Safety and efficacy of adjuvant chemotherapy with oxaliplatin and S-1 for patients with locally advanced gastric cancer after D2 lymph nodes dissection / 中华胃肠外科杂志

Objective: To investigate the safety and efficacy of oxaliplatin combined with S-1 (SOX) as adjuvant chemotherapy after D2 radical gastrectomy for locally advanced gastric cancer. Methods: A descriptive case series study was applied. Case inclusion criteria: (1) locally advanced gastric cancer confirmed by endoscopic biopsy or surgical specimen pathology as gastric adenocarcinoma; (2) receiving D2 radical gastric resection followed by SOX regimen adjuvant chemotherapy. Case exclusion criteria: (1) postoperative pathological TNM stage I or IV; (2) acute complications and emergency surgeries; (3) receiving neoadjuvant therapy; (4) concurrent malignancies and complications compromising patients' treatment or survival; (5) without receiving adjuvant SOX chemotherapy. A total of 94 patients with stage II-III gastric cancer who underwent D2 radical gastrectomy and postoperative adjuvant SOX chemotherapy at department of Gastrointestinal Surgery, Peking University People's Hospital from January 2014 to December 2019 were retrospectively enrolled. Chemotherapy-related adverse events, overall survival (OS) and progression-free survival (PFS) were analyzed. Kaplan-Meier survival analysis was performed and log rank test was used to analyze the difference between groups. P<0.2 or clinically significant indicators in univariate analysis were included in Cox regression model for multivariate survival analysis. Results: Among these 94 patients, there were 65 males and 29 females with an average age of (58.2±12.1) years; 33 patients with hypertension, diabetes mellitus, or cardiovascular and cerebrovascular diseases, 11 patients with family history of gastrointestinal tumors; 59 patients with tumors locating in the antrum or pylorus, 16 patients in the gastric body, 19 patients in the gastric fundus or cardia; 29 patients underwent total gastrectomy, 5 patients underwent proximal subtotal gastrectomy, and 60 patients underwent distal subtotal gastrectomy. In this study, 73 patients (77.7%) completed at least 5 cycles of adjuvant SOX regimen chemotherapy. Grade 3-4 adverse reactions included thrombocytopenia (23.4%, 22/94), nausea and vomiting (18.1%, 17/94) and peripheral neurotoxicity (6.4%, 6/94). Eighty-nine patients (94.7%) completed follow-up with a median follow-up time of 32 months. The 3-year and 5-year OS rates were 89.8% and 83.7%, respectively, and the 3-year and 5-year PFS rates were 81.4% and 78.1%, respectively. Taking 5 chemotherapy cycles as the cut-off point, the 3-year OS rate and 3-year PFS rate were 72.2% and 53.9% in the adjuvant chemotherapy < 5 cycles group, and 93.7% and 87.1% in the adjuvant chemotherapy ≥5 cycles group, respectively; the differences were statistically significant (P=0.029, P=0.006). Univariate analysis showed that the adjuvant chemotherapy < 5 cycles group was associated with worse 3-year OS (P=0.029). Multivariate analysis showed that insufficient chemotherapy cycle (HR=9.419, 95% CI: 2.330-38.007, P=0.002) was an independent risk factor for 3-year OS. Meanwhile, univariate analysis showed that the adjuvant chemotherapy <5 cycles (P=0.006), preoperative CEA > 4.70 μg/L (P=0.035) and adjacent organ resection (P=0.024) were associated with worse 3-year PFS. Multivariate analysis showed that adjuvant chemotherapy <5 cycles (HR=10.493, 95% CI: 2.466-44.655, P=0.001) and adjacent organ resection (HR=127.518, 95% CI: 8.885-1 830.136, P<0.001) were independent risk factors for 3-year PFS. Conclusions: Oxaliplatin combined with S-1 as an adjuvant chemotherapy regimen for locally advanced gastric cancer has high efficacy and low incidence of adverse reactions. At least 5 cycles of SOX regimen adjuvant chemotherapy can significantly improve prognosis of patients with stage II-III gastric cancer.

Safety and effectiveness of oxaliplatin combined with capecitabine or oxaliplatin combined with S-1 neoadjuvant chemotherapy in the treatment of advanced gastric cancer / 中华胃肠外科杂志

