Association between glycemic status and the risk of gastric cancer in pre/peri-and postmenopausal women: A nationwide cohort study

PURPOSE

This study aimed to assess the correlation between glycemic status (prediabetes and type 2 diabetes mellitus) and the risk of gastric cancer according to menopausal status.

METHODS

A total of 982,559 pre/peri-menopausal and 1445,419 postmenopausal women aged ≥ 40, who underwent the Korean national health screening in 2009, were included and followed up until 2018. Hazard ratio (HR) and 95% confidence interval (CI) were calculated for development of gastric cancers according to hyperglycemic status in both groups using Cox proportional hazards models.

RESULTS

Over a mean follow-up period of 8.3 years, 3259 (0.33%) pre/peri-menopausal women and 13,245 (0.92%) postmenopausal women were diagnosed with gastric cancer. In postmenopausal women, only diabetes mellitus conferred a higher risk of gastric cancer compared to normal glycemic status (HR, 1.15; 95% CI, 1.09-1.20), with an increasing trend of gastric cancers from prediabetes to diabetes (P for trend < 0.001) observed regardless of menopausal status. Obesity, smoking, and heavy alcohol consumption was associated with increased gastric cancer risk mainly in the postmenopausal period.

CONCLUSIONS

The risk of gastric cancer escalates with deteriorating glycemic status in a dose-response manner. Diabetes mellitus is linked with an elevated risk of gastric cancer in postmenopausal women.

Staging laparoscopy with peritoneal lavage to identify peritoneal metastases and free intraperitoneal cancer cells in the management of locally advanced gastric cancer

INTRODUCTION

Gastric cancer often presents in advanced stage with a significant risk for peritoneal dissemination. Staging laparoscopy can be used to detect peritoneal carcinomatosis (PC+) and free cancer cells in peritoneal lavage cytology (CY+). The current study aimed to present the outcomes of staging laparoscopy and the prognosis of PC+ and CY+ in a Swedish high-volume center.

MATERIALS AND METHODS

A cohort study including all consecutive patients with locally advanced gastric cancer who underwent staging laparoscopy between February 2008 and October 2022. The laparoscopy findings were categorized as PC+, PC-CY+ (positive cytology without peritoneal carcinomatosis) or negative laparoscopy (PC-CY-). The primary endpoint was overall survival (OS) stratified by laparoscopy findings. The secondary endpoint was OS within each laparoscopy finding group stratified by subsequent treatment.

RESULTS

Among 168 patients who underwent staging laparoscopy, 78 patients (46%) had PC-CY-, 29 patients (17%) had PC-CY+ and 61 patients (36%) had PC+. Decreased OS was observed for both PC-CY+ patients (aHR 2.14, 95% CI 1.13-4.06) and PC+ patients (aHR 5.36, 95% CI 3.21-8.93), compared to PC-CY-. Patients with PC-CY+ who converted to PC-CY- after chemotherapy and underwent tumor resection seemed to have a better prognosis compared to patients with persisting PC-CY+.

CONCLUSIONS

Staging laparoscopy is an important tool in the staging of locally advanced gastric cancer. Tumor resection for patients with PC-CY+ who convert to PC-CY- may lead to improved survival for these patients.

Fewer Feedback Opportunities and Health Perception of Gastric Cancer Survivors: Opportunities for Patient Education

This study aimed to estimate the impact of having fewer opportunities for patient education on health perception of gastric cancer survivors by examining quality-of-life (QoL) responses from patients who had been away for chemotherapy for a year. The full-surveillance (FullSV) group was comprised of gastric cancer survivors with stage I cancer who completed preoperative and postoperative 3-, 6-, 9-, and 12-month surveillances. The returning (RTN) group was comprised of 1-year survivors of stage II cancer who had been away for chemotherapy for a year. Surveillance periods were utilized to provide patient education about expected postoperative weight changes. The European Organisation for Research and Treatment of Cancer QoL questionnaires were used to assess QoL. The study included a total of 278 patients (243 in the FullSV group and 35 in the RTN group). The baseline QoL was not significantly different between the groups. Significant differences in postoperative QoL were revealed by some scales (global health status/QoL, physical functioning, fatigue, financial difficulties, anxiety, dry mouth, and body image), all in favor of the FullSV group. Despite no significant difference in their actual weight changes, stronger weight dissatisfaction was revealed among the RTN group. Patients with fewer educational inputs for postoperative adjustment of weight perception were the ones with stronger dissatisfaction about current weight. The health perception of cancer survivors is under the constant influence of clinician feedback during patient education. For the best cancer survivorship care, sufficient opportunities for adjustment of health perception through patient education need to be ensured.

Neoadjuvant Chemotherapy Does Not Improve Survival in cT2N0M0 Gastric Adenocarcinoma Patients: A Multicenter Propensity Score Analysis

BACKGROUND

According to current international guidelines, stage cT2N0M0 gastric adenocarcinoma warrants preoperative chemotherapy followed by surgery. However, upfront surgery is often preferred in clinical practice, depending on patient clinical status and local treatment preferences.

OBJECTIVE

The aim of the present study was to assess the impact of neoadjuvant chemotherapy in overall survival (OS) and disease-free survival (DFS) of cT2N0M0 patients.

METHODS

A retrospective analysis was performed among 32 centers, including gastric adenocarcinoma patients operated between January 2007 and December 2017. Patients with cT2N0M0 stage were divided into upfront surgery (S) and neoadjuvant chemotherapy followed by surgery (CS) groups. Inverse probability of treatment weighting (IPTW) was used to compensate for baseline differences between the groups.

RESULTS

Among the 202 patients diagnosed with cT2N0M0 stage, 68 (33.7%) were in the CS group and 134 (66.3%) were in the S group. CS patients were younger (mean age 62.7 ± 12.8 vs. 69.8 ± 12.1 years for S patients; p < 0.001) and had a better health status (World Health Organization performance status = 0 in 60.3% of CS patients vs. 34.5% of S patients; p = 0.006). During follow-up, recurrence occurred in 27.2% and 19.6% of CS and S patients, respectively, after IPTW (p = 0.32). Five-year OS was similar between CS and S patients (78.9% vs. 68.3%; p = 0.42), as was 5-year DFS (70.4% vs. 68.5%; p = 0.96). Neoadjuvant chemotherapy was associated with neither OS nor DFS in multivariable analysis after IPTW.

CONCLUSIONS

Patients with cT2N0M0 gastric adenocarcinoma did not present a survival or recurrence benefit if treated with perioperative chemotherapy followed by surgery as opposed to surgery alone.

Value of orthogonal axial MR images in preoperative T staging of gastric cancer

PURPOSE

To assess the value of orthogonal axial images (OAI) of MRI in gastric cancer T staging.

METHODS

This retrospective study enrolled 133 patients (median age, 63 [range, 24-85] years) with gastric adenocarcinoma who underwent both CT and MRI followed by surgery. MRI lacking or incorporating OAI and CT images were evaluated, respectively. Diagnostic performance (accuracy, sensitivity, and specificity) for each T stage, overall diagnostic accuracy and rates of over- and understaging were quantified employing pathological T stage as a reference standard. The McNemar's test was performed to compare the overall accuracy.

RESULTS

Among patients with pT1-pT4 disease, MRI with OAI (accuracy: 88.7-94.7%, sensitivity: 66.7-93.0%, specificity: 91.5-100.0%) exhibited superior diagnostic performance compared to MRI without OAI (accuracy: 81.2-88.7%, sensitivity: 46.2-83.1%, specificity: 85.5-99.1%) and CT (accuracy: 88.0-92.5%, sensitivity: 53.3-90.1%, specificity: 88.7-98.1%). The overall accuracy of MRI with OAI was significantly higher (83.5%) than that of MRI without OAI (67.7%) (p < .001). However, there was no significant difference in the overall accuracy of MRI with OAI and CT (78.9%) (p = .35). The over- and understaging rates of MRI with OAI (12.0, 4.5%) were lower than those of MRI without OAI (21.8, 10.5%) and CT (12.8, 8.3%).

CONCLUSION

OAI play a pivotal role in the T staging of gastric cancer. MRI incorporating OAI demonstrated commendable performance for gastric cancer T-staging, with a slight tendency toward its superiority over CT.

Helicobacter pylori Infection Status and Gastric Tumor Incidence According to the Year of Birth

Background/Aims

: The prevalence of Helicobacter pylori-naive status is increasing. Nonetheless, biennial gastroscopy is recommended for all Koreans aged 40 to 75 years. This study aimed to determine whether gastric cancer screening guidelines could be changed according to H. pylori infection status and year of birth.

Methods

: Koreans who underwent serum assays and gastroscopy for gastric cancer screening between 2010 and 2016 were included if screening tests were followed up for ≥3 times. H. pylori infection was confirmed when invasive tests or 13C-urea breath tests were positive. In the case of negative test findings, eradication history, serologically detected atrophy, and intestinal metaplasia/atrophy were checked for past infection. If all were absent, H. pylori-naive status was confirmed.

Results

: Two-thousand and two (256 H. pylori-naive, 743 past-infected, and 1,003 infected) Koreans underwent screening tests for 95.5±28.4 months. The mean year of birth in the naive group (1969±7) differed from those of the past-infected (1957±10, p<0.001) and infected (1958±10, p<0.001) groups. H. pylori-naive status was correlated with recent year of birth (r=0.368, p<0.001). No gastric tumors were observed among the naive participants (p=0.007), whereas 23 adenomas, 18 adenocarcinomas, and two neuroendocrine tumors were detected in 1.9% (14/743) of past-infected and 2.5% (25/1,003) of infected participants, including four infected participants with metachronous tumors.

