Robot-Assisted Versus Laparoscopy-Assisted Proximal Gastrectomy for Early Gastric Cancer in the Upper Location: Comparison of Oncological Outcomes, Surgical Stress, and Nutritional Status

A systematic review on the effectiveness of robot-assisted minimally invasive gastrectomy

BACKGROUND

Robot-assisted minimally invasive gastrectomy (RAMIG) is increasingly used as a surgical approach for gastric cancer. This study assessed the effectiveness of RAMIG and studied which stages of the IDEAL-framework (1 = Idea, 2A = Development, 2B = Exploration, 3 = Assessment, 4 = Long-term follow-up) were followed.

METHODS

The Cochrane Library, Embase, Pubmed, and Web of Science were searched for studies on RAMIG up to January 2023. Data collection included the IDEAL-stage, demographics, number of participants, and study design. For randomized controlled trials (RCTs) and long-term studies, data on intra-, postoperative, and oncologic outcomes, survival, and costs of RAMIG were collected and summarized.

RESULTS

Of the 114 included studies, none reported the IDEAL-stage. After full-text reading, 18 (16%) studies were considered IDEAL-2A, 75 (66%) IDEAL-2B, 4 (4%) IDEAL-3, and 17 (15%) IDEAL-4. The IDEAL-stages were followed sequentially (2A-4), with IDEAL-2A studies still ongoing. IDEAL-3 RCTs showed lower overall complications (8.5-9.2% RAMIG versus 17.6-19.3% laparoscopic total/subtotal gastrectomy), equal 30-day mortality (0%), and equal length of hospital stay for RAMIG (mean 5.7-8.5 days RAMIG versus 6.4-8.2 days open/laparoscopic total/subtotal gastrectomy). Lymph node yield was similar across techniques, but RAMIG incurred significantly higher costs than laparoscopic total/subtotal gastrectomy ($13,423-15,262 versus $10,165-10,945). IDEAL-4 studies showed similar or improved overall/disease-free survival for RAMIG.

CONCLUSION

During worldwide RAMIG implementation, the IDEAL-framework was followed in sequential order. IDEAL-3 and 4 long-term studies showed that RAMIG is similar or even better to conventional surgery in terms of hospital stay, lymph node yield, and overall/disease-free survival. In addition, RAMIG showed reduced postoperative complication rates, despite higher costs.

Sentinel Node Navigation Surgery for Early Gastric Cancer: A Narrative Review

Early gastric cancer (EGC) refers to malignant tumor lesions that are limited to the mucosa and submucosa layers, regardless of the presence of lymph node metastasis. Typically, EGC has a low rate of perigastric lymph node metastasis, and long-term survival outcomes are good after radical surgical treatment. The primary objective of surgical treatment for EGC is to achieve functional preservation while ensuring a radical cure. Sentinel node navigation surgery (SNNS) is a surgical technique used in the treatment of EGC. This approach achieves functional preservation by limiting lymph node dissection and performing restrictive gastrectomy guided by intraoperative negative sentinel node (SN) biopsy. Despite the apparent improvement in the detection rate of SN with the emergence of various tracing dyes and laparoscopic fluorescence systems, the oncological safety of SNNS remains a controversial research topic. SNNS, as a true form of stomach preservation surgery that enhances the quality of life, has become a topic of interest in the EGC field. In recent years, scholars from Japan and South Korea have conducted extensive research on the feasibility and safety of SNNS in the treatment of EGC. This article aims to provide reference choices for surgeons treating EGC by reviewing relevant research on SNNS for EGC in recent years.

Robotic Versus Laparoscopic Gastrectomy for Gastric Cancer: A Mega Meta-Analysis

Background

Laparoscopic gastrectomy and robotic gastrectomy are the most widely adopted treatment of choice for gastric cancer. To systematically assess the safety and effectiveness of robotic gastrectomy for gastric cancer, we carried out a systematic review and meta-analysis on short-term and long-term outcomes of robotic gastrectomy.

Methods

In order to find relevant studies on the efficacy and safety of robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) in the treatment of gastric cancer, numerous medical databases including PubMed, Medline, Cochrane Library, Embase, Google Scholar, and China Journal Full-text Database (CNKI) were consulted, and Chinese and English studies on the efficacy and safety of RG and LG in the treatment of gastric cancer published from 2012 to 2022 were screened according to inclusion and exclusion criteria, and a meta-analysis was conducted using RevMan 5.4 software.

