Increased plasma DR‐70 (fibrinogen‐fibrin degradation products) concentrations as a diagnostic biomarker in dogs with neoplasms

BACKGROUND: Tumor biomarkers have used widely in clinical oncology in human medicine. Only a few studies have evaluated the clinical utility of tumor biomarkers for veterinary medicine. A test for fibrinogen and fibrin degradation products (DR‐70) has been proposed as an ideal biomarker for tumors in humans. The clinical value of DR‐70 for veterinary medicine however has yet to be determined. OBJECTIVES: Investigate the diagnostic value of DR‐70 concentrations by comparing them between healthy dogs and dogs with tumors. ANIMALS: Two hundred sixty‐three dogs with different types of tumors were included. Sixty healthy dogs also were recruited for comparison. METHODS: The DR‐70 concentrations were measured in all recruited individuals by ELISA. Clinical conditions were categorized based on histopathology, cytology, ultrasound examination, radiology, clinical findings, and a combination of these tests. RESULTS: The median concentration of DR‐70 was 2.130 ± 0.868 μg/mL in dogs with tumors, which was significantly higher than in healthy dogs (1.202 ± 0.610 μg/mL; P < .0001). With a cut‐off of 1.514 μg/mL, the sensitivity and specificity of DR‐70 were 84.03% and 78.33%, respectively. The area under curve was 0.883. The DR‐70 concentration can be an effective tumor biomarker in veterinary medicine. CONCLUSIONS AND CLINICAL IMPORTANCE: Increased DR‐70 concentrations were not affected by tumor type, sex, age, or body weight. However, in dogs with metastatic mast cell tumors and oral malignant melanoma, DR‐70 concentrations were significantly increased. Additional studies, including more dogs with nonneoplastic diseases, are needed to further evaluate the usefulness of DR‐70 as a tumor biomarker.