Evaluation of PET and laparoscopy in STagIng advanced gastric cancer: a multicenter prospective study (PLASTIC-study)

Impact of 18FFDG-PET/CT and Laparoscopy in Staging of Locally Advanced Gastric Cancer: A Cost Analysis in the Prospective Multicenter PLASTIC-Study

BACKGROUND

Unnecessary D2-gastrectomy and associated costs can be prevented after detecting non-curable gastric cancer, but impact of staging on treatment costs is unclear. This study determined the cost impact of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18FFDG-PET/CT) and staging laparoscopy (SL) in gastric cancer staging.

MATERIALS AND METHODS

In this cost analysis, four staging strategies were modeled in a decision tree: (1) 18FFDG-PET/CT first, then SL, (2) SL only, (3) 18FFDG-PET/CT only, and (4) neither SL nor 18FFDG-PET/CT. Costs were assessed on the basis of the prospective PLASTIC-study, which evaluated adding 18FFDG-PET/CT and SL to staging advanced gastric cancer (cT3-4 and/or cN+) in 18 Dutch hospitals. The Dutch Healthcare Authority provided 18FFDG-PET/CT unit costs. SL unit costs were calculated bottom-up. Gastrectomy-associated costs were collected with hospital claim data until 30 days postoperatively. Uncertainty was assessed in a probabilistic sensitivity analysis (1000 iterations).

RESULTS

18FFDG-PET/CT costs were €1104 including biopsy/cytology. Bottom-up calculations totaled €1537 per SL. D2-gastrectomy costs were €19,308. Total costs per patient were €18,137 for strategy 1, €17,079 for strategy 2, and €19,805 for strategy 3. If all patients undergo gastrectomy, total costs were €18,959 per patient (strategy 4). Performing SL only reduced costs by €1880 per patient. Adding 18FFDG-PET/CT to SL increased costs by €1058 per patient; IQR €870-1253 in the sensitivity analysis.

CONCLUSIONS

For advanced gastric cancer, performing SL resulted in substantial cost savings by reducing unnecessary gastrectomies. In contrast, routine 18FFDG-PET/CT increased costs without substantially reducing unnecessary gastrectomies, and is not recommended due to limited impact with major costs.

TRIAL REGISTRATION

NCT03208621. This trial was registered prospectively on 30-06-2017.

Techniques of staging laparoscopy and peritoneal fluid assessment in gastric cancer: a systematic review

BACKGROUND

Staging laparoscopy for gastric cancer is recommended to assess the tumor's locoregional extension and exclude peritoneal disease. As there is no consensus on optimizing the procedure's diagnostic accuracy, we aimed to systematically review the literature on operative techniques, followed by peritoneal lavage fluid assessment in gastric cancer patients. Specifically, we sought to indicate the most common characteristics of the procedure and cytological evaluation.

METHODS

This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The protocol for this systematic review was registered on PROSPERO database (CRD: 42022306746). On September 2022, a search was carried out using Embase, Medline ALL, Cochrane Central Register of Controlled Trials, and Web of Science Core Collection.

RESULTS

The search identified 1632 studies on staging laparoscopy and 2190 studies on peritoneal fluid assessment. Some 212 studies were included. Open Hasson was the method of choice in accessing the peritoneal cavity in 65% of the studies, followed by establishing a pneumoperitoneum at 10-12 mmHg in 52% of reports. Most frequently, the patient was positioned supine (70%), while a 30° scope and three ports were used to assess the peritoneal cavity clockwise (72%, 77%, and 85%, respectively). Right and left upper abdomen quadrants were the predominant area of laparoscopic exploration (both 65%), followed by the primary tumor region (54%), liver and pelvis (both 30%), and small bowel and spleen (19% and 17%, respectively). Regions of peritoneal lavage and aspiration were limited to the pelvis (50%), followed by right and left upper abdomen quadrants (37.5% and 50%, respectively). No studies compared different methods of operative techniques or analysis of ascites/fluid.

CONCLUSIONS

This study indicates a high heterogeneity in the technique of staging laparoscopy and peritoneal fluid assessment in gastric cancer patients. Further research and initiatives to reach a consensus on the standardization of the procedure are warranted.

Incidence, Stage, Treatment, and Survival of Noncardia Gastric Cancer

Importance

Gastric cancer is the fifth most common cancer worldwide, and investigating its incidence, characteristics, treatment, and outcomes over the past decades can help in selecting clinical strategies and future research directions.