Conclusions

: The prevalence of H. pylori-naive status is increasing in young Koreans, and gastric tumors are rare in this population. Hence, biennial gastroscopy could be waived after the confirmation of naive status.

Advances in the study of gastric organoids as disease models

Gastric organoids are models created in the laboratory using stem cells and sophisticated three-dimensional cell culture techniques. These models have shown great promise in providing valuable insights into gastric physiology and advanced disease research. This review comprehensively summarizes and analyzes the research advances in culture methods and techniques for adult stem cells and induced pluripotent stem cell-derived organoids, and patient-derived organoids. The potential value of gastric organoids in studying the pathogenesis of stomach-related diseases and facilitating drug screening is initially discussed. The construction of gastric organoids involves several key steps, including cell extraction and culture, three-dimensional structure formation, and functional expression. Simulating the structure and function of the human stomach by disease modeling with gastric organoids provides a platform to study the mechanism of gastric cancer induction by Helicobacter pylori. In addition, in drug screening and development, gastric organoids can be used as a key tool to evaluate drug efficacy and toxicity in preclinical trials. They can also be used for precision medicine according to the specific conditions of patients with gastric cancer, to assess drug resistance, and to predict the possibility of adverse reactions. However, despite the impressive progress in the field of gastric organoids, there are still many unknowns that need to be addressed, especially in the field of regenerative medicine. Meanwhile, the reproducibility and consistency of organoid cultures are major challenges that must be overcome. These challenges have had a significant impact on the development of gastric organoids. Nonetheless, as technology continues to advance, we can foresee more comprehensive research in the construction of gastric organoids. Such research will provide better solutions for the treatment of stomach-related diseases and personalized medicine.

Preoperative Risk Stratification for Gastric Cancer: The Establishment of Dual-Energy CT-Based Radiomics Using Prospective Datasets at Two Centers

RATIONALE AND OBJECTIVES

To evaluate the performance of dual-energy CT (DECT)-based radiomics models for identifying high-risk histopathologic phenotypes-serosal invasion (pT4a), lymph node metastasis (LNM), lymphovascular invasion (LVI) and perineural invasion (PNI) in gastric cancer.

MATERIAL AND METHODS

This prospective bi-center study recruited histologically confirmed gastric adenocarcinoma patients who underwent triple-phase enhanced DECT before gastrectomy between January 2021 and July 2023. Radiomics features were extracted from polychromatic/monochromatic (40 keV, 100 keV)/iodine images at arterial/venous/delay phase, respectively. Predictive features were selected in the training dataset using logistic regression classifier, and trained models were applied to the external validation dataset. Performances of clinical models, conventional contrast enhanced CT (CECT) models and DECT models were evaluated using areas under the receiver operating characteristic curve (AUCs).

RESULTS

In total, 503 patients were recruited: 396 at training dataset (60.1 ± 10.8 years, 110 females, 286 males) and 107 at validation dataset (61.4 ± 9.5 years, 29 females, 78 males). DECT models dichotomizing pT4a, LNM, LVI, and PNI achieved AUCs of 0.891, 0.817, 0.834, and 0.889, respectively, in the validation dataset, similar with the CECT models. In the training dataset, compared to the CECT model, the DECT model provided increased performance for identifying pT4a, LNM, LVI (all P＜0.05), and similar performance for stratifying PNI (P = 0.104). The DECT models was associated with patient disease-free survival (all P＜0.05).

CONCLUSION

DECT radiomics can stratify patients preoperatively according to high-risk histopathologic phenotypes for gastric cancer and are associated with patient disease-free survival in the training dataset.

Dynamics of perioperative pancreatic exocrine function in patients undergoing reconstruction after gastrectomy for gastric cancer

BACKGROUND

Each method of reconstruction after gastrectomy results in a change in the digestive and absorptive status. However, there are few reports on the changes in pancreatic exocrine function after gastrectomy. We conducted this study to investigate the dynamics of pancreatic exocrine function after gastrectomy according to the method of reconstruction performed.

METHODS

The subjects of this study were 45 patients who underwent pancreatic exocrine function tests preoperatively and postoperatively, from among all patients who underwent gastrectomy for gastric cancer at our hospital between September, 2020 and March, 2022. We assessed pancreatic exocrine function using the Pancreatic Function Diagnostant (PFD) test.

RESULT

The mean preoperative PFD test result values for the distal gastrectomy (DG) Billroth I reconstruction (B-I) group and the DG Roux-en-Y reconstruction (R-Y) group were 62.6 and 67.3 (p = 0.36), respectively, and the mean postoperative PFD test result values for each group were 65.8 and 46.9 (p = 0.0094), respectively. A significant decrease in postoperative pancreatic function was observed in the DG R-Y group but not in the DG B-I group. The logistic regression analysis identified that age and the R-Y group were significantly correlated with a 10% decrease in the PFD value after gastrectomy.

CONCLUSIONS

Our study suggests that R-Y reconstruction may result in more impaired pancreatic exocrine function than B-I reconstruction.

Ferroptosis and its role in gastric and colorectal cancers

Ferroptosis is a novel mechanism of programmed cell death, characterized by intracellular iron overload, intensified lipid peroxidation, and abnormal accumulation of reactive oxygen species, which ultimately resulting in cell membrane impairment and demise. Research has revealed that cancer cells exhibit a greater demand for iron compared to normal cells, indicating a potential susceptibility of cancer cells to ferroptosis. Stomach and colorectal cancers are common gastrointestinal malignancies, and their elevated occurrence and mortality rates render them a global health concern. Despite significant advancements in medical treatments, certain unfavorable consequences and drug resistance persist. Consequently, directing attention towards the phenomenon of ferroptosis in gastric and colorectal cancers holds promise for enhancing therapeutic efficacy. This review aims to elucidate the intricate cellular metabolism associated with ferroptosis, encompassing lipid and amino acid metabolism, as well as iron metabolic processes. Furthermore, the significance of ferroptosis in the context of gastric and colorectal cancer is thoroughly examined and discussed.

Racial disparities of gastric cancer in the USA: an overview of epidemiology, global screening guidelines, and targeted screening in a heterogeneous population

Gastric cancer is the fifth most common cancer diagnosis and fourth leading cause of cancer-related death globally. The incidence of gastric cancer in the USA shows significant racial and ethnic disparities with gastric cancer incidence in Korean Americans being over five times higher than in non-Hispanic whites. Since gastric cancer is not common in the USA, there are no current screening guidelines. In countries with higher incidences of gastric cancer, screening guidelines have been implemented for early detection and intervention and this has been associated with a reduction in mortality. Immigrants from high incidence countries develop gastric cancer at lower rates once outside of their country of origin, but continue to be at higher risk for developing gastric cancer. This risk does seem to decrease with subsequent generations. With increasing availability of endoscopy, initiating gastric cancer screening guidelines for high-risk groups can have the potential to improve survival by diagnosing and treating gastric cancer at an earlier stage. This article aims to provide context to gastric cancer epidemiology globally, review risk factors for developing gastric cancer, highlight racial and ethnic disparities in gastric cancer burden in the USA, examine current guidelines that exist in high incidence countries, and suggest future studies examining the efficacy of additional screening in high-risk populations to reduce gastric cancer mortality and disparate burden on ethnic minorities in the USA.

Adjuvant and post-recurrent treatment patterns in patients with resectable gastric cancer in japan: a retrospective database cohort study

BACKGROUND

This study examined temporal shifts in adjuvant therapy patterns in Japanese patients with resectable gastric cancer (GC) and treatment patterns of first-line and subsequent therapy among those with recurrent disease.

METHODS

This retrospective analysis of hospital-based administrative claims data (April 1, 2008 to March 31, 2022) included adults (aged ≥ 20 years) with GC who started adjuvant therapy on or after October 1, 2008 (adjuvant cohort) and patients in the adjuvant cohort with disease recurrence (recurrent cohort), further defined by the time to recurrence (≤ 180 or > 180 days after adjuvant therapy).

RESULTS

In the adjuvant cohort (n = 17,062), the most common regimen during October 2008-May 2016 was tegafur/gimeracil/oteracil potassium (S-1; 95.7%). As new standard adjuvant regimen options were established, adjuvant S-1 use decreased to 65.0% and fluoropyrimidine plus oxaliplatin or docetaxel plus S-1 use increased to 15.0% and 20.0%, respectively, in September 2019-March 2022. In the recurrent cohort with no history of trastuzumab/trastuzumab deruxtecan treatment (n = 1257), the most common first-line regimens were paclitaxel plus ramucirumab (34.0%), capecitabine plus oxaliplatin (CapeOX; 17.0%), and nab-paclitaxel plus ramucirumab (10.1%) in patients with early recurrence, and S-1 plus oxaliplatin (26.3%), S-1 plus cisplatin (15.3%), CapeOX (14.0%), S-1 (13.2%), and paclitaxel plus ramucirumab (10.8%) in those with late recurrence.

CONCLUSIONS

This study demonstrated temporal shifts in adjuvant treatment patterns that followed the establishment of novel regimens, and confirmed that post-recurrent treatment patterns were consistent with the Japanese Gastric Cancer Association guideline recommendations.

Varlitinib and Paclitaxel for EGFR/HER2 Co-Expressing Advanced Gastric Cancer: a Multicenter Phase Ib/II Study (K-MASTER-13)

Purpose

Varlitinib is a pan-human epidermal growth (HER) inhibitor targeting epidermal growth factor receptor (EGFR), HER2, and HER4. We present a phase Ib/II study of a combination of varlitinib and weekly paclitaxel as a second-line treatment for patients with EGFR/HER2 co-expressing advanced gastric cancer (AGC).

