title: Impact of MammaPrint on Clinical Decision-Making in South African Patients with Early-Stage Breast Cancer.
abstract: The aim of the study was to evaluate the impact of MammaPrint on treatment decision-making in patients with breast cancer. Clinicopathologic information of all breast cancer patients referred for MammaPrint testing in South Africa was collected from 2007 until 2014. A total of 107 patients (109 tumors) with estrogen receptor/progesterone receptor positive and human epidermal growth factor receptor-2 negative tumors were selected with tumors ≥10 mm, or when 1-3 nodes were involved without extra-nodal extension. None of the clinical indicators correlated significantly with the MammaPrint risk classification, which changed the decision for adjuvant chemotherapy in 52% of patients. Of 60 patients who were clinically high risk, 62% had a low-risk MammaPrint result and of the 47 clinically low -risk patients 40% had a high-risk MammaPrint result. This study indicates that MammaPrint could reduce the need for adjuvant chemotherapy by 17% using the selection criteria stipulated. The significant impact on treatment decisions confirmed the clinical utility of MammaPrint independent of standard clinicopathologic risk factors as supported by long-term clinical outcome studies.
authors.affiliation: Department of Surgery, University of Stellenbosch, Tygerberg, South Africa.
authors.forename: Heinrich
authors.initials: H
authors.lastname: Pohl
authors.affiliation: Division of Anatomical Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, University of Stellenbosch, Tygerberg, South Africa.
authors.forename: Maritha J
authors.initials: MJ
authors.lastname: Kotze
authors.affiliation: Division of Anatomical Pathology, Department of Pathology, Faculty of Medicine and Health Sciences, University of Stellenbosch, Tygerberg, South Africa.|Department of Biomedical Sciences, Faculty of Health and Wellness, Cape Peninsula University of Technology, Bellville, South Africa.
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Grant
authors.affiliation: Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, University of Stellenbosch, Tygerberg, South Africa.|Department of Statistics, University of the Western Cape, Bellville, South Africa.
authors.forename: Lize
authors.initials: L
authors.lastname: van der Merwe
authors.affiliation: GVI Oncology, Mediclinic Panorama, Cape Town, South Africa.
authors.forename: Fredrieka M
authors.initials: FM
authors.lastname: Pienaar
authors.affiliation: Department of Surgery, University of Stellenbosch, Tygerberg, South Africa.
authors.forename: Justus P
authors.initials: JP
authors.lastname: Apffelstaedt
authors.affiliation: Department of Surgery, University of Stellenbosch, Tygerberg, South Africa.|Private Practice, Mediclinic Panorama, Cape Town, South Africa.
authors.forename: Ettienne J
authors.identifier: http://orcid.org/0000-0001-7511-0114
authors.initials: EJ
authors.lastname: Myburgh
mesh_terms: D000328:Adult; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology*; D017024:Chemotherapy, Adjuvant; D000066491:Clinical Decision-Making; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods*; D006801:Humans; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D012307:Risk Factors; D013019:South Africa
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; C508053:ERBB2 protein, human
keywords: Mammaprint; adjuvant chemotherapy; breast cancer; genomic profiling; impact