A simple biomarker scoring matrix for early gastric cancer detection

Gastric cancer (GC) is a major cause of death in many parts of the world. While 90% of early GC is curable by resection, only about 5% of patients diagnosed in the late stages survive beyond five years. This provides strong impetus to push for early GC detection through the use of non-invasive biomarkers, before metastatic complications arise. It is also of strong medical interest to identify patients of the diffuse subtype at the earliest time possible, since the disease variant progresses very rapidly and is associated with much higher mortality rate. In this study, we compared quantitatively the gastric fluid proteome of 70 GC patients to 17 individuals with benign gastritis in search of potential biomarkers that aid in GC diagnosis, prognosis and subtype stratification. We report that as much as half of the gastric fluid proteome is subject to regulation in diseased states, and propose a simple biomarker panel scoring matrix for early GC detection with diagnostic sensitivity of 95.7%. We also demonstrate as proof-of-concept that a digitised record generated with SWATH-MS based on 380 protein abundance signatures from the gastric fluid could segregate patients with diffuse-type GC.