Personalizing the treatment of women with early breast cancer: highlights of the St Gallen International Expert Consensus on the Primary Therapy of Early Breast Cancer 2013

Abstract

The 13th St Gallen International Breast Cancer Conference (2013) Expert Panel reviewed and endorsed substantial new evidence on aspects of the local and regional therapies for early breast cancer, supporting less extensive surgery to the axilla and shorter durations of radiation therapy. It refined its earlier approach to the classification and management of luminal disease in the absence of amplification or overexpression of the Human Epidermal growth factor Receptor 2 (HER2) oncogene, while retaining essentially unchanged recommendations for the systemic adjuvant therapy of HER2-positive and ‘triple-negative’ disease. The Panel again accepted that conventional clinico-pathological factors provided a surrogate subtype classification, while noting that in those areas of the world where multi-gene molecular assays are readily available many clinicians prefer to base chemotherapy decisions for patients with luminal disease on these genomic results rather than the surrogate subtype definitions. Several multi-gene molecular assays were recognized as providing accurate and reproducible prognostic information, and in some cases prediction of response to chemotherapy. Cost and availability preclude their application in many environments at the present time. Broad treatment recommendations are presented. Such recommendations do not imply that each Panel member agrees: indeed, among more than 100 questions, only one (trastuzumab duration) commanded 100% agreement. The various recommendations in fact carried differing degrees of support, as reflected in the nuanced wording of the text below and in the votes recorded in supplementary Appendix S1, available at Annals of Oncology online. Detailed decisions on treatment will as always involve clinical consideration of disease extent, host factors, patient preferences and social and economic constraints.

St Gallen molecular subtypes in screening-detected and symptomatic breast cancer in a prospective cohort with long-term follow-up

“…Classification of molecular subtypes was based on St Gallen recommendations14 with IHC analysis of ER, PR and Ki‐67, and silver ISH analysis of HER2. The molecular subtypes were defined as follows: luminal A‐like (ER‐positive and PR more than 20 per cent, low Ki‐67 and HER2‐negative), luminal B‐like HER2‐negative (ER‐positive, PR 20 per cent or less and/or high Ki‐67 and HER2‐negative), luminal B‐like HER2‐positive (ER‐positive and/or PR‐positive, any Ki‐67 and HER2‐positive), HER2‐positive (non‐luminal) (ER‐negative, PR‐negative, any Ki‐67 and HER2‐positive) and triple‐negative (ER‐negative, PR‐negative, HER2‐negative, any Ki‐67).…”

“…High expression levels of the proliferation marker Ki‐67 are related to poor prognosis12. According to the St Gallen 2011 and 2013 guidelines13, 14, a proxy for the molecular subtype classification based on immunohistochemical analysis and in situ hybridization (ISH) of ER, PR, Ki‐67 and HER2 can be used to divide tumours into four to five main subtypes: luminal A‐like, luminal B‐like (HER2‐positive or HER2‐negative), HER2‐positive (non‐luminal) and triple‐negative breast cancer. This classification is important as it provides prognostic information that guides systemic therapy.…”

Prognostic value of the ubiquitin ligase carboxyl terminus of the Hsc70‐interacting protein in postmenopausal breast cancer

“…Moreover, a larger cohort of breast cancer patients revealed that the luminal subgroup may be divided into luminal A and B 29. Luminal B was previously shown to have a more aggressive phenotype, higher HG, and more proliferative index such as Ki67 than luminal A 30, 31, 32. The prognosis of patients with luminal B tumors was also found to be worse than those with luminal A tumors despite treatments with hormonal therapy 33.…”

TGFβ1 regulates HGF‐induced cell migration and hepatocyte growth factor receptor MET expression via C‐ets‐1 and miR‐128‐3p in basal‐like breast cancer

“…Breast cancer subtypes were defined to histopathological characteristics such as receptor status and grading according to the St. Gallen classification and by von Minckwitz and colleagues (Goldhirsch et al ., 2013; von Minckwitz et al ., 2012). …”