Evidence for increased non-ceruloplasmin copper in early-stage human breast cancer serum

We measured total serum copper and ceruloplasmin levels in pre- and postmenopausal Stage I and II breast cancer (BC) patients and omnivorous and vegetarian controls. The omnivorous groups included 14 premenopausal women [33 +/- 6 (SD) yrs] and 11 postmenopausal women (57 +/- 5 yrs), and the vegetarian groups were comprised of 12 premenopausal subjects (34 +/- 7 yrs) and 11 postmenopausal subjects (59 +/- 5 yrs). There were 13 premenopausal BC patients (39 +/- 7 yrs) and 10 postmenopausal BC patients (66 +/- 6 yrs). Fasting serum samples were taken on three consecutive days, typically four times in the year. Serum ceruloplasmin levels (g/l) were measured by nephelometry utilizing monoclonal antiserum, and total serum copper levels (mumol/l) were determined by proton-induced X-ray emission analysis. Premenopausal patients had higher serum copper levels than their controls (mean 18.7 vs. 16.6, p less than 0.03). For ceruloplasmin, the postmenopausal BC patients had significantly lower levels than pooled postmenopausal controls (0.309 vs. 0.370, p less than 0.001). The copper-to-ceruloplasmin ratio was significantly higher in the pooled cancer groups than in the pooled control groups (3.69 vs. 3.21, p less than 0.001), with similar patterns in both pre- and postmenopausal classes. This high serum copper-to-ceruloplasmin ratio in BC patients may reflect disordered copper metabolism in this disease, which could also have implications for the origin of, or the response to, the cancer process.