BACKGROUND: Therapies targeting human epidermal growth factor receptor 2 (HER2) have become a focus for improving treatment outcomes in patients with gastric cancer. This literature review sought to assesses clinical outcomes, including safety, survival, and treatment outcomes, of patients who received trastuzumab for the treatment of HER2+ metastatic gastric cancer.
METHODS: Searches were conducted in PubMed and Embase to identify observational research studies investigating the clinical outcomes of trastuzumab and combination therapies for the treatment of HER2+ metastatic gastric cancer, published January 1, 2014–August 22, 2019. Article screening was a two-phase process, and the results of each screening level were documented in accordance with PRISMA.
RESULTS: Twenty articles met the selection criteria for data extraction. Studies focused on treatment patterns or survival, safety, and clinical outcomes, as well as the natural history of disease. In the combined HER2+ patient populations included in this review, tumors were located in the stomach (33.7%), gastroesophageal junction (GEJ, 14.2%), unspecific GEJ or stomach (50.3%), or esophagus (1.9%). Studies observed increases in both overall survival and progression-free survival with the use of trastuzumab-based chemotherapy compared with chemotherapy treatment alone. Additionally, trastuzumab-based chemotherapy appeared to improve survival and clinical outcomes regardless of the presence of multi-organ metastases or tumor location.
CONCLUSIONS: Trastuzumab-treated patients have longer survival times than those not treated with trastuzumab and tolerate treatment well, with few serious adverse events. New treatments for second- and subsequent-line therapies would increase regimen options.