Materials and Methods

Patients whose tumors with EGFR and HER2 overexpression by immunohistochemistry (IHC) (≥1+) were enrolled. Varlitinib and paclitaxel were investigated every 4 weeks. After determining the recommended phase II dose (RP2D) in phase Ib, a phase II study was conducted to evaluate the antitumor activity.

Results

RP2D was treated with a combination of varlitinib (300 mg twice daily) and paclitaxel. Among 27 patients treated with RP2D, the median PFS and overall survival (OS) were 3.3 months and 7.9 months, respectively, with a median follow-up of 15.7 months. Among 16 patients with measurable disease, the objective response rate (ORR) and disease control rate were 31% and 88%, respectively. Patients with strong HER2 expression (n=8) had a higher ORR and longer OS, whereas those with strong EGFR expression (n=3) had poorer outcomes. The most common adverse events (AEs) of any grade were neutropenia (52%), diarrhea (27%), AST/ALT elevation (22%), and nausea (19%). No treatment-related deaths or unexpected AEs resulting from treatment cessation were observed in patients with RP2D.

Conclusion

A combination of varlitinib and paclitaxel displayed manageable toxicity and modest antitumor activity in patients with EGFR/HER2 co-expressing AGC who progressed after first-line chemotherapy.

The Circular RNA Circ_0043947 Promoted Gastric Cancer Progression by Sponging miR-384 to Regulate CREB1 Expression

Background/Aims

: The occurrence and development of circular RNAs in gastric cancer (GC) has attracted increasing attention. This study focused on investigating the biological role and molecular mechanism of circ_0043947 in GC.

Methods

: The expression levels of circ_0043947, miR-384 and CAMP response element binding protein (CREB1) were determined by quantitative real-time polymerase chain reaction or Western blotting. Cell proliferation, migration, and invasion, the cell cycle and apoptosis were determined using a cell counting kit-8 assay, 5-ethynyl-2'-deoxyuridine assay, colony formation assay, wound healing assay, transwell assay, and flow cytometry assay. The interaction between miR-384 and circ_0043947 or CREB1 was verified by dual-luciferase reporter assay and RNA pull-down assay. The in vivo assay was conducted using a xenograft mouse model.

Results

: Circ_0043947 and CREB1 expression levels were significantly upregulated, whereas miR-384 expression levels were downregulated in GC tissues and cells. Functionally, knockdown of circ_0043947 inhibited cell proliferation, migration and invasion and induced G0/G1 phase arrest and apoptosis in vitro. Circ_0043947 could upregulate CREB1 expression by directly sponging miR-384. Rescue experiments showed that a miR-384 inhibitor significantly reversed the inhibitory effect of si-circ_0043947 on GC progression, and CREB1 overexpression significantly reversed the inhibitory effect of miR-384 mimics on the progression of GC cells. Furthermore, silencing of circ_0043947 inhibited tumor growth in vivo.

Conclusions

: Circ_0043947 acted as an oncogenic factor in GC to mediate GC cell proliferation, migration, and invasion, the cell cycle and apoptosis by regulating the miR-384/CREB1 axis. Circ_0043947 may be a potential target for GC diagnosis and therapy.

Effector Function Characteristics of Exhausted CD8+ T-cell in Microsatellite Stable and Unstable Gastric Cancer

Purpose

Gastric cancer exhibits molecular heterogeneity, with the microsatellite instability high (MSI-H) subtype drawing attention for its distinct features. Despite a higher survival rate, MSI-H gastric cancer lack significant benefits from conventional chemotherapy. The immune checkpoint inhibitors (ICIs), presents a potential avenue, but a deeper understanding of the tumor immune microenvironment of MSI-H gastric cancer is essential.

Materials and Methods

We explored the molecular characteristics of CD8+ T cell subtypes in three MSI-H and three microsatellite stable (MSS) gastric cancer samples using single-cell RNA sequencing and spatial transcriptome analysis.

Results

In MSI-H gastric cancer, significantly higher proportions of effector memory T cell (Tem), exhausted T cell (Tex), proliferative exhausted T cell (pTex), and proliferative T cell were observed, while MSS gastric cancer exhibited significantly higher proportions of mucosal-associated invariant T (MAIT) cell and NKT cell. In MSI-H gastric cancer, Tex and pTex exhibited a significant upregulation of the exhaustion marker LAG3, as well as elevated expression of effector function markers such as IFNG, GZMB, GZMH, and GZMK, compared to those in MSS gastric cancer. The IFN-γ signaling pathway of Tex and pTex was retained compared to those of MSS gastric cancer. The spatial transcriptome analysis demonstrates the IFN-γ signaling pathway between neighboring Tex and malignant cell, showcasing a significantly elevated interaction in MSI-H gastric cancer.

Conclusion

Our study reveals novel finding indicating that IFN-γ signaling pathway is retained in Tex and pTex of MSI-H gastric cancer, offering a comprehensive perspective for future investigations into immunotherapy for gastric cancer.

NESC Multicenter Phase II Trial in the Preoperative Treatment of Gastric Adenocarcinoma with Chemotherapy (Docetaxel-Cisplatin-5FU+Lenograstim) Followed by Chemoradiation Based 5FU and Oxaliplatin and Surgery

PURPOSE

Preoperative chemoradiation (CRT) is expected to increase the rate of curative resection and complete histological response. In this trial, we investigated the efficacy of a neoadjuvant CRT regimen in gastric adenocarcinoma (NCT01565109 trial).

MATERIALS AND METHODS

Patients with stage IB to IIIC gastric adenocarcinoma, endoscopy ultrasound and computed tomography-scan diagnosed, were eligible for this phase II trial. Neoadjuvant treatment consisted of 2 cycles of chemotherapy with DCF (docetaxel, cisplatin, and 5-fluorouracil [5FU]) followed by preoperative CRT with oxaliplatin, continuous 5FU and radiotherapy (45 Gy in 25 fractions of 1.8 Gy, 5 fractions per week for 5 weeks) administered before surgery. R0-resection rate, pathological complete response (pathCR) rate, and survival (progression-free survival [PFS] and overall survival [OS]) were evaluated as primary endpoints.

RESULTS

Among 33 patients included, 32 patients (97%) received CRT and 26 (78.8%) were resected (R0 resection for all patients resected). Among resected patients, we report pathCR in 23,1% and pathologic major response (tumor regression grade 2 according to Mandard's classification) in 26,9%. With a median follow-up duration of 5.82 years (range, 0.4 to 9.24 years), the estimated median OS for all 33 patients was not reached; 1-, 3-, and 5-year OS rates were 85%, 61%, and 52%, respectively. Among resected patients, those whose histological response was tumor grade regression (TRG) 1-2 had significantly better OS and PFS rates than those with a TRG 3-4-5 response (p=0.019 and p=0.016, respectively).

CONCLUSION

Promising results from trials involving preoperative chemoradiation followed by surgery in gastric cancer need to be further evaluated in a phase III trial.

A Modified eCura System to Stratify the Risk of Lymph Node Metastasis in Undifferentiated-Type Early Gastric Cancer After Endoscopic Resection

PURPOSE

The original eCura system was designed to stratify the risk of lymph node metastasis (LNM) after endoscopic resection (ER) in patients with early gastric cancer (EGC). We assessed the effectiveness of a modified eCura system for reflecting the characteristics of undifferentiated-type (UD)-EGC.

MATERIALS AND METHODS

Six hundred thirty-four patients who underwent non-curative ER for UD-EGC and received either additional surgery (radical surgery group; n=270) or no further treatment (no additional treatment group; n=364) from 18 institutions between 2005 and 2015 were retrospectively included in this study. The eCuraU system assigned 1 point each for tumors >20 mm in size, ulceration, positive vertical margin, and submucosal invasion <500 µm; 2 points for submucosal invasion ≥500 µm; and 3 points for lymphovascular invasion.

RESULTS

LNM rates in the radical surgery group were 1.1%, 5.4%, and 13.3% for the low- (0-1 point), intermediate- (2-3 points), and high-risk (4-8 points), respectively (P-for-trend<0.001). The eCuraU system showed a significantly higher probability of identifying patients with LNM as high-risk than the eCura system (66.7% vs. 22.2%; McNemar P<0.001). In the no additional treatment group, overall survival (93.4%, 87.2%, and 67.6% at 5 years) and cancer-specific survival (99.6%, 98.9%, and 92.9% at 5 years) differed significantly among the low-, intermediate-, and high-risk categories, respectively (both P<0.001). In the high-risk category, surgery outperformed no treatment in terms of overall mortality (hazard ratio, 3.26; P=0.015).

CONCLUSIONS

The eCuraU system stratified the risk of LNM in patients with UD-EGC after ER. It is strongly recommended that high-risk patients undergo additional surgery.

