Triple negative breast cancer remains without a target therapy. Interventions that could improve pathological complete response (pCR) rates are required. Metabolits of vitamin D could be involved in chemotherapy response.
A series of 147 patients with early or locally advanced triple negative breast cancers was retrospectively analyzed from 2007 to 2016. Patients from 2015 to 2016 period were supplemented with vitamin D and calcium (880UI/1000mg). Analysis of clinicopathological, immune variables and vitamin D pathway were correlated to pCR.
Median age was 53, median tumor size 30mm, 48% had nodal involvement, and median ki67 expression was of 70%. Androgen receptor was expressed in 28% of tumors analyzed, EGFR in 89%, CK5/6 in 63%. Mean stromal T lymphocytes infiltrates (sTILS) was of 28%, mean PDL1 expression of 128, mean 53BP1 expression of 125, and mean VDRnuc expression of 132. pCR rate was of 40%, and within patients with vitamin D supplementation was 64% (16/25). Only VDRnuc expression was associated with pCR (p = 0.047) in the univariate and multivariate analysis. Patients with high expression of VDRnuc in tumor had no evidence of relapse (p = 0.024), with similar curves than those who achieve pCR (p = 0.000).
VDRnuc expression is a strong predictive (p = 0.047 with pCR) and prognostic (p = 0.024 with relapse) in triple negative breast cancer. Role of supplementation needs to be tested if it could improve VDRnuc levels; whereas in our series patients with supplementation had better pCR rates.
Clinical trial identification
Legal entity responsible for the study
Hospital Universitari Arnau de Vilanova de Lleida Institut de Recerca Biomèdica
All authors have declared no conflicts of interest.