Near-infrared Imaging System Shows Promise to Diagnose Pancreatic Cancer Early
FDA approves test in humans using an OCT probe small enough to be inserted into pancreas through a biopsy needle:
earlier study reports using targeted endoscopic ultrasound for early detection of pancreatic cancer
A: Photograph of the OCT instrument and imaging probe;
Bs: Gross appearance and magnified OCT image of the
malignant mucinous cystic neoplasmsm (MCN);
Cs: Gross appearance and magnified OCT image of the benign serous cystic adenoma (SCA). MCNs
have large cavities, filled with a mucinous fluid that scatters light (see yellow arrow), while SCAs have a honeycomb structure of smaller
cavities separated by a tiny septae (see red arrow). The SCA fluid is optically transparent and does not scatter light. OCT scale bar: 500 μm.
Images: Dr. Nicusor Iftimia, Physical Sciences Inc. and Dr. William Brugge, Massachusetts General
Hospital.
Aug. 17, 2011 Pancreatic cancer is among the most deadly, especially if not discovered early. Researchers from four
Boston-area institutions think they have found something that may provide an edge in early diagnosis - optical coherence tomography (OCT), a
high resolution optical imaging technique that works by bouncing near-infrared laser light off biological tissue.
The team led by Nicusor Iftimia from Physical Sciences, Inc., has proven that OCT can reliably distinguish between
pancreatic cysts that are low-risk and those that are high-risk for becoming malignant. Other optical techniques often fail to provide images
that are clear enough for doctors to differentiate between the two types.
To test the diagnostic potential of OCT imaging, researchers used the technique to examine surgically removed pancreatic
tissue samples from patients with cystic lesions. By identifying unique features of the high-risk cysts that appeared in the OCT scans, the
team developed a set of visual criteria to differentiate between high and low risk cysts.
They then tested the criteria by comparing OCT diagnoses to those obtained by examining thin slices of the pancreatic
tissue under a microscope.
Their results, described in the August issue of the Optical Society's (OSA) open-access journal Biomedical Optics
Express, showed that OCT allowed clinicians to reliably differentiate between low-risk and high-risk cysts with a success rate close to that
achieved by microscope-assisted examinations of slices of the same samples.
Future studies by the research team will focus on improving imaging resolution to further differentiate between solid
lesions and autoimmune pancreatitis, and test this technology in vivo.
They recently received FDA approval for testing this technology in human patients by using an OCT probe small enough to
be inserted into the pancreas through a biopsy needle, which will be guided into suspect masses in the pancreas by endoscopic ultrasound
imaging.
Urgent Need to Diagnose Pancreatic Cancer Early
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.
A pilot clinical study is planned to start within the next couple of months. If in vivo data will prove reliable
differentiation between the two types of cysts, a study in a larger number of patients will be planned, contingent on NIH funding and FDA
approval.
About Biomedical Optics Express
Biomedical Optics Express is OSA's principal outlet for serving the biomedical optics community with rapid, open-access,
peer-reviewed papers related to optics, photonics and imaging in the life sciences. It is published by the Optical Society and edited by
Joseph A. Izatt of Duke University. Biomedical Optics Express is an open-access journal and is available at no cost to readers online at
http://www.OpticsInfoBase.org/BOE.
About OSA
Uniting more than 106,000 professionals from 134 countries, the Optical Society (OSA) brings together the global optics
community through its programs and initiatives. For more information, visit http://www.osa.org.
Another study reports use of a tumor marker and targeted endoscopic ultrasound for early detection of pancreatic cancer
Researchers from New England reported in a study released in July 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 appeared in the July issue of GIE: Gastrointestinal Endoscopy, the monthly peer-reviewed scientific
journal of the American Society for Gastrointestinal Endoscopy (ASGE).
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 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, said
study lead author Richard Zubarik, MD, Fletcher Allen Health Care, University of Vermont.
The results conclude that potentially curative pancreatic cancer can be identified with CA 19-9 and targeted EUS. Stage 1
pancreatic cancer is more likely to be detected by using this screening protocol than by using standard means of detection.
Potential advantages include acceptable rates of disease diagnosis and exclusion as well as acceptable costs (cost to
detect 1 pancreatic neoplasia was $8,431, while the cost to detect 1 pancreatic cancer was $41,133).
In particular, the patient with pancreatic cancer detected with this screening protocol is alive without evidence of
recurrence three years after surgical resection and is the longest survivor of pancreatic cancer detected in a published screening protocol.
Also, evidence of pancreatic cancer did not develop in subjects with negative screening studies, at least in short-term follow-up.
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