Herein, we present the case of a patient with advanced gastric cancer harboring the ERBB3 V104L mutation, who received pyrotinib plus irinotecan as a third-line therapy and achieved a progression-free survival (PFS) of 7.6 months with a high quality of life (QOL).

In this report, we present the case of a 69-year-old man with advanced gastric cancer...Next-generation sequencing performed on paraffin sections of the postoperative tumor samples indicated the presence of the ERBB3 V104L mutation. The patient received irinotecan plus pyrotinib as a third-line therapy and achieved a progression-free survival of 7.6 months with a high quality of life. Therefore, the combined administration of irinotecan and pyrotinib may improve the clinical condition of patients with gastric cancer harboring an ERBB3 mutation.