유방암 조직과 정상유선 조직에서 면역조직화학 염색을 이용한 에스트로겐 수용체 베타 발현의 비교 및 임상병리학적 인자들과의 상관관계 분석

Abstract

Purpose: To verify the difference of estrogen receptor (ER) expression between breast cancer and normal mammary tissue and the roles of ER in prognosis of breast cancer, its expression was investigated in normal mammary and breast cancer tissues

Methods: The ER expression of 89 normal mammary and 100 breast cancer tissues was examined using immunohistochemistry. The staining signal was scored by estimating the proportion (range, 0-5) and intensity scores (range, 0-3) of positive cells. The ER expression was considered as positive if the total score (IHC score; range, 0-8) was 3 or more. The ER expressions were compared between normal mammary and breast cancer tissues. The association of ER expression with other clinicopathological factors was also investigated. The distant relapse free survival (DRFS) and overall survival (OS) rates were compared according to the ER expression.

Results: Eighty-eight of the 89 (98.9%) cases of normal mammary tissues and 74 of the 89 (83.1%) counterpart breast cancer tissues showed positive staining with decreased ER expression in the breast cancer compared to the normal mammary tissue with statistical significance (p=0.026). In breast cancer, the ER expression was found to have a positive correlation with the ER expression but with only marginal significance (p=0.063). There was no correlation between the ER expression and other clinicopathological factors (age, tumor size, nodal status, histological grade, progesterone receptor status, and HER-2 expression). The 5 year DRFS and OS rates were found to be independent of ER expression.

Conclusion: The ER expression was significantly decreased in cancer tissues. Further study with a sufficient number of patients is needed to verify the roles of ER during breast cancer carcinogenesis and clinical value.