Conversion surgery for stage IV gastric cancer with a complete pathological response to nivolumab: a case report

Abstract

Background Patients with stage IV gastric cancer have a poor prognosis despite the recent development of multidisciplinary treatments that include chemotherapy. However, conversion surgery has emerged as a promising strategy to improve the prognosis in responders with unresectable gastric cancer after chemotherapy. Moreover, nivolumab is currently recommended as a third-line treatment in patients with unresectable advanced gastric cancer. However, there are few reports of conversion surgery after nivolumab in patients with stage IV gastric cancer. Case presentation A 68-year-old woman complaining of nausea was diagnosed with stage I gastric cancer (T2N0M0). Although we planned gastrectomy with lymphadenectomy, multiple liver metastases were detected during the surgery. After staging laparoscopy, we diagnosed this patient as having stage IV unresectable gastric cancer, and we administered chemotherapy and immunotherapy for 39 months (first-line regimen: 6 courses of S-1 plus oxaliplatin; second-line regimen: 6 courses of ramucirumab plus paclitaxel; and third-line regimen: 20 courses of nivolumab). Although the liver metastases completely disappeared after the second-line chemotherapy, lung metastases and a rapid enlargement of the primary tumor were confirmed. Consequently, the patient received nivolumab at a dose of 3 mg/kg intravenously every 2 weeks, then a dose of 240 mg/kg intravenously every 2 weeks from September 2018. After 20 courses of nivolumab, the primary tumor dramatically shrank and the lung metastases disappeared. The patient had a partial primary tumor response to nivolumab. Therefore, the patient underwent laparoscopic distal gastrectomy with D2 lymph node dissection. The macroscopic examination of the resected specimen showed an ulcer scar in the primary tumor site. The pathological examination demonstrated no residual tumors and no lymph node metastases, and the histological response of the primary tumor was categorized as grade 3. The postoperative course was uneventful, and the patient is receiving nivolumab to control potential liver and lung metastases. Conclusions Conversion surgery might help control tumor progression in responders after chemotherapy and immunotherapy.

Pathological Complete Response and Successful Conversion Surgery After Nivolumab Therapy for Stage IV Oesophagogastric Junction Cancer

“…Only three recent cases of conversion gastrectomy in patients with stage IV GC after nivolumab therapy have been reported (7)(8)(9). The authors of a prior case report concluded that extended surgery should be carefully considered because pancreatic fistula and anastomotic leakage occurred in their patient (8).…”

“…Recently, the CheckMate649 phase III trial reported that nivolumab plus chemotherapy was a potential standard first-line treatment for metastatic GC or OGJC that expresses programmed cell death-1-ligand (PD-L1), and it was recently granted FDA approval in the United States (6). Currently, three cases of advanced GC treated with conversion surgery after nivolumab treatment have been reported (7)(8)(9). However, there is limited information regarding the use, safety, and associated oncological outcomes of conversion surgery after nivolumab treatment for advanced GC.…”

Extended total gastrectomy after nivolumab for unresectable multivisceral invasive gastric cancer

“…To our knowledge, this is the third report of conversion surgery for advanced GC after nivolumab as third-line chemotherapy [ 3 , 4 ].…”

“…Yoshida et al [ 2 ] noted that this is because tegafur, gimeracil, and oteracil potassium-based regimens are necessary for a good response. However, a rare case of conversion gastrectomy after third-line chemotherapy with nivolumab (Bristol-Myers Squibb, Princeton, NJ and Ono Pharmaceutical, Trenton, NJ), a human immunoglobulin G4 programmed cell death protein 1-blocking monoclonal antibody, has been reported [ 3 , 4 ].…”

Conversion surgery for metastatic gastric cancer at 2 years after initial diagnosis of cancer of unknown primary with metastasis of cervical lymph nodes and ovary: a case report

“…Although there are a few case reports on conversion surgery for gastric cancer [5][6][7], none describe a case that was initially diagnosed as cancer of unknown primary (CUP). Here we report a case of successful conversion surgery that was performed after a cervical lymphadenectomy and a bilateral oophorectomy, wherein definitive diagnosis of gastric cancer could only be established about 2 years after an initial diagnosis of CUP.…”