Objective: To explore the safety and efficacy of oxaliplatin plus capecitabine (CapeOX) or oxaliplatin plus S-1 (SOX) regimen neoadjuvant chemotherapy in the treatment of advanced gastric cancer. Methods: A retrospective cohort study was performed. Clinical data of patients diagnosed as advanced gastric cancer undergoing CapeOX/SOX neoadjuvant chemotherapy and standard laparoscopic radical operation for gastric cancer in Ruijin Hospital of Shanghai Jiaotong University School of Medicine from April 2016 to April 2019 were retrospectively collected. Inclusion criteria were as follows: (1) age≥18 years; (2) gastric adenocarcinoma was confirmed by histopathology and the clinical stage was T3-4aN+M0; (3) tumor could be resectable; (4) preoperative neoadjuvant chemotherapy was CapeOX or SOX regimen without radiotherapy or other regimen chemotherapy; (5) no other concurrent malignant tumor; (6) the Eastern Cooperative Oncology Group (ECOG) score ≤ 1; (7) no bone marrow suppression; (8) normal liver and kidney function. Exclusion criteria were as follows: (1) patients with recurrent gastric cancer; (2) patients receiving emergency surgery due to tumor perforation, bleeding, obstruction, etc.; (3) allergy to oxaliplatin, S-1, capecitabine or any drug excipients; (4) diagnosed with coronary heart disease, cardiomyopathy, or the New York Heart Association class III or IV; (5) pregnant or lactating women. A total of 118 patients were enrolled as the neoadjuvant chemotherapy group, and 379 patients with locally advanced gastric cancer who received surgery combined with postoperative adjuvant chemotherapy over the same period simultaneously were included as the adjuvant chemotherapy group. After propensity score matching was performed including gender, age, ECOG score, tumor site, clinical stage, chemotherapy regimen and other factors by 1:1 ratio, there were 40 cases in each group. The differences between the two groups in general conditions, efficacy of neoadjuvant chemotherapy, intraoperative conditions, postoperative conditions, histopathological results, chemotherapy-related adverse events, and survival status were compared and analyzed. Results: Comparison of baseline demographics between the two groups showed no statistically significant difference (all P>0.05). In the neoadjuvant chemotherapy group, 5.0% (2/40) of patients achieved clinical complete response, 57.5% (23/40) achieved partial response, 32.5% (13/40) remained stable disease, and 5.0% (2/40) had disease progression before surgery. Objective response rate was 62.5% (25/40), and disease control rate was 95.0% (38/40). There were no statistically significant differences between neoadjuvant chemotherapy group and adjuvant chemotherapy group in terms of operation time, intraoperative blood loss, number of lymph node harvested, length of postoperative hospital stay, and postoperative mortality and morbidity (all P>0.05). Postoperative complications were well managed with conservative treatment. No Clavien-Dindo IV or V complications were observed in both groups. Pathological results showed that the proportion of patients with pathological stage T1 in the neoadjuvant chemotherapy group was significantly higher than that in the adjuvant chemotherapy group [27.5% (11/40) vs. 5.0% (2/40)], while the proportion of patients with pathological stage T3 was significantly lower than that in the adjuvant chemotherapy group [20.0% (8/40) vs. 45.0% (18/40)], with statistically significant difference (χ(2)=15.432, P=0.001). In the neoadjuvant chemotherapy group, there were 4 cases of tumor regression grade 0, 8 cases of grade 1, 16 cases of grade 2, and 12 cases of grade 3. The pathological complete response rate was 10% (4/40), the overall pathological response rate was 70.0% (28/40). There was no statistically significant difference in the incidence of chemotherapy-related adverse events between neoadjuvant chemotherapy group and adjuvant chemotherapy group [40% (16/40) vs. 37.5% (15/40), P>0.05). There were no statistically significant differences in OS (43 months vs. 40 months) and 3-year OS rate (66.1% vs. 59.8%) between neoadjuvant chemotherapy group and adjuvant chemotherapy group (P=0.428). The disease-free survival (DFS) and 3-year DFS rates of the neoadjuvant chemotherapy group were significantly superior to those of the adjuvant chemotherapy group (36 months vs. 28 months, 51.4% vs. 35.8%, P=0.048). Conclusion: CapeOX or SOX regimen neoadjuvant chemotherapy is a safe, effective and feasible treatment mode for advanced gastric cancer without increasing surgical risk and can improve the DFS of patients.

S-1 Monotherapy as a Neoadjuvant Treatment for Locally Advanced Gastric Cancer

S-1, a novel oral fluoropyrimidine, is an effective therapeutic agent for gastric cancer. Herein, we report a case with locally advanced gastric cancer that achieved a curative resection after S-1 monotherapy as neoadjuvant treatment. A 68-year-old man was diagnosed with gastric cancer and massive lymphadenopathy involving the perigastric, celiac axis and splenic hilum. His clinical stage was cT3N2H0P0M0. Considering his relatively poor performance (ECOG 2, severe weight loss) and advanced age, we started the patient on S-1 monotherapy at a dose of 35 mg/m2 bid for 4 consecutive weeks followed by a 2-week rest. Follow-up study after 4 treatment cycles revealed disappearance of the lymphadenopathy of the perigastric and celiac axis with diminished extension of the stomach mass. The patient had a partial response (PR) with a 72% tumor reduction, according to the Response Evaluation Criteria in Solid Tumors (RECIST). His performance status was improved to an ECOG 1 and he gained 7 kg. A curative (R0) resection was achieved with a radical total gastrectomy and D2 dissection. The pathological stage was pT3N2M0, stage IIIB. In conclusion, S-1 neoadjuvant chemotherapy aided in the treatment of gastric cancer in this patient.