Effect of Additional Trastuzumab in Neoadjuvant and Adjuvant Treatment for Patients with Resectable HER2-Positive Gastric Cancer.

Given the improvement in tumor regression and downstaging among NAT patients, and the OS benefit in AT patients, trastuzumab could be considered a promising treatment for locally advanced HER2 + GC patients. In particular, re-evaluation of HER2 status should be considered following NAT combined with trastuzumab.