Safety and efficacy of apatinib in combination with chemotherapy with or without immunotherapy versus chemotherapy alone as first-line treatment for advanced gastric cancer

The specific first-line regimen for advanced gastric cancer (GC) is still controversial. The benefit of apatinib for first-line treatment of advanced GC remains unknown and needs to be further explored. Eighty-two patients with advanced GC treated in our institution from October 2017 to March 2023 were retrospectively reviewed. All individuals had her-2 negative GC and had received at least two cycles of first-line treatment, including 44 patients in the combination treatment group (apatinib in combination with chemotherapy with or without immunotherapy) and 38 patients in the simple chemotherapy group. We evaluated the efficacy and safety of apatinib in combination with chemotherapy with or without immunotherapy in the first-line treatment of advanced GC by comparing the efficacy, progression-free survival (PFS), and adverse events in two groups of patients. The median PFS of the simple chemotherapy group was 9.25 months (95% confidence interval (CI), 6.1-11.2 months), and that of the combination treatment group was 10.9 months (95% CI, 7.9-15.8 months), which was 1.65 months longer than the simple chemotherapy group. Statistically significant differences are shown (P = 0.022). The objective response rate (ORR) of the combination treatment group was 65.9%, and 36.8% in the simple chemotherapy group. Statistically significant differences are shown (P = 0.014). No serious (Grade IV) adverse events occurred in either group. Our study indicates that apatinib in combination with chemotherapy with or without immunotherapy as first-line treatment for advanced GC exhibits good anti-tumor activity and is well tolerated by patients.

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.

Comparison of totally laparoscopic and laparoscopic-assisted approach in gastrectomy with D2 lymphadenectomy for advanced gastric cancer after neoadjuvant chemotherapy: a retrospective comparative study

Purpose

Neoadjuvant chemotherapy is strongly recommended for advanced gastric cancer due to good local control and a high rate of R0 dissection with this strategy. Minimally invasive techniques such as laparoscopy-assisted or total laparoscopic approaches is becoming more and more acceptable in the treatment for gastric cancer. However, the safety and efficiency of total laparoscopic D2 gastrectomy (TLG) for advanced gastric cancer after neoadjuvant chemotherapy have not been well evaluated.

Methods

A retrospective study in a single center from 2014 to 2016 was conducted. A total of 65 locally advanced gastric cancers were treated by laparoscopy-assisted gastrectomy (LAG) or TLG. Parameters which include operation time, blood loss, complications, hospital stay, 3-year overall survival, and 3-year disease-free survival were used for comparison.

Results

The time of operation in the TLG group was shorter than in the LAG group (P = 0.013), blood loss was less (P = 0.002) and time to first flatus was shorter (P = 0.039) in the TLG group than that in the LLG group. Intraoperative and postoperative complications were comparable in both groups. No significant difference was found in 3-year overall and disease-free survival.

Conclusion

For patients with locally advanced gastric cancer after neoadjuvant chemotherapy, laparoscopic D2 gastrectomy can be considered as a safe and efficient alternative. A further multicenter prospective randomized controlled study is needed to elucidate the applicability of this technique for advanced gastric cancer.

Predicting pathologic response to neoadjuvant chemotherapy in locally advanced gastric cancer: The establishment of a spectral CT-based nomogram from prospective datasets

BACKGROUND

To establish a spectral CT-based nomogram for predicting early neoadjuvant chemotherapy (NAC) response for locally advanced gastric cancer (LAGC).

METHODS

This study prospectively recruited 222 cases (177 male and 45 female patients, 9.59 ± 9.54 years) receiving NAC and radical gastrectomy. Triple enhanced spectral CT scans were performed before NAC initiation. According to post-operative tumor regression grade (TRG), patients were classified into responders (TRG = 0 + 1) or non-responders (TRG = 2 + 3), and split into a primary (156) and validation (66) dataset at 7:3 ratio chronologically. We compared clinicopathological data, follow-up information, iodine concentration (IC), normalized ICs (nICs) in arterial/venous/delayed phases (AP/VP/DP) between responders and non-responders. Independent risk factors of response were screened by multivariable logistic regression and adopted for model construction. Model was visualized by nomograms and its capability was determined through receiver operating characteristic (ROC) curves. Log-rank survival analysis was conducted to explore associations between TRG, nomogram and patients' survival.

RESULTS

This work identified Borrmann classification, ICDP, and nICDP were independent risk factors of response outcomes. A spectral CT-based nomogram was built accordingly and achieved an area under the curve (AUC) of 0.797 (0.692-0.879) and 0.741(0.661-0.811) for the primary and validation dataset, respectively, higher than AUC of individual parameters alone. The nomogram was related to disease-free survival in the validation dataset (Hazard ratio (HR): 5.19 [1.18-12.93], P = 0.02).

CONCLUSIONS

The spectral CT-based nomogram provides an efficient tool for predicting the pathologic response outcomes of GC after NAC and disease-free survival risk stratification.

Clinicopathological and endoscopic features of Helicobacter pylori infection-negative gastric cancer in Japan: a retrospective study

Background/Aims

Helicobacter pylori infection-negative gastric cancer (HPNGC) has not been systematically investigated in consecutive patients. Hence, this study aimed to investigate the clinicopathological and endoscopic features of HPNGC.

Methods

This single-center retrospective study selected participants from patients with gastric cancer who were treated at the Fukuoka University Chikushi Hospital between January 2013 and December 2021. Only patients diagnosed with HPNGC were enrolled, and their clinicopathological and endoscopic features were analyzed in detail.

Results

The prevalence of HPNGC in the present study was 2.6% (54/2112). The types of HPNGC observed in each gastric region were as follows: advanced gastric cancer was observed in the cardia; gastric adenocarcinoma of fundic-gland differentiation, gastric adenocarcinoma of foveolar-type presenting with whitish elevation and raspberry-like foveolar-type gastric adenocarcinoma, gastric adenocarcinoma arising in polyposis, and gastric adenocarcinoma with autoimmune gastritis were observed in the fundic gland region ranging from the gastric fornix to the gastric body; signet-ring cell carcinoma was observed in the gastric-pyloric transition region ranging from the lower gastric body to the gastric angle; and well-differentiated tubular adenocarcinoma with low-grade atypia was observed in the antrum.

Conclusions

This study revealed that tumors from each gastric region exhibited distinct macroscopic and histological types in HPNGC.

Combined DNA Methylation and Gastric Microbiome Marker Predicts Helicobacter pylori-Negative Gastric Cancer

Background/Aims

While DNA methylation and gastric microbiome are each associated with gastric cancer (GC), their combined role in predicting GC remains unclear. This study investigated the potential of a combined DNA methylation and gastric microbiome signature to predict Helicobacter pylori-negative GC.

Methods

In this case-control study, we conducted quantitative methylation-specific polymerase chain reaction to measure the methylation levels of DKK3, SFRP1, EMX1, NKX6-1, MIR124-3, and TWIST1 in the gastric mucosa from 75 H. pylori-negative patients, including chronic gastritis (CG), intestinal metaplasia (IM), and GC. A combined analysis of DNA methylation and gastric microbiome, using 16S rRNA gene sequencing, was performed in 30 of 75 patients.

Results

The methylation levels of DKK3, SFRP1, EMX1, MIR124-3, and TWIST1 were significantly higher in patients with GC than in controls (all q<0.05). MIR124-3 and TWIST1 methylation levels were higher in patients with IM than those with CG and also in those with GC than in those with IM (all q<0.05). A higher methylation level of TWIST1 was an independent predictor for H. pylori-negative GC after adjusting for age, sex, and atrophy (odds ratio [OR], 15.15; 95% confidence interval [CI], 1.58 to 145.46; p=0.018). The combination of TWIST1 methylation and GC microbiome index (a microbiome marker) was significantly associated with H. pylori-negative GC after adjusting for age, sex, and atrophy (OR, 50.00; 95% CI, 1.69 to 1,476; p=0.024).

Conclusions

The combination of TWIST1 methylation and GC microbiome index may offer potential as a biomarker for predicting H. pylori-negative GC.

Assessment of programmed death-ligand 1 expression in primary tumors and paired lymph node metastases of gastric adenocarcinoma

BACKGROUND

Anti-programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) immunotherapy has demonstrated promising results on gastric cancer (GC). However, PD-L1 can express differently between metastatic sites and primary tumors (PT).

AIM

To compare PD-L1 status in PT and matched lymph node metastases (LNM) of GC patients and to determine the correlation between the PD-L1 status and clinicopathological characteristics.

METHODS

We retrospectively reviewed 284 GC patients who underwent D2-gastrectomy. PD-L1 was evaluated by immunohistochemistry (clone SP142) using the combined positive score. All PD-L1+ PT staged as pN+ were also tested for PD-L1 expression in their LNM. PD-L1(-) GC with pN+ served as the comparison group.

RESULTS

Among 284 GC patients included, 45 had PD-L1+ PT and 24 of them had pN+. For comparison, 44 PD-L1(-) cases with pN+ were included (sample loss of 4 cases). Of the PD-L1+ PT, 54.2% (13/24 cases) were also PD-L1+ in the LNM. Regarding PD-L1(-) PT, 9.1% (4/44) had PD-L1+ in the LNM. The agreement between PT and LNM had a kappa value of 0.483. Larger tumor size and moderate/severe peritumoral inflammatory response were associated with PD-L1 positivity in both sites. There was no statistical difference in overall survival for PT and LNM according to the PD-L1 status (P = 0.166 and P = 0.837, respectively).

CONCLUSION

Intra-patient heterogeneity in PD-L1 expression was observed between the PT and matched LNM. This disagreement in PD-L1 status may emphasize the importance of considering different tumor sites for analyses to select patients for immunotherapy.

Analysis of Characteristics and Risk Factors of Patients with Single Gastric Cancer and Synchronous Multiple Gastric Cancer among 14,603 Patients

Background/Aims

Synchronous multiple gastric cancer (SMGC) accounts for approximately 6% to 14% of gastric cancer (GC) cases. This study aimed to identify risk factors for SMGC.

Methods

A total of 14,603 patients diagnosed with GC were prospectively enrolled. Data including age, sex, body mass index, smoking, alcohol consumption, family history, p53 expression, microsatellite instability, cancer classification, lymph node metastasis, and treatment were collected. Risk factors were analyzed using logistic regression analysis between a single GC and SMGC.

