Trastuzumab + FOLFOX6/FLOT as perioperative therapy for HER2-positive resectable gastric cancer and cardioesophageal transition: RussTrastPraсtik study (interim analysis)

Abstract

Objective. The aim of this study was to evaluate the efficacy and safety of trastuzumab in combination with the FLOT/FOLFOX regimen in the perioperative treatment of resectable HER2-positive locally advanced gastric cancer. Methods. 15 patients were included in two groups; 4 patients were treated with trastuzumab (Herticad®, BIOCAD) + FLOT and 11 patients were treated with trastuzumab (Herticad®, BIOCAD) in combination with FOLFOX. The primary endpoint was incidence of disease stage reduction, tumor regression rate (TRG), change in HER2 tumor status, disease-free and overall survival. Results. Тrastuzumab in combination with FLOT/FOLFOX has a good therapeutic effect and a safety profile in the perioperative treatment of patients with resectable HER2-positive advanced gastric cancer (complete tumor regression [TRG1] was morphologically confirmed in 20% of patients, no pathomorphosis or minimal manifestations [TRG3/TRG4] in 40% of patients, in 40% of patients it was possible to achieve significant pathomorphological tumor regression [TRG2]). In addition, trastuzumab + FLOT gives better results in terms of tumor regression rate than FOLFOX + trastuzumab (cN+/ypN0 disease stage reduction in the T + FLOT group was 100%, whereas in the T + FOLFOX group it was only 30.0%). The HER2 status of the tumor changes against the background of preoperative PCT with the inclusion of trastuzumab (a loss of HER2/ neu protein overexpression was detected in 60% of patients).