Objective

To analyze the trends in incidence, staging, and treatment of gastric cancer.

Design, Setting, and Participants

This nationwide, population-based cohort study included patients diagnosed with noncardia gastric cancer (NCGC) between 1989 and 2021 in the Netherlands.

Main Outcomes and Measures

Differences in tumor characteristics, treatment, and survival were analyzed per fixed time periods (1989-1993, 1994-1998, 1999-2003, 2004-2008, 2009-2013, 2014-2018, and 2019-2021).

Results

In total, 47 014 patients (median [IQR] age, 73 [64-80] years; 28 032 [60%] male patients) were identified with mostly adenocarcinomas of the antrum region (when location was known). Age-standardized incidence decreased from 20.3 to 6.1 per 100 000 person-years between 1989 and 2021. During the study period, unknown T and N stages were recorded less frequently, and metastatic disease was diagnosed more frequently (1989-1993: 2633 of 9493 patients [28%]; 2019-2021: 1503 of 3200 patients [47%] in 2019-2021). Over time, fewer patients with metastatic disease underwent surgery with or without other treatment modalities (68% in 1989-1993 vs 64% in 2019-2021), and palliative chemotherapy in metastatic NCGC increased from 9% to 40%. For patients with nonmetastatic disease, 5-year relative survival improved from 28% (95% CI, 26.5%-29.2%) to 36% (95% CI, 33.5%-37.6%) between 1989 and 2021. For patients with nonmetastatic disease undergoing a resection, 5-year survival increased from 40% (95% CI, 38.3%-41.8%) to 51% (95% CI, 47.9%-53.3%). For patients with metastatic disease, 1-year relative survival increased from 10% (95% CI, 8.7%-11.1%) to 19% (95% CI, 17.2%-21.6%), but 3-year relative survival remained poor at 5% (95% CI, 3.6%-7.5%).

Conclusions and Relevance

In this nationwide cohort study involving 47 014 patients diagnosed with NCGC (1989-2021), the results showed a decrease in incidence, more accurate staging, a shift in treatment modalities, and improved patient survival.

Prognostic Value of [18F]FDG PET Radiomics to Detect Peritoneal and Distant Metastases in Locally Advanced Gastric Cancer-A Side Study of the Prospective Multicentre PLASTIC Study

AIM

To improve identification of peritoneal and distant metastases in locally advanced gastric cancer using [¹⁸F]FDG-PET radiomics.

METHODS

[¹⁸F]FDG-PET scans of 206 patients acquired in 16 different Dutch hospitals in the prospective multicentre PLASTIC-study were analysed. Tumours were delineated and 105 radiomic features were extracted. Three classification models were developed to identify peritoneal and distant metastases (incidence: 21%): a model with clinical variables, a model with radiomic features, and a clinicoradiomic model, combining clinical variables and radiomic features. A least absolute shrinkage and selection operator (LASSO) regression classifier was trained and evaluated in a 100-times repeated random split, stratified for the presence of peritoneal and distant metastases. To exclude features with high mutual correlations, redundancy filtering of the Pearson correlation matrix was performed (r = 0.9). Model performances were expressed by the area under the receiver operating characteristic curve (AUC). In addition, subgroup analyses based on Lauren classification were performed.

RESULTS

None of the models could identify metastases with low AUCs of 0.59, 0.51, and 0.56, for the clinical, radiomic, and clinicoradiomic model, respectively. Subgroup analysis of intestinal and mixed-type tumours resulted in low AUCs of 0.67 and 0.60 for the clinical and radiomic models, and a moderate AUC of 0.71 in the clinicoradiomic model. Subgroup analysis of diffuse-type tumours did not improve the classification performance.

CONCLUSION

Overall, [¹⁸F]FDG-PET-based radiomics did not contribute to the preoperative identification of peritoneal and distant metastases in patients with locally advanced gastric carcinoma. In intestinal and mixed-type tumours, the classification performance of the clinical model slightly improved with the addition of radiomic features, but this slight improvement does not outweigh the laborious radiomic analysis.

Glucose metabolic profiles evaluated by PET associated with molecular characteristic landscape of gastric cancer

BACKGROUND

Although FDG-PET is widely used in cancer, its role in gastric cancer (GC) is still controversial due to variable [¹⁸F]fluorodeoxyglucose ([¹⁸F]FDG) uptake. Here, we sought to develop a genetic signature to predict high FDG-avid GC to plan individualized PET and investigate the molecular landscape of GC and its association with glucose metabolic profiles noninvasively evaluated by [¹⁸F]FDG-PET.

