Among 1676 persons with
H. pylori
infection who had family members with gastric cancer, the incidence of gastric cancer over a median follow-up of 9.2 years was significantly lower among those who ...received eradication treatment for
H. pylori
infection than among those who received placebo.
Among patients with endoscopically resected early gastric cancers who were infected with
Helicobacter pylori
, the incidence of metachronous gastric cancer was 50% lower among those who received ...active treatment with antibiotics than among controls.
In the CLASSIC and MAGIC trials, microsatellite instability (MSI)-high status was a favorable prognostic and potential negative predictive factor for neoadjuvant/adjuvant chemotherapy in resectable ...gastric cancer (GC). Given the low prevalence of MSI-high status in GC and its association with other positive prognostic variables, large data sets are needed to draw robust evidence of its prognostic/predictive value.
We performed a multinational, individual-patient-data meta-analysis of the prognostic/predictive role of MSI in patients with resectable GC enrolled in the MAGIC, CLASSIC, ARTIST, and ITACA-S trials. Prognostic analyses used multivariable Cox models (MVM). The predictive role of MSI was assessed both in an all-comer population and in MAGIC and CLASSIC trials by MVM testing of the interaction of treatment (chemotherapy plus surgery
surgery) with MSI.
MSI status was available for 1,556 patients: 121 (7.8%) had MSI-high status; 576 were European, and 980 were Asian. In MSI-high versus MSI-low/microsatellite stable (MSS) comparisons, the 5-year disease-free survival (DFS) was 71.8% (95% CI, 63.8% to 80.7%) versus 52.3% (95% CI, 49.7% to 55.1%); the 5-year overall survival (OS) was 77.5% (95% CI, 70.0% to 85.8%) versus 59.3% (95% CI, 56.6% to 62.1%). In MVM, MSI was associated with longer DFS (hazard ratio HR, 1.88; 95% CI, 1.28 to 2.76;
< .001) and OS (HR, 1.78; 95% CI, 1.17 to 2.73;
= .008), as were pT, pN, ethnicity, and treatment. Patients with MSI-low/MSS GC benefitted from chemotherapy plus surgery: the 5-year DFS compared with surgery only was 57% versus 41% (HR, 0.65; 95% CI, 0.53 to 0.79), and the 5-year OS was 62% versus 53% (HR, 0.75; 95% CI, 0.60 to 0.94). Conversely, those with MSI-high GC did not: the 5-year DFS was 70% versus 77% (HR, 1.27; 95% CI, 0.53 to 3.04), and the 5-year OS was 75% versus 83% (HR, 1.50; 95% CI, 0.55 to 4.12).
In patients with resectable primary GC, MSI is a robust prognostic marker that should be adopted as a stratification factor by clinical trials. Chemotherapy omission and/or immune checkpoint blockade should be investigated prospectively in MSI-high GCs according to clinically and pathologically defined risk of relapse.
Adjuvant chemotherapy after surgery improves survival of patients with stage II–III, resectable gastric cancer. However, the overall survival benefit observed after adjuvant chemotherapy is moderate, ...suggesting that not all patients with resectable gastric cancer treated with adjuvant chemotherapy benefit from it. We aimed to develop and validate a predictive test for adjuvant chemotherapy response in patients with resectable, stage II–III gastric cancer.
In this multi-cohort, retrospective study, we developed through a multi-step strategy a predictive test consisting of two rule-based classifier algorithms with predictive value for adjuvant chemotherapy response and prognosis. Exploratory bioinformatics analyses identified biologically relevant candidate genes in gastric cancer transcriptome datasets. In the discovery analysis, a four-gene, real-time RT-PCR assay was developed and analytically validated in formalin-fixed, paraffin-embedded (FFPE) tumour tissues from an internal cohort of 307 patients with stage II–III gastric cancer treated at the Yonsei Cancer Center with D2 gastrectomy plus adjuvant fluorouracil-based chemotherapy (n=193) or surgery alone (n=114). The same internal cohort was used to evaluate the prognostic and chemotherapy response predictive value of the single patient classifier genes using associations with 5-year overall survival. The results were validated with a subset (n=625) of FFPE tumour samples from an independent cohort of patients treated in the CLASSIC trial (NCT00411229), who received D2 gastrectomy plus capecitabine and oxaliplatin chemotherapy (n=323) or surgery alone (n=302). The primary endpoint was 5-year overall survival.
