23P Prediction of response to atezolizumab plus nab-paclitaxel in unresectable locally advanced triple-negative breast cancer (TNBC): The clinical usefulness of PD-L1 mRNA expression in plasma-derived exosomes

Atezolizumab plus nanoparticle albumin-bound (nab)-paclitaxel prolonged progression-free survival (PFS) and overall survival (OS) among patients with unresectable locally advanced TNBC but its use is hampered by the lack of reliable predictors of tumor response. The study evaluates whether PD-L1 mRNA copies per ml in plasma-derived exosomes may predict response to anti-PD-L1 antibodies early in the course of therapy. Seventy-seven consecutive...