A recent phase I study of 11 human epidermal growth factor receptor 2 (HER2)-positive advanced BTC (n = 9) and pancreatic adenocarcinoma (n = 2) patients treated with HER2-targeted CAR-T therapy demonstrated disease control in 4/9 BTC patients, which included a partial response (PR) that lasted 4.5 months. Here, ERBB2 is linked to pancreatic adenocarcinoma.