Clinical significance of serum copper/zinc ratio in diagnosis for recurrent breast cancer

To evaluate the ability of Cu/Zn ratio in diagnosis for recurrent breast cancer, 40 patients radically treated for breast carcinoma were studied. Of them, 13 cases were with recurrent breast cancer, 27 patients were free-recurrent. Serum zinc and copper were determined by atomic absorption spectrophotometry, meanwhile serum carcinoembryonic antigen (CEA) were tested by enzyme linked immunosorbent assay, Significant higher serum Cu (120.9 +/- 43.4 vs 99.2 +/- 19.4 mu g/100ml) and lower Zn (68.7 +/- 18.9 vs 80.5 +/- 15.0 mu g/100ml) were observed in recurrent group (P>0.05) and serum copper/zinc (Cu/Zn) ratio was very significantly higher in recurrent group as compared to recurrent- free group (1.85 +/- 0.76 vs 1.26 +/- 0.28 P<0.001), In clinic diagnosis for breast cancer recurrence, at a cutoff value of 1.54, serum copper/zinc(Cu/Zn) ratio had a sensitivity of 69%, specificity of 85%, and diagnostic index of 0.54. When serum copper/zinc( Cu/Zn) ratio combined with the level of serum (CEA) at the same time, the aforementioned value were raised to 91%, 75%, and 0.66, respectively. Ie was suggested that serum copper/zinc(Cu/Zn) ratio, especially when it combined with CEA, may be helpful for the clinic diagnosis of breast cancer recurrence.