Results

The meta-analysis inlcuded 48 literatures, with 20,151 gastric cancer patients, including 6,175 in the RG group and 13,976 in the LG group, respectively. Results of our meta-analysis showed that RG group had prololonged operative time (WMD = 35.72, 95% CI = 28.59–42.86, P < 0.05) (RG: mean ± SD = 258.69 min ± 32.98; LG: mean ± SD = 221.85 min ± 31.18), reduced blood loss (WMD = −21.93, 95% CI = −28.94 to −14.91, P < 0.05) (RG: mean ± SD = 105.22 ml ± 62.79; LG: mean ± SD = 127.34 ml ± 79.62), higher number of harvested lymph nodes (WMD = 2.81, 95% CI = 1.99–3.63, P < 0.05) (RG: mean ± SD = 35.88 ± 4.14; LG: mean ± SD = 32.73 ± 4.67), time to first postoperative food intake shortened (WMD = −0.20, 95% CI = −0.29 to −0.10, P < 0.05) (RG: mean ± SD = 4.5 d ± 1.94; LG: mean ± SD = 4.7 d ± 1.54), and lower length of postoperative hospital stay (WMD = −0.54, 95% CI = −0.83 to −0.24, P < 0.05) (RG: mean ± SD = 8.91 d ± 6.13; LG: mean ± SD = 9.61 d ± 7.74) in comparison to the LG group. While the other variables, for example, time to first postoperative flatus, postoperative complications, proximal and distal mar gin, R₀ resection rate, mortality rate, conversion rate, and 3-year overall survival rate were all found to be statistically similar at P > 0.05.

Conclusions

In the treatment of gastric cancer, robotic gastrectomy is a safe and effective procedure that has both short- and long-term effects. To properly evaluate the advantages of robotic surgery in gastric cancer, more randomised controlled studies with rigorous research methodologies are needed.

Pooled analysis of the oncological outcomes in robotic gastrectomy versus laparoscopic gastrectomy for gastric cancer

Aim:

Robotic gastrectomy (RG) is more and more widely used in the treatment of gastric cancer. However, the long-term oncological outcomes of RG have not been well evaluated. The aim of this study was to evaluate the long-term oncological outcomes of RG and laparoscopic gastrectomy (LG) in the treatment of gastric cancer.

Materials and Methods:

PubMed, China National Knowledge Infrastructure, Cochrane Library and EMBASE electronic databases were searched until August 2019. Eligible studies were analysed for comparison of oncological outcomes between RG and LG in patients with gastric cancer.

Results:

Eleven retrospective comparative studies, which included 1347 (32.52%) patients in the RG group and 2795 (67.48%) patients in the LG group, were selected for the analysis. Meta-analysis of the 11 included studies showed that there was no statistically significant difference in the OS between the RG and LG groups (hazard ratios [HRs] = 0.97, 95% confidence intervals [CIs] = 0.80–1.19, P = 0.80). Six studies evaluated disease-free survival (DFS), and pooled analysis showed that there was no statistically significant difference in DFS between RG group and LG group (HR = 0.94, 95% CIs = 0.72–1.23, P = 0.65). According to the odds ratio (OR) analysis, there was no significant difference in 3-year OS, 5-year OS, 3-year DFS and 5-year DFS between the RG and LG groups. Nine articles reported the recurrence rate, and the meta-analysis showed that there was no statistically significant difference between the RG and LG groups (OR = 0.88, 95% CIs = 0.69–1.12, P = 0.31).

Conclusions:

This meta-analysis indicated that the long-term oncological outcomes in the RG group were similar to that in the LG group.

Research on target feature extraction and location positioning with machine learning algorithm

The accurate positioning of target is an important link in robot technology. Based on machine learning algorithm, this study firstly analyzed the location positioning principle of binocular vision of robot, then extracted features of the target using speeded-up robust features (SURF) method, positioned the location using Back Propagation Neural Networks (BPNN) method, and tested the method through experiments. The experimental results showed that the feature extraction of SURF method was fast, about 0.2 s, and was less affected by noise. It was found from the positioning results that the output position of the BPNN method was basically consistent with the actual position, and errors in X, Y and Z directions were very small, which could meet the positioning needs of the robot. The experimental results verify the effectiveness of machine learning method and provide some theoretical support for its further promotion and application in practice.

Robotic versus laparoscopic gastrectomy for gastric cancer: The largest meta-analysis

BACKGROUND

Minimally invasive surgery (MIS) has been increasingly used in the treatment of gastric cancer (GC). Laparoscopic gastrectomy (LG) has shown several advantages over open surgery in dealing with GC, although it is still considered a demanding procedure. Robotic gastrectomy (RG) is now being employed with increased frequency worldwide and has been reported to overcome some limitations of conventional LG. The aim of this updated meta-analysis is to compare surgical and oncological outcomes of RG versus LG for gastric cancer.

MATERIALS AND METHODS

A systematic review and meta-analysis was conducted using the PubMed, MEDLINE and Cochrane library database of published studies comparing RG and LG up to March 2020. The evaluated end-points were intra-operative, post-operative and oncological outcomes. Dichotomous data were calculated by odds ratio (OR) and continuous data were calculated by mean difference (MD) with 95% confidence intervals (95% CI), and a random-effect model was always applied.

