The minimum number of examined lymph nodes was 24 for optimal survival of pathological T2-4 gastric cancer: a multi-center, hospital-based study covering 20 years of data.

INTRODUCTION: The current National Comprehensive Cancer Network (NCCN) guidelines recommend that at least 16 lymph nodes should be examined for gastric cancer patients to reduce staging migration. However, there is still debate regarding the optimal management of examined lymph nodes (ELNs) for gastric cancer patients. In this study, we aimed to develop and test the minimum number of ELNs that should be retrieved during gastrectomy for optimal survival in patients with gastric cancer. METHODS: We used the restricted cubic spline (RCS) to identify the optimal threshold of ELNs that should be retrieved during gastrectomy based on the China National Cancer Center Gastric Cancer (NCCGC) database. Northwest cohort, which sourced from the highest gastric cancer incidence areas in China, was used to verify the optimal cutoff value. Survival analysis was performed via Kaplan-Meier estimates and Cox proportional hazards models. RESULTS: In this study, 12,670 gastrectomy patients were included in the NCCGC cohort and 4941 patients in the Northwest cohort. During 1999-2019, the average number of ELNs increased from 17.88 to 34.45 nodes in the NCCGC cohort, while the number of positive lymph nodes remained stable (5-6 nodes). The RCS model showed a U-curved association between ELNs and the risk of all-cause mortality, and the optimal threshold of ELNs was 24 [Hazard ratio (HR) = 1.00]. The ELN ≥ 24 group had a better overall survival (OS) than the ELN < 24 group clearly (P = 0.003), however, with respect to the threshold of 16 ELNs, there was no significantly difference between the two groups (P = 0.101). In the multivariate analysis, ELN ≥ 24 group was associated with improved survival outcomes in total gastrectomy patients [HR = 0.787, 95% confidence interval (CI): 0.711-0.870, P < 0.001], as well as the subgroup analysis of T2 patients (HR = 0.621, 95%CI: 0.399-0.966, P = 0.035), T3 patients (HR = 0.787, 95%CI: 0.659-0.940, P = 0.008) and T4 patients (HR = 0.775, 95%CI: 0.675-0.888, P < 0.001). CONCLUSION: In conclusion, the minimum number of ELNs for optimal survival of gastric cancer with pathological T2-4 was 24.

Perioperative Chemotherapy Could Not Improve the Prognosis of Gastric Cancer Patients With Mismatch Repair Deficiency: A Multicenter, Real-World Study.

INTRODUCTION: To date, the role of deficient mismatch repair (dMMR) remains to be proven in gastric cancer, and it is difficult to judge its value in clinical application. Our study aimed to investigate how MMR status affected the prognosis in patients with gastrectomy, as well as the efficacy of neoadjuvant chemotherapy and adjuvant chemotherapy in patients with dMMR with gastric cancer. MATERIALS AND METHODS: Patients with gastric cancer with certain pathologic diagnosis of dMMR or proficient MMR (pMMR) using immunohistochemistry from 4 high-volume hospitals in China were included. Propensity score matching was used to match patients with dMMR or pMMR in 1:2 ratios. Overall survival (OS) and progression-free survival (PFS) curves were plotted using the Kaplan-Meier method and compared statistically using the log-rank test. Univariate and multivariate Cox proportional hazards models based on hazard ratios (HRs) and 95% confidence intervals (CIs) were used to determine the risk factors for survival. RESULTS: In total, data from 6176 patients with gastric cancer were ultimately analyzed, and loss of expression of one or more MMR proteins was observed in 293 patients (293/6176, 4.74%). Compared to patients with pMMR, patients with dMMR are more likely to be older (≥66, 45.70% vs. 27.94%, P < .001), distal location (83.51% vs. 64.19%, P < .001), intestinal type (42.21% vs. 34.46%, P < .001), and in the earlier pTNM stage (pTNM I, 32.79% vs. 29.09%, P = .009). Patients with gastric cancer with dMMR showed better OS than those with pMMR before PSM (P = .002); however, this survival advantage was not observed for patients with dMMR after PSM (P = .467). As for perioperative chemotherapy, results of multivariable Cox regression analysis showed that perioperative chemotherapy was not an independent prognostic factor for PFS and OS in patients with dMMR with gastric cancer (HR = 0.558, 95% CI, 0.270-1.152, P = .186 and HR = 0.912, 95% CI, 0.464-1.793, P = .822, respectively). CONCLUSION: In conclusion, perioperative chemotherapy could not prolong the OS and PFS of patients with dMMR with gastric cancer.

Using nomogram, decision tree, and deep learning models to predict lymph node metastasis in patients with early gastric cancer: a multi-cohort study.

