DR-70 (fibrinogen-fibrin degradation products) as a prognostic biomarker in dogs with neoplasms

Abstract

Fibrinogen-fibrin degradation products (DR-70) are derived from tumor cells or metastases. Our previous study reported the diagnostic values in dogs with tumors, but no research has yet to be conducted to establish DR-70 as a prognostic marker. Herein, we investigated changes in DR-70 concentrations and disease courses in dogs with tumors. Overall survival time (OST) analysis was performed in 195 dogs with tumors, stratified with a recommended cut-off (1.514 µg/mL). Continual DR-70 measurements were performed during the medical interventions of 27 dogs with neoplasms. Clinical conditions and medical records were retrospectively reviewed. According to a cut-off value, dogs with plasma DR-70 concentrations above 1.514 µg/mL had shorter survival rates than those with concentrations below this threshold. In cases with complete or partial remission in response to treatment, the DR-70 concentration was decreased compared with that at the first visit, whereas it was increased in patients with disease progression. Our study suggested that changes in DR-70 concentration can be used as a prognostic biomarker for canine neoplasms. Furthermore, increased plasma DR-70 levels might be associated with shorter survival, and DR-70 concentrations may reflect responses to medical intervention.

Keywords: DR-70; fibrinogen-fibrin degradation products; prognostic biomarker; tumor monitoring.

Figure 1.

Kaplan-Meier Survival curve for dogs with tumors divided by a cut-off DR-70 value of 1.514 µg/mL. Dogs with lower DR-70 concentrations (<1.514 µg/mL) survived significantly longer (p = 0.0091) than did dogs with higher DR-70 values. Survival time represents the time from diagnosis to death or euthanasia. Statistical analysis was calculated by log-rank (Mantel-Cox) test. **p < 0.01.

Figure 2.

DR-70 concentrations (μg/mL) highly correlated to the tumor progression in dogs with multicentric B-cell lymphoma. (A–K) were the cases #1 to #11, respectively. CR, complete response PR, partial response; SD, stable disease; PD, progress disease.

Figure 3.

DR-70 concentrations (μg/mL) highly correlated to clinical responses to treatments in dogs with mast cell tumor. (A–J) represented the cases #12 to #21, respectively. CR, complete response PR, partial response; SD, stable disease; PD, progress disease.

Figure 4.

DR-70 concentrations (μg/mL) incorporated with the clinical responses in dogs with tumors. Alterations of DR-70 concentrations in dogs with (A) transitional cell carcinoma (case #22), (B) transitional cell carcinoma (case #23), (C) nasal adenocarcinoma (case #24), (D) prostatic adenocarcinoma (case #25), (E) squamous cell carcinoma (case #26), and (F) mammary gland tumor (case #27). CR, complete response PR, partial response; SD, stable disease; PD, progress disease.