ERBB2 and gastroesophageal junction adenocarcinoma: Showcasing the continued promise of Enhertu®, in 2021 the ADC was approved in the US for a second oncology indication treatment of adult patients with locally advanced or metastatic HER2+ gastric or gastroesophageal junction adenocarcinoma, who have received a prior trastuzumab-based regimen [85,86].