The accurate assessment of lymph node metastasis (LNM) in patients with early gastric cancer is critical to the selection of the most appropriate surgical treatment. This study aims to develop an optimal LNM prediction model using different methods, including nomogram, Decision Tree, Naive Bayes, and deep learning methods. In this study, we included two independent datasets: the gastrectomy set (n=3158) and the endoscopic submucosal dissection (ESD) set (n=323). The nomogram, Decision Tree, Naive Bayes, and fully convolutional neural networks (FCNN) models were established based on logistic regression analysis of the development set. The predictive power of the LNM prediction models was revealed by time-dependent receiver operating characteristic (ROC) curves and calibration plots. We then used the ESD set as an external cohort to evaluate the models' performance. In the gastrectomy set, multivariate analysis showed that gender (P=0.008), year when diagnosed (2006-2010 year, P=0.265; 2011-2015 year, P=0.001; and 2016-2020 year, P<0.001, respectively), tumor size (2-4 cm, P=0.001; and ≥4 cm, P<0.001, respectively), tumor grade (poorly-moderately, P=0.016; moderately, P<0.001; well-moderately, P<0.001; and well, P<0.001, respectively), vascular invasion (P<0.001), and pT stage (P<0.001) were independent risk factors for LNM in early gastric cancer. The area under the curve (AUC) for the validation set using the nomogram, Decision Tree, Naive Bayes, and FCNN models were 0.78, 0.76, 0.77, and 0.79, respectively. In conclusion, our multi-cohort study systematically investigated different LNM prediction methods for patients with early gastric cancer. These models were validated and shown to be reliable with AUC>0.76 for all. Specifically, the FCNN model showed the most accurate prediction of LNM risks in early gastric cancer patients with AUC=0.79. Based on the FCNN model, patients with LNM rates of >4.77% are strong candidates for gastrectomy rather than ESD surgery.

Various approaches of laparoscopic common bile duct exploration plus primary duct closure for choledocholithiasis: A systematic review and meta-analysis.

BACKGROUND: Common bile duct (CBD) stones may occur in up to 3%-14.7% of all patients with cholecystectomy. Various approaches of laparoscopic CBD exploration plus primary duct closure (PDC) are the most commonly used and the best methods to treat CBD stone. This systematic review was to compare the effectiveness and safety of the various approaches of laparoscopic CBD exploration plus PDC for choledocholithiasis. DATA SOURCES: Randomized controlled trials (RCTs) and non-randomized controlled trials (NRCTs) (case-control studies or cohort studies) were searched from Cochrane library (until Issue 2, 2015), Web of Science (1980-January 2016), PubMed (1966-January 2016), and Baidu search engine. After independent quality assessment and data extraction, meta-analysis was conducted using RevMan 5.1 software. RESULTS: Four RCTs and 18 NRCTs were included. When compared with choledochotomy exploration (CE) plus T-tube drainage (TTD) (CE + TTD), CE plus PDC (CE + PDC) and CE + PDC with biliary drainage (BD) (CE + PDC + BD) had a lower rate of postoperative biliary peritonitis (OR = 0.22; 95% CI: 0.06, 0.88; P < 0.05; OR = 0.27; 95% CI: 0.08, 0.84; P < 0.05; respectively) where T-tubes were removed more than 3 weeks. The operative time of CE + PDC was significantly shorter (WMD = -24.82; 95% CI: -27.48, -22.16; P < 0.01) than that of CE + TTD in RCTs. Cystic duct exploration (CDE) plus PDC (CDE + PDC) has a lower rate of postoperative complications (OR = 0.39; 95% CI: 0.23, 0.67; P < 0.01) when compared with CE + PDC. Confluence part micro-incision exploration (CME) plus PDC (CME + PDC) has a lower rate of postoperative bile leakage (OR = 0.17; 95% CI: 0.04, 0.74; P < 0.05) when compared with CE + PDC. CONCLUSION: PDC with other various approaches are better than TTD in the treatment of choledocholithiasis.

Early effects of low dose C ion or x-ray irradiation on peripheral blood lymphocytes of patients with alimentary tract cancer.

The aim of this study was to examine the early effects of low dose (12)C(6+) irradiation or X-ray on peripheral blood lymphocytes (PBL) of patients with alimentary tract cancer and to explore mechanisms that may be involved in an antitumor immune response. We found that the percentage of T lymphocyte subsets, the mRNA expression levels of IL-2 and IFN-γ in PBL, and their protein levels in supernatant were significantly increased 24 hours after exposure to low dose radiation. The effects were more pronounced in the group receiving 0.05Gy (12)C(6+) ion irradiation than the group receiving X-ray irradiation. There was no significant change in the percentage of NK cell subsets and TNF-α production of PBL. Our study suggests that low dose irradiation could alleviate immune suppression caused by tumor burden and that the effect was more pronounced for 0.05Gy high linear energy transfer (LET) (12)C(6+) irradiation.