Evaluation of tumor markers carcinoembryonic antigen, cytokeratin 19 fragment and cancer-associated antigen 72-4 in neoplastic and non-neoplastic canine effusions differentiation

The concentration of tumor markers in body fluids can be used for diagnosis and prognosis of patients. This study aimed to investigate the performance of tumor markers cytokeratin 19 fragment (CYFRA 211), cancer-associated antigen 72-4 (CA 72-4) and carcinoembryonic antigen (CEA) in the neoplastic and non-neoplastic canine effusions. In thirty-two neoplastic (n=16) and non-neoplastic (n=16) samples of canine thoracic or abdominal effusions, tumor markers were measured. Significant statistical difference was found only for the CYFRA 21-1 marker. The levels were significantly higher for the neoplastic group. The lack of significance between groups for markers CA 72-4 and CEA can be explained by the presence of other diseases in the non-neoplastic group, causing elevated levels of these markers. This study concludes that CYFRA 21-1 performed well, showing good sensitivity, specificity and accuracy in the diagnosis of neoplastic effusions in dogs. However, further investigations are necessary in patients with malignancy as those with benign effusions.