Results

The incidence of SMGC was 4.04%, and that of early GC (EGC) and advanced GC (AGC) was 5.43% and 3.11%, respectively. Patients with SMGC were older (65.33 years vs 61.75 years, p<0.001) and more likely to be male. Lymph node metastasis was found in 27% of patients with SMGC and 32% of patients with single GC. Multivariate analysis showed that SMGC was associated with sex (male odds ratio [OR], 1.669; 95% confidence interval [CI], 1.223 to 2.278; p=0.001), age (≥65 years OR, 1.532; 95% CI, 1.169 to 2.008; p=0.002), and EGC (OR, 1.929; 95% CI, 1.432 to 2.600; p<0.001). Survival rates were affected by Lauren classification, sex, tumor size, cancer type, distant metastasis, and venous invasion but were not related to the number of GCs. However, the survival rate of AGC with SMGC was very high.

Conclusions

SMGC had unique characteristics such as male sex, older age, and EGC, and the survival rate of AGC, in which the intestinal type was much more frequent, was very good (Trial registration number: NCT04973631).

The Impact of Sedation on Cardio-Cerebrovascular Adverse Events after Surveillance Esophagogastroduodenoscopy in Patients with Gastric Cancer: A Nationwide Population-Based Cohort Study

Background/Aims

The impact of sedation on cardio-cerebrovascular (CCV) adverse events after esophagogastroduodenoscopy (EGD) in patients with gastric cancer (GC) is unclear. We investigated the incidence rate and impact of sedation on CCV adverse events after surveillance EGD in patients with GC.

Methods

We performed a nationwide population-based cohort study using the Health Insurance Review and Assessment Service databases from January 1, 2018, to December 31, 2020. Using a propensity score-matched analysis, patients with GC were divided into two groups: sedative agent users and nonusers for surveillance EGD. We compared the occurrence of CCV adverse events within 14 days between the two groups.

Results

Of the 103,463 patients with GC, newly diagnosed CCV adverse events occurred in 2.57% of patients within 14 days after surveillance EGD. Sedative agents were used in 41.3% of the patients during EGD. The incidence rates of CCV adverse events with and without sedation were 173.6/10,000 and 315.4/10,000, respectively. Between sedative agent users and nonusers based on propensity score matching (28,008 pairs), there were no significant differences in the occurrence of 14-day CCV, cardiac, cerebral, and other vascular adverse events (2.28% vs 2.22%, p=0.69; 1.44% vs 1.31%, p=0.23; 0.74% vs 0.84%, p=0.20; 0.10% vs 0.07%, p=0.25, respectively).

Conclusions

Sedation during surveillance EGD was not associated with CCV adverse events in patients with GC. Therefore, the use of sedative agents may be considered in patients with GC during surveillance EGD without excessive concerns about CCV adverse events.

Endoscopic Features of Undifferentiated-Type Early Gastric Cancer in Patients with Helicobacter pylori-Uninfected or -Eradicated Stomachs: A Comprehensive Review

Since the indications for endoscopic submucosal dissection have been expanded to include undifferentiated-type early gastric cancers, improvements in preoperative diagnostic ability have been an area of research. There are also concerns about the impact on the diagnosis of Helicobacter pylori infection. Based on our previous studies, in undifferentiated-type early gastric cancers, magnifying endoscopy with narrow-band imaging is useful for delineating the demarcation regardless of the tumor size. Additionally, inflammatory cell infiltration appears to be a cause of misdiagnosis, suggesting that the resolution of inflammation could contribute to the accurate diagnosis of demarcations. As such, the accuracy of demarcation in eradicated and uninfected cases is higher than that in non-eradicated cases. The common features of the endoscopic findings were discoloration under white-light imaging and a predominance of sites in the lower and middle regions. The uninfected group was characterized by smaller tumor size, flat type, more extended intervening parts in magnifying endoscopy with narrow-band imaging, and pure signet ring cell carcinoma. In contrast, the eradication and non-eradication groups were characterized by larger tumor size, depressed type, and wavy microvessels in magnifying endoscopy with narrow-band imaging. In this comprehensive review, as described above, we discuss the diagnosis of demarcation of undifferentiated-type early gastric cancers, undifferentiated-type early gastric cancers that developed following H. pylori eradication, and H. pylori-uninfected undifferentiated-type early gastric cancers, with a focus on studies with self-examination and endoscopic findings and describe the future direction.

Twenty-four-month Progression-free Survival in HER2-amplified Advanced Gastric Cancer with Brain Metastases after Trastuzumab Deruxtecan Treatment: A Case Report and Literature Review

BACKGROUND

Trastuzumab deruxtecan (T-DXd) has shown promising outcomes as a second or subsequent-line treatment for human epidermal growth factor-2 (HER2)-positive advanced gastric or gastroesophageal junction cancer.

CASE PRESENTATION

We reported a 49-year-old male patient with stage IV HER2-amplified gastric cancer. Despite extensive pretreatments, including first-line trastuzumab plus FOLFOX, second-- line trastuzumab plus FOLFOX, followed by traditional Chinese medicine, third-line nivolumab plus trastuzumab, fourth-line pyrotinib plus paclitaxel and five hepatic arterial chemoembolization procedures, and fifth-line pembrolizumab plus nab-paclitaxel and thoracic radiotherapy, the patient experienced disease progression. In April 2021, T-DXd was initiated as the sixth-line therapy in combination with radiotherapy for brain metastases. After one treatment cycle, the patient achieved a partial response. T-DXd was discontinued in August 2022 due to recurrent anemia attributed to cardiac stenosis-related bleeding.

CONCLUSION

The condition of the patient remained stable until May 2023, indicating a progression-free survival of over 24 months. This case suggests that T-DXd may offer long-term clinical benefits in patients with HER2-amplified advanced gastric cancer with brain metastases.

Modeling Epidemiology Data with Machine Learning Technique to Detect Risk Factors for Gastric Cancer

PURPOSE

Gastric cancer (GC) ranks as the 7th most common cancer worldwide and a leading cause of cancer mortality. In Iran, stomach malignancies are the most common fatal cancers with higher than world average incidence. In recent years, methods like machine learning that provide the opportunity of merging health issues with computational power and learning capacity have caught considerable attention for prediction and diagnosis of diseases. In this study, we aimed to model GC data to find risk factors and identify GC cases in Golestan Cohort Study (GCS), using gradient boosting as a machine learning technique.

METHODS

Since the GC class (280) was smaller than not-GC (49,467), "Synthetic Minority Oversampling Technique" was used to balance the dataset. Seventy percent of the data was used to train the gradient boosting algorithm and find effective factors on gastric cancer, and the remaining 30% was used for accuracy assessment.

RESULTS

Our results indicated that out of 19 factors, age, social economical status, tea temperature, body mass index, gender, and education were the top six effective factors with impact rates of 0.24, 0.16, 0.13, 0.13, and 0.07, respectively. The trained model classified 70 out of 72 GC patients in the test set, correctly.

CONCLUSION

The results indicate that this model can effectively detect gastric cancer (GC) by utilizing important risk factors, thus avoiding the need for invasive procedures. The model's performance is reliable when provided with an adequate amount of input data, and as the dataset expands, its accuracy and generalization improve significantly. Overall, the trained system's success stems from its ability to identify risk factors and identify cancer patients.

Rivoceranib, a VEGFR-2 inhibitor, monotherapy in previously treated patients with advanced or metastatic gastric or gastroesophageal junction cancer (ANGEL study): an international, randomized, placebo-controlled, phase 3 trial

BACKGROUND

Rivoceranib is an oral, selective tyrosine kinase inhibitor of vascular endothelial growth factor receptor-2. ANGEL (NCT03042611) was a global, randomized, double-blinded, placebo-controlled, phase 3 study evaluating rivoceranib as 3rd-line or ≥4th-line therapy in patients with advanced/metastatic gastric or gastroesophageal junction (GEJ) cancer.

METHODS

Patients had failed ≥2 lines of chemotherapy and were randomized 2:1 to rivoceranib 700 mg once daily or placebo with best supportive care.

PRIMARY ENDPOINT

overall survival (OS) in the intention-to-treat population. Secondary endpoints: progression-free survival (PFS), objective response rate (ORR), and disease control rate (DCR) by blinded independent central review (BICR).

RESULTS

In total, 460 patients (rivoceranib n = 308, placebo n = 152) were enrolled. OS was not statistically different for rivoceranib versus placebo (median 5.78 vs. 5.13 months; hazard ratio [HR] 0.93, 95% CI 0.74-1.15; p = 0.4724). PFS by BICR (median 2.83 vs. 1.77 months; HR 0.58, 95% CI 0.47-0.71; p < 0.0001), ORR (6.5% vs. 1.3%; p = 0.0119), and DCR (40.3 vs. 13.2%; p < 0.0001) were improved with rivoceranib versus placebo. In patients receiving ≥4th-line therapy, OS (median 6.34 vs. 4.73 months; p = 0.0192) and PFS by BICR (median 3.52 vs. 1.71 months; p < 0.0001) were improved with rivoceranib versus placebo. The most common grade ≥ 3 treatment-emergent adverse events with rivoceranib were hypertension (17.9%), anemia (10.4%), aspartate aminotransferase increased (9.4%), asthenia (8.5%), and proteinuria (7.5%).

CONCLUSIONS

This study did not meet its primary OS endpoint. Compared to placebo, rivoceranib improved PFS, ORR, and DCR. Rivoceranib also improved OS in a prespecified patient subgroup receiving ≥4th-line therapy.

