Summary

In this study, we analyzed vitamin D receptor (VDR) expression and survival in a breast cancer patient cohort of 82 breast

cancer patients. Immunohistochemical analysis was possible in 91.5% of the patients (75/82). Staining was evaluated using the

semi-quantitative assay according to Remmele and Stegner (immunoreactivity score [IRS]). IRS 0–1 was negative/very low, IRS

2–4 was moderate to high, and IRS 6–12 was high. Statistical analysis was performed by Spearman’s correlation test (p<0.05

significant). Overall survival was analyzed using Kaplan-Meier estimations. Only 6 patients had a negative IRS. Moderate IRS

values were present in 20 patients. Most of the patients had a high IRS (49). For survival analysis, data were dichotomized

(IRS 0–4: negative to moderate and IRS 6–12: high VDR expression). In univariate analysis, VDR expression showed significant

differences in progression-free survival (PFS) and overall survival (OS). Patients with high IRS scores showed significantly better

PFS and OS than patients with moderate/negative IRS scores for VDR expression. Tumor size was significantly correlated to

PFS. When analyzed separately, the three different IRS groups showed significant differences in VDR expression. The present

data suggest that VDR expression in breast cancer tissue may be of clinical significance, and the results provide evidence that

VDR may be a factor with prognostic relevance. (J Histochem Cytochem 60:121–129, 2012).

Keywords: breast cancer, vitamin D receptor, immunohistochemistry, prognosis