Only 1 in 5 U.S. Patients With Pancreatic Cancer Gets Key Blood Test at Diagnosis
Only 1 in 5 patients with pancreatic cancer in the United States receives a widely available, inexpensive blood test at diagnosis that can help predict relative outcome (compared to others with the same disease stage) and guide treatment accordingly, a Mayo Clinic study showed. People who test positive for elevated levels of a particular tumor marker tend to do worse than others, but if they are candidates for surgery and have neoadjuvant chemotherapy, this treatment sequence eliminates the elevated biomarker's negative effect, researchers found. The findings will be presented at the Western Surgical Association Annual Meeting, November 7–10, 2015, in Napa, California.
“This is another argument for giving chemotherapy before surgery in all pancreatic cancer patients and ending the old practice of surgery followed by chemotherapy,” said Mark Truty, MD, a gastrointestinal surgical oncologist at Mayo Clinic. “The study answers an important clinical question and applies to every pancreatic cancer patient being considered for surgery.”
Study Findings
The Mayo study, which used the National Cancer Data Base, is the first on the subject based on national data and is the largest of its kind, Dr. Truty said.
Analyzing outcomes for 97,000 patients, the researchers studied the impact of the tumor marker CA 19-9, which is associated with several cancers, including pancreatic cancer, and can be measured in the blood of most people (although 10% do not produce it). Patients with pancreatic cancer who didn't secrete CA 19-9 were also studied.
Pancreatic cancer patients whose blood showed higher-than-normal CA 19-9 levels tended to have worse outcomes than others at the same stage of cancer, the study found. Surprisingly, the elevated tumor marker's negative effect on survival was most pronounced in patients diagnosed at an early stage, the researchers wrote.
“When we looked at how these patients did after surgical removal of their cancers, the only treatment sequence that completely eliminated the increased risk posed by CA 19-9 elevation was chemotherapy followed by surgical removal of the tumor,” Dr. Truty explained.
Another key finding was that only 19% of pancreatic cancer patients nationally have their CA 19-9 checked at diagnosis—far fewer than anticipated. Failing to test for and address elevated CA 19-9 means that many patients with above-normal levels may undergo significant surgeries that may not be as beneficial long term as anticipated, Dr. Truty said.
“Our conclusion is that every patient should have a CA 19-9 test at diagnosis. This is a simple, cheap, and widely available test that allows personalization of pancreatic cancer treatment,” Dr. Truty concluded, noting that the test costs about $170—pennies on the dollar relative to the overall cost of a patient's cancer care. “Further, patients with any elevation of CA 19-9 should be considered for preoperative chemotherapy to eliminate this risk.”
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
