摘要
BACKGROUND In patients with human epidermal growth factor receptor 2(HER2)-overex-pressing gastric cancer(GC),the combination of HER2 targeting and a standard first-line chemotherapy regimen has been demonstrated to significantly improve their prognosis.However,in a proportion of patients,cancer progresses within a short period of time,and there is currently no standard treatment after disease progression.CASE SUMMARY This study presents a case of a 51-year-old male with advanced GC who un-derwent radical resection(Billroth type II subtotal gastrectomy and gastrojejun-ostomy)and resection of liver metastases.Immunohistochemical staining revealed a HER2 score of 2+,a dMMR status,and a Ki67 proliferation index of 30%to 40%.The gene test results indicated the presence of ERBB2 amplification and a PD-L1 expression level of less than 5%.Since December 2021,the patient has experienced disease progression during both first-line(two cycles of KN026 combined with KN046)and second-line(five cycles of nivolumab combined with trastuzumab and SOX chemotherapy)treatment regimens.The patient's prognosis following the first and second lines of treatment was unfavorable,with pro-gression occurring in a relatively short time.For third-line therapy,disitamab vedotin(RC48)plus apatinib was used.At the time of this report,the patient had achieved a progression-free survival(PFS)of 25.8 months,which exceeded the median survival time for patients with advanced GC.CONCLUSION Despite the unfavorable prognosis associated with advanced GC,the imple-mentation of personalized treatment approaches may still prove beneficial for select patients.In patients with HER2-positive GC with extensive metastatic involvement,the use of the HER2-targeted combination with apatinib has demonstrated the potential to prolong both PFS and overall survival.