METHODS

Based on a genetic signature, PETscore, representing [¹⁸F]FDG avidity, was developed by imaging data acquired from thirty patient-derived xenografts (PDX). The PETscore was validated by [¹⁸F]FDG-PET data and gene expression data of human GC. The PETscore was associated with genomic and transcriptomic profiles of GC using The Cancer Genome Atlas.

RESULTS

Five genes, PLS1, PYY, HBQ1, SLC6A5, and NAT16, were identified for the predictive model for [¹⁸F]FDG uptake of GC. The PETscore was validated in independent PET data of human GC with qRT-PCR and RNA-sequencing. By applying PETscore on TCGA, a significant association between glucose uptake and tumor mutational burden as well as genomic alterations were identified.

CONCLUSION

Our findings suggest that molecular characteristics are underlying the diverse metabolic profiles of GC. Diverse glucose metabolic profiles may apply to precise diagnostic and therapeutic approaches for GC.

18F-Fludeoxyglucose-Positron Emission Tomography/Computed Tomography and Laparoscopy for Staging of Locally Advanced Gastric Cancer: A Multicenter Prospective Dutch Cohort Study (PLASTIC)

Importance

The optimal staging for gastric cancer remains a matter of debate.

Objective

To evaluate the value of 18F-fludeoxyglucose-positron emission tomography with computed tomography (FDG-PET/CT) and staging laparoscopy (SL) in addition to initial staging by means of gastroscopy and CT in patients with locally advanced gastric cancer.

Design, Setting, and Participants

This multicenter prospective, observational cohort study included 394 patients with locally advanced, clinically curable gastric adenocarcinoma (≥cT3 and/or N+, M0 category based on CT) between August 1, 2017, and February 1, 2020.

Exposures

All patients underwent an FDG-PET/CT and/or SL in addition to initial staging.

Main Outcomes and Measures

The primary outcome was the number of patients in whom the intent of treatment changed based on the results of these 2 investigations. Secondary outcomes included diagnostic performance, number of incidental findings on FDG-PET/CT, morbidity and mortality after SL, and diagnostic delay.

Results

Of the 394 patients included, 256 (65%) were men and mean (SD) age was 67.6 (10.7) years. A total of 382 patients underwent FDG-PET/CT and 357 underwent SL. Treatment intent changed from curative to palliative in 65 patients (16%) based on the additional FDG-PET/CT and SL findings. FDG-PET/CT detected distant metastases in 12 patients (3%), and SL detected peritoneal or locally nonresectable disease in 73 patients (19%), with an overlap of 7 patients (2%). FDG-PET/CT had a sensitivity of 33% (95% CI, 17%-53%) and specificity of 97% (95% CI, 94%-99%) in detecting distant metastases. Secondary findings on FDG/PET were found in 83 of 382 patients (22%), which led to additional examinations in 65 of 394 patients (16%). Staging laparoscopy resulted in a complication requiring reintervention in 3 patients (0.8%) without postoperative mortality. The mean (SD) diagnostic delay was 19 (14) days.

Conclusions and Relevance

This study's findings suggest an apparently limited additional value of FDG-PET/CT; however, SL added considerably to the staging process of locally advanced gastric cancer by detection of peritoneal and nonresectable disease. Therefore, it may be useful to include SL in guidelines for staging advanced gastric cancer, but not FDG-PET/CT.

Staging laparoscopy in patients with advanced gastric cancer: A single center cohort study

BACKGROUND

Most studies exploring the role of staging laparoscopy in gastric cancer are limited by low sample size and are predominantly conducted in Asian countries. This study sets out to determine the value of staging laparoscopy in patients with advanced gastric cancer in a Western population.

METHODS

All patients with gastric cancer from a tertiary referral center without definite evidence of non-curable disease after initial staging, and who underwent staging laparoscopy between 2013 and 2020, were identified from a prospectively maintained database. The proportion of patients in whom metastases or locoregional non-resectability was detected during staging laparoscopy was established. Secondary outcomes included the avoidable surgery rate (detection of non-curable disease during gastrectomy with curative intent) and diagnostic accuracy (sensitivity, specificity, accuracy, negative and positive predictive value).

RESULTS

A total of 216 patients were included. Staging laparoscopy revealed metastatic disease in 46 (21.3 %) patients and a non-resectable tumor in three (1.4 %) patients. During intended gastrectomy, non-curable disease was revealed in 13 (8.6 %) patients. Overall sensitivity, specificity and diagnostic accuracy were 76.6 %, 100 % and 92.6 %, respectively. The positive predictive value was 100 % and the negative predictive value was 90.3 %.

