Background
Robotic gastrectomy (RG) has increased since being covered by universal health insurance in 2018. However, to ensure patient safety the operating surgeon and facility must meet specific ...requirements. We aimed to determine whether RG has been safely implemented under the requirements for universal health insurance in Japan.
Methods
Data of consecutive patients with primary gastric cancer who underwent minimally invasive total or distal gastrectomy—performed by a surgeon certified by the Japan Society for Endoscopic Surgery (JSES) endoscopic surgical skill qualification system (ESSQS) between October 2018 and December 2019—were extracted from the gastrointestinal surgery section of the National Clinical Database (NCD). The primary outcome was morbidity over Clavien–Dindo classification grade IIIa. Patient demographics and hospital volume were matched between RG and laparoscopic gastrectomy (LG) using propensity score-matched analysis (PSM), and the short-term outcomes of RG and LG were compared.
Results
After PSM, 2671 patients who underwent RG and 2671 who underwent LG were retrieved (from a total of 9881), and the standardized difference of all the confounding factors reduced to 0.07 or less. Morbidity rates did not differ between the RG and LG patients (RG, 4.9% vs. LG, 3.9%;
p
= 0.084). No difference was observed in 30-day mortality (RG, 0.2% vs. LG, 0.1%;
p
= 0.754). The reoperation rate was greater following RG (RG, 2.2% vs. LG, 1.2%;
p
= 0.004); however, the duration of postoperative hospitalization was shorter (RG, 10 8–13 days vs. LG, 11 9–14 days;
p
< 0.001).
Conclusions
Insurance-covered RG has been safely implemented nationwide.
Background
Gastric cancer (GC) has been classified based on molecular profiling like The Cancer Genome Atlas (TCGA) and Asian Cancer Research Group (ACRG), and attempts have been made to establish ...therapeutic strategies based on these classifications. However, it is difficult to predict the survival according to these classifications especially in radically resected patients. We aimed to establish a new molecular classification of GC which predicts the survival in patients undergoing radical gastrectomy.
Methods
The present study included 499 Japanese patients with advanced GC undergoing radical (R0/R1) gastrectomy. Whole-exome sequencing, panel sequencing, and gene expression profiling were conducted (High-tech Omics-based Patient Evaluation Project HOPE). We classified patients according to TCGA and ACRG subtypes, and evaluated the clinicopathologic features and survival. Then, we attempted to classify patients according to their molecular profiles associated with biological features and survival (HOPE classification).
Results
TCGA and ACRG classifications failed to predict the survival. In HOPE classification, hypermutated (HMT) tumors were selected first as a distinctive feature, and T-cell-inflamed expression signature-high (TCI) tumors were then extracted. Finally, the remaining tumors were divided by the epithelial-mesenchymal transition (EMT) expression signature. HOPE classification significantly predicted the disease-specific and overall survival (
p
< 0.001 and 0.020, respectively). HMT + TCI showed the best survival, while EMT-high showed the worst survival. The HOPE classification was successfully validated in the TCGA cohort.
Conclusions
We established a new molecular classification of gastric cancer that predicts the survival in patients undergoing radical surgery.
Background
Robotic gastrectomy (RG) has been developed to address the drawbacks of laparoscopic gastrectomy (LG); however, whether or not RG is superior to conventional LG remains to be seen. The ...present study aimed to clarify the impact of RG on clinical stage I/II gastric cancer patients.
Methods
The present study included 1208 patients with clinical stage I/II gastric cancer who had minimally invasive gastrectomy from January 2012 to March 2020 at the Shizuoka Cancer Center. The short- and long-term outcomes of RG and LG were compared after propensity score matching.
Results
This study involved 835 LG and 345 RG patients. After propensity score matching, there were 342 patients each in the RG and LG groups, with an improved balance of confounding factors between the two groups. RG was associated with a significantly longer operative time and lower amylase concentration in the drainage fluid on the first postoperative day than LG. Furthermore, the incidence of intra-abdominal infectious complications in the RG was lower than that in the LG (4.4% vs. 9.4%;
P
= 0.015). The survival of the RG and LG groups was equivalent.
Conclusions
RG reduced the risk of intra-abdominal infectious complications in comparison with LG in the propensity score-matched analysis. Patients treated by the two approaches showed equivalent survival.
Background
Increasing numbers of patients are treated by robotic distal gastrectomy (RDG); however, it remains unclear whether RDG is clinically comparable with conventional laparoscopic distal ...gastrectomy (LDG). This study aimed to clarify the feasibility of RDG from safety aspects.
Methods
The study included 109 cT1 gastric cancer patients who underwent RDG at Shizuoka Cancer Center from January 2012 to April 2015. Short-term outcomes were compared with 160 cT1 gastric cancer patients who underwent LDG during the same period.
