The Prognostic and Predictive Value of DR-70 Immunoassay, A Novel Fibrin-Associated Biomarker, in Patients with Advanced Gastrointestinal Cancers

Abstract

Aim: DR -70 is a newly developed immunoassay that detects fibrin degradation products in blood. We aimed to evaluate ability of DR -70 in monitoring treatment response in advanced gastrointestinal (GI) cancers. Materials and Methods: We prospectively enrolled patients with advanced GI cancers treated with different lines of systemic therapies. Imaging studies, DR -70 and conventional tumor markers [carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19-9] were analyzed at baseline and on the third month of treatment. Results: A total of 142 patients diagnosed with colorectal (52.1%), esophago-gastric (32.4%) and pancreaticobiliary cancer (15.5%) were enrolled. Most patients were getting first -line treatment (56.3%). Second blood sampling was performed in 57% of patients. Among patients with esophagogastric cancer, DR -70 response correlated well with treatment response (p=0.007) and low baseline DR -70 level was significantly associated with longer overall survival (p=0.02). There was a positive but weak correlation between pre-treatment DR -70 and CEA levels (p=0.03, r=0.244) in patients with colorectal cancer, while a moderate positive correlation was present between pre-treatment DR -70 and CA 19-9 levels in esophagogastric and pancreaticobiliary cancers (p=0.01, r=0.402 and p=0.04, r=0.515, respectively). More than 25% reduction in DR -70 concentration was associated with better overall and progression -free survival. Conclusion: DR -70 is a strong predictor of treatment response and survival, particularly in esophago-gastric cancer.