To determine the safety of laparoscopy-assisted distal gastrectomy (LADG) compared with open distal gastrectomy (ODG) in patients with clinical stage I gastric cancer in Korea.
There is still a lack ...of large-scale, multicenter randomized trials regarding the safety of LADG.
A large-scale, phase 3, multicenter, prospective randomized controlled trial was conducted. The primary end point was 5-year overall survival. Morbidity within 30 postoperative days and surgical mortality were compared to evaluate the safety of LADG as a secondary end point
: A total of 1416 patients were randomly assigned to the LADG group (n = 705) or the ODG group (n = 711) between February 1, 2006, and August 31, 2010, and 1384 patients were analyzed for modified intention-to-treat analysis (ITT) and 1256 were eligible for per protocol (PP) analysis (644 and 612, respectively). In the PP analysis, 6 patients (0.9%) needed open conversion in the LADG group. The overall complication rate was significantly lower in the LADG group (LADG vs ODG; 13.0% vs 19.9%, P = 0.001). In detail, the wound complication rate of the LADG group was significantly lower than that of the ODG group (3.1% vs 7.7%, P < 0.001). The major intra-abdominal complication (7.6% vs 10.3%, P = 0.095) and mortality rates (0.6% vs 0.3%, P = 0.687) were similar between the 2 groups. Modified ITT analysis showed similar results with PP analysis.
LADG for patients with clinical stage I gastric cancer is safe and has a benefit of lower occurrence of wound complication compared with conventional ODG.
microRNAs (miRNAs) play integral roles in diverse processes including tumorigenesis. miRNA gene loci are often found in close conjunction, and such clustered miRNA genes are transcribed from a common ...promoter to generate polycistronic primary transcript. The primary transcript (pri-miRNA) is then processed by two RNase III proteins to release the mature miRNAs. Although it has been speculated that the miRNAs in the same cluster may play related biological functions, this has not been experimentally addressed. Here we report that the miRNAs in two clusters (miR-106b∼93 ∼ 25 and miR-222 ∼ 221) suppress the Cip/Kip family members of Cdk inhibitors (p57Kip2, p21Cip1 and p27Kip1). We show that miR-25 targets p57 through the 3′-UTR. Furthermore, miR-106b and miR-93 control p21 while miR-222 and miR-221 regulate both p27 and p57. Ectopic expression of these miRNAs results in activation of Cdk2 and facilitation of G1/S phase transition. Consistent with these results, both clusters are abnormally upregulated in gastric cancer tissues compared to the corresponding normal tissues. Ectopic expression of miR-222 cluster enhanced tumor growth in the mouse xenograft model. Our study demonstrates the functional associations between clustered miRNAs and further implicates that effective cancer treatment may require a combinatorial approach to target multiple oncogenic miRNA clusters.
The aim of this study was to combine clinicopathologic variables associated with overall survival after gastric resection with D2 lymphadenectomy (D2 gastrectomy) for gastric cancer into a prediction ...nomogram.
We retrospectively analyzed 7,954 patients who underwent D2 gastrectomy for gastric cancer at Seoul National University Hospital (SNUH) in Seoul, Korea. Two thirds of the patients were randomly assigned to the training set (n = 5,300), and one third were assigned to the validation set (n = 2,654). Multivariate analysis by Cox proportional hazards regression was performed using the training set, and the nomogram was constructed. Discrimination and calibration were performed using the SNUH validation set. Additional external validation was performed using the data set (n = 2,500) from Cancer Institute Ariake Hospital (CIAH) in Tokyo, Japan.
The multivariate Cox model identified age at diagnosis, sex, location, depth of invasion, number of metastatic lymph nodes, and number of examined lymph nodes as covariates associated with survival. In the SNUH validation set, the nomogram exhibited superior discrimination power compared with the seventh American Joint Committee on Cancer TNM classification (Harrell's C-index, 0.78 v 0.69, respectively; P < .001). Calibration of the nomogram predicted survival corresponding closely with the actual survival. In the CIAH validation set, discrimination was good (C-index, 0.79), and the predicted survival was within a 10% margin of ideal nomogram.
We developed a nomogram predicting 5- and 10-year overall survival after D2 gastrectomy for gastric cancer. Validation using the SNUH and CIAH data sets revealed good discrimination and calibration, suggesting good clinical utility. The nomogram improved individualized predictions of survival.
In this study, position-independent geometric errors, including offset errors and squareness errors of rotary axes of a five-axis machine tool are measured using a double ball-bar and are verified ...through compensation. In addition, standard uncertainties of measurement results are calculated to establish their confidence intervals. This requires two measurement paths for each rotary axis, which are involving control of single rotary axis during measurement. So, the measurement paths simplify the measurement process, and reduce measurement cost including less operator effort and measurement time. Set-up errors, which are inevitable during the installation of the balls, are modeled as constants. Their effects on the measurement results are investigated to improve the accuracy of the measurement result. A novel fixture consisting of flexure hinges and two pairs of bolts is used to minimize set-up error by adjusting the ball's position located at the tool nose. Simulation is performed to check the validation of measurement and to analyze the standard uncertainties of the measurement results. Finally, the position-independent geometric errors of the five-axis machine tool (involving a rotary axis and a trunnion axis) are measured using proposed method.
