The Impact of Nerve Involvement on the Prognosis of Gastric Cancer Patients with Curative Gastrectomy: An International Multicenter Analysis.

BACKGROUND: Several studies have been conducted to investigate the association between the presence of perineural invasion (PNI) and overall survival (OS) of gastric cancer (GC) patients who underwent curative resection, but no consensus has been reached. This study is aimed at determining the prognostic significance of PNI in gastric cancer. Study Design. The data of 2969 patients with gastric cancer and who had undergone curative gastrectomy from 2006 to 2010 in two high-volume hospitals of China and Korea were retrospectively analyzed. PNI positivity was identified when carcinoma cells were found to infiltrate into the perineurium or neural fascicles. The relationships between PNI and other clinicopathological factors were evaluated, and survival analyses were performed. RESULTS: The presence of PNI was detected in 1055 of the 2969 patients (35.5%). Nationality, age, tumor location, size of tumor, differentiation of the tumor, pT stage, pN stage, lymphatic invasion, and vascular invasion had been associated with PNI positivity. The mean survival time of patients with and without PNI was 62.5 months and 87.3 months, respectively (P < 0.001). However, the presence of PNI was not an independent prognostic factor for gastric cancer, except for patients in stage III (P = 0.037, hazard ratio: 1.21, 95% confidence interval: 1.01-1.44). CONCLUSION: PNI occurs frequently in patients with gastric cancer, and the incidence of PNI increases with the staging of the tumor. The presence of PNI can provide additional information in predicting the survival outcome for those with stage III tumors.

Application of clockwise modularized laparoscopic lymphadenectomy in the suprapancreatic area, a propensity score matching study and comparison with open gastrectomy.

BACKGROUND: Suprapancreatic lymphadenectomy is the essence of D2 radical gastric cancer surgery. The present study aimed to describe clockwise modularized laparoscopic lymphadenectomy in the suprapancreatic area. METHODS: The data from gastric cancer patients who underwent surgical treatment from September 2016 to December 2018 were collected. Patients were divided into clockwise modularized lymphadenectomy (CML) and traditional open gastrectomy (OG) groups according to the surgical treatment strategy. The propensity score matching method was utilized to balance the baseline characteristics between the two groups. RESULTS: Finally, 551 gastric cancer patients were included in the present study. Following propensity score matching, 106 pairs of patients in the CML group and OG group were included in the final analysis. The CML group had more total examined lymph nodes (36, IQR 28-44.74 vs. 29, IQR 29-39.5, p = 0.002) and no. 9 station nodes (2, IQR 1-5 vs. 2, IQR 1-3, p = 0.007) than the OG group. There was less intraoperative blood loss (30, IQR 20-80 ml vs. 80, IQR 50-80 ml, p < 0.001) and a longer surgical duration (262.5 min, IQR 220-303.25 min vs. 232, IQR 220-255 min, p < 0.001) in the CML group than in the OG group. The incidence of postoperative complications (19.8% vs. 16.0%, p = 0.591) and postoperative hospital stay (8, IQR 7-9 days vs. 8, IQR 7-9 days, p = 0.452) were comparable between the CML and OG groups. CONCLUSION: Laparoscopic lymphadenectomy for gastric cancer surgery is technically demanding. Clockwise modularized laparoscopic lymphadenectomy in the suprapancreatic area can attain similar effects as traditional open surgery and without an increase in postoperative adverse events.