title: A hospital-based case-control study of breast-cancer risk factors by estrogen and progesterone receptor status.
abstract: It has been proposed that breast cancers may differ in their pathogenesis and etiology according to their estrogen receptor (ER) and progesterone receptor (PR) status. This hospital-based case-control study in Japan assessed the relationship between known and suspected breast-cancer risk factors and ER and PR status. Information on risk factors was collected from histologically confirmed breast-cancer cases (n = 519) and from cancer-free controls (n = 9,506). Of 160 cases with known ER status, 58 percent were ER-positive; 38 percent of 157 cases with known PR status were PR-positive. No statistically significant differences were found between ER-positive cf ER-negative cases. However, statistically significant differences between PR-positive cf PR-negative cases were observed for number of full-term pregnancies (P = 0.01), menstrual regularity as a teenager (P = 0.024), and occupation as housewife (P = 0.036). Borderline differences were observed for age at menopause (P = 0.074), and age at menarche (P = 0.083). This study provides some evidence that etiologic distinctions may be greater between PR-positive and PR-negative breast cancers than between ER-positive and ER-negative breast cancers.
authors.affiliation: Seoul National University College of Medicine, Korea.
authors.forename: K Y
authors.initials: KY
authors.lastname: Yoo
authors.forename: K
authors.initials: K
authors.lastname: Tajima
authors.forename: S
authors.initials: S
authors.lastname: Miura
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
authors.forename: H
authors.initials: H
authors.lastname: Murai
authors.forename: T
authors.initials: T
authors.lastname: Kuroishi
authors.forename: Y
authors.initials: Y
authors.lastname: Lee
authors.forename: H
authors.initials: H
authors.lastname: Risch
authors.forename: R
authors.initials: R
authors.lastname: Dubrow
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000737:chemistry* / Q000453:epidemiology / Q000209:etiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008875:Middle Aged; D011960:Receptors, Estrogen / Q000032:analysis*; D011980:Receptors, Progesterone / Q000032:analysis*; D012307:Risk Factors
chemical_list: D011960:Receptors, Estrogen; D011980:Receptors, Progesterone