Risk of tuberculosis after endoscopic resection and gastrectomy in gastric cancer: nationwide population-based matched cohort study

BACKGROUND

This study aimed to investigate the association between gastrectomy and endoscopic resection for gastric cancer and the subsequent tuberculosis incidence.

METHODS

We conducted a nationwide matched cohort study using data from the Korea National Health Insurance Service from 2013 to 2019. We created two cohorts: patients who underwent gastrectomy and those who had endoscopic resection. Each patient was matched 1:1 with an unexposed individual based on index year, age, sex, income, and various comorbidities. The primary outcome was the incidence of tuberculosis during the follow-up period.

RESULTS

Our study comprised 90,886 gastrectomy patients and 46,759 endoscopic resection patients. The tuberculosis incidence was significantly higher in the gastrectomy group compared to its matched non-gastrectomy group (IRR 1.69, 95% CI 1.43-1.99, p < .001). In contrast, there was no significant difference in tuberculosis incidence between the endoscopic resection group and its matched non-resection group (IRR 0.95, 95% CI 0.75-1.19, p = 0.627). The Kaplan-Meier cumulative incidence also did not differ between the two groups. However, tuberculosis incidence significantly increased in the first year after endoscopic resection.

CONCLUSION

Gastrectomy for gastric cancer is associated with a higher incidence of subsequent tuberculosis, while no significant association was observed for endoscopic resection. However, tuberculosis incidence increases significantly during the first year after endoscopic resection.

Risk factors for abdominal surgical infectious complications after distal gastrectomy for gastric cancer: A post-hoc analysis of a randomized controlled trial (JCOG0912)

BACKGROUND

Abdominal surgical infectious complications (ASIC) after gastrectomy for gastric cancer impair patients' survival and quality of life. JCOG0912 was conducted to compare laparoscopy-assisted distal gastrectomy with open distal gastrectomy for clinical stage IA or IB gastric cancer. The present study aimed to identify risk factors for ASIC using prospectively collected data.

METHODS

We performed a post-hoc analysis of the risk factors for ASIC using the dataset from JCOG0912. All complications were evaluated according to the Clavien-Dindo classification (CD). ASIC was defined as CD grade I or higher anastomotic leakage, pancreatic fistula, abdominal abscess, and wound infection. Analyses were performed using the logistic regression model for univariable and multivariable analyses.

RESULTS

A total of 910 patients were included (median age, 63 years; male sex, 61 %). Among them, ASIC occurred in 5.8 % of patients. In the univariable analysis, male sex (odds ratio [OR] 2.855, P = 0.003), diabetes (OR 2.565, P = 0.029), and Roux-en-Y (R-Y) reconstruction (vs. Billroth Ⅰ, OR 2.707, P = 0.002) were significant risk factors for ASIC. In the multivariable analysis, male sex (OR 2.364, P = 0.028) and R-Y reconstruction (vs. Billroth Ⅰ, OR 2.310, P = 0.015) were independent risk factors for ASIC.

CONCLUSIONS

Male sex and R-Y reconstruction were risk factors for ASIC after distal gastrectomy. Therefore, when performing surgery on male patients or when R-Y reconstruction is selected after gastrectomy for gastric cancer, surgeons should pay special attention to prevent ASIC.

Daily Diet and Nutrition Risk Factors for Gastric Cancer Incidence in a Japanese Population

Background/Aims

: Nutritional factors associated with gastric cancer (GC) are not completely understood. We aimed to determine the effect of nutrient intake on the incidence of GC.

Methods

: This was a post hoc analysis of a prospective trial that evaluated modalities for GC screening in participants aged 30 to 74 years living in high-risk areas for GC in Japan between June 2011 and March 2013. The patients were followed up for GC incidence for 6 years. All participants completed a self-administered food frequency questionnaire (FFQ) upon enrollment before GC screening. Daily nutrient intake was calculated from the FFQ and dichotomized at each cutoff value using receiver operating characteristic analysis. Risk factors associated with GC incidence were investigated in terms of nutrient intake and participant characteristics using Cox proportional hazards regression analysis.

Results

: Overall, 1,147 participants were included in this analysis. The median age was 62 years, and 50.7% of the participants were men. The median follow-up period was 2,184 days. GC was detected in 25 participants during the follow-up. Multivariate Cox proportional hazards regression analysis revealed that the intake of sodium (adjusted hazards ratio [aHR], 3.905; 95% confidence interval [CI], 1.520 to 10.035; p=0.005) and vitamin D (aHR, 2.747; 95% CI, 1.111 to 6.788, p=0.029) were positively associated with GC incidence, whereas the intake of soluble dietary fiber (aHR, 0.104; 95% CI, 0.012 to 0.905; p=0.040) was inversely associated with GC incidence.

Conclusions

: Daily high intake of sodium and vitamin D and low soluble dietary fiber intake are associated with GC incidence.

Retrograde drainage for duodenal stump leakage using ileal decompression tube guided by double-balloon endoscopy: a novel case report

BACKGROUND

Duodenal stump leakage is a serious post-gastrectomy complication, and there have been no reports on endoscopic drainage.

CASE PRESENTATION

We report a case of duodenal stump leakage after laparoscopic gastrectomy with Roux-en-Y reconstruction in a 68-year-old man. First-line conservative management was ineffective. Reoperation was performed because of severe abdominal pain and increased ascites. After reoperation, duodenal stump leakage recurred with bleeding from the anterior superior pancreaticoduodenal artery. Coil embolization and pigtail catheter insertion were performed. Furthermore, we retrogradely inserted an ileal tube for tube decompression near the duodenal stump using double-balloon endoscopy for effective drainage. After tube insertion, duodenal stump leakage decreased; on the 47th primary postoperative day, the patient was discharged. The primary postoperative course was uneventful after 1 year and 9 months of follow-up.

CONCLUSIONS

This is the first successful case of duodenal stump leakage treated with retrograde decompression tube insertion near the duodenal stump using double-balloon endoscopy.

Modern insights into the pathophysiology and treatment of pseudoachalasia

BACKGROUND

Secondary achalasia or pseudoachalasia is a clinical presentation undistinguishable from achalasia in terms of symptoms, manometric, and radiographic findings, but associated with different and identifiable underlying causes.

METHODS

A literature review was conducted on the PubMed database restricting results to the English language. Key terms used were "achalasia-like" with 63 results, "secondary achalasia" with 69 results, and "pseudoachalasia" with 141 results. References of the retrieved papers were also manually reviewed.

RESULTS

Etiology, diagnosis, and treatment were reviewed.

CONCLUSIONS

Pseudoachalasia is a rare disease. Most available evidence regarding this condition is based on case reports or small retrospective series. There are different causes but all culminating in outflow obstruction. Clinical presentation and image and functional tests overlap with primary achalasia or are inaccurate, thus the identification of secondary achalasia can be delayed. Inadequate diagnosis leads to futile therapies and could worsen prognosis, especially in neoplastic disease. Routine screening is not justifiable; good clinical judgment still remains the best tool. Therapy should be aimed at etiology. Even though Heller's myotomy brings the best results in non-malignant cases, good clinical judgment still remains the best tool as well.

Safety and feasibility of minimally invasive gastrectomy following preoperative chemotherapy for highly advanced gastric cancer

BACKGROUND

This study aimed to determine the safety and feasibility of minimally invasive gastrectomy in patients who underwent preoperative chemotherapy for highly advanced gastric cancer.

METHODS

Preoperative chemotherapy was indicated for patients with advanced large tumors (≥ cT3 and ≥ 5 cm) and/or bulky node metastasis (≥ 3 cm × 1 or ≥ 1.5 cm × 2). Between January 2009 and March 2022, 150 patients underwent preoperative chemotherapy followed by gastrectomy with R0 resection, including conversion surgery (robotic, 62; laparoscopic, 88). The outcomes of these patients were retrospectively examined.

RESULTS

Among them, 41 and 47 patients had stage IV disease and underwent splenectomy, respectively. Regarding operative outcomes, operative time was 475 min, blood loss was 72 g, morbidity (grade ≥ 3a) rate was 12%, local complication rate was 10.7%, and postoperative hospital stay was 14 days (Interquartile range: 11-18 days). Fifty patients (33.3%) achieved grade ≥ 2 histological responses. Regarding resection types, total/proximal gastrectomy plus splenectomy (29.8%) was associated with significantly higher morbidity than other types (distal gastrectomy, 3.2%; total/proximal gastrectomy, 4.9%; P < 0.001). Specifically, among splenectomy cases, the rate of postoperative complications associated with the laparoscopic approach was significantly higher than that associated with the robotic approach (40.0% vs. 0%, P = 0.009). In the multivariate analysis, splenectomy was an independent risk factor for postoperative complications [odds ratio, 8.574; 95% confidence interval (CI), 2.584-28.443; P < 0.001].

CONCLUSIONS

Minimally invasive gastrectomy following preoperative chemotherapy was feasible and safe for patients with highly advanced gastric cancer. Robotic gastrectomy may improve surgical safety, particularly in the case of total/proximal gastrectomy combined with splenectomy.

Chilean consensus by expert panel using the Delphi technique for primary and secondary prevention of gastric cancer

INTRODUCTION

Gastric cancer (GC) is the first cause of cancer-related death in Chile and 6th in Latin America and the Caribbean (LAC). Helicobacter pylori (H. pylori) is the main gastric carcinogen, and its treatment reduces GC incidence and mortality. Esophageal-gastro-duodenoscopy (EGD) allows for the detection of premalignant conditions and early-stage GC. Mass screening programs for H. pylori infection and screening for premalignant conditions and early-stage GC are not currently implemented in LAC. The aim of this study is to establish recommendations for primary and secondary prevention of GC in asymptomatic standard-risk populations in Chile.

METHODS

Two on-line synchronous workshops and a seminar were conducted with Chilean experts. A Delphi panel consensus was conducted over 2 rounds to achieve>80% agreement on proposed primary and secondary prevention strategies for the population stratified by age groups.

RESULTS

10, 12, and 12 experts participated in two workshops and a seminar, respectively. In the Delphi panel, 25 out of 37 experts (77.14%) and 28 out of 52 experts (53.85%) responded. For the population aged 16-34, there was no consensus on non-invasive testing and treatment for H. pylori, and the use of EGD was excluded. For the 35-44 age group, non-invasive testing and treatment for H. pylori is recommended, followed by subsequent test-of-cure using non-invasive tests (stool antigen test or urea breath test). In the ≥45 age group, a combined strategy is recommended, involving H. pylori testing and treatment plus non-invasive biomarkers (H. pylori IgG serology and serum pepsinogens I and II); subsequently, a selected group of subjects will undergo EGD with gastric biopsies (Sydney Protocol), which will be used to stratify surveillance according to the classification Operative Link for Gastritis Assessment (OLGA); every 3 years for OLGA III-IV and every 5 years for OLGA I-II.

CONCLUSION

A "test-and-treat" strategy for H. pylori infection based on non-invasive studies (primary prevention) is proposed in the 35-44 age group, and a combined strategy (serology and EGD) is recommended for the ≥45 age group (primary and secondary prevention). These strategies are potentially applicable to other countries in LAC.

Single-port intragastric wedge resection using the tunnel method: a novel surgical approach for treating endophytic gastric subepithelial tumors

BACKGROUND

Intragastric wedge resection is an effective method for treating endophytic gastric subepithelial tumors (SETs). However, retracting the stomach wall to the umbilicus is difficult in certain patients. In response, we developed a novel surgical technique for single-port intragastric wedge resection, which we termed the "tunnel method."

METHODS

A transumbilical incision is made, and a wound retractor is applied. After diagnostic laparoscopy, a gastrostomy is made on the greater curvature, lower body. Another small wound retractor is inserted into the gastrostomy, and extracted through the transumbilical incision, creating a tunnel from the gastrostomy site to the umbilicus. Articulating laparoscopic instruments are inserted via the tunnel, and intragastric wedge resection is performed. We collected and analyzed the clinicopathologic and operative data of patients who underwent intragastric wedge resection via the tunnel method.

RESULTS

Twenty-seven patients who underwent single-port intragastric wedge resection via the tunnel method in a single tertiary referral hospital were included in this study. The mean age of the patients was 54.6 ± 11.4 years, body mass index was 26.5 ± 3.4 kg/m2. Twenty-four (88.9%) patients had tumors located in the upper third of the stomach. The average operative time was 65.0 ± 24.2 min. None of the patients experienced Clavien-Dindo grade IIIa or higher postoperative complications. The average postoperative hospital stay length was 2.5 ± 0.8 days. Thirteen gastrointestinal stromal tumors, nine leiomyomas, and one neuroendocrine carcinoma, schwannoma, lipoma, spindle cell proliferative lesion, and fibrotic lesion were pathologically diagnosed. The average tumor size was 2.6 ± 1.3 cm. All cases had negative resection margins.

CONCLUSIONS

Single-port intragastric wedge resection by the tunnel method is a feasible and safe approach for treating endophytic gastric SETs.

Ex vivo treatment with poly (I:C) alleviates the exhausted phenotype of tumor-infiltrating TCD8+ cells of gastric cancer patients

Gastric cancer is associated with the phenotypic and functional exhaustion of TCD8+ cells. On the other hand, Toll-like receptor (TLR) agonists are known to reinforce immune responses when used as adjuvants in cancer immunotherapies. Since the compromised signaling of pro-inflammatory pathways is usually associated with T cell exhaustion, the aim of the present study was to evaluate the impact of polyinosinic-polycytidylic acid (poly (I:C))-mediated TLR3 activation in restoring the normal phenotype and function of tumor-infiltrating TCD8+ cells. Peripheral blood and tumor-infiltrating TCD8+ cells of 35 gastric cancer patients were in vitro treated with increasing concentrations of poly (I:C) and the expressions of programmed death-1 (PD-1) and lymphocyte-activation gene 3 (LAG3) on these cells were examined. The peripheral TCD8+ cells of gastric cancer patients showed higher expressions of PD-1 and LAG3 along with lower proliferation compared to TCD8+ cells of the age-matched healthy control individuals. The in vitro treatment of TCD8+ cells with 100 μg/mL concentration of poly (I:C) alleviated the expression of PD-1 and LAG3 inhibitory checkpoint molecules on both peripheral and tumor-infiltrating TCD8+ cells. The mentioned dose of poly (I:C) improved the proliferation of TCD8+ cells in response to a polyclonal activator. Besides, the releases of Interferon gamma (IFN-γ) and Tumor necrosis factor alpha (TNF-α) were increased in the poly (I:C)-treated TCD8+ cells. Poly (I:C) demonstrated a potential to reduce the phenotypic and functional exhaustion of the peripheral and tumor-infiltrating TCD8+ cells and caused them to undergo more proliferation and cytokine release.

Investigating FGFR2 gene as a blood-based epigenetic biomarker in gastric cancer

BACKGROUND

Gastric adenocarcinoma is a prevalent form of cancer that often remains undetected in its early stages due to the lack of specific symptoms. This delayed diagnosis leads to poor clinical outcomes, underscoring the need for an effective and non-invasive method for early detection. Recent advances in cancer epigenetics have led to the identification of biomarkers that have the potential to revolutionize the early detection and monitoring of this disease. One such promising biomarker is the methylation of the FGFR2 promoter. This study aims to measure the methylation levels of a specific CpG site in the FGFR2 promoter gene in DNA extracted from blood leukocytes from patients with intestinal metaplasia, gastric cancer, and healthy control.

MATERIAL AND METHODS

The CpG site of the FGFR2 gene promoter was identified in its control region. Methylation alteration of the selected FGFR2 CpG site was determined through the (methylation-sensitive restriction enzyme) MSRE-qPCR. Genomic DNA was extracted from one hundred twenty-five participants.

RESULTS

The normal group had mean methylation levels of 93.23 ± 4.929%, while the IM group had a level of 69.85 ± 27.15%. In GC patients, the levels varied, with 25.96 ± 18.98% in the intestinal type and 28.30 ± 16.07% in the diffuse type. The methylation levels in the IM and GC patients were significantly lower than those in the normal control group. However, no significant difference was observed between the methylation status of the intestinal type of GC and the diffuse type. The Receiver operating characteristic (ROC) curve analysis showed that FGFR2 CpG methylation levels in GC patients compared to normal controls had a high sensitivity of 100% and specificity of 100%, with a cut-off of < 74.25%; when GC patients were compared to IM patients, the sensitivity was 85%, and the specificity was 80%, with a cut-off < 44.45%.

CONCLUSIONS

The potential of the FGFR2 methylation status as a non-invasive biomarker lies in its ability to be detected in blood leukocytes, which makes it a promising tool for the early detection of intestinal metaplasia and gastric cancer. This could significantly improve the detection and management of these gastric conditions.

mRNA Expression and Methylation of the RAD51, ATM, ATR, BRCA1, and BRCA2 Genes in Gastric Adenocarcinoma

Background

Immunohistochemical prognostic significance of the homologous recombination-related proteins RAD51, ATM, BRCA1, and BRCA2 is known in gastric adenocarcinoma, one of the deadliest cancers.

Objective and design

This retrospective cohort study aimed to evaluate mRNA expression and promoter methylation of some homologous recombination-related genes in this neoplasm.

Methods

We evaluated mRNA expression and methylation of RAD51, ATM, ATR, BRCA1, and BRCA2 in tumor and non-tumor frozen samples from gastrectomy specimens by RT-qPCR and MS-HRM, correlating our results with previous immunohistochemistry data and prognostic features.

Results

RAD51, ATR, BRCA1, BRCA2, and ATM mRNA expression was detected in 93.75% (45/48), 93.75% (45/48), 91.67% (44/48), 83.33% (40/48), and 89.58% (43/48) of the tumors; partial or complete methylation, in 94.87% (37/39), 0 (0/42), 97.56% (40/41), 100% (41/41), and 0 (0/40), respectively. Most gene pairs showed significant weak to moderate positive correlations of tumoral mRNA expression with each other: RAD51 with ATR (P = .027), BRCA1 (P < .001), and BRCA2 (P < .001); ATR with BRCA1 (P = .007), and ATM (P = .001); BRCA1 with BRCA2 (P = 0.001). BRCA1 mRNA was reduced in tumors compared with non-neoplastic mucosa (0.345 vs 1.272, P = .015) and, excluding neoadjuvant therapy cases, in T3 to T4 tumors compared with T2 (0.414 vs 0.954, P = .035). Greater tumoral RAD51 mRNA levels correlated with perineural invasion (1.822 vs 0.725, P = .010) and death (1.664 vs 0.929, P = .036), but not with survival time. There was an inverse association between nuclear immunohistochemical positivity for ATR and its mRNA levels (0.487 vs 0.907, P = .032), and no significant correlation for the other markers.

