Martine Piccart

Sacituzumab govitecan is a standard second-line or later treatment for metastatic triple-negative breast cancer, roughly doubling survival compared with the chemotherapies it was tested against. Patients should expect neutropenia and diarrhoea, which are manageable with growth factor support and loperamide. Trials are now testing it earlier, in first-line combinations with pembrolizumab and after surgery for residual disease.

Everyone with HER2-negative early breast cancer that meets high-risk criteria should be offered germline BRCA testing, because a positive result now changes treatment: a year of olaparib after chemotherapy reduces relapse and death. It does not apply to low-risk tumours, HER2-positive disease, or somatic-only BRCA mutations.

TILs are the strongest cheap prognostic biomarker in early TNBC, scored on a standard slide, and the basis of the de-escalation trials that omit chemotherapy in small, lymphocyte-rich tumours.

This is the sourced bridge between expression subtype and mutation: it tells a clinician that a LAR tumour is the one to sequence for PIK3CA and AKT1, and that immunomodulatory biology is a favourable prognostic group before any immunotherapy.