Screening for pancreatic cancer was until very recently a fool’s errand. This cancer is an order of magnitude less common than the three big killers — breast, colon and lung cancer — and previously there was no evidence that picking up an early pancreatic cancer led to an improved outcome — the gold standard for a screening test.
There are families in whom the incidence of pancreatic cancer is much higher than the general population. Groups in Germany, Spain and the Netherlands identified several hundred people who because of known genetic mutations were at much higher risk than average of developing pancreatic cancer. They included so-called familiar pancreatic cancer syndrome clusterings, people with BRCA-1 and -2 mutations and two other less common mutations as well. All of those studied had a risk of pancreatic cancer orders of magnitude higher than average, so screening was likely to pick up more cases strictly on the basis of percentages. During the period of observation — several years — over twenty new cases of pancreatic cancer were found in the 400 or so patients being screened, for an astronomical incidence of 5%. The five-year survival of the patients so diagnosed was 25%, or about five times higher than that seen in people diagnosed because they have symptoms.
Dr. Stark weighs in: the challenge to developing a screening test for pancreatic cancer was twofold. First you have to identify a population at enhanced risk to justify the expense in going after a needle in a haystack, and then you have to show that finding cases in asymptomatic individuals leads to a better outcome. The authors have met these objectives. They used only imaging studies in their screening. It would have been interesting had they used in addition the CA 19-9 blood test, which is elevated in the majority of people with symptomatic pancreatic cancer. Adding this test to the imaging studies might have enhanced the sensitivity of the screening event and would have demonstrated whether using this test — much cheaper and easier than x-ray studies — has any role to play in screening.
The study results are published in the Journal of Clinical Oncology in June, 2016. Click here for the abstract. Dr. Stark can send you the full article if requested. It is currently available at that link but may not remain so.