Trace element profiles in canine neoplastic disease.

Trace elements are essential for physiological processes and have also been associated with tumour development, progression and prognosis in human medicine. This study aimed to characterize the plasma mineral profile of dogs with tumours and explore associations between elements and clinical findings. A total of 164 dogs with tumours (mammary, mast cell tumour, soft tissue sarcoma, intracranial, lymphoma, and hepatic tumour) and 40 controls were included. Plasma samples were analysed for As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, and Zn by mass spectrometry. Clinical findings and biochemical alterations were recorded. Compared to controls, dogs with tumours had higher concentrations of Cu (P < 0.001), Mn (P < 0.01), Ni (P < 0.001), Pb (P < 0.05), Se (P < 0.001), and Zn (P < 0.001). Element profiles differed by tumour type, with changes being particularly evident for hepatic tumours. Higher Cu and Mn concentrations and lower Se levels were associated with the presence of diverse clinical symptoms and distant metastasis. The study findings revealed different plasma trace element profiles in dogs with tumours and in controls, with variations linked to tumour type and clinical features. The findings suggest trace elements could be used as biomarkers for clinical staging or prognosis in canine tumours. Based on their informativeness in this study, Cu, Mn, Ni, Se, and Zn are recommended for inclusion in a core mineral panel for future research.