Serum calcium levels are elevated among women with untreated postmenopausal breast ca
 

Cancer Causes Control. 2009 Oct 24. [Epub ahead of print]
Serum calcium levels are elevated among women with untreated postmenopausal breast cancer.

Martin E, Miller M, Krebsbach L, Beal JR, Schwartz GG, Sahmoun AE.
University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, USA.
OBJECTIVE: Reports of an association between primary hyperparathyroidism in women and risk of breast cancer suggest an etiologic role for high serum calcium. However, data on the association between serum calcium levels and breast cancer in women without clinical hyperparathyroidism are limited. METHODS: We conducted a hospital-based case-control study among postmenopausal women in Fargo, ND. Cases were women aged 65 and older with newly diagnosed, histologically confirmed breast cancer. Controls were aged 65 and older without clinical cancer who were seen at the same hospital. RESULTS: We obtained data on 190 white cases and 172 white controls. Primary hyperparathyroidism (an abnormally high calcium level confirmed by an abnormally high serum PTH) was found in 3/190 cases and in 0/172 controls (p = 0.25). After excluding the women with primary hyperparathyroidism, the mean calcium levels among cases was 9.6 mg/dL (range, 7.5-11.0, SD = 0.47) vs. 9.4 mg/dL (7.7-10.5, 0.43) among the controls (p < 0.0001). Comparing women in the top with women in the bottom tertile of serum calcium, the multivariable-adjusted odds ratio (OR) for breast cancer was 5.21 (95% CI: 2.59-10.48). There was no relationship between serum calcium and tumor size or stage. CONCLUSION: The distribution of serum calcium levels among postmenopausal women with incident breast cancer was shifted significantly toward the right. These findings are consistent with an effect of early breast tumors on calcium homeostasis. However, the lack of association between serum calcium levels and tumor size or stage supports the hypothesis that subclinical hyperparathyroidism may increase the risk for breast cancer.

PMID: 19856117 [PubMed - as supplied by publisher]

Re: Serum calcium levels are elevated among women with untreated postmenopausal breas
 

Rich, do you think this has any correlation to the theory that bones provide a promotive environment for bc cells?

Hopeful

Re: Serum calcium levels are elevated among women with untreated postmenopausal breas
 

I Don't know. But there does seem to be an ongoing relationship between tumors, bones and endocrine issues. This one really resonated with me since mom had parathyroid surgery a year before her recurrence was discovered. I remember at the time having a weird feeling that she should be scanned. Figured I was being paranoid....

Re: Serum calcium levels are elevated among women with untreated postmenopausal breas
 

Rich,

I agree with you about the endocrine connection. In mid-2004, I was treated (briefly) for subclinical hypothyroidism, which ended when I developed horrible, unrelenting itching pretty much all over, that lasted about 6 months before I got it under control. (I have since read that the itching is a not uncommon symptom of bc, as it reflects an immune system gone bonkers. )My 2005 mammo was clear, but the bc was picked up on the 2006 scan, right around the time it hit 1 cm, the threshold for finding bc on mammos. (I have dense breasts which makes it more difficult to see, also). I remain convinced that the sythroid I took, at very low dose, is responsbile for either initiating or accelerating the bc. All I need to do to satisfy myself is prove it . . .

I also had a lot of bone density loss between 2004 and 2006, more than after I started the AI's. My blood calcium remains in the upper end of normal.

Hopeful