[Safety and efficacy of laparoscopic surgery in locally advanced gastric cancer patients with neoadjuvant chemotherapy combined with immunotherapy].

Objective: To investigate the safety and efficacy of laparoscopic surgery in locally advanced gastric cancer patients with neoadjuvant SOX chemotherapy combined with PD-1 inhibitor immunotherapy. Methods: Between November 2020 and April 2021, patients with locally advanced gastric cancer who were admitted to the Union Hospital of Tongji Medical College of Huazhong University of Science and Technology were prospectively enrolled in this study. Inclusion criteria were: (1) patients who signed the informed consent form voluntarily before participating in the study; (2) age ranging from 18 to 75 years; (3) patients staged preoperatively as cT3-4N+M0 by the TNM staging system; (4) Eastern Collaborative Oncology Group score of 0-1; (5) estimated survival of more than 6 months, with the possibility of performing R0 resection for curative purposes; (6) sufficient organ and bone marrow function within 7 days before enrollment; and (7) complete gastric D2 radical surgery. Exclusion criteria were: (1) history of anti-PD-1 or PD-L1 antibody therapy and chemotherapy; (2) treatment with corticosteroids or other immunosuppre- ssants within 14 days before enrollment; (3) active period of autoimmune disease or interstitial pneumonia; (4) history of other malignant tumors; (5) surgery performed within 28 days before enrollment; and (6) allergy to the drug ingredients of the study. Follow-up was conducted by outpatient and telephone methods. During preoperative SOX chemotherapy combined with PD-1 inhibitor immunotherapy, follow-up was conducted every 3 weeks to understand the occurrence of adverse reactions of the patients; follow-up was conducted once after 1 month of surgical treatment to understand the adverse reactions and survival of patients. Observation indicators were: (1) condition of enrolled patients; (2) reassessment after preoperative therapy and operation received (3) postoperative conditions and pathological results. Evaluation criteria were: (1) tumor staged according to the 8th edition of the American Joint Committee on Cancer (AJCC) TNM staging system; (2) tumor regression grading (TRG) of pathological results were evaluated with reference to AJCC standards; (3) treatment-related adverse reactions were evaluated according to version 5.0 of the Common Terminology Criteria for Adverse Events; (4) tumor response was evaluated by CT before and after treatment with RECIST V1.1 criteria; and (5) Clavien-Dindo complication grading system was used for postoperative complications assessment. Results: A total of 30 eligible patients were included. There were 25 males and 5 females with a median age of 60.5 (35-74) years. The primary tumor was located in the gastroesophageal junction in 12 cases, in the upper stomach in 8, in the middle stomach in 7, and in the lower stomach in 3. The preoperative clinical stage of 30 cases was III. Twenty-one patients experienced adverse reactions during neoadjuvant chemotherapy combined with immunotherapy, including four cases of CTCAE grade 3-4 adverse reactions resulting in bone marrow suppression and thoracic aortic thrombosis. All cases of adverse reactions were alleviated or disappeared after active symptomatic treatment. Among the 30 patients who underwent surgery, the time from chemotherapy combined with immunotherapy to surgery was 28 (23-49) days. All 30 patients underwent laparoscopic radical gastrectomy, of which 20 patients underwent laparoscopic-assisted radical gastric cancer resection; 10 patients underwent total gastrectomy for gastric cancer, combined with splenectomy in 1 case and cholecystectomy in 1 case. The surgery time was (239.9±67.0) min, intraoperative blood loss was 84 (10-400) ml, and the length of the incision was 7 (3-12) cm. The degree of adenocarcinoma was poorly differentiated in 18 cases, moderately differentiated in 12 cases, nerve invasion in 11 cases, and vascular invasion in 6 cases. The number lymph nodes that underwent dissection was 30 (17-58). The first of gas passage, the first postoperative defecation time, the postoperative liquid diet time, and the postoperative hospitalization time of 30 patients was 3 (2-6) d, 3 (2-13) d, 5 (3-12) d, and 10 (7-27) d, respectively. Postoperative complications occurred in 23 of 30 patients, including 7 cases of complications of Clavien-Dindo grade IIIa or above. Six patients improved after treatment and were discharged from hospital, while 1 patient died 27 days after surgery due to granulocyte deficiency, anemia, bilateral lung infection, and respiratory distress syndrome. The remaining 29 patients had no surgery-related morbidity or mortality within 30 days of discharge. Postoperative pathological examination showed TRG grades 0, 1, 2, and 3 in 8, 9, 4, and 9 cases, respectively, and the number of postoperative pathological TNM stages 0, I, II, and III was 8, 7, 8, and 7 cases, respectively. The pCR rate was 25.0% (8/32). Conclusion: Laparoscopic surgery after neoadjuvant SOX chemotherapy combined with PD-1 inhibitor immunotherapy for locally advanced gastric cancer is safe and feasible, with satisfactory short-term efficacy. Early detection and timely treatment of related complications are important.