title: Characteristics of HER2-positive breast cancer diagnosed following the introduction of universal HER2 testing.
abstract: The aim of this study was to determine the impact of universal HER2 testing on the clinico-pathologic profile of HER2+ breast cancer. Data were extracted from breast cancer pathology reports spanning two periods: before (2003/4, n = 379), and after (2008/9, n = 560) the introduction of universal testing. In 2003/4, 43.3% of breast cancers were tested for HER2 with 16% of tested cases HER2+. In 2008/9, 98.4% of cases were tested with 14.7% HER2+. In 2008/9, HER2+ status was associated with younger age, higher grade, increased tumour size, lymph node involvement, negative oestrogen and/or progesterone receptor status. HER2+ cases diagnosed in 2003/4 were not significantly different in respect of these features. The rate of HER2+ breast cancer amongst screen detected cases in 2008/9 was 8.3%. The phenotype of HER2+ breast cancer was stable following the introduction of universal testing. The overall rate of HER2+ breast cancer was influenced by screen detection.
authors.affiliation: Department of Tissue Pathology and Diagnostic Oncology, Institute of Clinical Pathology and Medical Research, Westmead Hospital, Westmead, NSW 2145, Australia. nirmala.pathmanathan@bci.org.au
authors.forename: Nirmala
authors.initials: N
authors.lastname: Pathmanathan
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Provan
authors.forename: Hema
authors.initials: H
authors.lastname: Mahajan
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Hall
authors.forename: Karen
authors.initials: K
authors.lastname: Byth
authors.forename: A Michael
authors.initials: AM
authors.lastname: Bilous
authors.forename: Rosemary L
authors.initials: RL
authors.lastname: Balleine
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D055088:Early Detection of Cancer / Q000379:methods* / Q000592:standards; D005260:Female; D006801:Humans; D016015:Logistic Models; D008207:Lymphatic Metastasis; D008327:Mammography; D008875:Middle Aged; D060787:Neoplasm Grading; D009517:New South Wales; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D047368:Tumor Burden
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human