The 11th St Gallen (Switzerland) expert consensus meeting on the primary treatment of early breast cancer in March 2009 maintained an emphasis on targeting adjuvant systemic therapies according to subgroups deﬁned by predictive markers. Any positive level of estrogen receptor (ER) expression is considered sufﬁcient to justify the use of endocrine adjuvant therapy in almost all patients. Overexpression or ampliﬁcation of HER2 by standard criteria is an indication for anti-HER2 therapy for all but the very lowest risk invasive tumours. The corollary is that ER and HER2 must be reliably and accurately measured. Indications for cytotoxic adjuvant therapy were reﬁned, acknowledging the role of risk factors with the caveat that risk per se is not a target. Proliferation markers, including those identiﬁed in multigene array analyses, were recognised as important in this regard. The threshold for indication of each systemic treatment modality thus depends on different criteria which have been separately listed to clarify the therapeutic decision-making algorithm.
Publication Name: Annals of Oncology