Chromium, cadmium and lead in feline mammary neoplasms

This study aimed to evaluate concentrations of heavy metals (chromium (Cr), cadmium (Cd), and lead (Pb)) in feline mammary tissues, and to correlate their concentration with clinical and pathological findings with reported impact in prognosis. In this study, a total of 62 tissue samples from 15 female cats with malignant epithelial tumors (MET; n=40 masses from 10 cats) and non-neoplastic benign lesions (H&D; n=22 masses from 5 cats) were evaluated. Tissue Cr, Cd, and Pb levels in Group MET were not significantly different from those in Group H&D (P>0.05). In Group MET, Cr in Grade 1 (n=9) tended to be higher than in Grade 2 (n=9) and Grade 3 (n=22), but it could not reach the significance (P=0.054). Also, tissue Cr levels were not significantly related to the tumor sizes (P>0.05). The highest tissue Cd level was observed in T1 (0-2 cm), which was significantly higher than in T2 (2-3 cm) (P<0.01). Also, Cd levels in T2 were lower than in T3 (> 3cm) (P<0.05). Additionally, tissue Pb levels in T3 were significantly higher than those in T2 and T1 (P<0.05). Tissue Cr levels were significantly higher in the presence of ulceration on the tumor (P<0.05), while tissue Cd and Pb levels were not significantly different (P>0.05). The findings of this study indicate that tissue Cr, Cd, and Pb concentrations are associated with clinicopathological features related to the prognosis in feline mammary tumor, which is a suitable natural model for human breast cancer research.