Zinc status in benign prostatic hyperplasia and prostate carcinoma.

Sir,

A recent publication on zinc status in benign prostatic hyperplasia and prostate carcinoma is very interesting. Christudoss et al. concluded that “BPH or prostate carcinoma may be associated with a reduction in the levels of tissue zinc, plasma zinc, and an increase in urine zinc/creatinine.”[1] There are some facts to be concerned. First, it is still doubtful whether there is any confounding factor affecting the zinc status in the cases and controls. At least, the food source can be the important confounding factor.[2] Also, some underlying diseases, especially for diabetes mellitus, can result in lowering the blood zinc level.[3] In addition, some mutations that can be seen in the cancerous patients might affect the zinc status. Good examples are some recent reports that quoted “patients with TP53 mutant tumor had lower zinc levels than those with no mutation.”[45] Second, the technique for zinc determination should be clarified as there is no clear information on the technique. Different techniques such as colimetric methods and atomic spectrometry are available for zinc determination with differences in the details of analytical properties.