CONCLUSION

Staging laparoscopy is valuable in the staging process of gastric cancer with a high accuracy in detecting non-curable disease, thereby preventing futile treatment and its associated burden.

Synchronous peritoneal metastases of gastric cancer origin: incidence, treatment and survival of a nationwide Dutch cohort

INTRODUCTION

The peritoneum is a predilection site for gastric cancer metastases. Current standard treatment for gastric cancer patients with synchronous peritoneal metastases is palliative systemic therapy. However, its efficacy is largely unknown. The aim of this study was to investigate the incidence, treatment and survival patterns of gastric cancer patients with synchronous peritoneal metastases in the Netherlands.

METHODS

All newly diagnosed gastric adenocarcinoma patients with synchronous peritoneal metastases between 1999 and 2017 were selected from the Netherlands Cancer Registry (NCR). Incidence, treatment and survival patterns were analyzed.

RESULTS

In total, 3,773 patients were identified from the NCR. The incidence of synchronous peritoneal metastases in gastric cancer patients increased from 18% in 2008 to 27% in 2017. The use of systemic therapy increased from 15% in 1999-2002 to 43% in 2013-2017 (p < 0.001). The median survival of the entire cohort did not significantly increase over time. Median survival of patients treated with systemic therapy increased from 7.4 months in 1999-2002 to 9.4 months in 2013-2017 (p = 0.005). In contrast, median survival of patients not treated with systemic therapy decreased from 3.3 months in 1999-2002 to 2.1 months in 2013-2017 (p < 0.001). Some clinical and pathological data such as the extent of the peritoneal metastases were not available.

CONCLUSION

Synchronous peritoneal metastases are increasingly diagnosed in gastric cancer patients. In recent years, more patients were treated with systemic treatment and survival of these patients increased. However, as survival of the entire group did not improve over time, the effect of systemic therapy remains unknown.

Lymph Node Involvement in Advanced Gastric Cancer in the Era of Multimodal Treatment-Oncological and Surgical Perspective

Simple Summary

Gastric cancer (GC) continues to be one of the major oncological challenges on a global scale. The role of neoadjuvant chemotherapy (NAC) in GC is to downstage primary tumour, eliminate potential micrometastases, and increase the chance for radical resection. Although systemic treatment prolongs the survival in advanced GC, persistent lymph node (LN) metastases indicate poor prognosis. Therefore, further identification of prognostic factors after NAC is urgent and could positively influence clinical outcomes. This article aimed to review the actual trends and future perspectives in multimodal therapy of advanced GC, with a particular interest in the post-neoadjuvant pathological nodal stage. Since downstaged and primarily node-negative patients show a similar prognosis, the main target for NAC in advanced GC should be nodal clearance. Adequate staging and personalised perioperative therapy seem to be of great importance in the multimodal treatment of GC.

Abstract

Gastric cancer (GC) continues to be one of the major oncological challenges on a global scale. The role of neoadjuvant chemotherapy (NAC) in GC is to downstage primary tumour, eliminate potential micrometastases, and increase the chance for radical resection. Although systemic treatment prolongs the survival in advanced GC, persistent lymph node (LN) metastases indicate poor prognosis. Further identification of prognostic factors after NAC is urgent and could positively influence clinical outcomes. This article aimed to review the actual trends and future perspectives in multimodal therapy of advanced GC, with a particular interest in the post-neoadjuvant pathological nodal stage. A favourable prognostic impact for ypN0 patients is observed, either due to truly negative LN before the start of therapy or because preoperative therapy achieved a pathologically complete nodal response. Ongoing trials investigating the extent of lymphadenectomy after neoadjuvant therapy will standardise the LN dissection from the multimodal therapy perspective. Since downstaged and primarily node-negative patients show a similar prognosis, the main target for NAC in advanced GC should be nodal clearance. Adequate staging and personalised perioperative therapy seem to be of great importance in the multimodal treatment of GC.

Evaluation of the Implementation of FDG-PET/CT and Staging Laparoscopy for Gastric Cancer in The Netherlands

BACKGROUND

The role of 18F-fluorodeoxyglucose positron emission tomography with computed tomography (FDG-PET/CT) and staging laparoscopy (SL) has increased in the preoperative staging of gastric cancer. Dutch national guidelines have recommended the use of FDG-PET/CT and SL for patients with locally advanced tumors since July 2016.