•PIGEs of a five-axis machine tool are measured using a double ball-bar.•Simple measurement paths are developed to decrease measurement cost.•Set-up errors are investigated and minimized by using novel fixture.•Measurement uncertainty of measured PIGEs is established for confidence interval.
Gastric cancer (GC) remains difficult to cure due to heterogeneity in a clinical challenge and the molecular mechanisms underlying this disease are complex and not completely understood. Accumulating ...evidence suggests that microRNAs (miRNAs) play an important role in GC, but the role of specific miRNAs involved in this disease remains elusive. We performed next generation sequencing (NGS)-based whole-transcriptome profiling to discover GC-specific miRNAs, followed by functional validation of results.
NGS-based miRNA profiles were generated in matched pairs of GCs and adjacent normal mucosa (NM). Quantitative RT-PCR validation of miR-29c expression was performed in 274 gastric tissues, which included two cohorts of matched GC and NM specimens. Functional validation of miR-29c and its gene targets was undertaken in cell lines, as well as K19-C2mE and K19-Wnt1/C2mE transgenic mice.
NGS analysis revealed four GC-specific miRNAs. Among these, miR-29c expression was significantly decreased in GC versus NM tissues (p<0.001). Ectopic expression of miR-29c mimics in GC cell lines resulted in reduced proliferation, adhesion, invasion and migration. High miR-29c expression suppressed xenograft tumour growth in nude mice. Direct interaction between miR-29c and its newly discovered target, ITGB1, was identified in cell lines and transgenic mice. MiR-29c expression demonstrated a stepwise decrease in wild type hyperplasia-dysplasia cascade in transgenic mice models of GC.
MiR-29c acts as a tumour suppressor in GC by directly targeting ITGB1. Loss of miR-29c expression is an early event in the initiation of gastric carcinogenesis and may serve as a diagnostic and therapeutic biomarker for patients with GC.
The aim of the study was to evaluate the short-term outcomes of KLASS-02-RCT, a multicenter randomized controlled trial comparing laparoscopic distal gastrectomy (LDG) with D2 lymphadenectomy with ...open distal gastrectomy (ODG).
Although several benefits of laparoscopic gastric cancer surgery have been reported, strong evidence is still limited, especially in locally advanced gastric cancer which requires extensive lymph node dissection.
Enrollment criteria included histologically confirmed cT2-4a and N0-1 gastric adenocarcinoma. Thirty-day morbidity, 90-day mortality, postoperative pain, and recovery were compared between LDG and ODG groups.
A total of 1050 patients were randomly assigned to LDG (n = 526) or ODG group (n = 524) between November 2011 and April 2015. After excluding patients who received bypass or no surgery, 1011 patients were analyzed as actual treatment group. Mean number of totally retrieved lymph nodes was similar in both groups (LDG = 46.6 vs ODG = 47.4, P = 0.451). Early morbidity rate was significantly lower after LDG (16.6%) than after ODG (24.1%; P = 0.003). Postoperative analgesics use and patients' reported pain score were significantly lower after LDG. First day of flatus was earlier after LDG (3.5 vs 3.7 d, P = 0.025) and postoperative hospital stay was shorter in LDG group (8.1 vs 9.3 d, P = 0.005). Ninety days' mortality rate was similar in both groups (LDG = 0.4% vs ODG = 0.6%, P = 0.682).
Laparoscopic distal gastrectomy with D2 lymphadenectomy for locally advanced gastric cancer shows benefits in terms of lower complication rate, faster recovery, and less pain compared with open surgery.
Radical gastrectomy with extended lymph node dissection is standard for gastric cancer.1,2 The extent of lymph node dissection is defined as D1 for the perigastric area, whereas D2 lymph node ...dissection comprises tissue surrounding the next level of lymphatic vessels, including the hepatic artery proper, common hepatic artery, splenic vessels, and splenic hilum.1 Radical D2-lymphadenectomy for advanced gastric cancer had previously been accepted as the surgical standard in Japan and Korea, and the generalisability of this technique was confirmed by a Dutch trial.3 Besides evidence for the extent of standardised lymphadenectomy, surgeons have been concerned about potential spillage of cancer cells from the lymphatic vessels into the peritoneal cavity during surgery, which could lead to metastatic disease after surgery, especially in patients with advanced-stage cancer. ...in gastric cancer surgery, not only the extent of lymph node dissection (D2 or D1), but also the technique by which it is done (avoidance of cell spillage from the lymphatics and lumen) is of importance. Additionally, intraoperative visualisation of lymphatic channels by near infra-red camera with indocyanine green fluorescence can provide a more effective and safe method of lymph node dissection.7 Other efforts are focused on cancer imaging technology to guide the extent of surgery using cancer-specific tracers.
