Research Article
Naoyuki Okamoto
Abstract
Objective: There are increasing reports that many trace elements are playing important roles for biological forms. We used ICP-MS and developed a novel method for precise measurement of serum trace elements called “Metallo- Balance (MB) test” for the screening of cancer risk. Methods: 463 patients with colorectal cancer (men:278; women 185), 277 patients with prostate cancer (men) and 429 patients with breast cancer (women) were collected in Kanagawa cancer center and Chiba cancer center, Japan, while 850 controls (men: 471; women: 379) w/o cancers were obtained from general population. Under IRB approved protocol serum samples were collected and subjected to ICP-MS analysis to measure 17 trace elements (Na, Mg, P, S, K, Ca, Fe, Zn, Cu, Se, Rb, Sr, As, Mo, Cs, Co, Ag). Cancer cases and controls were statistically measured the sensitivity, specificity and area under ROC curve (AUC). Results: High sensitivity, specificity and AUC were confirmed by binominal logistic regression analysis. AUC for colorectal cancer (men) was 0.943 (95% CI, 0.920- 0.966), 0.842 (0.801-0.882) for prostate cancer, 0.898 (0.861-0.935) for colorectal cancer (women), and 0.824 (0.783-0.865) for breast cancer. In particular, sensitivity of 80% or more in stages I and II can be considered effective as a cancer risk screening. Elements that became significant in connection with cancer were Mg, Co, Cu and Mo. Conversely, S, Zn and Rb were less relevant to cancer. Conclusion: These results are considered to indicate that "the balance of trace elements in the blood is largely disrupted from the early stage and onset of cancer". MB test is a promising method for cancer detection and maybe risk assessment.