title: Diagnostic value of the copper/zinc ratio in digestive cancer: a case control study.
abstract: The aim of this study was to assess the accuracy of the copper/zinc ratio (Cu/Zn ratio) in the evaluation of a large group of patients with digestive cancer compared to gender and age-matched control subjects. A total of 282 patients was studied and separated into three groups: group I (n = 75), patients with digestive cancer, group II (n = 112), patients with benign digestive disease, and group III (n = 95), healthy subjects. Serum levels of copper and zinc were measured by atomic absorption spectrophotometry. The results showed that the serum levels of copper (mg/dL) in patients with digestive cancer (91.6 +/- 27.3, p < 0.05) were significantly higher than in patients with benign digestive disease (75.8 +/- 19.8) or healthy subjects (54.4 +/- 8.9) and the serum levels of zinc (mg/dl) were significantly lower (68.7 +/- 21.9, p < 0.05) compared to benign digestive disease patients (80.1 +/- 18.7) or healthy subjects (100 +/- 11.4 mg/dl). The Cu/Zn ratio was also significantly higher in patients with digestive cancer (1.45 +/- .58, p < 0.05) than those with benign digestive disease (0.95 +/- 0.28) or healthy subjects (0.55 +/- 0.13). Considering a cutoff value of 0.87, the sensitivity of the copper/zinc ratio was 82.2%, with a specificity of 65.7%, a positive predictive value of 45.8% and a negative predictive value of 91.3%. In conclusion, Cu/Zn ratio was found to be considerably higher in patients with digestive cancer compared to age- and gender-matched controls, with a sensitivity of 82.2% that might be useful in the evaluation of suspected malignancy.
authors.affiliation: Gastroenterology Department, Instituto Nacional de la Nutrición Salvador Zubirán, México, D.F., México.
authors.forename: J L
authors.initials: JL
authors.lastname: Poo
authors.forename: R R
authors.initials: RR
authors.lastname: Romero
authors.forename: J A
authors.initials: JA
authors.lastname: Robles
authors.forename: A C
authors.initials: AC
authors.lastname: Montemayor
authors.forename: F
authors.initials: F
authors.lastname: Isoard
authors.forename: A
authors.initials: A
authors.lastname: Estanes
authors.forename: M
authors.initials: M
authors.lastname: Uribe
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D015992:Body Mass Index; D003300:Copper / Q000097:blood*; D003937:Diagnosis, Differential; D004066:Digestive System Diseases / Q000097:blood / Q000175:diagnosis; D004067:Digestive System Neoplasms / Q000097:blood / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D015032:Zinc / Q000097:blood*
chemical_list: D014408:Biomarkers, Tumor; D003300:Copper; D015032:Zinc