The prognostic significance of breast cancer resistance protein (BCRP) expression in primary breast carcinoma

Purpose: The aim of the present study was to investigate the expression of breast cancer resistance protein (BCRP) in primary breast carcinoma and to determine whether such expression can predict survival. Methods: Expression of BCRP in 60 breast cancer patients was determined by immunohistochemistry on formalin-fixed, paraffin-embedded tumor section. The relationship between the expression of BCRP with the clinicphathological characteristics and the prognosis of breast cancer patients were also analyzed. Results: ①BCRP expression was observed in 21 of 60 (35%) cases.② BCRP expression was more frequently observed in patients with lymph node metastasis or hormone receptor (P 0. 05) . No relation can be established between expression of BCRP and other clinicophathological parameters (P0. 05) .③Kaplan-Meier analyses revealed that BCRP expression associated only with disease-free survival (DFS) (P 0. 05) and not with overall survival (OS) (P0. 05) . ④In univariate and multivariate Cox regression analyses, tumor size, lymph node metastasis and estrogen receptor (ER) was associated with DFS and OS (P 0. 05) . In addition, progestin receptor (PR) was also associated with OS (P 0. 05) . Conclusions: The results suggest that BCRP is expressed in primary breast carcinoma and is an independent predictive factor for DFS, but do not for OS.