Summary Background D2 gastrectomy is recommended in US and European guidelines, and is preferred in east Asia, for patients with resectable gastric cancer. Adjuvant chemotherapy improves patient ...outcomes after surgery, but the benefits after a D2 resection have not been extensively investigated in large-scale trials. We investigated the effect on disease-free survival of adjuvant chemotherapy with capecitabine plus oxaliplatin after D2 gastrectomy compared with D2 gastrectomy only in patients with stage II–IIIB gastric cancer. Methods The capecitabine and oxaliplatin adjuvant study in stomach cancer (CLASSIC) study was an open-label, parallel-group, phase 3, randomised controlled trial undertaken in 37 centres in South Korea, China, and Taiwan. Patients with stage II–IIIB gastric cancer who had had curative D2 gastrectomy were randomly assigned to receive adjuvant chemotherapy of eight 3-week cycles of oral capecitabine (1000 mg/m2 twice daily on days 1 to 14 of each cycle) plus intravenous oxaliplatin (130 mg/m2 on day 1 of each cycle) for 6 months or surgery only. Block randomisation was done by a central interactive computerised system, stratified by country and disease stage. Patients, and investigators giving interventions, assessing outcomes, and analysing data were not masked. The primary endpoint was 3 year disease-free survival, analysed by intention to treat. This study reports a prespecified interim efficacy analysis, after which the trial was stopped after a recommendation by the data monitoring committee. The trial is registered at ClinicalTrials.gov ( NCT00411229 ). Findings 1035 patients were randomised (520 to receive chemotherapy and surgery, 515 surgery only). Median follow-up was 34·2 months (25·4–41·7) in the chemotherapy and surgery group and 34·3 months (25·6–41·9) in the surgery only group. 3 year disease-free survival was 74% (95% CI 69–79) in the chemotherapy and surgery group and 59% (53–64) in the surgery only group (hazard ratio 0·56, 95% CI 0·44–0·72; p<0·0001). Grade 3 or 4 adverse events were reported in 279 of 496 patients (56%) in the chemotherapy and surgery group and in 30 of 478 patients (6%) in the surgery only group. The most common adverse events in the intervention group were nausea (n=326), neutropenia (n=300), and decreased appetite (n=294). Interpretation Adjuvant capecitabine plus oxaliplatin treatment after curative D2 gastrectomy should be considered as a treatment option for patients with operable gastric cancer. Funding F Hoffmann-La Roche and Sanofi-Aventis.
Background
Stratification of patients who undergo curative resection for early gastric cancer (EGC) is warranted due to the heterogeneity in the risk of developing extragastric recurrence (EGR). ...Therefore, we aimed to stratify the need for postoperative surveillance for EGR detection in patients with EGC by developing a model for predicting EGR-free survival.
Methods
This retrospective cohort study included patients who underwent postoperative surveillance after curative resection of EGC (
n
= 4149). Cox proportional hazard models were used to identify predictors to build a model for predicting EGR-free survival. Bootstrap-corrected c-index and calibration plots were used for internal and external (
n
= 2148) validations.
Results
A risk-scoring system was constructed using variables significantly associated with EGR-free survival: pathologic T stage (pT1bsm1, hazard ratio HR 4.928; pT1bsm2, HR 5.235; pT1bsm3, HR 7.748) and N stage (pN1, HR 4.056; pN2, HR 9.075; pN3, HR 30.659). Patients were dichotomized into a very-low-risk group or a low-or-greater-risk group. The 5-year EGR-free survival rates differed between the two groups (99.9 vs. 97.3%). The discriminative performance of the model was 0.851 (Uno’s c-index) and 0.751 in the internal and external cohorts, respectively. The calibration slope was 0.916 and 1.131 in the internal and external cohorts, respectively.
Conclusions
Our model for predicting EGR-free survival based on the pathologic T and N stages may be useful for stratifying patients who have undergone curative surgery for EGC. The results suggest that patients in the very-low-risk group may be spared from postoperative surveillance considering their extremely high EGR-free survival rate.
Objective
This study applied network analyses to illustrate patterns of associations between cancer‐related physical and psychological symptoms (CPPS) and quality of life (QOL) before and after ...surgery.
Methods
Participants consisted of 256 gastric cancer patients admitted for curative section surgery at the surgical department in a teaching hospital in Korea between May 2016 and November 2017. Participants completed the survey, including MD Anderson Symptom Inventory, Hospital Anxiety and Depression Scale, and Functional Assessment of Cancer Therapy‐Gastric Cancer before surgery (T0), 1 week after surgery (T1), and 3–6 months after surgery (T2).
Results
Three networks featured several salient connections with varying magnitudes between CPPS and QOL across all time points. Particularly, anxiety was tightly connected to emotional wellbeing (EWB) across all time points and physical wellbeing (PWB) at T1. On the other hand, depression was connected to functional wellbeing at T0 and T2, gastric cancer concerns (CS) at T1, and PWB at T2. Distress and sadness were the most central symptoms in the three networks. Other central symptoms included shortness of breath at T0, fatigue at T0 and T1, and PWB and CS at T2. Anxiety, depression, and EWB served as bridges connecting CPPS to QOL across all time points with varying degrees of importance, as did PWB at T1 and T2.
Conclusions
Treating psychological distress and enhancing EWB and PWB can be high impact intervention targets throughout the cancer trajectory.