Results
Patient characteristics were well matched. The RDG patients experienced longer operative times (323 min) than LDG patients (285 min;
P
< 0.001), although all other surgical outcomes were comparable between the groups. Drain amylase levels on POD 1 were significantly lower in the RDG group compared to LDG cases (median 452 U/L and 892 U/L;
P
< 0.001). The incidence of all complications was similar across the study patients, although intra-abdominal infectious complications tended to be lower in the RDG group than in the LDG group (2.8 and 8.1%;
P
= 0.112).
Conclusions
RDG was comparable to LDG in terms of feasibility for cT1 gastric cancer. RDG has the potential to reduce pancreas damage and thus to decrease intra-abdominal infectious complications.
Background
A replaced left hepatic artery (RLHA) arising from the left gastric artery (LGA) is occasionally encountered during laparoscopic gastrectomy. Although the RLHA is usually divided at the ...root level as RLHA preservation might result in inadequate lymph node dissection, blood flow disruption by RLHA division may lead to hepatic ischemia. To date, there is no consensus on RLHA preservation. Thus, we aimed to evaluate the efficacy of RLHA preservation by investigating the short-term outcomes of patients with RLHA who underwent laparoscopic distal gastrectomy (LDG).
Methods
A total of 106 patients with an aberrant LHA from the LGA were identified as having gastric cancer and underwent LDG from 2012 to 2018. Finally, 55 patients were retrospectively diagnosed with RLHA by preoperative computed tomography and included in this study. Patients were classified into the divided (
n
= 18) or preserved (
n
= 37) group. Clinicopathological factors and surgical outcomes were compared between the two groups.
Results
The RLHA preservation rate in patients who had been preoperatively diagnosed with RLHA was 88%. No significant difference was found in the number of harvested lymph nodes between the groups. The incidence of hepatic infarction was significantly higher in the divided group (16.7% vs. 0%,
p
= 0.031). Moreover, RLHA division caused postoperative transaminase elevation and was an independent risk factor for postoperative transaminase elevation (odds ratio: 55.8,
p
< 0.001).
Conclusions
Surgical procedures of RLHA preservation reduced postoperative transaminase elevation and hepatic infarction in patients who underwent LDG. Surgeons should confirm the RLHA preoperatively and preserve it to prevent hepatic damage.
Background
Phase III trials have shown the non-inferiority of minimally invasive distal gastrectomy (MIDG) comparison with open distal gastrectomy (ODG) in patients with gastric cancer; however, it ...remains unclear whether MIDG is also effective in the elderly. This study aimed to clarify the efficacy of MIDG in elderly gastric cancer patients.
Patients and methods
This study included 316 patients older than 75 years with clinical stage I/IIA gastric cancer who underwent distal gastrectomy from August 2008 to December 2016 at the Shizuoka Cancer Centre. The long-term outcomes between MIDG and ODG were compared after propensity score matching.
Results
After propensity score matching, there were 97 patients each in the MIDG and ODG groups, with an improved balance of confounding factors between the two groups. MIDG was associated with significantly longer operative time and a lower level of blood loss than ODG. The incidence of complications was comparable between the two groups. Survival outcomes were better in the MIDG group than in the ODG group (overall survival;
P
= 0.034, relapse-free survival;
P
= 0.027). In the multivariable analysis, ODG hazard ratio (HR) 1.971,
P
= 0.046, being 80 years or older (HR 2.285,
P
= 0.018), male sex (HR 2.428, 95%
P
= 0.024), and poor physical status (HR 2.324,
P
= 0.022) were identified as independent prognostic factors for overall survival.
Conclusions
We found that MIDG showed better efficacy than ODG in elderly gastric cancer patients. MIDG is an acceptable option for elderly patients.
Introduction
The outcomes of robotic gastrectomy (RG) for gastric cancer remain unclear due to a lack of prospective studies. We had previously designed and conducted a prospective phase II study of ...RG that showed favorable short-term outcomes. Herein, we aimed to determine the long-term outcomes of RG for clinical stage I gastric cancer.
Patients and methods
This single-center, prospective phase II study enrolled patients with clinical stage I gastric cancer undergoing RG. The survival outcomes, which were the secondary endpoints of the study, were evaluated.
Results
Between December 2012 and April 2015, 120 patients were enrolled in this study. The 5-year overall survival (OS) was 96.7% (95% confidence interval CI 91.5–98.7%). The 5-year recurrence-free (RFS) and disease-specific survival (DSS) rates were 96.7% (95% CI 91.5–98.7%) and 99.2% (95% CI 94.3–99.9%), respectively. When confining the analysis to distal and pylorus-preserving gastrectomy, the 5-year OS, RFS, and DSS were 98.1% (95% CI 92.7–99.5%), 98.1% (95% CI 92.7–99.5%), and 100%, respectively. Only one patient died due to relapse of gastric cancer, while three died from other causes.
Conclusions
Long-term outcomes of RG was comparable to those of open and laparoscopic gastrectomy when the surgeries were performed by experienced surgeons in a high-volume center.
