Peripheral blood monocyte counts are elevated in the pre-diagnostic phase of pancreatic cancer: A population based study

Early diagnosis of pancreatic ductal adenocarcinoma (PDAC) is associated with improved outcomes. A biomarker with incremental change in the pre-diagnostic phase of the disease would be valuable for early detection. In our clinical experience, we have observed elevated peripheral blood monocyte (PBM) counts in PDAC patients at diagnosis. In this study, we aimed to compare PBM counts in PDAC cases and healthy controls at diagnosis and in the 2-year pre-diagnostic period. Using the Rochester Epidemiology Project database, we identified all patients diagnosed with PDAC between 2000 and 2015 (n = 219) and age-and gender-matched disease-free controls (n = 438). PBM counts and temporal trends were analyzed over a 24 month period before PDAC diagnosis. The groups were compared using Fisher’s exact test and t-test. At diagnosis, compared to controls PDAC cases more often had monocytosis (23% vs 8%; p