Bevacizumab combined with low-dose S-1 as maintenance therapy with a long progression-free survival in an elderly patient with heavily pre-treated advanced gastric cancer: A case report

Gastric cancer is known to have a high incidence in several countries around the world, while the treatment of advanced gastric cancer remains a challenge. Recent studies have shown that the antibody bevacizumab, a monoclonal vascular endothelial growth factor antibody, is effective in several solid tumors, while experience regarding its effect on gastric cancer remains limited. An 84-year-old patient with advanced gastric remnant cancer with liver and retroperitoneal lymph node metastasis treated in our hospital benefitted from the use of bevacizumab. Since previous treatment with multiple chemotherapeutic agents resulted in progressive disease (PD), a combined treatment with bevacizumab (intravenously) and low-dose S-1 (orally) was administered. With this individualized treatment, the patient exhibited stable disease (SD) and therapy was maintained for a long period of time as maintenance therapy, with a progression-free survival of similar to 25 months prior to PD. The serum tumor marker cancer antigen (CA) 199 decreased from 508.7 to 188.1 ng/ml. No severe side-effects of bevacizumab were observed, with the exception of controlled grade I bleeding gums due to the long-term use of bevacizumab. Although no large-scale clinical trials have been conducted to evaluate the role of bevacizumab in maintenance therapy and second-or even third-line treatment of advanced gastric cancer, we showed that bevacizumab combined with S-1 was effective and well-tolerated by this patient, suggesting that it be considered a viable option for elderly patients with advanced gastric cancer as maintenance therapy and that it provide a novel treatment for advanced gastric cancer. However, additional clinical trials are required to evaluate the exact effects of long-term bevacizumab treatment on patients with advanced gastric cancer.