Ion-exchange chromatography in simultaneous determination of serum copper and zinc levels in patients with cancer of digestive tract.

Serum copper and zinc were simultaneously determined by ion-exchange chromatography (IC) in 35 normal volunteers and 45 patients with benign diseases or different stage cancers of digestive tract. No significant differences of serum Cu, Zn (both expressed in mumol/L) and Cu/Zn ratio were found among normal volunteers, patients with benign diseases and those with stage I or II cancer. While in the group of stage III and IV cancer patients, the mean of serum Cu (26.5 +/- 1.4 mumol/L) and Cu/Zn ratio (2.25 +/- 0.16) increased significantly (P < 0.01) and that of serum Zn (11.8 +/- 0.5 mumol/L) decreased markedly (P < 0.05). Our results showed that serum Cu, Zn and Cu/Zn ratio was of no help in detecting early stage cancers and in differentiating them from benign diseases but was useful in predicting stages of cancers before operation for a better choice of therapy.