| News from the American College of Surgeons For Release: February 22, 2008, 9:00 am (CT) |
Contact: Sally Garneski 312-202-5409 or |
NEW SCORING SYSTEM HELPS PREDICT SURVIVAL IN PATIENTS
WITH PANCREATIC NEUROENDOCRINE TUMORS
Researchers analyze 20 years of data from National Cancer Database
to develop reliable predictions for this tumor type
CHICAGO: A diagnosis of pancreatic cancer can be dire, but for a rare type of cancer known as pancreatic neuroendocrine tumors (PNET), survival rates are better than might be expected. “This is a less common form of pancreatic cancer, but it’s particularly interesting because it has a favorable prognosis—much more favorable than we typically think about for pancreatic adenocarcinoma, a more common variety,” according to Karl Y. Bilimoria, MD, American College of Surgeons Research Fellow, Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL and lead author of a new study on PNETs.
In a study just released in the Annals of Surgery, Dr. Bilimoria and associates studied this rare yet treatable tumor in order to develop a new scoring system to predict prognosis. Such scoring systems are used to predict outcomes, guide treatment decisions, and help classify patients into different groups for enrollment in clinical trials. “The goal was to come up with a simple score that physicians could easily use as part of their armentarium to manage PNETs,” Dr. Bilimoria said.
To develop the scoring system, the research group analyzed 20 years of data from the National Cancer Data Base (NCDB), a joint program of the American College of Surgeons Commission on Cancer and the American Cancer Society. PNETs account for about 3 to 5 percent of pancreatic tumors, and “generally, they are much less aggressive tumors,” Dr. Bilimoria explained. Dr. Bilimoria and his colleagues used NCDB data to help determine which factors affect survival in patients with PNETs. Studying this tumor is particularly important as studies have shown a 200 percent to 300 percent increase in PNETs over the past 16 years: “the incidence is probably increasing because more people are getting CT scans more often—it’s often an incidental finding discovered on a CT scan performed for another reason,” Dr. Bilimoria explained.
The researchers reviewed data on a large population of PNET patients (nearly 4,000 patients who underwent a surgical procedure from 1985 to 2004). “The large number of patients provided us with the ability to discriminate between the more and less important prognostic factors,” Dr. Bilimoria said.
The research group developed a final scoring system that included 3 levels (1, 2, and 3) based on a summation of three predictive factors: age (<55, 55-75, or >75); tumor grade (a factor based on the aggressiveness of the tumor cells); and distant metastases (none, liver, or other). Each factor was given a score, and the three scores were summed together to create a raw score. The raw score was then translated into a “prognostic score,” which provides an estimate of the five-year survival rate and can also be used to help guide treatment decisions.
As an example, a patient under 55 years of age (0 points) with a low-grade tumor (0 points) and no metastases (1 point) would have a raw score of 0. This raw score translates into a prognostic score of 1 (on a scale of 1 to 3) which has a five-year survival of 77 percent. Conversely, a prognostic score of 3 would be associated with a 5-year survival rate of 36 percent.
Is this type of survival good or bad news for patients? “For adenocarcinoma, the same patient would have a 15 to 20 percent chance of survival at five years,” Dr. Bilimoria replied. “With these tumors, even people who have distant metastases at the time of presentation can have an excellent prognosis and may be surgical candidates.”
“There are three things that this new PNET scoring system really helps us with,” Dr. Bilimoria concluded. “First, it gives patients information about their prognosis that’s reliable and is based on a broad generalizable experience, across the country. Second, it gives you an idea of which treatments to choose. If they have a very aggressive tumor, we may think about getting them into a clinical trial or using an additional form of therapy, such as chemotherapy. And finally, it helps stratify patients once enrolled in a clinical trial.”
The study results will be published in the March 2008 issue of the Annals of Surgery.
In addition to Dr. Bilimoria, contributing authors include Mark S. Talamonti, MD, FACS (Northwestern University); James S. Tomlinson, MD (Evanston Northwestern Healthcare); Andrew K. Stewart, MA (American College of Surgeons Commission on Cancer); David P. Winchester, MD, FACS (American College of Surgeons); Clifford Y. Ko, MD, MS, Mshs, FACS, (University of California, Los Angeles (UCLA) and VA Greater Los Angeles Healthcare System); and David J. Bentrem, MD (Northwestern University).
The study was supported by the American College of Surgeons Clinical Scholars in Residence program and the Department of Surgery, Feinberg School of Medicine, Northwestern University.
The National Cancer Database is recognized as the largest clinical registry in the world. It is a nationwide oncology outcomes database for more than 1,430 Commission-approved cancer programs in the United States and Puerto Rico, and captures approximately 70 percent of all new invasive cancers diagnosed annually.
About Annals of Surgery: An Affiliated Journal of the American Surgical Association.
The world's most highly referenced surgery journal, Annals of Surgery (www.annalsofsurgery.com), a Lippincott Williams & Wilkins journal, provides the international medical community with information on significant contributions to the advancement of surgical science and practice. Surgeons look to Annals of Surgery first for innovations in practice and technique. Special editorial features include "Advances in Surgical Technique", which provides up-to-the-minute coverage of current clinical issues, and monthly review articles that cover the most current practice concerns.
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Online February 22, 2008