title: Association between HER-2/neu and the progesterone receptor in oestrogen-dependent breast cancer is age-related.
abstract: In oestrogen receptor-positive (ER+) breast cancer, HER-2/neu and the progesterone receptor (PR) are inversely associated. This explains a lower response to anti-oestrogens if ER+ breast cancers are HER-2/neu positive. One randomized study however, showed that premenopausal women with an ER+ breast cancer respond to anti-oestrogens independent of HER-2/neu. We therefore hypothesized an age-related association between HER-2/neu and PR in ER+ breast cancers. Receptors for ER, PR and HER-2/neu were analysed by immunohistochemistry (IHC). A uni- and multivariate analyses was carried out to assess this relationship in 1104 women with an ER+ breast cancer. We observed an inverse association between HER-2/neu and PR only after age 45. There were 173 women of age<or=45 and 931 of age>45 years. In multivariate analysis, only tumour grade (p=0.005) but not PR status was associated with HER-2/neu in women age<or=45 years. However, in age>45 years group, both PR status (p=0.001) and tumour grade (p=0.001) were independently associated with HER-2/neu. In ER+ breast cancers from women age>45, PR was positive in 76.9% if HER-2/neu negative but in 53.4% if HER-2/neu positive (p<0.001) and the median quantitative PR levels are 150 and 75 respectively in HER-2/neu negative and HER-2/neu positive tumours (p=0.002). This age effect of HER-2/neu on the PR status was not seen in women age<or=45 years and the median quantitative PR levels are 200 and 220 respectively in HER-2/neu negative and HER-2/neu positive tumours (p=0.518). The study confirms an age-related inverse relationship between HER-2/neu and PR only in women age>45 years but not in women age<or=45 years.
authors.affiliation: Division of Gynaecologic Oncology in Department of Obstetrics and Gynaecology, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
authors.forename: Huei-Jean
authors.initials: HJ
authors.lastname: Huang
authors.forename: Patrick
authors.initials: P
authors.lastname: Neven
authors.forename: Maria
authors.initials: M
authors.lastname: Drijkoningen
authors.forename: Robert
authors.initials: R
authors.lastname: Paridaens
authors.forename: Hans
authors.initials: H
authors.lastname: Wildiers
authors.forename: Erik
authors.initials: E
authors.lastname: Van Limbergen
authors.forename: Patrick
authors.initials: P
authors.lastname: Berteloot
authors.forename: Frederic
authors.initials: F
authors.lastname: Amant
authors.forename: Marie Rose
authors.initials: MR
authors.lastname: Christiaens
authors.forename: Ignace
authors.initials: I
authors.lastname: Vergote
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000235:genetics* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D015999:Multivariate Analysis; D017698:Postmenopause; D011237:Predictive Value of Tests; D017697:Premenopause; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis / Q000235:genetics*; D011960:Receptors, Estrogen / Q000032:analysis*; D011980:Receptors, Progesterone / Q000032:analysis*
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone