Comparison of gastric cancer survival following R0 resection in the United States and Korea using an internationally validated nomogram

Survival Outcomes Between Minimally Invasive and Open Gastrectomy in Early and Locally Advanced Gastric Adenocarcinoma in a Western Center

PURPOSE

While minimally invasive gastrectomy (MIS) is well-utilized in Asia, its adoption in the West to treat gastric adenocarcinoma has been slower. We compare survival outcomes between open gastrectomy and MIS in a high-volume Western US center.

METHODS

In this retrospective review, demographic and clinical characteristics of gastric adenocarcinoma patients who underwent curative-intent MIS (robotic or laparoscopic approaches) or open surgery were compared via descriptive statistics. Multivariable Cox hazard regression models were constructed to assess the effects of gastrectomy type on overall survival (OS) and recurrence-free survival (RFS) in the overall cohort and a locally advanced subgroup (pathologic stage 2-3 patients).

RESULTS

A total of 135 gastric adenocarcinoma patients were studied; 67% underwent MIS. Open patients experienced lower lymph node retrieval (p = 0.004) and neoadjuvant chemotherapy administration (p = 0.037) than MIS. OS (p = 0.18) and RFS (p = 0.74) were not different between MIS and open over a 5-year period. In multivariable survival models, gastrectomy type was not associated with OS (open hazard ratio (HR) = 1.78, p = 0.8 (compared to MIS)) or RFS (HR = 1.46, p = 0.7), while positive nodes (HR = 21.7, p = 0.003) and pathologic stage 3 (HR = 1.6, p = 0.025) were associated with poorer OS. Within the locally advanced cohort (N = 66, 67% MIS), OS (p = 0.43) and RFS (p = 0.72) were similarly not different between MIS and open patients.

CONCLUSIONS

This study contributes to the growing body of evidence supporting the efficacy of MIS to manage gastric cancer within Western populations. Importantly, these data highlight the utility of MIS as a treatment option for locally advanced disease where uptake has been slowest.

Clinical predictors of postoperative complications in the context of enhanced recovery (ERAS) in patients with esophageal and gastric cancer

The overall frequency of postoperative complications in patients with esophageal and gastric cancer diverges between studies. We evaluated the frequency and assessed the relationship between complications and demographic and clinical features. For this observational study, data were extracted from the ERAS Registry managed by the University of Verona, Italy. Patients were evaluated and compared for postoperative complications according to the consensus-based classification and the Clavien-Dindo scale. The study population was 877 patients: 346 (39.5%) with esophageal and 531 (60.5%) with gastric cancer; 492 (56.2%) reported one or more postoperative complications, 213 (61.6%) of those with esophageal and 279 (52.5%) of those with gastric cancer. When stratified by consensus-based classification, patients with esophageal cancer reported general postoperative complications more frequently (p < 0.001) than those with gastric cancer, but there was no difference in postoperative surgical complications between the two groups. Multiple logistic regression models revealed an association between postoperative complications and the Charlson Comorbidity Index (adjusted odds ratio [OR] 1.22; 95% confidence interval [CI] 1.08-1.36), operation time (adjusted OR, 1.08; 95% CI 1.00-1.15), and days to solid diet intake (adjusted OR, 1.39; 95% CI 1.20-1.59). Complications in patients with esophageal and gastric cancer are frequent, even in those treated according to ERAS principles, and are often associated with comorbidities, longer operative time, and longer time to solid diet intake.

Laparoscopic Spleen-Preserving Hilar Lymphadenectomy for Advanced Proximal Gastric Cancer Without Greater Curvature Invasion: Five-Year Outcomes From the Fuges-02 Randomized Clinical Trial

Importance

Splenic hilar lymphadenectomy has been recommended for locally advanced proximal gastric cancer (APGC) involving the greater curvature. However, it is unclear whether laparoscopic spleen-preserving splenic hilar lymphadenectomy (LSPSHL) is associated with a long-term survival benefit for APGC without greater curvature invasion.

Objective

To present the 5-year follow-up data from a randomized clinical trial that compared laparoscopic total gastrectomy (D2 group) with D2 plus LSPSHL (D2 + No. 10 group) among patients with resectable APGC.

Design, Setting, and Participants

This is a post hoc secondary analysis of a randomized clinical trial that enrolled 536 patients with potentially resectable APGC (cT2-4a, N0 or N+, and M0) without greater curvature invasion from January 5, 2015, to October 10, 2018. All patients were tracked for at least 5 years. The final follow-up was on October 30, 2023.

Interventions

Patients were randomly assigned in a 1:1 ratio to the D2 + No. 10 or D2 groups.

Main Outcomes and Measures

The 5-year disease-free survival (DFS) and overall survival (OS) rates were measured. Recurrence patterns and causes of death were compared.

Results

A total of 526 patients (392 men [74.5%]; mean [SD] age, 60.6 [9.6] years) were included in the modified intent-to-treat analysis, with 263 patients in each group. The 5-year DFS rate was 63.9% (95% CI, 58.1%-69.7%) for the D2 + No. 10 group and 55.1% (95% CI, 49.1%-61.1%) for the D2 group (log-rank P = .04). A statistically significant difference was observed in the 5-year OS between the D2 + No. 10 group and the D2 group (66.2% [95% CI, 60.4%-71.9%] vs 57.4% [95% CI, 51.4%-63.4%]; log-rank P = .03). The No. 10 lymph node exhibited a therapeutic value index (TVI) of 6.5, surpassing that of Nos. 8a (TVI, 3.0), 11 (TVI, 5.8), and 12a (TVI, 0.8). A total of 86 patients in the D2 + No. 10 group (cumulative incidence, 32.7%) and 111 patients in the D2 group (cumulative incidence, 42.2%) experienced recurrence (hazard ratio, 0.72; 95% CI, 0.54-0.95; P = .02). The multivariable competing risk regression model demonstrated that D2 + No. 10 remained an independent protective factor for a lower 5-year cumulative recurrence rate after surgery (hazard ratio, 0.75; 95% CI, 0.56-1.00; P = .05). There was a significant difference in the 5-year cumulative recurrence rate at the No. 10 lymph node area between the 2 groups (D2 + No. 10 group vs D2 group: 0% vs 2.3% [n = 6]; P = .01).

Conclusions

This post hoc secondary analysis of a randomized clinical trial found that laparoscopic total gastrectomy with LSPSHL can improve the prognosis and reduce recurrence for APGC without greater curvature invasion. Future multicenter studies are warranted to validate these findings.

Trial Registration

ClinicalTrials.gov Identifier: NCT02333721.

Predicting peritoneal recurrence after radical gastrectomy for gastric cancer: Validation of a prediction model (PERI-Gastric 1 and PERI-Gastric 2) on a Korean database

BACKGROUND

Peritoneal recurrence is a significant cause of treatment failure after radical gastrectomy for gastric cancer. The prediction of metachronous peritoneal recurrence would have a significantly impact risk stratification and tailored treatment planning. This study aimed to externally validate the previously established PERI-Gastric 1 and 2 models to assess their generalizability in an independent population.

METHODS

Retrospective external validation was conducted on a cohort of 8564 patients who underwent elective gastrectomy for stage Ib-IIIc gastric cancer between 1998 and 2018 at the Yonsei Cancer Center. Discrimination was tested using the area under the receiver operating characteristic curves (AUROC). Accuracy was tested by plotting observations against the predicted risk of peritoneal recurrence and analyzing the resulting calibration plots. Clinical usefulness was tested with a decision curve analysis.

RESULTS

In the validation cohort, PERI-Gastric 1 and PERI-Gastric 2 exhibited an AUROC of 0.766 (95 % C.I. 0.752-0.778) and 0.767 (95 % C.I. 0.755-0.780), a calibration-in-the-large of 0.935 and 0.700, a calibration belt with a 95 % C.I. over the bisector in the risk range of 24%-33 % and 35%-47 %. The decision curve analysis revealed a positive net benefit in the risk range of 10%-42 % and 15%-45 %, respectively.

CONCLUSIONS

This study presents the external validation of the PERI-Gastric 1 and 2 scores in an Eastern population. The models demonstrated fair discrimination and satisfactory calibration for predicting the risk of peritoneal recurrence after radical gastrectomy, even in Eastern patients. PERI-Gastric 1 and 2 scores could also be applied to predict the risk of metachronous peritoneal recurrence in Eastern populations.

[Technique and Study Results of Laparoscopic Gastrectomy for Gastric Cancer]

The aim of this paper was to describe the technique of laparoscopic gastrectomy for gastric carcinoma and to present a review of current international studies on this topic.The first part describes and documents a standard laparoscopic gastrectomy for carcinoma. In the second part, after an EMBASE and PubMed search, a total of 123 quality-relevant randomised (RCT) and non-randomised (non-RCT) studies on laparoscopic gastrectomy are identified from a primary total of 3,042 hits by systematic narrowing. The study results are then summarised conclusively for the target criteria of feasibility, outcome, oncological quality, morbidity and mortality.Both, laparoscopic subtotal resection for distal gastric carcinomas and laparoscopic gastrectomy can now be performed safely and with few complications. In a recent literature review of a total of 15 RCTs with 5,576 patients (laparoscopic 2,793 vs. open 2,756), there were no significant differences in terms of feasibility, intraoperative outcome and oncological quality (R0 and lymph node harvest). Surgical morbidity and mortality were comparable. Patients after laparoscopic surgery showed a significantly faster early postoperative recovery with a lower overall morbidity. In contrast, the operating time was significantly longer - by a mean of 45 min - compared to the open technique. The advantages of the laparoscopic technique were equally evident in studies on early gastric carcinoma and advanced carcinomas (>T2).Laparoscopic gastrectomy for gastric carcinoma is safe to perform and shows better early postoperative recovery. Complication rates, morbidity and mortality as well as long-term oncological results are comparable with open surgery.

Nomogram for predicting overall survival after curative gastrectomy using inflammatory, nutritional and pathological factors

PURPOSE

To establish a nomogram for predicting the overall survival (OS) in patients with gastric cancer (GC) based on inflammatory, nutritional and pathological factors.

METHODS

GC patients underwent curative gastrectomy from January 2012 to June 2017 in our hospital were included, and were classified into training set and validation set with a ratio of 7:3. Then variables associated with OS were analyzed using univariate and multivariate Cox regression analysis. Nomograms predicting OS were built using variables from multivariable Cox models. Finally, Kaplan-Meier curve and Log-rank test were also conducted to analyze the 1-yr, 3-yr and 5-yr OS to validate the efficiency of risk stratification of the nomogram.

RESULTS

A total of 366 GC patients were included. After univariate and multivariate Cox regression analysis, age (HR = 1.52, 95% CI = 1.01-2.30, P = 0.044), CA50 (HR = 1.90, 95% CI = 1.12-3.21, P = 0.017), PNI (HR = 1.65, 95% CI = 1.13-2.39, P = 0.009), SII (HR = 1.46, 95% CI = 1.03-2.08, P = 0.036), T stage (HR = 2.26, 95% CI = 1.01-5.05, P = 0.048; HR = 7.24, 95% CI = 3.64-14.40, P < 0.001) were independent influencing factors on the survival time of GC patients. Five factors including CEA, prognostic nutritional index (PNI), systemic immune-inflammation index (SII), ln (tumor size), T stage, and N stage were identified and entered the nomogram, which showed good discrimination and calibration in both sets. On internal validation, 1-yr, 3-yr and 5-yr nomogram demonstrated a good discrimination with an area under the ROC curve (AUC) of 0.77, 0.84 and 0.86, respectively. The AUC for 1-yr, 3-yr and 5-yr nomogram in validation set was 0.77, 0.79 and 0.81, respectively. The OS in low risk group of training cohort and validation cohort was significantly higher than that of intermediate risk group and high risk group, respectively.

CONCLUSIONS

We established a nomogram based on PNI, SII and pathological factors for predicting OS in GC patients. In addition, its efficiency was validated by validation set and stratified analysis.

Comparison of the Prognosis of Upper-Third Gastric Cancer With That of Middle and Lower-Third Gastric Cancer

PURPOSE

Gastric cancer is one of the most common cancers in Korea, and the proportion of upper-third gastric cancers has been steadily increasing over the last two decades. This study aimed to evaluate the effect of tumor location on gastric cancer prognosis.

MATERIALS AND METHODS

We retrospectively reviewed 2,466 patients who underwent gastrectomy for pathologically proven gastric cancer between January 2011 and December 2016. The patients were divided into an upper-third group (U group; n=419, 17.0%) and a middle- and lower-third group (ML group; n=2,047, 83.0%). Clinicopathological characteristics, overall survival (OS), and recurrence-free survival (RFS) after surgery were compared.

RESULTS

The U group had more advanced disease than the ML group and a higher incidence of N3b disease for T3 (12.0% vs. 4.9%, p=0.023) and T4 tumors (33.3% vs. 17.5%, p=0.001). The 5-year RFS rate for stage III disease was marginally lower in the U group than that in the ML group (47.1% vs. 56.7%, p=0.082). The upper third location was an independent prognostic factor for both OS (hazard ratio [HR], 1.350; 95% confidence interval [CI], 1.065-1.711) and RFS (HR, 1.430; 95% CI, 1.080-1.823).

CONCLUSIONS

Upper-third gastric cancer shows extensive node metastasis compared to those located more distally in ≥T3 tumors. The upper third location is an independent prognostic factor for both OS and RFS and may have an adverse impact on RFS, particularly in patients with stage III gastric cancer.

Normalization weighted combination scores re-evaluate TNM staging of gastric cancer: a retrospective cohort study based on a multicenter database

BACKGROUND

The pathological depth of tumor invasion (pT) and lymph node metastasis (pN) are critical independent prognostic factors for patients with gastric cancer (GC), representing effective methods for evaluating prognosis. In this study, the authors employed a normalization weight combination score to calculate the weight ratio of the pT stage and pN stage. Subsequently, the authors established a novel weighted TN (wTN) staging model based on these T and N weights, evaluating its prognostic capacity.

METHODS

This study utilized a training cohort from A Medical University Cancer Hospital and a validation cohort from the SEER database. Least absolute shrinkage and selection operator (LASSO) and Cox regression were employed to screen clinical characteristics. Multivariate linear regression and cluster analysis calculated the weight ratio of T stage and N stage in the training and validation cohorts, respectively, followed by re-staging. Prognostic value was evaluated using C-index, likelihood ratio, Wald, and Score tests for wTN stage and tumor-node-metastasis (TNM) stage. A nomogram model was developed, and accuracy was assessed using receiver operating characteristic curve (ROC), decision curve analysis (DCA), and restricted cubic spline (RCS) analyses.

RESULTS

LASSO was used for initial screening, selecting eight potential features for Cox analysis. Age, tumor size, metastasis lymph nodes (MLNs), and tumor location were confirmed as independent prognostic factors. wTN was calculated in the training and validation cohorts, and nomograms were established with the independent factors. N stage had a higher weight proportion than T stage in both cohorts (0.625/0.375 in training cohort, 0.556/0.444 in validation cohort). wTN outperformed the 8th TNM stage in C-index, likelihood ratio, Wald, and Score tests in the training cohort, with successful validation in the validation cohort. Stratified analysis of distinct pathological types further demonstrates that wTN staging exhibits superior prognostic performance.

CONCLUSION

The wTN staging model based on T stage and N stage weights has a good prognostic value for GC patients. The same conclusion was obtained in different pathological stratification.

Identifying the optimal treatment strategy in patients with resectable non-cardia gastric cancer

BACKGROUND

Multimodal treatment strategy including perioperative chemotherapy (PEC), postoperative chemoradiation therapy (POCR), and postoperative chemotherapy (POC) has been accepted as the standard of care in gastric cancer (GC). The ideal sequence and type of therapy remain undetermined.

METHOD

The National Cancer Database was examined from 2006 to 2016 to identify patients with resectable non-cardia gastric cancer. Patient outcomes were compared based on the receipt of PEC, POCR, and POC. This comparison was repeated in a sub-group of patients who received optimal treatment. Optimal treatment was defined as initial chemotherapy within 45 days of diagnosis, resection within 45 days of diagnosis, negative margins, adjuvant chemotherapy within 90 days of resection and standard radiation dose (45 Gy). Kaplan-Meier test, log-rank test, and multivariable analysis (MVA) were performed.

RESULTS

We identified 9589 patients. Median survival was greater in the PEC group followed by POCR and POC (60.6, 42.3, and 31.2 months, respectively). On MVA, factors associated with worse overall survival included age above median (≥ 63 years), Charlson-Deyo score of ≥ 1, non-academic/research program, poorly differentiated/undifferentiated grade, positive margins, and positive lymph nodes. Both PEC and POCR were associated with improved survival when compared to POC (HR 0.78 and 0.79; p < 0.001). When compared with PEC, no significant difference was noted with POCR (HR 1.01; p = 0.987). These results were maintained in optimally treated cohort (n = 3418).

CONCLUSION

In patients with resectable non-cardia gastric cancer, both perioperative chemotherapy and postoperative chemoradiation therapy were associated with improved survival when compared to postoperative chemotherapy. No difference was noted between perioperative chemotherapy and postoperative chemoradiation therapy. These results were maintained in the optimally treated cohort.

Advances in RNAi therapies for gastric cancer: Targeting drug resistance and nanoscale delivery

Gastric cancer poses a significant health challenge, and exploring innovative therapeutic strategies is imperative. RNA interference (RNAi) has employed as an important therapeutic strategy for diseases by selectively targeting key pathways involved in diseases pathogenesis. Small interfering RNA (siRNA), a potent RNAi tool, possesses the capability to silence genes and downregulate their expression. This review provides a comprehensive examination of the potential applications of small interfering RNA (siRNA) and short hairpin RNA (shRNA), supplemented by an in-depth analysis of nanoscale delivery systems, in the context of gastric cancer treatment. The potential of siRNA to markedly diminish the proliferation and invasion of gastric cancer cells through the modulation of critical molecular pathways, including PI3K, Akt, and EMT, is highlighted. Besides, siRNA demonstrates its efficacy in inducing chemosensitivity in gastric tumor cells, thus impeding tumor progression. However, the translational potential of unmodified siRNA faces challenges, particularly in vivo and during clinical trials. To address this, we underscore the pivotal role of nanostructures in facilitating the delivery of siRNA to gastric cancer cells, effectively suppressing their progression and enhancing gene silencing efficiency. These siRNA-loaded nanoparticles exhibit robust internalization into gastric cancer cells, showcasing their potential to significantly reduce tumor progression. The translation of these findings into clinical trials holds promise for advancing the treatment of gastric cancer patients.

Predicting residual neoplasia after a non-curative gastric ESD: validation and modification of the eCura system in the Western setting: the W-eCura score

OBJECTIVE

To evaluate the risk factors for lymph node metastasis (LNM) after a non-curative (NC) gastric endoscopic submucosal dissection (ESD) and to validate and eventually refine the eCura scoring system in the Western setting. Also, to assess the rate and risk factors for parietal residual disease.

DESIGN

Retrospective multicentre multinational study of prospectively collected registries from 19 Western centres. Patients who had been submitted to surgery or had at least one follow-up endoscopy were included. The eCura system was applied to assess its accuracy in the Western setting, and a modified version was created according to the results (W-eCura score). The discriminative capacities of the eCura and W-eCura scores to predict LNM were assessed and compared.

RESULTS

A total of 314 NC gastric ESDs were analysed (72% high-risk resection (HRR); 28% local-risk resection). Among HRR patients submitted to surgery, 25% had parietal disease and 15% had LNM in the surgical specimen. The risk of LNM was significantly different across the eCura groups (areas under the receiver operating characteristic curve (AUC-ROC) of 0.900 (95% CI 0.852 to 0.949)). The AUC-ROC of the W-eCura for LNM (0.916, 95% CI 0.870 to 0.961; p=0.012) was significantly higher compared with the original eCura. Positive vertical margin, lymphatic invasion and younger age were associated with a higher risk of parietal residual lesion in the surgical specimen.

CONCLUSION

The eCura scoring system may be applied in Western countries to stratify the risk of LNM after a gastric HRR. A new score is proposed that may further decrease the number of unnecessary surgeries.

Risk of venous thromboembolism in patients undergoing gastric cancer surgery: a systematic review and meta-analysis

BACKGROUND

Venous thromboembolism (VTE) is a common postoperative complication in patients undergoing surgery for gastric cancer (GC). Although VTE incidence may vary among cancers, guidelines rarely stratify preventive methods for postoperative VTE by cancer type. The risk of VTE in patients undergoing surgery for GC remains unclear.

METHODS

A systematic review and meta-analysis was undertaken to determine the risk of VTE after GC surgery and discuss the clinical value of pharmacological thromboprophylaxis in these cases. Medline, Embase, Web of Science, and Cochrane Library databases were searched for articles published from their inception to September 2022.

RESULTS

Overall, 13 studies (111,936 patients) were included. The overall 1-month incidence of VTE, deep vein thrombosis (DVT), and pulmonary embolism (PE) after GC surgery was 1.8% (95% CI, 0.8-3.1%; I²=98.5%), 1.2% (95% CI, 0.5-2.1%; I²=96.1%), and 0.4% (95% CI, 0.1-1.1%; I²=96.3%), respectively. The prevalence of postoperative VTE was comparable between Asian and Western populations (1.8% vs. 1.8%; P > 0.05). Compared with mechanical prophylaxis alone, mechanical plus pharmacological prophylaxis was associated with a significantly lower 1-month rate of postoperative VTE and DVT (0.6% vs. 2.9% and 0.6% vs. 2.8%, respectively; all P < 0.05), but not PE (P > 0.05). The 1-month postoperative incidence of VTE was not significantly different between laparoscopic and open surgery (1.8% vs. 4.3%, P > 0.05).

CONCLUSION

Patients undergoing GC surgery do not have a high risk of VTE. The incidence of VTE after GC surgery is not significantly different between Eastern and Western patients. Mechanical plus pharmacological prophylaxis is more effective than mechanical prophylaxis alone in postoperative VTE prevention. The VTE risk is comparable between open and laparoscopic surgery for GC.

Contemporary Cancer Program Practice Profile Report Compliance Rates for Gastric Cancer: A National Cancer Database Analysis

BACKGROUND

The Commission on Cancer (CoC) established quality measures to be reported in National Cancer Database (NCDB) Quality Reporting Tools. Compliance is provided to accredited cancer programs as Cancer Program Practice Profile Reports (CP3R). At the time of this study, the quality metric for gastric cancer (GC) was removal and pathologic examination of 15 regional lymph nodes for resected GC (G15RLN).

OBJECTIVE

This study evaluates national trends in quality metric compliance for GC based on CoC CP3R.

METHODS

The National Cancer Database (NCDB) was queried from 2004-2017 to identify patients with stage I-III GC who met criteria for inclusion. National trends in compliance were compared. Overall survival (OS) was compared stage for stage.

RESULTS

Overall, 42 997 patients with GC qualified. In 2017, 64.5% of patients met compliance with G15RLN compared to 31.4% in 2004. When comparing academic and non-academic institutions, compliance was met 67.0% vs 60.0% of the time in 2017 (P < .01) and 36% vs 30.6% of the time in 2004 (P < .01). On multivariate logistic regression, patients receiving care at academic institutions (OR 1.5, 95% CI 1.4-1.5) and who underwent surgery at institutions in the >75th percentile for case volume (OR 1.5, 95% CI 1.4-1.6) had higher odds of compliance. When stratified by stage, median OS was better across all stages when compliance was met.

CONCLUSION

Compliance rates with GC quality measures have improved over time. Compliance with the G15RLN metric is associated with improved OS, stage for stage. Continued efforts to improve compliance rates across all institutions are critical.

Application of the Khorana score for cancer-associated thrombosis prediction in patients of East Asian ethnicity undergoing ambulatory chemotherapy

BACKGROUND

The Khorana score (KS) has not been well studied in East Asian cancer patients, who have different genetic backgrounds for inherited thrombophilia, body metabolism, and cancer epidemiology.

METHODS

By using the Common Data Model, we retrospectively collected deidentified data from 11,714 consecutive newly diagnosed cancer patients who underwent first-line chemotherapy from December 2015 to December 2021 at a single institution in Korea, and we applied the KS for cancer-associated thrombosis (CAT) prediction. Age at diagnosis, sex, and use of highly thrombogenic chemotherapeutics were additionally investigated as potential risk factors for CAT development.

RESULTS

By 6 months after chemotherapy initiation, 207 patients (1.77%) experienced CAT. Only 0.4% had a body mass index (BMI) ≥ 35 kg/m² and changing the cutoff to 25 kg/m² improved the prediction of CAT. Age ≥ 65 years and the use of highly thrombogenic chemotherapeutics were independently associated with CAT development. KS values of 1 ~ 2 and ≥ 3 accounted for 52.3% and 7.6% of all patients, respectively, and the incidence of CAT in these groups was 2.16% and 4.16%, respectively, suggesting a lower incidence of CAT in the study population than in Westerners. The KS component regarding the site of cancer showed a good association with CAT development but needed some improvement.

CONCLUSION

The KS was partially validated to predict CAT in Korean cancer patients undergoing modern chemotherapy. Modifying the BMI cutoff, adding other risk variables, and refining the use of cancer-site data for CAT risk prediction may improve the performance of the KS for CAT prediction in East Asian patients.

Updates on global epidemiology, risk and prognostic factors of gastric cancer

Gastric cancer (GC) is defined as the primary epithelial malignancy derived from the stomach, and it is a complicated and heterogeneous disease with multiple risk factors. Despite its overall declining trend of incidence and mortality in various countries over the past few decades, GC remains the fifth most common malignancy and the fourth leading cause of cancer-related death globally. Although the global burden of GC has shown a significant downward trend, it remains severe in certain areas, such as Asia. GC ranks third in incidence and mortality among all cancer types in China, and it accounts for nearly 44.0% and 48.6% of new GC cases and GC-related deaths in the world, respectively. The regional differences in GC incidence and mortality are obvious, and annual new cases and deaths are increasing rapidly in some developing regions. Therefore, early preventive and screening strategies for GC are urgently needed. The clinical efficacies of conventional treatments for GC are limited, and the developing understanding of GC pathogenesis has increased the demand for new therapeutic regimens, including immune checkpoint inhibitors, cell immunotherapy and cancer vaccines. The present review describes the epidemiology of GC worldwide, especially in China, summarizes its risk and prognostic factors, and focuses on novel immunotherapies to develop therapeutic strategies for the management of GC patients.

Reliability of the Lymph Node Ratio in the Prediction of Gastric Cancer Survival

Background. Lymph node metastasis is the major determinant factor in the prognosis of gastric cancer. There is still no definite consensus on the lymph node number that should be harvested during gastric cancer surgery. Lymph Node Ratio (LNR) is defined as the ratio of metastatic nodes to the total number of pathologically examined lymph nodes. LNR has been proposed to be a sensitive prognostic factor in patients with gastric cancer. In this study the reliability of the LNR is tested for being a prognostic factor in gastric cancer survival. Methods. Medical records of 244 patients, with neither distant metastases nor neoadjuvant treatment underwent curative gastrectomy, were analyzed retrospectively in terms of survival according to the lymph node ratio (LNR). Patients were divided in two groups by using LNR cut-off value. Results. LNR of 0.4 was proved to be the best cut-off value to predict the prognosis of patients with gastric cancer. Univariate and multivariate analysis revealed that age over 65 (p < 0.001), and LNR ≥ 0.4 (p = 0.02) were independent factors in gastric cancer survival. Patients with LNR ≥ 0.4 presented with worse outcomes regarding other prognostic parameters (tumor differentiation, tumor diameter, lymphovascular invasion or perineural invasion), despite similar numbers of lymph nodes being harvested in both groups during surgery. Conclusion. Lymph node ratio is a reliable parameter to predict the survival in gastric cancer.

A Comprehensive Review of Prognostic Factors in Patients with Gastric Adenocarcinoma

Gastric adenocarcinoma remains associated with a poor long-term survival, despite recent therapeutical advances. In most parts of the world where systematic screening programs do not exist, diagnosis is often made at advanced stages, affecting long-term prognosis. In recent years, there is increasing evidence that a large bundle of factors, ranging from the tumor microenvironment to patient ethnicity and variations in therapeutic strategy, play an important role in patient outcome. A more thorough understanding of these multi-faceted parameters is needed in order to provide a better assessment of long-term prognosis in these patients, which probably also require the refinement of current staging systems. This study aims to review existing knowledge on the clinical, biomolecular and treatment-related parameters that have some prognostic value in patients with gastric adenocarcinoma.

Survival benefit of younger gastric cancer patients in China and the United States: A comparative study

BACKGROUND

The impact of racial and regional disparity on younger patients with gastric cancer (GC) remains unclear.

AIM

To investigate the clinicopathological characteristics, prognostic nomogram, and biological analysis of younger GC patients in China and the United States.

METHODS

From 2000 to 2018, GC patients aged less than 40 years were enrolled from the China National Cancer Center and the Surveillance Epidemiology and End Results database. Biological analysis was performed based on the Gene Expression Omnibus database. Survival analysis was conducted via Kaplan-Meier estimates and Cox proportional hazards models.

RESULTS

A total of 6098 younger GC patients were selected from 2000 to 2018, of which 1159 were enrolled in the China National Cancer Center, and 4939 were collected from the Surveillance Epidemiology and End Results database. Compared with the United States group, younger patients in China revealed better survival outcomes (P < 0.01). For race/ethnicity, younger Chinese cases also enjoyed a better prognosis than that in White and Black datasets (P < 0.01). After stratification by pathological Tumor-Node-Metastasis (pTNM) stage, a survival advantage was observed in China with pathological stage I, III, and IV (all P < 0.01), whereas younger GC patients with stage II showed no difference (P = 0.16). In multivariate analysis, predictors in China involved period of diagnosis, linitis plastica, and pTNM stage, while race, diagnostic period, sex, location, differentiation, linitis plastica, signet ring cell, pTNM stage, surgery, and chemotherapy were confirmed in the United States group. Prognostic nomograms for younger patients were established, with the area under the curve of 0.786 in the China group and of 0.842 in the United States group. Moreover, three gene expression profiles (GSE27342, GSE51105, and GSE38749) were enrolled in further biological analysis, and distinctive molecular characteristics were identified in younger GC patients among different regions.

CONCLUSION

Except for younger cases with pTNM stage II, a survival advantage was observed in the China group with pathological stage I, III, and IV compared to the United States group, which might be partly due to differences in surgical approaches and the improvement of the cancer screening in China. The nomogram model provided an insightful and applicable tool to evaluate the prognosis of younger patients in China and the United States. Furthermore, biological analysis of younger patients was performed among different regions, which might partly explain the histopathological behavior and survival disparity in the subpopulations.

Risk of Lymph Node Metastasis in T1b Gastric Cancer: An International Comprehensive Analysis from the Global Gastric Group (G3) Alliance

OBJECTIVE

We sought to define criteria associated with low lymph node metastasis risk in patients with submucosal (pT1b) gastric cancer from 3 Western and 3 Eastern countries.

SUMMARY BACKGROUND DATA

Accurate prediction of lymph node metastasis risk is essential when determining the need for gastrectomy with lymph node dissection following endoscopic resection. Under present guidelines, endoscopic resection is considered definitive treatment if submucosal invasion is only superficial, but this is not routinely assessed.

METHODS

Lymph node metastasis rates were determined for patient groups defined according to tumor pathological characteristics. Clinicopathological predictors of lymph node metastasis were determined by multivariable logistic regression and used to develop a nomogram in a randomly selected subset that was validated in the remainder. Overall survival was compared between Eastern and Western countries.

RESULTS

Lymph node metastasis was found in 701 of 3166 (22.1%) Eastern and 153 of 560 (27.3%) Western patients. Independent predictors of lymph node metastasis were female sex, tumor size, distal stomach location, lymphovascular invasion, and moderate or poor differentiation. Patients fulfilling the National Comprehensive Cancer Network guideline criteria, excluding the requirement that invasion not extend beyond the superficial submucosa, had a lymph node metastasis rate of 8.9% (53/594). Excluding moderately differentiated tumors lowered the rate to 3.4% (10/296). The nomogram's area under the curve was 0.690. Regardless of lymph node status, overall survival was better in Eastern patients.

CONCLUSIONS

The lymph node metastasis rate was lowest in patients with well differentiated tumors that were ≤3 cm and lacked lymphovascular invasion. These criteria may be useful in decisions regarding endoscopic resection as definitive treatment for pT1b gastric cancer.

Clinical outcomes of patients with complicated post-operative course after gastrectomy for cancer: a GIRCG study using the GASTRODATA registry

Gastrectomy for gastric cancer is still performed in Western countries with high morbidity and mortality. Post-operative complications are frequent, and effective diagnosis and treatment of complications is crucial to lower the mortality rates. In 2015, a project was launched by the EGCA with the aim of building an agreement on list and definitions of post-operative complications specific for gastrectomy. In 2018, the platform www.gastrodata.org was launched for collecting cases by utilizing this new complication list. In the present paper, the Italian Research Group for Gastric Cancer endorsed a collection of complicated cases in the period 2015-2019, with the aim of investigating the clinical pictures, diagnostic modalities, and treatment approaches, as well as outcome measures of patients experiencing almost one post-operative complication. Fifteen centers across Italy provided 386 cases with a total of 538 complications (mean 1.4 complication/patient). The most frequent complications were non-surgical infections (gastrointestinal, pulmonary, and urinary) and anastomotic leaks, accounting for 29.2% and 17.3% of complicated patients, with a median Clavien-Dindo score of II and IIIB, respectively. Overall mortality of this series was 12.4%, while mortality of patients with anastomotic leak was 25.4%. The clinical presentation with systemic septic signs, the timing of diagnosis, and the hospital volume were the most relevant factors influencing outcome.

Assessment of Laparoscopic Spleen-Preserving Hilar Lymphadenectomy for Advanced Proximal Gastric Cancer Without Invasion Into the Greater Curvature: A Randomized Clinical Trial

Importance

The survival benefit of laparoscopic total gastrectomy combined with spleen-preserving splenic hilar lymphadenectomy (LSTG) for locally advanced proximal gastric cancer (APGC) without invasion into the greater curvature remains uncertain.

Objective

To compare the long-term and short-term efficacy of LSTG (D2 + No. 10 group) and conventional laparoscopic total gastrectomy (D2 group) for patients with APGC that has not invaded the greater curvature.

Design, Setting, and Participants

In this open-label, prospective randomized clinical trial, a total of 536 patients with clinical stage cT2 to 4a/N0 to 3/M0 APGC without invasion into the greater curvature were enrolled from January 2015 to October 2018. The final follow-up was on October 31, 2021. Data were analyzed from December 2021 to February 2022.

Interventions

Eligible patients were randomized to the D2 + No. 10 group or the D2 group.

Main Outcomes and Measures

The primary outcome was 3-year disease-free survival (DFS). The secondary outcomes were 3-year overall survival (OS) and morbidity and mortality within 30 days after surgery.

Results

Of 526 included patients, 392 (74.5%) were men, and the mean (SD) age was 60.6 (9.6) years. A total of 263 patients were included in the D2 + No. 10 group, and 263 were included in the D2 group. The 3-year DFS was 70.3% (95% CI, 64.8-75.8) for the D2 + No. 10 group and 64.3% (95% CI, 58.4-70.2; P = .11) for the D2 group, and the 3-year OS in the D2 + No. 10 group was better than that in the D2 group (75.7% [95% CI, 70.6-80.8] vs 66.5% [95% CI, 60.8-72.2]; P = .02). Multivariate analysis revealed that splenic hilar lymphadenectomy was not an independent protective factor for DFS (hazard ratio [HR], 0.86; 95% CI, 0.63-1.16) or OS (HR, 0.81; 95% CI, 0.59-1.12). Stratification analysis showed that patients with advanced posterior gastric cancer in the D2 + No. 10 group had better 3-year DFS (92.9% vs 39.3%; P < .001) and OS (92.9% vs 42.9%; P < .001) than those in the D2 group. Multivariate analysis confirmed that patients with advanced posterior gastric cancer could have the survival benefit from No. 10 lymph node dissection (DFS: HR, 0.10; 95% CI, 0.02-0.46; OS: HR, 0.12; 95% CI, 0.03-0.52).

Conclusions and Relevance

Although LSTG could not significantly improve the 3-year DFS of patients with APGC without invasion into the greater curvature, patients with APGC located posterior gastric wall may benefit from LSTG.

Trial Registration

ClinicalTrials.gov Identifier: NCT02333721.

Survival in stomach cancer: analysis of a national cancer information system and a population-based cancer registry in Colombia

Background

Stomach cancer is among the most frequent, is a leading cause of mortality in low- and middle-income countries. Assessing its survival is important to guide evidence-based health policies.

Aims

To estimate stomach cancer survival in Colombia (2014-2019) with data from the National Cancer Information System (NCIS) and in Cali with data from the Cali Population Cancer Registry (RPCC) (1998-2017).

Methods

NCIS estimated the overall 3-year net survival for 8,549 people, while RPCC estimated 5-year net survival for 6,776 people.

Results

The 3-year net survival was 36.8% (95% CI: 35.5-38.1). Net survival was higher in people with special insurance (61.7%; 95% CI: 44.8-74.8) or third payer (40.5%; 95% CI: 38.7-42.3) than state insurance (30.7%; 95% CI: 28.7-32.8). It was also higher in women and people diagnosed at early stages. Multivariable analysis showed consistency with survival estimations with a higher risk of death in men, people with state insurance, and diagnosed at advanced stages. In Cali, the 5-year net survival remained stable in men during the last 20 years. In women the 5-year net survival in women increased 8.60 percentage points, equivalent to a 50% increase compared to the 1998-2002 period. For 2013-17, it was 19.1% (95%CI: 16.2-22.2) in men, and 24.8% (95% CI: 20.4-29.3) in women.

Conclusions

Population survival estimates from the RPCC were lower than those observed in the NCIS. The differences in their methods and scope can explain variability. Nevertheless, our findings could be complementary to improve cancer control planning in the country.

Multi‑institutional development and validation of a nomogram to predict prognosis of early-onset gastric cancer patients

Background

Early-onset gastric cancer (EOGC, ≤45 years old) is characterized with increasing incidence and more malignant phenotypes compared with late-onset gastric cancer, which exhibits remarkable immune cell infiltration and is potential immunotherapeutic population. Till now, restricted survival information of EOGC is available due to limited case numbers. This study established a novel nomogram to help evaluate cancer-specific survival (CSS) of EOGC patients who underwent gastrectomy, and may provide evidence for predicting patients’ survival.

Methods

We retrospectively enrolled a cohort containing 555 EOGC cases from five independent medical centers in China, among which 388 cases were randomly selected into a training set while the other 167 cases were assigned into the internal validation set. Asian or Pacific Islander (API) patients diagnosed with EOGC during 1975-2016 were retrieved from the SEER database (n=299) and utilized as the external validation cohort. Univariate and multivariate analyses were conducted to test prognostic significances of clinicopathological factors in the training set. Accordingly, two survival nomogram models were established and compared by concordance index (C-index), calibration curve, receiver operating characteristics (ROC) curves and decision curve analyses (DCA).

Results

The 5-year CSS rate of training cohort was 61.3% with a median survival time as 97.2 months. High consistency was observed on calibration curves in all three cohorts. Preferred nomogram was selected due to its better performance on ROC and DCA results. Accordingly, a novel predicative risk model was introduced to better stratify high-risk EOGC patients with low-risk patients. In brief, the 5-year CSS rates for low-risk groups were 92.9% in training set, 83.1% in internal validation set, 89.9% in combined NQSQS cohort, and 85.3% in SEER-API cohort. In contrast, the 5-year CSS rates decreased to 38.5%, 44.3%, 40.5%, and 36.9% in the high-risk groups of the four cohorts above, respectively. The significant survival difference between high-risk group (HRG) and low-risk group (LRG) indicated the precise accuracy of our risk model. Furthermore, the risk model was validated in patients with different TNM stages, respectively. Finally, an EOGC web-based survival calculator was established with public access, which can help predict prognosis.

Conclusions

Our data provided a precise nomogram on predicting CSS of EOGC patients with potential clinical applicability.

A nomogram to predict survival probability of gastric cancer patients undergoing radical surgery and adjuvant chemotherapy

Gastric cancer (GC) is the third-leading cause of cancer mortality worldwide. The aim of this study was to develop a nomogram that estimates 1-year, 3-year, and 5-year survival probability of GC patients after D2 gastrectomy combined with adjuvant chemotherapy. The results showed that median age is 58 (range: 18-85) years in the training cohort and 59 (range: 32-85) years in the validation cohort. On multivariate analysis, four factors were found to be significantly associated with worse overall survival (OS): late TNM stage, positive resection margin, preoperative carcinoembryonic antigen (CEA) level, and single chemotherapy regimens compared with multiple chemotherapy regimens. All of these findings were validated in the validation cohort. Furthermore, the four factors were included in the final nomogram for the prediction of 1-year, 3-year, and 5-year survival probability, with accurate calibration and reasonable discrimination (C-index = 0.676 for training cohort, and C-index = 0.664 for validation cohort). The AUC values analyzed by the ROC analysis demonstrated a good predictive accuracy of the nomogram for OS (1-year, 3-year, and 5-year OS were 94.43%, 77.42%, and 73.03% in the training cohort, respectively; 96.95%, 81.54%, and 73.41% in the validation cohort, respectively). In conclusion, the proposed nomogram may be used to objectively and accurately predict survival probability of GC patients in a multi-institutional clinical setting.

Prognostic and Predictive Model of the Log Odds of the Negative Lymph Node/T Stage Ratio in Resectable Gastric Adenocarcinoma Patients

PURPOSE

There are few reports on disease-specific survival (DSS) prediction systems for resected gastric cancer (GC) patients. The aim of this study was to create a nomogram based on the log odds of the negative lymph node/T stage ratio (LONT) for individual risk prediction.

METHODS

We applied the Surveillance, Epidemiology, and End Results (SEER) Program database released in 2021 to screen GC patients from 2010 to 2015. Using a competitive risk model, we plotted the cumulative risk curve of variables for gastric cancer-specific death and death from other causes at each time point. According to the minimum BIC, we constructed and assessed a nomogram for the 12-month, 36-month, and 60-month cumulative mortality probabilities assessed by time-dependent ROC curves (time-AUCs), the C-index, Brier scores, decision curve analysis (DCA), and calibration curves.

RESULTS

A total of 3895 patients were ultimately included and randomly assigned to two sets: the training set (n = 2726, 70%) and the validation set (n = 1169, 30%). The LONT was a remarkable independent predictor of gastric cancer-specific death (high versus low: 0.705, 95% CI 0.524-0.95, p = 0.021). The variables selected based on the minimum BIC were as follows: location, AJCC, AJCC.T, AJCC.N, radiotherapy, LONT.cat, and chemotherapy. According to the time-AUC, C-index, Brier score, DCA, and calibration curves, the nomogram risk score had excellent survival prediction ability for DSS.

CONCLUSIONS

A low LONT was associated with a high cumulative incidence of DSS. A prognostic nomogram model based on the LONT could effectively predict DSS for resectable GC patients.

Randomized, Double-Blind, Placebo-Controlled Phase III Study of Paclitaxel ± Napabucasin in Pretreated Advanced Gastric or Gastroesophageal Junction Adenocarcinoma

PURPOSE

To compare napabucasin (generator of reactive oxygen species) plus paclitaxel with paclitaxel only in patients with second-line advanced gastric or gastroesophageal junction (GEJ) adenocarcinoma.

EXPERIMENTAL DESIGN

In the double-blind, phase III BRIGHTER study (NCT02178956), patients were randomized (1:1) to napabucasin (480 mg orally twice daily) plus paclitaxel (80 mg/m2 i.v. weekly for 3 of 4 weeks) or placebo plus paclitaxel. The primary endpoint was overall survival (OS). Secondary endpoints included progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and safety.

RESULTS

Overall, 714 patients were randomized (napabucasin plus paclitaxel, n = 357; placebo plus paclitaxel, n = 357). 72.1% were male, 74.6% had gastric adenocarcinoma, and 46.2% had peritoneal metastases. The study was unblinded following an interim analysis at 380 deaths. The final efficacy analysis was performed on 565 deaths (median follow-up, 6.8 months). No significant differences were observed between napabucasin plus paclitaxel and placebo plus paclitaxel for OS (6.93 vs. 7.36 months), PFS (3.55 vs. 3.68 months), ORR (16% vs. 18%), or DCR (55% vs. 58%). Grade ≥3 adverse events occurred in 69.5% and 59.7% of patients administered napabucasin plus paclitaxel and placebo plus paclitaxel, respectively, with grade ≥3 diarrhea reported in 16.2% and 1.4%, respectively.

CONCLUSIONS

Adding napabucasin to paclitaxel did not improve survival in patients with pretreated advanced gastric or GEJ adenocarcinoma. Consistent with previous reports, the safety profile of napabucasin was driven by manageable gastrointestinal events; grade ≥3 diarrhea occurred at a higher frequency with napabucasin plus paclitaxel versus placebo plus paclitaxel.

Targeting MET amplification in Gastro-oesophageal (GO) malignancies and overcoming MET inhibitor resistance: challenges and opportunities

INTRODUCTION

MET, the hepatocyte growth factor receptor is amplified in 8% of gastroesophageal (GO) malignancies and associated with poor prognosis. Therapeutic targeting of MET amplification and MET mutations has the potential to improve outcomes for patients with GO cancers (GOC).

AREAS COVERED

The efficacy of MET inhibition (METi) in preclinical studies has yet to translate into meaningful improvements in the treatment paradigm for unselected GOC. MET amplification has been proposed as a superior modality for patient selection; however even if confirmed, frequency and duration of response to METi are limited by rapid activation of primary and secondary resistance pathways. These observations illustrate the challenges inherent in the application of precision oncology predicated on the theory of oncogenic addiction.

EXPERT OPINION

A standardized definition of MET positivity is critical to enhance patient selection. Early successes targeting the METex14 skipping mutation demonstrate the potent therapeutic effects of METi in a clearly molecularly defined cohort. There is robust preclinical rationale and early-phase data supporting exploitation of immune system interaction with MET. Pragmatic investigation of rational therapeutic combinations based on molecular profiling of both primary and metastatic disease sites with sequential circulating tumor DNA analysis can inform successful clinical development of METi agents in GOC.

Comparison between laparoscopic uncut Roux-en-Y and Billroth II with Braun anastomosis after distal gastrectomy: A meta-analysis

BACKGROUND

Conventional Billroth II (BII) anastomosis after laparoscopic distal gastrectomy (LDG) for gastric cancer (GC) is associated with bile reflux gastritis, and Roux-en-Y anastomosis is associated with Roux-Y stasis syndrome (RSS). The uncut Roux-en-Y (URY) gastrojejunostomy reduces these complications by blocking the entry of bile and pancreatic juice into the residual stomach and preserving the impulse originating from the duodenum, while BII with Braun (BB) anastomosis reduces the postoperative biliary reflux without RSS. Therefore, the purpose of this study was to compare the efficacy and safety of laparoscopic URY with BB anastomosis in patients with GC who underwent radical distal gastrectomy.

AIM

To evaluate the value of URY in patients with GC.

METHODS

PubMed, Embase, Web of Science, Cochrane Library, Chinese National Knowledge Infrastructure, Wanfang, Chinese Biomedical Database, and VIP Database for Chinese Technical Periodicals (VIP) were used to search relevant studies published from January 1994 to August 18, 2021. The following databases were also used in our search: Clinicaltrials.gov, Data Archiving and Networked Services, the World Health Organization International Clinical Trials Registry Platform Search Portal (https://www.who.int/clinical-trials-registry-platform/the-ictrp-search-portal), the reference lists of articles and relevant conference proceedings in August 2021. In addition, we conducted a relevant search by Reference Citation Analysis (RCA) (https://www.referencecitationanalysis.com). We cited high-quality references using its results analysis functionality. The methodological quality of the eligible randomized clinical trials (RCTs) was evaluated using the Cochrane Risk of Bias Tool, and the non-RCTs were evaluated using the Newcastle-Ottawa scale. Statistical analyses were performed using Review Manager (Version 5.4).

RESULTS

Eight studies involving 704 patients were included in this meta-analysis. The incidence of reflux gastritis [odds ratio = 0.07, 95% confidence interval (CI): 0.03-0.19, P < 0.00001] was significantly lower in the URY group than in the BB group. The pH of the postoperative gastric fluid was lower in the URY group than in the BB group at 1 d [mean difference (MD) = -2.03, 95%CI: (-2.73)-(-1.32), P < 0.00001] and 3 d [MD = -2.03, 95%CI: (-2.57)-(-2.03), P < 0.00001] after the operation. However, no significant difference in all the intraoperative outcomes was found between the two groups.

CONCLUSION

This work suggests that URY is superior to BB in gastrointestinal reconstruction after LDG when considering postoperative outcomes.

PD-L1 expression and overall survival in Asian and western patients with gastric cancer

Aim: Data are limited on PD-L1 expression and its association with overall survival (OS) in gastric cancer (GC) patients receiving routine care in different regions. Materials & methods: In a retrospective study, PD-L1 expression was assayed using the 22C3 pharmDx on GC tumor samples collected between 2003 and 2017 at South Korean and US cancer centers. PD-L1 positivity was defined as combined positive score (CPS) ≥1. The relationship between PD-L1 and OS was analyzed. Results: Of 574 GC tumor samples, 67.4% were CPS ≥1 (68.7% in Korean and 65.7% in US patients). PD-L1 expression was not associated with OS (adjusted hazard ratio: 0.94; 95% CI: 0.75-1.17). Conclusion: PD-L1 prevalence and its association with OS was similar between South Korean and US GC patients.

Open and minimally invasive gastrectomy in Eastern and Western patient populations: A review of the literature and reasons for differences in outcomes

Randomized trials in the East have established minimally invasive gastrectomy as possibly superior for short-term outcomes and noninferior for long-term survival. Smaller randomized studies from Western countries have supported these findings. However, there are marked disparities in morbidity, mortality, and overall survival noted between Eastern and Western studies. In this article, we review the literature comparing open and minimally invasive gastrectomy in the East and West, and describe the possible reasons for differences in outcomes.

Immunotherapy in Gastro-Oesophageal Cancer: Current Practice and the Future of Personalised Therapy

Initial studies of immune checkpoint inhibitors in biomarker unselected gastro-oesophageal cancer yielded limited improvement in survival. However, emerging data from recent clinical trials suggest immunotherapies may offer a meaningful clinical benefit within selected populations. Gastro-oesophageal cancer is a heterogeneous disease with respect to histopathological and molecular features; hypermutation and the biology of immune checkpoint pathways are key to appropriate selection of populations most likely to benefit from immune checkpoint inhibitors. Programmed death-ligand 1 expression, typically measured using the combined positive score, is an important biomarker in determining which patients may benefit from immunotherapy agents. However, combined positive score thresholds are not standardised across trials and the benefit in programmed death-ligand 1-negative cohorts is uncertain. Data suggest that patients with tumours with microsatellite instability, high tumour mutational burden and Epstein-Barr Virus positivity are more likely to benefit from immunotherapy, which may be of importance within programmed death-ligand 1-negative populations. Here, we describe the current evidence base for the use of checkpoint inhibitors in the treatment of advanced gastro-oesophageal cancer and adjuvant treatment of high-risk oesophageal cancer, as well as the ongoing studies of immunotherapy in the treatment of patients with gastro-oesophageal cancers across an increasing range of clinical settings.

Laparoscopic vs. Open Gastrectomy for Locally Advanced Gastric Cancer: A Propensity Score-Matched Retrospective Case-Control Study

Introduction: Minimally invasive surgery has been increasingly used in the treatment of gastric cancer. While laparoscopic gastrectomy has become standard therapy for early-stage gastric cancer, especially in Asian countries, the use of minimally invasive techniques has not attained the same widespread acceptance for the treatment of more advanced tumours, principally due to existing concerns about its feasibility and oncological adequacy. We aimed to examine the safety and oncological effectiveness of laparoscopic technique with radical intent for the treatment of patients with locally advanced gastric cancer by comparing short-term surgical and oncologic outcomes of laparoscopic versus open gastrectomy with D2 lymphadenectomy at two Western regional institutions. Methods: The trial was designed as a retrospective comparative matched case-control study for postoperative pathological diagnoses of locally advanced gastric carcinoma. Between January 2015 and September 2021, 120 consecutive patients who underwent curative-intent laparoscopic gastrectomy with D2 lymph node dissection were retrospectively recruited and compared with 120 patients who received open gastrectomy. In order to obtain a comparison that was as homogeneous as possible, the equal control group of pairing (1:1) patients submitted to open gastrectomy who matched those of the laparoscopic group was statistically generated by using a propensity matched score method. The following potential confounder factors were aligned: age, gender, Body Mass Index (BMI), comorbidity, ASA, adjuvant therapy, tumour location, type of gastrectomy, and pT stage. Patient demographics, operative findings, pathologic characteristics, and short-term outcomes were analyzed. Results: In the case-control study, the two groups were clearly comparable with respect to matched variables, as was expected given the intentional primary selective criteria. No statistically significant differences were revealed in overall complications (16.7% vs. 20.8%, p = 0.489), rate of reoperation (3.3% vs. 2.5%, p = 0.714), and mortality (4.2% vs. 3.3%, p = 0.987) within 30 days. Pulmonary infection and wound complications were observed more frequently in the OG group (0.8% vs. 4.2%, p < 0.01, for each of these two categories). Anastomotic and duodenal stump leakage occurred in 5.8% of the patients after laparoscopic gastrectomy and in 3.3% after open procedure (p = 0.072). The laparoscopic approach was associated with a significantly longer operative time (212 vs. 192 min, p < 0.05) but shorter postoperative length of stay (9.1 vs. 11.6 days, p < 0.001). The mean number of resected lymph nodes after D2 dissection (31.4 vs. 33.3, p = 0.134) and clearance of surgical margins (97.5% vs. 95.8%, p = 0.432) were equivalent between the groups. Conclusion: Laparoscopic gastrectomy with D2 nodal dissection appears to be safe and feasible in terms of perioperative morbidity for locally advanced gastric cancer, with comparable oncological equivalency with respect to traditional open surgery.

Lenvatinib inhibits the growth of gastric cancer patient-derived xenografts generated from a heterogeneous population

BACKGROUND

Lenvatinib is a multitargeted tyrosine kinase inhibitor that is being tested in combination with immune checkpoint inhibitors to treat advanced gastric cancer; however, little data exists regarding the efficacy of lenvatinib monotherapy. Patient-derived xenografts (PDX) are established by engrafting human tumors into immunodeficient mice. The generation of PDXs may be hampered by growth of lymphomas. In this study, we compared the use of mice with different degrees of immunodeficiency to establish PDXs from a diverse cohort of Western gastric cancer patients. We then tested the efficacy of lenvatinib in this system.

METHODS

PDXs were established by implanting gastric cancer tissue into NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG) or Foxn1nu (nude) mice. Tumors from multiple passages from each PDX line were compared histologically and transcriptomically. PDX-bearing mice were randomized to receive the drug delivery vehicle or lenvatinib. After 21 days, the percent tumor volume change (%Δvtumor) was calculated.

RESULTS

23 PDX models were established from Black, non-Hispanic White, Hispanic, and Asian gastric cancer patients. The engraftment rate was 17% (23/139). Tumors implanted into NSG (16%; 18/115) and nude (21%; 5/24) mice had a similar engraftment rate. The rate of lymphoma formation in nude mice (0%; 0/24) was lower than in NSG mice (20%; 23/115; p < 0.05). PDXs derived using both strains maintained histologic and gene expression profiles across passages. Lenvatinib treatment (mean %Δvtumor: -33%) significantly reduced tumor growth as compared to vehicle treatment (mean %Δvtumor: 190%; p < 0.0001).

CONCLUSIONS

Nude mice are a superior platform than NSG mice for generating PDXs from gastric cancer patients. Lenvatinib showed promising antitumor activity in PDXs established from a diverse Western patient population and warrants further investigation in gastric cancer.

Immunotherapy for Esophageal Cancer: State-of-the Art in 2021

The management of esophageal cancer (EC) has experienced manifold changes during the last decades. Centralization of EC treatment has been introduced in many countries, subsequently allowing the development of specialized high-volume centers. Minimal invasive surgery has replaced open surgery in many centers, whereas more potent systemic treatments have been introduced in clinical practice. Newer chemotherapy regimens increase long-term survival. Nevertheless, the overall survival of EC patients remains dismal for advanced tumor stages. In this direction, a wide range of targeted biologic agents (immunotherapy) is currently under assessment. Anti- Human Epidermal Growth Factor Receptor-2 (HER-2) monoclonal antibodies are used in HER2 (+) tumors, predominantly well-differentiated adenocarcinomas, and are currently assessed in the neoadjuvant setting (TRAP, INNOVATION trials). Immune checkpoint inhibitors Nivolumab (ATTRACTION-03) and pembrolizumab (KEYNOTE-181), have demonstrated a survival benefit compared with conventional chemotherapy in heavily pre-treated progressive disease. More recently, CheckMate-577 showed very promising results for nivolumab in a curative adjuvant setting, improving disease-free survival mainly for esophageal squamous cell carcinoma. Several ongoing trials are investigating novel targeted agents in the preoperative setting of locally advanced EC. In addition, other immunomodulatory approaches such as peptide vaccines and tumor infiltrating lymphocytes (TILs) are currently under development and should be increasingly integrated into clinical practice.

Textbook Outcome and Survival in Patients With Gastric Cancer: An Analysis of the Population Registry of Esophageal and Stomach Tumours in Ontario (PRESTO)

OBJECTIVE

To examine the association between Textbook Outcome (TO)-a new composite quality measurement-and long-term survival in gastric cancer surgery.

BACKGROUND

Single-quality indicators do not sufficiently reflect the complex and multifaceted nature of perioperative care in patients with gastric adenocarcinoma.

METHODS

All patients undergoing gastrectomy for nonmetastatic gastric adenocarcinoma registered in the Population Registry of Esophageal and Stomach Tumours of Ontario (PRESTO) between 2004 and 2015 were included. TO was defined according to negative margins; >15 lymph nodes sampled; no severe complications; no re-interventions; no unplanned ICU admission; length of stay ≤21 days; no 30-day readmission; and no 30-day mortality. Three-year survival was estimated using the Kaplan-Meier method. A marginal multivariable Cox proportional-hazards model was used to estimate the association between achieving TO metrics and long-term survival. E-value methodology was used to assess for risk of residual confounding.

RESULTS

Of the 1836 patients included in this study, 402 (22%) achieved all TO metrics. TO patients had a higher 3-year survival rate compared to non-TO patients (75% vs 55%, log-rank P < 0.001). After adjustments for covariates and clustering within hospitals, TO was associated with a 41% reduction in mortality (adjusted hazards ratio 0.59, 95% confidence interval 0.48, 0.72, P < 0.001). These results were robust to potential residual confounding.

CONCLUSIONS

Achieving TO is strongly associated with improved long-term survival in gastric cancer patients and merits further focus in surgical quality improvement efforts.

Laparoscopic gastrectomy for gastric cancer: has the time come for considered it a standard procedure?

Radical gastrectomy with an adequate lymphadenectomy is the main procedure which makes it possible to cure patients with resectable gastric cancer. A number of randomized controlled trials and meta-analysis provide phase III evidence that laparoscopic gastrectomy is technically safe and that it yields better short-term outcomes than conventional open gastrectomy for early-stage gastric cancer. At present, laparoscopic gastrectomy is considered a standard procedure for early-stage gastric cancer, especially in Asian countries. On the other hand, the use of minimally invasive techniques is still controversial for the treatment of more advanced tumours, principally due to existing concerns about its oncological adequacy and capacity to carry out an adequately extended lymphadenectomy. Additional high-quality studies comparing laparoscopic gastrectomy versus open gastrectomy for gastric cancer have been recently published, in particular concerning the latest results obtained by laparoscopic approach to advanced gastric cancer. It seems very useful to update the review of literature in light of these new evidences for this subject and draw some considerations.

Prognostic value of tumor markers and ctDNA in patients with resectable gastric cancer receiving perioperative treatment: results from the CRITICS trial

AIM

To evaluate the prognostic value of tumor markers in a European cohort of patients with resectable gastric cancer.

METHODS

We performed a post hoc analysis of the CRITICS trial, in which 788 patients received perioperative therapy. Association between survival and pretreatment CEA, CA 19-9, alkaline phosphatase, neutrophils, hemoglobin and lactate dehydrogenase were explored in uni- and multivariable Cox regression analyses. Likelihoods to receive potentially curative surgery were investigated for patients without elevated tumor markers versus one of the tumor markers elevated versus both tumor markers elevated. The association between tumor markers and the presence of circulating tumor DNA (ctDNA) was explored in 50 patients with available ctDNA data.

RESULTS

In multivariable analysis, in which we corrected for allocated treatment and other baseline characteristics, elevated pretreatment CEA (HR 1.43; 95% CI 1.11-1.85, p < 0.001) and CA 19-9 (HR 1.79; 95% CI 1.42-2.25, p < 0.001) were associated with worse OS. Likelihoods to receive potentially curative surgery were 86%, 77% and 60% for patients without elevated tumor marker versus either elevated CEA or CA 19-9 versus both elevated, respectively (p < 0.001). Although both preoperative presence of ctDNA and tumor markers were prognostic for survival, no association was found between these two parameters.

CONCLUSION

CEA and CA 19-9 were independent prognostic factors for survival in a large cohort of European patients with resectable gastric cancer. No relationship was found between tumor markers and ctDNA. These factors could potentially guide treatment choices and should be included in future trials to determine their definitive position.

TRIAL REGISTRATION

ClinicalTrial.gov identifier: NCT00407186. EudraCT number: 2006-00413032.

Dynamic Prediction of Survival after Curative Resection of Gastric Adenocarcinoma: A landmarking-based analysis

BACKGROUND

Accurate estimation of survival and recurrence are important to inform decisions regarding therapy and surveillance. We sought to design and validate a dynamic prognostic model for patients undergoing resection for gastric adenocarcinoma.

METHODS

Patients who underwent curative-intent surgery for gastric adenocarcinoma between 2000 and 2020 were identified using a multi-institutional database. Landmark analysis was used to create dynamic OS and DFS prediction models. Model performance was internally cross-validated via bootstrap resampling.

RESULTS

Among 895 patients, 507 (57.2%) patients underwent partial gastrectomy (n = 507, 57.2%) while 380 (42.8%) had total gastrectomy. Median tumor size was 40 mm (IQR: 25-65), most tumors were located in the antrum (n = 344, 39.5%) and infiltrated the subserosa (T3 tumors: n = 283, 31.9%) or serosa (T4 tumors: n = 253, 28.5%); lymph node metastasis occurred in 528 (59.1%) patients. Median OS and DFS were 17.5 (IQR: 7.5-42.8) and 14.3 months (IQR: 6.5-39.9), respectively. The impact of age, sex, preoperative comorbidities, tumor size and location, extent of lymphadenectomy and total number of lymph nodes examined, Lauren class, T and N category, postoperative complications, and tumor recurrence varied over time (all p < 0.05). An online tool to predict dynamic OS and DFS based on patient survival relative to time survived was developed and made available for clinical use. Discrimination ability of OS and DFS was excellent (C-index: 0.84 and 0.86, respectively) and calibration plots revealed good prediction.

CONCLUSIONS

An online dynamic prognostic tool was developed and validated to predict OS and DFS following resection of gastric adenocarcinoma. Landmark analysis to predict long-term outcomes based on follow-up time may be helpful to surgeons and patients.

Immunogenomic Landscape and Immune-Related Gene-Based Prognostic Signature in Asian Gastric Cancer

Background

Asians have the highest incidence of gastric cancer (GC), and the prognosis of Asian GC is poor. Furthermore, the therapeutics for Asian GC is limited because of genetic heterogeneity and screening difficulty at the early stage. This study aimed to develop an immune-related gene (IRG)-based prognostic signature and to explore prognosis-related regulatory mechanism and therapeutic target for Asian GC.

Methods

To elucidate the prognostic value of IRGs in Asian GC, a comprehensive analysis of IRG expression profiles and overall survival times in 364 Asian GC patients from the Asian Cancer Research Group (ACRG) and The Cancer Genome Atlas (TCGA) databases was performed, and a novel prognostic index was established. To further explore regulatory prognosis mechanisms and therapeutic targets, a tumor immunogenomic landscape analysis, including stromal and immune subcomponents, cell types, panimmune gene sets, and immunomodulatory genes, was performed.

Result

Our analysis allowed the creation of an optimal risk assessment model, the Asian-specific IRG-based prognostic index (ASIRGPI), which showed a high accuracy in predicting survival in Asian GC. We also developed an ASIRGPI-based nomogram to predict the 3- and 5-year overall survival (OS) of Asian GC patients. The impact of the ASIRGPI on the worse prognosis of Asian GC was possibly related to the stromal component remodeling. Specifically, TGFβ gene sets were significantly associated with the ASIRGPI and worse prognosis. Immunomodulatory gene analysis further revealed that TGFβ1 and EDNRB may be the novel potential therapeutic targets for Asian GC.

Conclusions

As a tumor microenvironment-relevant gene set-based prognostic signature, the ASIRGPI model provides an effective approach for evaluating the prognosis of Asian GC and may even prolong OS by enabling the selection of individualized therapy with the novel targets.

Laparoscopic vs Open Distal Gastrectomy for Locally Advanced Gastric Cancer: Five-Year Outcomes From the CLASS-01 Randomized Clinical Trial

Importance

It is not clear whether laparoscopic and open distal gastrectomy produce similar outcomes among patients with locally advanced gastric cancer. Data from a multicenter, randomized clinical trial (Chinese Laparoscopic Gastrointestinal Surgical Study [CLASS]-01) showed that laparoscopic distal gastrectomy did not result in inferior disease-free survival at 3 years compared with open distal gastrectomy.

Objective

To report 5-year overall survival data from the CLASS-01 trial of laparoscopic vs open distal gastrectomy among patients with locally advanced gastric cancer.

Design, Setting, and Patients

This was a noninferiority, open-label, randomized clinical trial conducted at 14 centers in China. A total of 1056 eligible patients with clinical stage T2, T3, or T4a gastric cancer without bulky nodes or distant metastases were enrolled from September 12, 2012, to December 3, 2014. Final follow-up was on December 31, 2019.

Interventions

Participants were randomized in a 1:1 ratio after stratification by site, age, cancer stage, and histologic features to undergo either laparoscopic distal gastrectomy (n = 528) or open distal gastrectomy (n = 528) with D2 lymphadenectomy.

Main Outcomes and Measures

The 5-year overall survival rates were updated to compare laparoscopic distal gastrectomy with open distal gastrectomy. All analyses were performed on an intention-to-treat basis. In addition, per-protocol and as-treated analyses were performed for overall survival.

Results

Data from 1039 patients (726 men [69.9%]; mean [SD] age, 56.2 [10.7] years) who received curative therapy were analyzed. At 5 years, the overall survival rates were 72.6% in the laparoscopic distal gastrectomy group and 76.3% in the open distal gastrectomy group (log-rank P = .19; hazard ratio, 1.17; 95% CI, 0.93-1.48; P = .19). After comparison for competing risk events, gastric cancer-related deaths (hazard ratio, 1.14; 95% CI, 0.87-1.49; P = .34) and deaths from other causes (hazard ratio, 1.23; 95% CI, 0.74-2.05; P = .42) did not differ significantly between groups. Overall rates of survival did not differ significantly between groups with each tumor stage.

Conclusions and Relevance

This study found that laparoscopic distal gastrectomy with D2 lymphadenectomy performed by experienced surgeons in high-volume specialized institutions resulted in similar 5-year overall survival compared with open distal gastrectomy among patients with locally advanced gastric cancer.

Trial Registration

ClinicalTrials.gov Identifier: NCT01609309.

Long Non-Coding RNA NRON promotes Tumor Proliferation by regulating ALKBH5 and Nanog in Gastric Cancer

Long non-coding RNAs (lncRNAs) act as tumor suppressors or oncogenes in tumor development and progression. In this study, we explored the expression and biological role of lncRNA NRON in gastric cancer (GC). We observed that lncNRON was upregulated in GC tissues and cell lines, and high lncNRON expression was associated with malignant features and poor prognosis in GC patients. LncNRON was found to promote the proliferation and tumorigenicity of GC cells. Mechanistically, lncNRON exerted its oncogenic functions by binding to the N6-methyladenosine eraser ALKHB5 and mediating Nanog mRNA decay. In conclusion, our results suggest that lncNRON serves as an oncogenic lncRNA in GC and thus may be a promising prognostic factor and potential therapeutic target for GC patients.

Disparities and survival in newly diagnosed gastric cancer in Hispanic patients in the United States: a propensity score matched analysis

Background

The burden of gastric cancer involving Hispanic patients in the United States is growing as both the population and the incidence of gastric cancer in this group increases. This burden is compounded by presentation with advanced disease and socioeconomic challenges shaping cancer care. We sought to describe the demographics, socioeconomic factors, treatment, and survival experience of Hispanic patients with gastric adenocarcinoma.

Methods

Patients with gastric adenocarcinoma diagnosed between 2004 and 2015 (n=90,737) in the National Cancer Database were retrospectively identified. Patients of Hispanic ethnicity were compared against non-Hispanic white patients. Surgical cohort was further analyzed, and 1:1 propensity score matching was used to balance covariates between Hispanic and non-Hispanic white surgical patients. Survival was compared using Kaplan-Meier method. Cox regression was used to determine prognostic factors for survival.