Conclusions

Our results suggest RAD51, BRCA1, and BRCA2 methylation as a frequent epigenetic mechanism in gastric cancer, support the hypothesis that reduced BRCA1 expression participates in disease progression, and show an association between RAD51 mRNA and perineural invasion and mortality that may be considered unexpected, considering the former immunohistochemical studies. The lack of correlation between immunohistochemistry and mRNA, and even the inverse association, for ATR, can be seen as indicative of action of post-transcriptional or post-translational regulatory mechanisms, to be better investigated.

Phase 1/2a Study of Rivoceranib, a Selective VEGFR-2 Angiogenesis Inhibitor, in Patients with Advanced Solid Tumors

Purpose

To report the results from an early-phase study of rivoceranib, an oral tyrosine kinase inhibitor highly selective for vascular endothelial growth factor receptor 2, in patients with advanced solid tumors.

Materials and Methods

In this open-label, single-arm, dose-escalating, multicenter three-part phase 1/2a trial, patients had advanced solid tumors refractory to conventional therapy. Part 1 evaluated the safety and pharmacokinetics of five ascending once-daily doses of rivoceranib from 81 mg to 685 mg. Part 2 evaluated the safety and antitumor activity of once-daily rivoceranib 685 mg. Part 3 was conducted later, due to lack of MTD determination in part 1, to evaluate the safety and preliminary efficacy of once-daily rivoceranib 805 mg in patients with unresectable or advanced gastric cancer.

Results

A total of 61 patients were enrolled in parts 1 (n=25), 2 (n=30), and 3 (n=6). In parts 1 and 2, patients were white (45.5%) or Asian (54.5%), and 65.6% were male. The most common grade ≥3 adverse events (AEs) were hypertension (32.7%), hyponatremia (10.9%), and hypophosphatemia (10.9%). The overall response rate (ORR) was 15.2%. In part 3, dose-limiting toxicities occurred in 2 out of 6 patients: grade 3 febrile neutropenia decreased appetite, and fatigue. The ORR was 33%.

Conclusion

The recommended phase 2 dose of rivoceranib was determined to be 685 mg once daily, which showed adequate efficacy with a manageable safety profile. (NCT01497704 and NCT02711969).

Delayed Perforation Occurring after Gastric Endoscopic Submucosal Dissection: Clinical Features and Management Strategy

Background/Aims

Delayed perforation is a rare but serious adverse event of gastric endoscopic submucosal dissection (ESD). The aim of this study was to clarify the clinical features and appropriate management strategy of patients with delayed perforation.

Methods

Among 11,531 patients who underwent gastric ESD, the clinical features and outcomes of patients who experienced delayed perforation were retrospectively reviewed and compared with those of the control group.

Results

Delayed perforation occurred in 15 of 11,531 patients (0.13%). The patients with delayed perforation were significantly older than those without delayed perforation (p=0.027). The median time to diagnosis of delayed perforation was 28.8 hours (range, 14 to 71 hours). All 15 patients with delayed perforation complained of severe abdominal pain after gastric ESD and underwent subsequent chest X-rays (CXRs) for evaluation. In subsequent CXR, free air was found in 12 patients (80%). For three (20%) patients without free air in CXR, delayed perforation was finally diagnosed by computed tomography. Leukocytosis was significantly less frequent in the patients without free air in CXR (p=0.022). A perforation hole smaller than 1 cm in size was more frequently observed in the six patients who underwent successful non-surgical treatments than in the nine patients who underwent surgery (p<0.001). There was no mortality related to delayed perforation.

Conclusions

One-fifth of the patients with delayed perforation did not show free air in CXR and exhibited less leukocytosis than those with free air. Non-surgical treatments including endoscopic closure might be considered as an initial treatment modality for delayed perforation smaller than 1 cm.

Bone metastasis is a late-onset and unfavorable event in survivors of gastric cancer after radical gastrectomy: Results from a clinical observational cohort

Background

The timing and incidence of recurrent bone metastasis (BM) after radical gastrectomy in patients with gastric cancer (GC) as well as the survival of these patients were not fully understood. The aim of this study was to analyze the data of an observational GC cohort and identify patients who underwent curative gastrectomy and had recurrent BM to describe and clarify the pattern and profile of BM evolution after surgery.

Methods

Data were retrieved from a hospital-based GC cohort, and patients who underwent upfront radical gastrectomy were selected. The time points of specific organ metastatic events were recorded, and the person-year incidence rate of metastatic events was calculated. The latency period of BM events after gastrectomy was measured and compared with that of the other two most common metastatic events, liver metastasis (LM) and distant lymph node metastasis (LNM), using analysis of variance. Propensity score matching and subgroup analysis were used for sensitivity analysis.

Results

A total of 1324 GC cases underwent radical gastrectomy between January 2011 and December 2021. Of these, 67 BM, 218 LM, and 248 LNM occurred before the last follow-up. The incidence of BM events was 1.7/100 person-years, which was approximately 3-fold lower than that of LM and distant LNM events (5.5 and 6.3 per 100 person-years, respectively). BM events had a significantly longer latency (median time, 16.5 months) than LM and LNM events (11.1 and 12.0 months, respectively). Recurrent BM led to a worse prognosis (median survival, 4.5 months) than those of LM and LNM events (median survival, 7.7 and 7.1 months, respectively). However, no difference in overall survival after gastrectomy was observed among the groups.

Conclusions

Compared with other common metastatic events, BM in GC after gastrectomy is a late-onset event indicating poor survival.

Trial registration

No. ChiCTR1800019978; http://www.chictr.org.cn/.

Application of artificial intelligence for diagnosis of early gastric cancer based on magnifying endoscopy with narrow-band imaging

Although magnifying endoscopy with narrow-band imaging is the standard diagnostic test for gastric cancer, diagnosing gastric cancer using this technology requires considerable skill. Artificial intelligence has superior image recognition, and its usefulness in endoscopic image diagnosis has been reported in many cases. The diagnostic performance (accuracy, sensitivity, and specificity) of artificial intelligence using magnifying endoscopy with narrow band still images and videos for gastric cancer was higher than that of expert endoscopists, suggesting the usefulness of artificial intelligence in diagnosing gastric cancer. Histological diagnosis of gastric cancer using artificial intelligence is also promising. However, previous studies on the use of artificial intelligence to diagnose gastric cancer were small-scale; thus, large-scale studies are necessary to examine whether a high diagnostic performance can be achieved. In addition, the diagnosis of gastric cancer using artificial intelligence has not yet become widespread in clinical practice, and further research is necessary. Therefore, in the future, artificial intelligence must be further developed as an instrument, and its diagnostic performance is expected to improve with the accumulation of numerous cases nationwide.

Risk Factors of Gastric Cancer and Lifestyle Modification for Prevention

Gastric cancer has been consistently decreasing worldwide, whereas cardia gastric cancer is on the rise. This indicates that the exposure rates to epidemiological causes are changing. In this study, we aim to review the risk factors for gastric cancer with respect to cardia and non-cardia types. One of the most significant risk factors for gastric cancer is Helicobacter pylori infection. H. pylori infection is known as a risk factor for non-cardia gastric cancer, and there have been results indicating that H. pylori infection is not associated with cardia gastric cancer. However, in the East Asian region, there is epidemiological evidence suggesting that H. pylori infection might be a risk factor for cardia gastric cancer. Smoking and alcohol consumption are known risk factors for gastric cancer, regardless of anatomical location. Obesity is considered a factor in the development of cardia gastric cancer. However, further research is needed to understand the specific relationship with non-cardia gastric cancer. The consumption of high-salt and processed meat is more distinctly associated with non-cardia gastric cancer than in cardia gastric cancer. In addition to these factors, exposure to chemicals and radiation are considered risk factors for gastric cancer. Primary prevention of gastric cancer involves eliminating or avoiding risk factors such as H. pylori eradication and adopting a healthy lifestyle, including quitting smoking, reducing alcohol consumption, maintaining a healthy weight, and having a low-salt diet.

GASTric Cancer HER2 Re-Assessment Study 2 (GASTHER2): HER2 Re-assessment for Initially HER2-Negative Advanced Gastric Cancer Patients after Progression on First-Line Treatment

PURPOSE

Heterogeneous human epidermal growth factor receptor 2 (HER2) overexpression in gastric cancer may lead to a misdiagnosis of HER2 status. Accurate assessment of HER2 status is essential for optimal treatment as novel HER2-directed agents are being investigated in various clinical settings. We evaluated the usefulness of HER2 re-assessment following progression on first-line treatment in initially HER2-negative advanced gastric cancer (AGC) patients.

MATERIALS AND METHODS

We enrolled 177 patients with baseline HER2-negative AGC and performed HER2 re-assessment after progression on first-line treatment from February 2012 to June 2016 at Asan Medical Center, Seoul, Korea. The re-assessed HER2 status was analyzed with baseline HER2 status and clinical characteristics.

RESULTS

The median age was 54 years (range, 24 to 80 years), and 123 patients (69.5%) were men. Seven patients (4.0%) were HER2-positive on the re-assessment. Patients with baseline HER2 negativity confirmed by a single test (n=100) had a higher HER2-positive re-assessment rate compared to those who had repeated baseline testing (n=77) (5.0% vs. 2.6%). Among the patients with single baseline HER2 testing, the rate was higher in patients with baseline HER2 immunohistochemistry (IHC) 1+ compared to those with IHC 0 (13.4% vs. 3.6%).

CONCLUSION

Overall, 4.0% of patients with baseline HER2-negative AGC were HER2-positive on re-assessment, and the HER2-positive re-assessment rate was higher among patients who had a single test at baseline. HER2 re assessment may be considered for initially HER2-negative patients to determine their eligibility for HER2-directed therapy, particularly if their HER2 negativity was determined by a single test, especially if they had a single baseline HER2 IHC 1+ test.