Background
Per-oral endoscopic myotomy (POEM) is an endoscopic procedure whereby the esophageal muscle is incised in order to lower the lower esophageal sphincter (LES) pressure. Since the time it ...was first performed in 2008 and subsequently reported on in 2010 by Inoue et al., POEM has been shown to be safe and effective for straight type of achalasia. On the other hand, the efficacy of POEM had been controversial for patients with achalasia of the sigmoid type, in which a high LES pressure is accompanied by morphological changes, including dilation, acute angulation, and rotation. The aim of this study is to evaluate the safety and efficacy of POEM in patients with sigmoid type of achalasia.
Methods
Between May 2015 and December 2017, 16 patients with a sigmoid type of achalasia underwent POEM in our institute. The POEM procedure was the same as that for the straight type of achalasia. The double-scope technique was used to check the distal end of the submucosal tunnel from the gastric side. The primary endpoint was improvement of Eckardt score at 2 months after POEM. The secondary endpoints comprised operating time, change in the esophageal angulation, and adverse events.
Results
All patients underwent POEM without severe adverse events. The respective parameters before and after POEM significantly differed in terms of mean (SD) Eckardt score 4.9 (2.0) vs. 0.4 (0.6),
p
< 0.01, LES pressure 19.4 (10.2) vs. 9.2 (6.4),
p
< 0.01, and integrated relaxation pressure 17.6 (9.2) vs. 7.9 (5.5),
p
< 0.01. The average operation time was 94.7 ± 31.4 min. The average esophageal angulation was 88.4° ± 23.1° before POEM and 109.5° ± 16.7° after POEM (
p
< 0.01). Four patients had postoperative complications that were treated conservatively.
Conclusions
POEM can improve both LES pressure and esophageal angulation in patients with sigmoid achalasia.
Graphic abstract
Background
Gallstones are known to occur quite frequently after gastrectomy. Most of the studies about postoperative cholelithiasis have focused on open gastrectomy, whereas laparoscopic gastrectomy ...has recently gained popularity as a type of minimally invasive surgery (MIS). Hence, the efficacy of MIS in preventing post-gastrectomy gallstone formation remains to be elucidated. This study aimed to evaluate the risk of gallstone formation after MIS for clinical stage I/IIA gastric cancer.
Methods
A total of 1166 patients undergoing gastrectomy for clinical stage I/IIA gastric cancer between 2009 and 2016 were included in this study. Gallstones were detected on abdominal ultrasound and/or computed tomography. Multivariate logistic regression analysis was used to determine factors associated with postoperative gallstone formation.
Results
Gallstone formation was observed in 174 patients (15%), of whom 22 (2%) experienced symptomatic cholelithiasis. In multivariate analysis, the following were identified as risk factors for post-gastrectomy gallstone formation: open approach with an odds ratio (OR) of 1.670 and a 95% confidence interval (CI) of 1.110–2.510 (
P
= 0.014), older age (OR 1.880; 95% CI 1.290–2.730;
P
< 0.001), high body mass index (OR 1.660; 95% CI 1.140–2.420;
P
= 0.008), Roux-en-Y (RY) reconstruction (OR 1.770; 95% CI 1.230–2.530;
P
= 0.002), hepatic branch vagotomy (OR 1.600; 95% CI 1.050–2.440;
P
= 0.029), and intra-abdominal infectious complications (OR 3.040; 95% CI 1.680–5.490;
P
< 0.001).
Conclusion
Our study suggested that MIS along with the preservation of the hepatic vagus nerve and non-RY reconstruction could help prevent post-gastrectomy gallstone development.
Background
Studies to identify predictive biomarkers of adjuvant chemotherapy with S-1 after gastrectomy in Stage II/III gastric cancer patients have been done; however, more clarity and ...understanding are needed. Our aim in the present study was to identify biomarkers predicting benefit due to S-1 adjuvant chemotherapy using comprehensive gene expression analysis.
Methods
We retrospectively analyzed 102 patients receiving adjuvant chemotherapy with S-1 and 46 patients not receiving S-1 adjuvant chemotherapy after gastrectomy for gastric cancer treatment between January 2014 and December 2016. Hierarchical clustering analysis was performed based on the gene expression data obtained using cDNA microarray. Differentially expressed genes (DEGs) were identified using thresholds of absolute fold changes of > 4.0 and a false discovery rate
P
value of < 0.01. Gene Ontology (GO) analysis and GO network visualization were performed using the ClueGO app in Cytoscape.
Results
Hierarchical clustering analysis in patients treated with S-1 adjuvant chemotherapy revealed two clusters with favorable and unfavorable survival outcomes. We identified 147 upregulated DEGs and 192 downregulated DEGs in the favorable outcome group. GO analysis to identify significantly upregulated genes showed enrichment in immune-related genes and GO terms. Upregulation of these immune-related genes was not associated with survival in patients not receiving S-1 adjuvant chemotherapy.
Conclusions
The upregulation and enrichment of immune-related genes and GO terms may be predictive biomarkers in patients who would benefit from adjuvant S-1 chemotherapy to treat Stage II/III gastric cancer.