Results

Compared to non-Hispanic white patients, Hispanic patients are more likely to be younger, female, and healthier. They were more likely to be uninsured, reside in poorer neighborhoods and reside in areas with lower rates of education. Hispanic patients were more likely to live in a metropolitan area, travel shorter distances for healthcare, and receive treatment at an academic and high volume centers. Hispanic patients were more likely to have higher stage disease presentation, higher grade tumors, lymphovascular invasion, and poorly cohesive adenocarcinoma. Hispanic patients were more likely to receive surgery, but less likely to receive adjuvant therapy. In Cox regression of all patients, unmatched surgical patients, and matched surgical patients, Hispanic ethnicity was an independent prognostic factor of improved survival.

Conclusions

Hispanic patients with gastric adenocarcinoma present with several unfavorable clinicopathologic and socioeconomic factors. Paradoxically, these patients demonstrate improved survival. Further study is warranted to characterize disease biology in this population.

Evaluation of Human Epidermal Growth Factor Receptor 2 Overexpression, Clinicopathological Characteristics, and Factors Affecting Survival in Gastric Cancer

Objectives:

The objective of the study was to evaluate the human epidermal growth factor receptor 2 (HER2) overexpression, clinicopathological features, and factors affecting survival in patients with gastric cancer.

Methods:

The study is a retrospective study conducted with 128 cases of gastric cancer who were admitted to Şişli Hamidiye Etfal Training and Research Hospital between 2005 and 2012. Patients’ demographic characteristics, performance score, tumor localization, information about surgery, HER2 measurements, histopathological characteristics, stage, treatment features, metastasis sites, and overall survival time were obtained from medical records. Immunohistochemical analysis was performed for HER2 scoring.

Results:

There were 89 (69.5%) men and 39 (30.5%) women in the study group, and the median age of the patients was 64 years. The median survival time of the patients was 24.43 months. The survival rate of the patients was calculated as 35.4±5.9%. Overall survival time was found to be shorter in the group with higher HER2 levels and also those with advanced-stage cancer. The survival rate was found to be significantly lower in patients with perineural invasion and advanced stage. However, the survival rate was not associated with lymphovascular invasion, surgical margin involvement, and HER2 levels. In the multivariate Cox Regression analysis performed to assess the effects of gender, histological subtype, stage, and surgical margin on overall survival, disease stage was found to be the only factor effective on survival. Gender, histological subtype, and the surgical margin did not affect prognosis.

Conclusion:

The survival rate in gastric cancers was found to be lower in those with advanced-stage disease. Higher HER2 level and the disease stage were associated with shorter overall survival time.

Multidisciplinary treatment strategy for locally advanced gastric cancer: A systematic review

BACKGROUND

Multidisciplinary management of patients with locally advanced gastric cancer (LAGC) remains unstandardized worldwide. We performed a systemic review to summarize the advancements, regional differences, and current recommended multidisciplinary treatment strategies for LAGC.

METHODS

Eligible studies were identified through a comprehensive search of PubMed, Web of Science, Cochrane Library databases and Embase. Phase 3 randomized controlled trials which investigated survival of patients with LAGC who underwent gastrectomy with pre-/perioperative, postoperative chemotherapy, or chemoradiotherapy were included.

RESULTS

In total, we identified 11 studies of pre-/perioperative chemotherapy, 38 of postoperative chemotherapy, and 14 of chemoradiotherapy. In Europe and the USA, the current standard of care is perioperative chemotherapy for patients with LAGC using the regimen of 5-FU, folinic acid, oxaliplatin and docetaxel (FLOT). In Eastern Asia, upfront gastrectomy and postoperative chemotherapy is commonly used. The S-1 monotherapy or a regimen of capecitabine and oxaliplatin (CapOx) are used for patients with stage II disease, and the CapOx regimen or the S-1 plus docetaxel regimen are recommended for those with stage III Gastric cancer (GC). The addition of postoperative radiotherapy to peri- or postoperative chemotherapy is currently not recommended. Additionally, clinical trials testing targeted therapy and immunotherapy are increasingly performed worldwide.

CONCLUSIONS

Recent clinical trials showed a survival benefit of peri-over postoperative chemotherapy and chemoradiotherapy. As such, this strategy may have a potential as a global standard for patients with LAGC. Outcome of the ongoing clinical trials is expected to establish the global standard of multidisciplinary treatment strategy in patients with LAGC.

Current treatment and recent progress in gastric cancer

Gastric cancer is not a top-10 malignancy in the United States but represents one of the most common causes of cancer death worldwide. Biological differences between tumors from Eastern and Western countries add to the complexity of identifying standard-of-care therapy based on international trials. Systemic chemotherapy, radiotherapy, surgery, immunotherapy, and targeted therapy all have proven efficacy in gastric adenocarcinoma; therefore, multidisciplinary treatment is paramount to treatment selection. Triplet chemotherapy for resectable gastric cancer is now accepted and could represent a plateau of standard cytotoxic chemotherapy for localized disease. Classification of gastric cancer based on molecular subtypes is providing an opportunity for personalized therapy. Biomarkers, in particular microsatellite instability (MSI), programmed cell death ligand 1 (PD-L1), human epidermal growth factor receptor 2 (HER2), tumor mutation burden, and Epstein-Barr virus, are increasingly driving systemic therapy approaches and allowing for the identification of populations most likely to benefit from immunotherapy and targeted therapy. Significant research opportunities remain for the less differentiated histologic subtypes of gastric adenocarcinoma and those without markers of immunotherapy activity.

[Evidence in minimally invasive oncological gastric surgery]

BACKGROUND

The aim of this study was to systematically review the current evidence on laparoscopic and robotic distal and total gastrectomy in comparison to open surgery.

MATERIAL AND METHODS

A systematic search of EMBASE and PubMed was conducted and 197 randomized (RCT) and non-randomized (non-RCT) studies were identified. An evaluation of early gastric cancer (EGC) and advanced (AGC) gastric cancer was carried out.

RESULTS

For EGC and laparoscopic distal resection (LDG) and total gastrectomy (LTG) a total of 10 RCT and 6 non-RCT, including 4329 patients (laparoscopic 2010 vs. open 2319) were identified. At a high evidence level (1+, 1++) there was no significant difference in terms of feasibility, intraoperative outcome and oncological quality, mortality and long-term oncological outcome compared to open gastrectomy (OG). After LDG and LTG patients showed a significantly faster early postoperative recovery and lower total morbidity. In contrast, the operation times were significant longer compared to ODG and OTG. For distal AGC and LDG in 6 RCT, including 2806 patients (LDG 1410 vs. ODG 1369) comparable results could be found also with a high evidence level (1++). The evidence for LTG in cases of AGC was lower (2-, 2+). Currently ,only 6 non-RCT with a total of 1090 patients (LTG 539 vs. OTG 551) are available, which showed comparable results to LDG but further high-quality RCTs are necessary. Robotic gastrectomy (RG) is currently being evaluated. According to the first studies RG for EGC seems to be equivalent to LDG; however, the evidence is currently low (3 to 2-).

Short-term outcomes of laparoscopic versus open total gastrectomy after neoadjuvant chemotherapy: a cohort study using the propensity score matching method

Background

Until now, little is known about the benefit of laparoscopic total gastrectomy (LTG) after neoadjuvant chemotherapy (NACT). This study was designed to compare the safety and efficacy of the LTG versus the open total gastrectomy (OTG) approach after NACT treatment in patients with advanced gastric cancer (AGC).

Methods

This study involved a cohort of 145 patients with AGC who underwent total gastrectomy after NACT at our centre between April 2013 and August 2018 including 24 cases of LTG and 121 OTG. The baseline characteristics were matched based on 1:2 balanced propensity score-matching method.

Results

Sixty-nine marched cases were finally analysed (23 LTG vs. 46 OTG). All patients underwent R0 resection. Compared to the OTG group, the LTG group had a longer surgery duration (P<0.001), but a shorter incision length (P<0.001) and less intravenous patient-controlled analgesia (IV-PCA) time after surgery (P=0.027). No statistical differences were observed in terms of blood loss, retrieved lymph nodes (LNs), resection margin, length of stay, postoperative pain intensity, and complications (P>0.05).

Conclusions

LTG had comparable safety and histological findings to OTG after NACT in the perioperative period; however, LTG is less invasive and patients can benefit from less IV-PCA use. Further research is needed to investigate long-term effects.

Keywords

Gastric cancer (GC); neoadjuvant chemotherapy (NACT); safety; laparoscopic technique.

Omentum preservation as an oncologically comparable and surgically superior alternative to total omentectomy during radical gastrectomy for T3-T4 gastric cancer

BACKGROUND

Total omentectomy has conventionally been performed and has been regarded as standard procedure in radical gastrectomy for cancer. However, omentum preservation is the preferred procedure during minimally invasive surgery, without sufficient evidence of oncological safety, especially for T3-T4 gastric cancer.

METHOD

A total of 3,510 patients who underwent radical gastrectomy for T3-T4 gastric cancer between January 2003 and December 2015 were reviewed, retrospectively. After propensity score matching, 225 patients in the omentum preservation group were compared with 225 patients in the total omentectomy group. The primary outcome was 5-year overall survival.

RESULTS

The omentum preservation group showed significantly shorter operation time (P = .001) and less blood loss (P = .004) than the total omentectomy group. Shorter operation time was also observed with both open and minimally invasive approaches (P < .001 and P = .007, respectively). The 5-year overall survival rates were 75.4% for the omentum preservation group and 72.6% for the total omentectomy group (log-rank P = .06; hazard ratio 0.7 [95% confidence interval, 0.48-1.01]). The 5-year relapse-free survival was higher in the omentum preservation group (73.8%) than in the total omentectomy group (66.1%), without statistical significance (log-rank P = .09; hazard ratio 0.74 [95% confidence interval, 0.52-1.06]).

CONCLUSION

Regardless of the surgical approach, omentum preservation provided comparable oncologic outcomes with better surgical outcomes, suggesting that this could be an acceptable alternative to total omentectomy for T3-T4 gastric cancer. These findings warrant further investigation in randomized clinical trials.