Simple Blood Test Recommended for Pancreatic Cancer Patients

A new and largest-of-its-kind study has found that few pancreatic cancer (PC) patients (in the US less than 1 in 5) undergo a key tumor-marker blood test and concluded that all PC patients should at diagnosis take this widely available test, which was found to be especially important for early-stage patients.

The study, by Mayo Clinic (Rochester, MN, USA) clinical researchers, showed that taking the test for tumor marker CA 19-9 at PC diagnosis can help predict whether patients are likely to have a better or worse outcome than average and help guide treatment accordingly. People who tested positive for elevated CA 19-9 levels tend to do worse than others, but if they are candidates for surgery and have chemotherapy prior to surgery, this personalized treatment sequence eliminates the negative effect.

The findings were presented at the Western Surgical Association 2015 Annual Meeting (Napa Valley, CA, USA; November 7–10), with first author John Bergquist, MD, Mayo Clinic resident physician and researcher, and senior author Mark Truty, MD, gastrointestinal surgical oncologist, Mayo Clinic.

“This is another argument for giving chemotherapy before surgery in all PC patients and ending the old practice of surgery followed by chemo,” said Dr. Truty, “The study answers an important clinical question and applies to every PC patient being considered for surgery.”

The study, which used the National Cancer Data Base (NCDB), is the first on the subject based on national data and is the largest of its kind. The researchers analyzed outcomes for 97,000 patients to study the impact of CA 19-9, a marker associated with several cancers and can be measured in the blood of most people (10% do not produce it). PC patients who did not secrete CA 19-9 were also studied.

PC patients whose blood showed higher-than-normal CA 19-9 levels tended to have worse outcomes than others at the same stage of cancer. Surprisingly, the elevated tumor marker’s negative effect on survival was most pronounced in patients diagnosed at an early stage.

“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,” said Dr. Truty.

Another key finding was that only 19% of PC patients in the US have their CA 19-9 checked at diagnosis, far fewer than anticipated. The test has been standard for PC patients at Mayo Clinic for years. 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.

Historically, only about 7% of PC patients have lived at least 5 years after diagnosis. Advances such as the CA 19-9 test and improved chemotherapy, radiation, and surgical techniques are improving survival odds. “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 PC treatment,” said Dr. Truty, noting that the test currently costs about USD 170, “Further, patients with any elevation of CA 19-9 should be considered for preoperative chemotherapy to eliminate this risk.”

Related Links:
Mayo Clinic
Western Surgical Association 2015 Annual Meeting
Program & Abstracts