Association between preoperative serum vitamin D and high-density lipoprotein-cholesterol levels and effects on breast cancer prognosis

Abstract

I want to congratulate Li and colleagues for their article in which they explored the association between the preoperative plasma lipid profile and the prognosis of breast cancer patients. They found that preoperative lower triglycerides (TG) and high-density lipoprotein-cholesterol (HDL-C) levels were risk factors for breast cancer patients. As authors stated that researches about the effect of lipoproteins in breast cancer were contradictory [ [1] Li X. Tang H. Wang J. Xie X. Liu P. Kong Y. et al. The effect of preoperative serum triglycerides and high-density lipoprotein-cholesterol levels on the prognosis of breast cancer. Breast. 2016 Dec 8; 32 ([Epub ahead of print]): 1-6https://doi.org/10.1016/j.breast.2016.11.024 Abstract Full Text Full Text PDF PubMed Scopus (58) Google Scholar ]. Recent study by Ke et al. [ [2] Ke L. Mason R.S. Mpofu E. Vingren J.L. Li Y. Graubard B.I. et al. Hypertension and other cardiovascular risk factors are associated with vitamin D deficiency in an urban Chinese population; a short report. J Steroid Biochem Mol Biol. 2016 Nov 16; (pii: S0960–0760(16)30325-9. [Epub ahead of print])https://doi.org/10.1016/j.jsbmb.2016.11.011 Crossref Scopus (9) Google Scholar ] evaluated the association of 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) with cardiovascular disease risk factors. They reported that lower 25OHD concentrations were significantly associated with lower HDL-C concentrations. Vitamin D deficiency has been reported in a variety of cancers [ [3] Feldman D. Krishnan A.V. Swami S. Giovannucci E. Feldman B.J. The role of vitamin D in reducing cancer risk and progression. Nat Rev Cancer. 2014; 14: 342-357 Crossref PubMed Scopus (891) Google Scholar ]. Many epidemiological studies and meta-analyses have investigated the association of blood 25OHD levels with breast cancer risk with mixed results [ [4] Kim Y. Je Y. Vitamin D intake, blood 25(OH)D levels, and breast cancer risk or mortality: a meta-analysis. Br J Cancer. 2014; 110: 2772-2784 Crossref PubMed Scopus (146) Google Scholar ]. Compared with studies of breast cancer risk, only a few studies examined the association of vitamin D status with prognosis. One study showed higher risk of distant recurrence and death among patients with vitamin D deficiency than those with normal levels [ [5] Goodwin P.J. Ennis M. Pritchard K.I. Koo J. Hood N. Prognostic effects of 25-hydroxyvitamin D levels in early breast cancer. J Clin Oncol. 2009; 27: 3757-3763 Crossref PubMed Scopus (300) Google Scholar ]. Recently, Yao and their colleagues investigated association of serum level of vitamin D at diagnosis with breast cancer survival [ [6] Yao S. Kwan M.L. Ergas I.J. Roh J.M. Cheng T.D. Hong C.C. et al. Association of serum level of vitamin D at diagnosis with breast cancer survival: a case-cohort analysis in the pathways study. JAMA Oncol. 2016 Nov 10; ([Epub ahead of print])https://doi.org/10.1001/jamaoncol.2016.4188 Crossref PubMed Scopus (88) Google Scholar ]. The authors reported that serum 25-hydroxyvitamin D (25OHD) levels were independently associated with breast cancer prognostic characteristics and patient prognosis, most prominently among premenopausal women. As associated with this, we determined the prevalence and prognostic role of vitamin D deficiency in women at initiation of adjuvant treatment for breast cancer [ [7] Altundag M.K. Icli F. Aksoy S. Oksuzoglu O.B. Ozisik Y. Onur H. et al. Correlation of levels of serum 25-hydroxyvitamin D (25-OHD) and lymph node positivity in operable breast cancer: a Turkish Oncology Group study. Fortytsixth Annual Meeting of American Society of Clinical Oncology, Chicago, USA, June 04-08, 2010. J Clin Oncol. 2010; 28 (suppl; abstr 627): 7s Crossref Scopus (26) Google Scholar ]. 407 women with stages I to III breast cancers were enrolled into the study between December 2008 and December 2009. We found a significant association between serum vitamin D level and lymph node status. Serum vitamin D level was significantly lower in breast cancer patients with positive lymph node (p = 0.004). In conclusion, another explanation for association between lower preoperative plasma HDL-C level and worse prognosis of breast cancer might be related to low serum 25OHD levels in these patients population. In conclusion, hypothesis-generating study exploring association between preoperative serum vitamin D and HDL-C levels and their effects on breast cancer prognosis is needed to validate this proposal.