Truly personalized therapy — an end to the era of one size fits all

In 2018, several trials in breast cancer have shown efficacy of strategies that rely on novel markers, including gene expression assays or pathological complete response. The relevance of targeted strategies in patient subgroups and of immunotherapy efficacy were demonstrated.

Key advances

• Patients with node-negative luminal early stage breast cancer and a low or intermediate Oncotype DX recurrence score do not benefit from the addition of adjuvant chemotherapy to endocrine therapy¹.

• Patients with HER2-positive luminal early stage breast cancer and without a pathological complete response after neoadjuvant chemotherapy would benefit substantially from escalation of adjuvant therapy by switching to T-DM1 (ref.⁴).

• Results on the efficacy of three cyclin-dependent kinase (CDK)4/6 inhibitors in all major phase III trials in patients with metastatic luminal breast cancer have now been presented, including one showing an overall survival (OS) benefit^5,6,7.

• In patients with PIK3CA-mutated metastatic breast cancer, alpelisib substantially improves progression-free survival (PFS) with a manageable toxicity profile⁸.

• In patients with BRCA-mutated metastatic breast cancer, the addition of talazoparib to standard chemotherapy provided a PFS advantage over chemotherapy alone⁹.

• In patients with triple-negative metastatic breast cancer, addition of atezolizumab to chemotherapy improved both PFS and OS; the strongest benefit was associated with expression of programmed cell death 1 ligand 1 (PD-L1)¹¹.