ESMO 2020: BRCA Mutations and Treatment Outcomes in Metastatic Breast Cancer
Posted: Friday, October 2, 2020
According to findings from the phase III PADA-1 trial, presented at the European Society for Medical Oncology (ESMO) Virtual Congress 2020 (Abstract 304P), first-line combination treatment with an aromatase inhibitor plus palbociclib may result in a greater benefit for patients with hormone receptor–positive/HER2-negative metastatic breast cancer who have BRCA1/2 or PALB2 mutations than for patients without those mutations. Jean-Sebastien Frenel, MD, of the Institut de Cancerologie de l'Ouest in France, and colleagues noted that the development of an ESR1 mutation is a common occurrence among patients with BRCA1/2 or PALB2 mutations.
The trial included 1,017 patients with metastatic breast cancer who were enrolled between March 2017 and January 2019. Patients were stratified according to mutation status: BRCA1, BRCA2, and/or PALB2 mutations (group A; n = 20), wild-type mutations or variants of uncertain significance (group B; n = 125), and nontested (group C; n = 872). Among patients in group A, the majority had BRCA2 mutation (n = 16). A total of 65% of patients with BRCA1/2 mutations and 55% of patients with PALB2 mutations underwent adjuvant palbociclib plus aromatase inhibitor therapy.
At a median follow-up of 21.2 months, the median progression-free survival for patients who underwent aromatase inhibitor plus palbociclib therapy was 14.3 months in group A versus 26.7 months in groups B and C (P = .056). During first-line treatment, the emergence of an ESR1 mutation occurred significantly more often in patients in group A (P = .03).
Disclosure: For full disclosures of the study authors, visit oncologypro.esmo.org.