OBJECTIVE

The aim of this study was to evaluate the implementation of FDG-PET/CT and SL in The Netherlands.

METHODS

Between 2011 and 2018, all patients who underwent surgery for gastric cancer were included from the Dutch Upper GI Cancer Audit. The use of FDG-PET/CT and SL was evaluated before and after revision of the Dutch guidelines. Outcomes included the number of non-curative procedures (e.g. palliative and futile procedures) and the association of FDG-PET/CT and SL, with waiting times from diagnosis to the start of treatment.

RESULTS

A total of 3310 patients were analyzed. After July 2016, the use of FDG-PET/CT (23% vs. 61%; p < 0.001) and SL (21% vs. 58%; p < 0.001) increased. FDG-PET/CT was associated with additional waiting time to neoadjuvant therapy (4 days), as well as primary surgical treatment (20 days), and SL was associated with 8 additional days of waiting time to neoadjuvant therapy. Performing SL or both modalities consecutively in patients in whom it was indicated was not associated with the number of non-curative procedures.

CONCLUSION

During implementation of FDG-PET/CT and SL after revision of the guidelines, both have increasingly been used in The Netherlands. The addition of these staging methods was associated with increased waiting time to treatment. The number of non-curative procedures did not differ after performing none, solely one, or both staging modalities.

Opportunities in cancer imaging: a review of oesophageal, gastric and colorectal malignancies

The incidence of gastrointestinal (GI) malignancy is increasing worldwide. In particular, there is a concerning rise in incidence of GI cancer in younger adults. Direct endoscopic visualisation of luminal tumour sites requires invasive procedures, which are associated with certain risks, but remain necessary because of limitations in current imaging techniques and the continuing need to obtain tissue for diagnosis and genetic analysis; however, management of GI cancer is increasingly reliant on non-invasive, radiological imaging to diagnose, stage, and treat these malignancies. Oesophageal, gastric, and colorectal malignancies require specialist investigation and treatment due to the complex nature of the anatomy, biology, and subsequent treatment strategies. As cancer imaging techniques develop, many opportunities to improve tumour detection, diagnostic accuracy and treatment monitoring present themselves. This review article aims to report current imaging practice, advances in various radiological modalities in relation to GI luminal tumour sites and describes opportunities for GI radiologists to improve patient outcomes.

Multidisciplinary team consultation for resectable Gastric Cancer: A propensity score matching analysis

Purpose: Previous studies proposed that the multidisciplinary team (MDT) consultation could improve tumor staging accuracy and outcomes of patients with gastric malignancy. However, evidence-based reports remain limited. This study aimed to determine the effectiveness of MDT for tumor staging accuracy and outcomes of patients with resectable gastric cancer, and to explore the potential factors affecting its effectiveness. Methods: This retrospective study enrolled 719 gastric cancer patients who underwent gastrectomy in our hospital. After propensity score matching, 378 patients were selected, including 189 in the non-MDT group and 189 in the MDT group. Data regarding baseline characteristics, staging, treatments, and survival were analyzed. Results: The data showed that the staging accuracy in the MDT group and non-MDT group was comparable (53% vs 61% for T stage, 46.1% vs 35.3% for N stage, and 78.3% vs 78.7% for M stage). The MDT group had a higher proportion of preoperative chemotherapy (39.2% vs 28%, p=0.03) and laparoscopic surgery (82.5% vs 72%, p=0.02) than the non-MDT group. However, the achievement of R0 resection was similar in the two groups (93.7% vs 88.9%, p=0.73). There was no significant difference in the 1-year and 3-year overall survival rates between the two groups. Moreover, we observed poor patient compliance when the MDT recommended further examinations, radiotherapy, or chemotherapy before surgical interventions. Conclusion: MDT consultation has limited effects on improving the staging accuracy and treatment outcomes including survival of patients with resectable gastric cancer. Poor patient compliance may be a factor affecting the effectiveness of MDT consultation.

Failure to Cure in Patients Undergoing Surgery for Gastric Cancer: A Nationwide Cohort Study

Background

This study aimed to describe the incidence of failure to cure (a composite outcome measure defined as surgery not meeting its initial aim), and the impact of hospital variation in the administration of neoadjuvant therapy on this outcome measure.

Methods

All patients in the Dutch Upper Gastrointestinal Cancer Audit undergoing curatively intended gastric cancer surgery in 2011–2019 were included. Failure to cure was defined as (1) ‘open-close’ surgery; (2) irradical surgery (R1/R2); or (3) 30-day/in-hospital mortality. Case-mix-corrected funnel plots, based on multivariable logistic regression analyses, investigated hospital variation. The impact of a hospital’s tendency to administer neoadjuvant chemotherapy on the heterogeneity in failure to cure between hospitals was assessed based on median odds ratios and multilevel logistic regression analyses.

Results

Some 3862 patients from 28 hospitals were included. Failure to cure was noted in 22.3% (hospital variation: 14.5–34.8%). After case-mix correction, two hospitals had significantly higher-than-expected failure to cure rates, and one hospital had a lower-than-expected rate. The failure to cure rate was significantly higher in hospitals with a low tendency to administer neoadjuvant chemotherapy. Approximately 29% of hospital variation in failure to cure could be attributed to different hospital policies regarding neoadjuvant therapy.

Conclusions

Failure to cure has an incidence of 22% in patients undergoing gastric cancer surgery. Higher failure to cure rates were seen in centers administering less neoadjuvant chemotherapy, which confirms the Dutch guideline recommendation on the administration of neoadjuvant chemotherapy. Failure to cure provides short loop feedback and can be used as a quality indicator in surgical audits.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-020-09510-6.

Anti-tumor activity of resveratrol against gastric cancer: a review of recent advances with an emphasis on molecular pathways

Gastric cancer (GC) is one of the most common cancers with high malignancy. In spite of the great development in diagnostic tools and application of anti-tumor drugs, we have not witnessed a significant increase in the survival time of patients with GC. Multiple studies have revealed that Wnt, Nrf2, MAPK, and PI3K/Akt signaling pathways are involved in GC invasion. Besides, long non-coding RNAs and microRNAs function as upstream mediators in GC malignancy. GC cells have acquired resistance to currently applied anti-tumor drugs. Besides, combination therapy is associated with higher anti-tumor activity. Resveratrol (Res) is a non-flavonoid polyphenol with high anti-tumor activity used in treatment of various cancers. A number of studies have demonstrated the potential of Res in regulation of molecular pathways involved in cancer malignancy. At the present review, we show that Res targets a variety of signaling pathways to induce apoptotic cell death and simultaneously, to inhibit the migration and metastasis of GC cells.

Advances in the surgical management of gastric and gastroesophageal junction cancer

Since Theodore Billroth and Cesar Roux perfected the methods of post-gastrectomy reconstruction in the late 19^th century, surgical management of gastric and gastroesophageal cancer has made incremental progress. The majority of patients with localized disease are treated with perioperative combination chemotherapy or neoadjuvant chemoradiation. Staging laparoscopy before initiation of treatment or before surgical resection has improved staging accuracy and can drastically inform treatment decisions. The longstanding and contentious debate on the optimal extent of lymph node dissection for gastric cancer appears to have settled in favor of D2 dissection with the recently published 15-year follow-up of the Dutch randomized trial. Minimally invasive gastric and gastroesophageal resections are performed routinely in most centers affording faster recovery and equivalent oncologic outcomes. Pylorus-preserving distal (central) gastrectomy has emerged as a less invasive, function-preserving option for T1N0 middle-third gastric cancers, while randomized data on its oncologic adequacy are pending. Multi-visceral resections and cytoreductive surgery with hyperthermic intraperitoneal chemotherapy has been utilized selectively for patients with locally advanced tumors who have demonstrated disease control on preoperative chemotherapy. This review summarizes the current standard of surgical care for gastroesophageal junction and gastric cancer as well as highlights recent and upcoming advances to the field.

Staging laparoscopy in gastric cancer surgery. A population-based cohort study in patients undergoing gastrectomy with curative intent

BACKGROUND

Studies on the value of a staging laparoscopy in detecting metastases in gastric cancer patients show great variation. This study investigates the avoidable surgery rate in patients with and without a staging laparoscopy scheduled for surgery with curative intent.

METHODS

This population-based cohort study included all patients with an intentional resection for a potentially curable gastric adenocarcinoma, between 2011 and 2016, registered in the Dutch Upper GI Cancer audit. Patients with and without a staging laparoscopy were compared. The primary outcome was the avoidable surgery rate (detection of metastases and/or locoregional non-resectable tumor during intentional gastrectomy). Secondary outcomes were the negative predictive value, postoperative morbidity and pathology parameters.

RESULTS

2849 patients who underwent an intentional gastrectomy were included. 414 of 2849 (14.5%) patients underwent a staging laparoscopy before initiation of treatment. The avoidable surgery rate was 16.2% in the staging laparoscopy group, compared to 8.5% in the non-staging group (P < 0.001), resulting in a negative predictive value of 83.8%. The avoidable surgery rate remained significantly different after correction for possible confounders. The main reason for not executing the gastrectomy was the presence of distant metastasis in both groups. cT and cN stage were significantly higher in patients who underwent a staging laparoscopy.

CONCLUSIONS

The staging laparoscopy group had a higher cTN and pTN stage, implicating selection of patients with more advanced disease for a staging laparoscopy. Despite the staging laparoscopy, a higher rate of avoidable surgery was found, suggesting a low sensitivity for detecting metastases or locoregional non-resectability in this patient group.

The additive value of restaging-CT during neoadjuvant chemotherapy for gastric cancer

INTRODUCTION

Computed tomography (CT) is used for restaging of gastric cancer patients during neoadjuvant chemotherapy (NAC). The treatment strategy could be altered after detection of distant interval metastases, possibly leading to a reduction in unnecessary chemotherapy cycles, its related toxicity, and surgical procedures. The aim of this study was to evaluate the additive value of restaging-CT during NAC in guiding clinical decision making in gastric cancer.

MATERIALS AND METHODS

This retrospective, multicenter cohort study identified all patients with surgically resectable gastric adenocarcinoma (cT1-4a-x, N0-3-x, M0-x), who started NAC with curative intent. Restaging-CT was performed after 2 out of 3 cycles of NAC. The primary outcome was treatment alterations made based on restaging-CT by a multidisciplinary tumor board. Confirmation of metastases was obtained by surgery or biopsy.

RESULTS

Between 2007 and 2015, CT-restaging was performed in 122 out of 152 included patients and timed after 2 cycles (n = 76) or after 3 cycles (n = 46) of NAC. Restaging-CT revealed a metastasis in 1 out of 122 restaged patients (1%) after which surgical resection was omitted, whereas 4 patients (3%) with distant interval metastases were not identified by restaging-CT and underwent a futile laparotomy. In 5 out of 76 patients (7%) disease progression was detected while undergoing NAC, leading to omission of the 3rd cycle of chemotherapy.

CONCLUSION

The additive value of restaging-CT during NAC in gastric cancer is limited in guiding clinical decision making and therefore not recommended. Further studies may identify subgroups that may benefit of alternative diagnostic modalities.

Establishment of a [18F]-FDG-PET/MRI Imaging Protocol for Gastric Cancer PDX as a Preclinical Research Tool

Purpose

The utility of 18-fluordesoxyglucose positron emission tomography ([¹⁸F]-FDG-PET) combined with computer tomography or magnetic resonance imaging (MRI) in gastric cancer remains controversial and a rationale for patient selection is desired. This study aims to establish a preclinical patient-derived xenograft (PDX) based [¹⁸F]-FDG-PET/MRI protocol for gastric cancer and compare different PDX models regarding tumor growth and FDG uptake.

Materials and Methods

Female BALB/c nu/nu mice were implanted orthotopically and subcutaneously with gastric cancer PDX. [¹⁸F]-FDG-PET/MRI scanning protocol evaluation included different tumor sizes, FDG doses, scanning intervals, and organ-specific uptake. FDG avidity of similar PDX cases were compared between ortho- and heterotopic tumor implantation methods. Microscopic and immunohistochemical investigations were performed to confirm tumor growth and correlate the glycolysis markers glucose transporter 1 (GLUT1) and hexokinase 2 (HK2) with FDG uptake.

Results

Organ-specific uptake analysis showed specific FDG avidity of the tumor tissue. Standard scanning protocol was determined to include 150 μCi FDG injection dose and scanning after one hour. Comparison of heterotopic and orthotopic implanted mice revealed a long growth interval for orthotopic models with a high uptake in similar PDX tissues. The H-score of GLUT1 and HK2 expression in tumor cells correlated with the measured maximal standardized uptake value values (GLUT1: Pearson r=0.743, P=0.009; HK2: Pearson r=0.605, P=0.049).

Conclusions

This preclinical gastric cancer PDX based [¹⁸F]-FDG-PET/MRI protocol reveals tumor specific FDG uptake and shows correlation to glucose metabolic proteins. Our findings provide a PET/MRI PDX model that can be applicable for translational gastric cancer research.

BRAZILIAN GASTRIC CANCER ASSOCIATION GUIDELINES (PART 1): AN UPDATE ON DIAGNOSIS, STAGING, ENDOSCOPIC TREATMENT AND FOLLOW-UP

BACKGROUND

The II Brazilian Consensus on Gastric Cancer by the Brazilian Gastric Cancer Association (ABCG) was recently published. On this occasion, several experts in gastric cancer expressed their opinion before the statements presented.

AIM

To present the ABCG Guidelines (part 1) regarding the diagnosis, staging, endoscopic treatment and follow-up of gastric cancer patients.

METHODS

To forge these Guidelines, the authors carried out an extensive and current review regarding each statement present in the II Consensus, using the Medline/PubMed, Cochrane Library and SciELO databases with the following descriptors: gastric cancer, staging, endoscopic treatment and follow-up. In addition, each statement was classified according to the level of evidence and degree of recommendation.

RESULTS

Of the 24 statements, two (8.3%) were classified with level of evidence A, 11 (45.8%) with B and 11 (45.8%) with C. As for the degree of recommendation, six (25%) statements obtained grade of recommendation 1, nine (37.5%) recommendation 2a, six (25%) 2b and three (12.5%) grade 3.

CONCLUSION

The guidelines presented here are intended to assist professionals working in the fight against gastric cancer with relevant and current information, granting them to be applied in the daily medical practice.

Yield of staging laparoscopy in gastric cancer is influenced by Laurén histologic subtype

BACKGROUND

Staging laparoscopy (SL) with cytologic lavage is a useful staging procedure that allows tailoring the treatment of advanced gastric cancer (GC). The current study aimed to evaluate the total yield of SL in patients with various Laurén histo-types of GC, before planned neoadjuvant chemotherapy and gastrectomy.

METHODS

After exclusion of distant metastatic disease on imaging modalities, 173 patients with primary advanced gastric adenocarcinoma who underwent SL between August 2016 and September 2018, were eligible for the analysis. Patients sex, age, Lauren histo-type, tumor location, grade, cT, and cN were assessed in bivariate analysis. Multivariable logistic regression analysis was used to identify independent factors associated with peritoneal metastases.

RESULTS

Peritoneal metastases, ascites, and positive cytology were found in 39 (22.5%), 17 (9.8%) and 38 (22%) patients, respectively. The total yield of the SL in the current study was 36.4%. Multivariable logistic regression analysis revealed that serosal involvement (cT4) and diffuse histo-type were independent predictors of peritoneal metastases (OR, 15; 95% CI, 1.9-119, P = .02 and OR, 2.4; 95% CI, 1.2-4.6, P = .01, respectively).

CONCLUSIONS

Although cT4 and diffuse tumors show the highest association with peritoneal metastases, SL is a valuable diagnostic procedure in all advanced GC patients.

Gastric cancer and image-derived quantitative parameters: Part 2-a critical review of DCE-MRI and 18F-FDG PET/CT findings

Abstract

There is yet no consensus on the application of functional imaging and qualitative image interpretation in the management of gastric cancer. In this second part, we will discuss the role of image-derived quantitative parameters from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) in gastric cancer, as both techniques have been shown to be promising and useful tools in the clinical decision making of this disease. We will focus on different aspects including aggressiveness assessment, staging and Lauren type discrimination, prognosis prediction and response evaluation. Although both the number of articles and the patients enrolled in the studies were rather small, there is evidence that quantitative parameters from DCE-MRI such as K^trans, V_e, K_ep and AUC could be promising image-derived surrogate parameters for the management of gastric cancer. Data from ¹⁸F-FDG PET/CT studies showed that standardised uptake value (SUV) is significantly associated with the aggressiveness, treatment response and prognosis of this disease. Along with the results from diffusion-weighted MRI and contrast-enhanced multidetector computed tomography presented in Part 1 of this critical review, there are additional image-derived quantitative parameters from DCE-MRI and ¹⁸F-FDG PET/CT that hold promise as effective tools in the diagnostic pathway of gastric cancer.

Key Points

• Quantitative analysis from DCE-MRI and¹⁸F-FDG PET/CT allows the extrapolation of multiple image-derived parameters.

• Data from DCE-MRI (K^trans, V_e, K_ep and AUC) and ¹⁸F-FDG PET/CT (SUV) are non-invasive, quantitative image-derived parameters that hold promise in the evaluation of the aggressiveness, treatment response and prognosis of gastric cancer.