In line with those findings there is one case report of second line therapy with the antibodies trastuzumab and pertuzumab, thus inhibiting both HER2 and its dimerization, for HER2 overexpressing metastatic ampullary cancer, describing stable disease, with some shrinkage of metastases, and a longer survival than expected upon standard chemotherapy [54]. Here, ERBB2 is linked to carcinoma of the ampulla of vater.