Successful treatment of primary advanced gastric plasmacytoma using a combination of surgical resection and chemotherapy with bortezomib: A case report

INTRODUCTION: Extramedullary plasmacytoma (EMP) is a plasma cell neoplasm that presents as a solitary tumor. EMP in the gastrointestinal organs are extremely uncommon. PRESENTATION OF CASE: A 36-year-old man was admitted to our hospital with advanced anemia. He had no specific medical history. Gastroendoscopic findings showed an 8.0-cm submucosal tumor with ulcer on the greater curvature of the gastric body. Fine-needle aspiration was performed, and the pathologic diagnosis of the submucosal tumor was a plasmacytoma. Therefore, the patient was diagnosed with gastric plasmacytoma. A total gastrectomy was performed with lymphadenectomy. The result of intraoperative peritoneal lavage cytology was positive. Histological examination revealed serosa-exposed plasmacytoma of the stomach with lymph nodes metastasis. Additionaly the patient received a three-drug chemotherapy regimen (bortezomib, cyclophosphamide, and dexamethasone [VCD]) from 3 weeks after the operation. After 4 cycles of chemotherapy, the patient received autologous peripheral blood stem-cell transplantation (auto-PBSCT). Eighteen months after diagnosis, the patient is in complete remission with no evidence of local relapse or evolution to multiple myeloma. CONCLUSIONS: This is the first reported case of advanced gastric plasmacytoma using adjuvant chemotherapy involving bortezomib and auto-PBSCT after the resection, and the patient has maintained a good course over a year. This protocol could be a new way to treat these tumors.