title: Pathology parameters and adjuvant tamoxifen response in a randomised premenopausal breast cancer trial.
abstract: BACKGROUND
  Subgroups of breast cancer that have an impaired response to endocrine treatment, despite hormone receptor positivity, are still poorly defined. Breast cancer can be subdivided according to standard pathological parameters including histological type, grade, and assessment of proliferation. These parameters are the net result of combinations of genetic alterations effecting tumour behaviour and could potentially reflect subtypes that respond differently to endocrine treatment.
  
  
  OBJECTIVE
  To investigate the usefulness of these parameters as predictors of the response to tamoxifen in premenopausal women with breast cancer.
  
  
  METHODS
  Clinically established pathological parameters were assessed and related to the tamoxifen response in 500 available tumour specimens from 564 premenopausal patients with breast cancer randomised to either two years of tamoxifen or no treatment with 14 years of follow up. Proliferation was further evaluated by immunohistochemical Ki-67 expression.
  
  
  RESULTS
  Oestrogen receptor positive ductal carcinomas responded as expected to tamoxifen, whereas the difference in recurrence free survival between control and tamoxifen treated patients was less apparent in the relatively few lobular carcinomas. For histological grade, there was no obvious difference in treatment response between the groups. The relation between proliferation and tamoxifen response seemed to be more complex, with a clear response in tumours with high and low proliferation, whereas tumours with intermediate proliferation defined by Ki-67 responded more poorly.
  
  
  CONCLUSIONS
  Clinically established pathology parameters seem to mirror the endocrine treatment response and could potentially be valuable in future treatment decisions for patients with breast cancer.
authors.affiliation: Division of Pathology Department of Laboratory Medicine, Lund University, Malmö University Hospital, SE-205 02, Malmö, Sweden. karin.jirstrom@pat.mas.lu.se
authors.forename: K
authors.initials: K
authors.lastname: Jirström
authors.forename: L
authors.initials: L
authors.lastname: Rydén
authors.forename: L
authors.initials: L
authors.lastname: Anagnostaki
authors.forename: B
authors.initials: B
authors.lastname: Nordenskjöld
authors.forename: O
authors.initials: O
authors.lastname: Stål
authors.forename: S
authors.initials: S
authors.lastname: Thorstenson
authors.forename: G
authors.initials: G
authors.lastname: Chebil
authors.forename: P-E
authors.initials: PE
authors.lastname: Jönsson
authors.forename: M
authors.initials: M
authors.lastname: Fernö
authors.forename: G
authors.initials: G
authors.lastname: Landberg
mesh_terms: D000328:Adult; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000032:analysis; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000737:chemistry / Q000188:drug therapy / Q000473:pathology; D018275:Carcinoma, Lobular / Q000737:chemistry / Q000188:drug therapy / Q000473:pathology; D049109:Cell Proliferation; D017024:Chemotherapy, Adjuvant; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis; D008207:Lymphatic Metastasis; D008875:Middle Aged; D008940:Mitotic Index; D009367:Neoplasm Staging; D017697:Premenopause; D011960:Receptors, Estrogen / Q000032:analysis; D016019:Survival Analysis; D013629:Tamoxifen / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D018931:Antineoplastic Agents, Hormonal; D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D011960:Receptors, Estrogen; D013629:Tamoxifen