, but doing so while inside the body. Some studies suggest that it may replace the need for biopsies. This technology is very exciting because it allows us to detect early cancer and changes suggestive of early cancer such as dysplasia at the cellular level. CLE can be put through our scope into the bile duct or pancreatic duct and used to see any abnormal tissue in the duct lining. It can also be used during EUS to see inside pancreatic cysts, so we can tell whether they warrant further treatment.
Are you using CLE in the Pancreas Center?
Dr. Gress: Columbia is one of only two centers in New York that has CLE – it is a very innovative technology in the U.S. and is just beginning to be studied in more detail. We are beginning to use CLE in the pancreas and pancreatic cysts, and insurance does cover it.
Which patients will benefit from the use of CLE?
Dr. Gress: CLE may be useful for patients with chronic pancreatitis, pancreatic cysts, with pancreatic and bile duct strictures, and patients with family history of pancreatic cancer or intraductal papillary mucinous neoplasm (IPMN), an early form of pancreatic cancer). In the case of pancreatic cysts, we have not been able to predict with very high accuracy if a cyst is malignant or not, so patients have had to come for regular followup in order to be vigilant about any potential cancers. The ability to characterize cells with CLE is a game changer. We can place it on a probe (probe-based CLE, or PCLE) and perform what is called an optical biopsy – determine whether cells are malignant or not by looking at them rather than extracting samples. It is also very helpful for targeting areas to biopsy; for now we are still taking tissue biopsies and using CLE to validate the findings, but in the future, we hope to be able to make determinations without taking tissue.
Can CLE be used to treat patients with other types of cancer?
Physicians at Columbia are using CLE in patients with Barrett’s Esophagus, and it is used elsewhere for gastric lesions (to check for stomach cancer).
Can you describe your research on CLE?
As we mentioned above, we are collecting patient data in our registry and comparing the data to the images collected during probe-based CLE procedures. Because this technology is so new to us, part of our research is to verify that the images seen during the procedure correlate with the tissue pathology samples. This work will allow us to independently verify the positive outcomes that others have experienced with PCLE.
A second part of our research entails the use of EUS-guided fine needle aspiration (FNA) CLE, also known as nCLE, in patients with pancreatic cysts. This is a multicenter study (Columbia is one of three sites) in which we insert an EUS needle into the pancreatic cyst, put the CLE probe through the needle, and examine the cells lining the walls of cysts. We will soon be expanding this to the lymph nodes as well. We are hoping that nCLE will be able to provide high detailed and accurate characterization of pancreatic cysts such that pancreatic cysts can be more accurately differentiated into benign and malignant cysts.