RESULTS

Forty retrospective studies describing 17,712 patients met the inclusion criteria. With respect to surgical outcomes, robotic compared with laparoscopic gastrectomy was associated with higher operating time [MD 44.73, (95%CI 36.01, 53.45) p < 0.00001] and less intraoperative blood loss [MD -18.24, (95%CI -25.21, -11.26) p < 0.00001] and lower rate of surgical complication in terms of Dindo-Clavien ≥ 3 classification [OR 0.66, (95%CI 0.49, 0.88) p = 0.005]. With respect to oncological outcomes, the RG group showed a significantly increased mean number of retrieved lymph nodes [MD 1.84, (95%CI 0.84, 2.84) p = 0.0003], but mean proximal and distal resection margin distance and the recurrence rate were not significantly different between the two approaches.

CONCLUSIONS

With respect to safety, technical feasibility and oncological adequacy, robotic and laparoscopic groups were comparable, although the robotic approach seems to achieve better short-term surgical outcomes. Moreover, a higher rate of retrieved lymph nodes was observed in the RG group.

Effects of reconstruction techniques after proximal gastrectomy: a systematic review and meta-analysis

BACKGROUND

Additional studies comparing several reconstruction methods after proximal gastrectomy have been published; of note, it is necessary to update systematic reviews and meta-analysis from the current evidence-based literature.

AIM

To expand the current knowledge on feasibility and safety, and also to analyze postoperative outcomes of several reconstructive techniques after proximal gastrectomy.

METHODS

PubMed, Google Scholar, and Medline databases were searched for original studies, and relevant literature published between the years 1966 and 2019 concerning various reconstructive techniques on proximal gastrectomy were selected. The postoperative outcomes and complications of the reconstructive techniques were assessed. Meta-analyses were performed using Rev-Man 5.0. A total of 29 studies investigating postoperative outcomes of double tract reconstruction, jejunal pouch interposition, jejunal interposition, esophagogastrostomy, and double flap reconstruction were finally selected in the quantitative analysis.

RESULT

Pooled incidences of reflux esophagitis for double tract reconstruction, jejunal pouch interposition, jejunal interposition esophagogastrostomy, and double flap reconstruction were 8.6%, 13.8%, 13.8%, 19.3%, and 8.9% respectively. Meta-analysis showed a decreased length of hospital in the JI group as compared to the JPI group (heterogeneity: Chi2 = 1.34, df = 1 (P = 0.25); I2 = 26%, test for overall effect: Z = 2.22 (P = 0.03). There was also a significant difference between JI and EG in length of hospital stay with heterogeneity: Chi2 = 1.40, df = 3 (P = 0.71); I2 = 0%, test for overall effect: Z = 5.04 (P < 0.00001). Operative time was less in the EG group as compared to the JI group (heterogeneity: Chi2 = 31.09, df = 5 (P < 0.00001); I2 = 84%, test for overall effect: Z = 32.35 (P < 0.00001).

CONCLUSION

Although current reconstructive techniques present excellent anti-reflux efficacy, the optimal reconstructive method remains to be determined. The double flap reconstruction proved to lower the rate of complication, but the DTR, JI, JPI, and EG groups showed higher incidence of complications in anastomotic leakage, anastomotic stricture, and residual food. In the meta-analysis result, the complications between the JI, JPI, and EG were comparable but the EG group showed to have better postoperative outcomes concerning the operative time, blood loss, and length of hospital stay.

LncRNA THOR increases the stemness of gastric cancer cells via enhancing SOX9 mRNA stability

This work aims to explore the roles and mechanisms of long non coding RNA (lncRNA) THOR in regulating the stemness of gastric cancer cells. RNA-sequencing combined with quantitative real-time PCR (qRT-PCR) indicated that lncRNA THOR level was significantly upregulated in gastric cancer tissues compared with that in normal adjacent tissues. Knockdown of THOR attenuated the stemnness of gastric cancer cells, evident by the decrease of stemness markers expression and capacity of cells spheroid formation. Further RNA-sequencing combined with qRT-PCR and western blot analysis demonstrated that expression of transcriptional factor SOX9 was remarkably decreased in gastric cancer cells with THOR stable knockdown. Additionally, RNA immunoprecipitation (RIP) combined with luciferase reporter assay revealed that THOR directly bound to SOX9 3' untranslated region (3'UTR), but not its 5'UTR or coding area. Notably, overexpression of SOX9 rescued THOR knockdown-mediated inhibition on the stemness of gastric cancer cells. Thus, our results suggest that THOR could potentiate the stemness of gastric cancer cells via directly binding to SOX9 3'UTR.