A test for detecting pancreatic cancer from small samples of unprocessed blood plasma at the point of care, and that can also distinguish the condition from pancreatitis, is reported in a paper published online this week in Nature Biomedical Engineering. The study suggests that the method, which is rapid, cheap and ultrasensitive, could be readily adapted for the diagnosis and monitoring of other diseases for which biomarkers in blood are known.

For investigative tests to be implemented in the clinic, they need to be fast, highly sensitive and specific, and involve minimal sample processing. However, most assays developed for the detection of cancer biomarkers present in blood require time-consuming steps.

Ye Hu and colleagues report a rapid and ultrasensitive assay (test) that is able to diagnose pancreatic cancer from as little as 0.001 ml (1 μl) of unprocessed plasma by quantifying the presence of a specific pancreatic cancer protein (ephrin type-A receptor 2). In a pilot study involving 48 healthy people, 48 patients with pancreatitis and 59 patients with stage I-III pancreatic cancer, the assay identified the pancreatic cancer patients with higher sensitivities and specificities (greater than 85%) than obtained with CA19-9, the only cancer biomarker that is routinely used in the clinic.

Although the results need to be validated in larger prospective cohort studies, the assay has the potential to improve the early detection, treatment and monitoring of pancreatic cancer and of other cancers and infections.