[Simultaneous determination of serum copper and zinc levels in patients with cancer of the digestive tract by ion-exchange chromatography].

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 the digestive tract. No significant differences of serum Cu, Zn and Cu/Zn ratio were found among normal volunteers, patients with benign diseases and those with stage I or II cancers, while in the group of stage III and IV cancer patients, serum Cu (26.53 +/- 1.41 mumol/L) and Cu/Zn ratio (2.25 +/- 0.16) were very significantly elevated (P < 0.01) and that of serum Zn (11.78 +/- 0.46 mumol/L) was remarkably decreased (P < 0.05). Our results showed that serum Cu, Zn and Cu/Zn ratio were of no help in detecting early stage cancers and in differentiating them from benign diseases but were useful in predicting stages of cancers before operation for a better choice of therapy.