Oestrogen receptor-beta1 but not oestrogen receptor-betacx is of prognostic value in apocrine carcinoma of the breast.
Apocrine carcinoma of the breast, which frequently expresses oestrogen receptor-beta (ER-beta) in the absence of ER-alpha and only infrequently is treated endocrinologically, gives an opportunity to investigate the clinicopathological role of ER-beta in breast cancer independent of ER-alpha expression or tamoxifen treatment. Several isotypes of ER-beta, ER-beta1-5 etc., have been identified thus far; however, the clinicopathological importance of each ER-beta isotype in breast cancer is still uncertain. Here we aimed to clarify the clinicopathological importance of ER-beta1 and ER-betacx (ER-beta2) in apocrine carcinomas, immunohistochemically examining expressions of ER-beta1 and ER-betacx in 47 apocrine carcinomas. Positivity for ER-beta1 and ER-betacx was observed in 41 (87%) and 18 (38%) of 47 cases, respectively. ER-beta1 positivity was related to smaller tumor size (P=0.0359), lower histological grade (P=0.0322), and higher disease-free survival (P<0.0001), whereas ER-betacx status was related to none of these parameters. ER-beta1 positivity was also associated with favorable clinical outcome in 24 so-called triple-negative (ER-alpha-negative/PR-negative/HER2-negative) apocrine carcinomas. ER-beta1 itself, independent of ER-alpha expression and tamoxifen treatment, seems to have a tumor-suppressive effect, at least in apocrine carcinomas. Further study of ER-beta1 is desired to optimize breast cancer treatment.
Honma
Naoko
N
Research Team for Geriatric Diseases, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan. nhonma@tmig.or.jp
Saji
Shigehira
S
Kurabayashi
Rie
R
Aida
Junko
J
Arai
Tomio
T
Horii
Rie
R
Akiyama
Futoshi
F
Iwase
Takuji
T
Harada
Nobuhiro
N
Younes
Mamoun
M
Toi
Masakazu
M
Takubo
Kaiyo
K
Sakamoto
Goi
G
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000096:biosynthesis*; D001943:Breast Neoplasms / Q000378:metabolism / Q000401:mortality* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000401:mortality* / Q000473:pathology; D018572:Disease-Free Survival; D047629:Estrogen Receptor beta / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D011379:Prognosis; D020033:Protein Isoforms / Q000096:biosynthesis; D055815:Young Adult
D014408:Biomarkers, Tumor; D047629:Estrogen Receptor beta; D020033:Protein Isoforms