Copper, zinc, and Cu/Zn ratio in carcinoma of the gallbladder

The exact role of copper and zinc in the etiology of carcinoma of the gallbladder is unclear. Some studies suggest the Cu/Zn ratio is a good indicator of the extent and prognosis in carcinoma of the gastrointestinal tract. The aim of the present study is to estimate the micronutrient profile and Cu/Zn ratio in the serum, tissues, and bile of patients with benign and malignant gallbladder diseases.

The present study was carried out in 60 patients comprising 30 each of carcinoma of the gallbladder and cholelithiasis, and 30 age and sex matched controls. Copper and zinc levels were estimated in blood, bile, and tissue using a Perkin Elmer Model 2380 Atomic absorption Spectrophotometer.

The mean serum zinc levels were significantly lower in patients with carcinoma of the gallbladder than in patients with cholelithiasis and in healthy controls (P < 0.001). The mean serum copper levels were significantly higher in patients with carcinoma of the gallbladder as compared to patients with cholelithiasis and healthy controls (P < 0.001). Biliary and tissue zinc levels were significantly lower in patients with carcinoma of the gallbladder than in patients with cholelithiasis. Biliary and tissue copper levels were higher in patients with carcinoma of the gallbladder than in patients with cholelithiasis. The serum Cu/Zn ratio showed a gradual and significant increase from 1.11 in healthy controls to 1.35 in patients with cholelithiasis and 2.12 in patients with carcinoma of the gallbladder. The biliary and tissue Cu/Zn ratios were also significantly increased in patients with carcinoma of the gallbladder than in patients with cholelithiasis (P < 0.001).

Our data support an association between lower zinc levels and consequently an increased Cu/Zn ratio and carcinoma of the gallbladder. Whether zinc supplementation has a protective effect in preventing carcinoma of the gallbladder needs to be studied further.