We identified four classifier genes related to relevant gastric cancer features (GZMB, WARS, SFRP4, and CDX1) that formed the single patient classifier assay. In the validation cohort, the prognostic single patient classifier (based on the expression of GZMB, WARS, and SFRP4) identified 79 (13%) of 625 patients as low risk, 296 (47%) as intermediate risk, and 250 (40%) as high risk, and 5-year overall survival for these groups was 83·2% (95% CI 75·2–92·0), 74·8% (69·9–80·1), and 66·0% (60·1–72·4), respectively (p=0·012). The predictive single patient classifier (based on the expression of GZMB, WARS, and CDX1) assigned 281 (45%) of 625 patients in the validation cohort to the chemotherapy-benefit group and 344 (55%) to the no-benefit group. In the predicted chemotherapy-benefit group, 5-year overall survival was significantly improved in those patients who had received adjuvant chemotherapy after surgery compared with those who received surgery only (80% 95% CI 73·5–87·1 vs 64·5% 56·8–73·3; univariate hazard ratio 0·47 95% CI 0·30–0·75, p=0·0015), whereas no such improvement in 5-year overall survival was observed in the no-benefit group (72·9% 66·5–79·9 in patients who received chemotherapy plus surgery vs 72·5% 65·8–79·9 in patients who only had surgery; 0·93 0·62–1·38, p=0·71). The predictive single patient classifier groups (chemotherapy benefit vs no-benefit) could predict adjuvant chemotherapy benefit in terms of 5-year overall survival in the validation cohort (pinteraction=0·036 in univariate analysis). Similar results were obtained in the internal evaluation cohort.
The single patient classifiers validated in this study provide clinically important prognostic information independent of standard risk-stratification methods and predicted chemotherapy response after surgery in two independent cohorts of patients with resectable, stage II–III gastric cancer. The single patient classifiers could complement TNM staging to optimise decision making in patients with resectable gastric cancer who are eligible for adjuvant chemotherapy after surgery. Further validation of these results in prospective studies is warranted.
Ministry of ICT and Future Planning; Ministry of Trade, Industry, and Energy; and Ministry of Health and Welfare.
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Lauren diffuse-type gastric adenocarcinomas (DGAs) are generally genomically stable. We identified lysine (K)-specific methyltransferase 2C (
) as a frequently mutated gene and examined its role in ...DGA progression.
We performed whole exome sequencing on tumor samples of 27 patients with DGA who underwent gastrectomy. Lysine (K)-specific methyltransferase 2C (
) was analyzed in DGA cell lines and in patient tumors.
was the most frequently mutated gene (11 of 27 tumors 41%). KMT2C expression by immunohistochemistry in tumors from 135 patients with DGA undergoing gastrectomy inversely correlated with more advanced tumor stage (
= 0.023) and worse overall survival (
= 0.017). KMT2C shRNA knockdown in non-transformed HFE-145 gastric epithelial cells promoted epithelial-to-mesenchymal transition (EMT) as demonstrated by increased expression of EMT-related proteins N-cadherin and Slug. Migration and invasion in gastric epithelial cells following KMT2C knockdown increased by 47- to 88-fold. In the DGA cell lines MKN-45 and SNU-668, which have lost KMT2C expression, KMT2C re-expression decreased expression of EMT-related proteins, reduced cell migration by 52% to 60%, and reduced cell invasion by 50% to 74%. Flank xenografts derived from KMT2C-expressing DGA organoids, compared with wild-type organoids, grew more slowly and lost their infiltrative leading edge. EMT can lead to the acquisition of cancer stem cell (CSC) phenotypes. KMT2C re-expression in DGA cell lines reduced spheroid formation by 77% to 78% and reversed CSC resistance to chemotherapy via promotion of DNA damage and apoptosis.
is frequently mutated in certain populations with DGA. KMT2C loss in DGA promotes EMT and is associated with worse overall survival.
Circulating tumor DNA (ctDNA) has emerged as a candidate biomarker for cancer screening. However, studies on the usefulness of ctDNA for postoperative recurrence monitoring are limited. The present ...study monitored ctDNA in postoperative blood by employing cancer-specific rearrangements. Personalized cancer-specific rearrangements in 25 gastric cancers were analyzed by whole-genome sequencing (WGS) and were employed for ctDNA monitoring with blood up to 12 months after surgery. Personalized cancer-specific rearrangements were identified in 19 samples. The median lead time, which is the median duration between a positive ctDNA detection and recurrence, was 4.05 months. The presence of postoperative ctDNA prior to clinical recurrence was significantly correlated with cancer recurrence within 12 months of surgery (P = 0.029); in contrast, no correlation was found between cancer recurrence and the presence of preoperative ctDNA, suggesting the clinical usefulness of postoperative ctDNA monitoring for cancer recurrence in gastric cancer patients. However, the clinical application of ctDNA can be limited by the presence of ctDNA non-shedders (42.1%, 8/19) and by inconsistent postoperative ctDNA positivity.
Undifferentiated-type carcinoma has a high incidence of lymph node metastasis. The independent risk factors for lymph node metastasis in undifferentiated-type carcinoma are invasion depth, tumor ...size, lymphovascular invasion, and presence of ulcer. In the cases that meet the curative resection criteria, no lymph node metastasis was observed in the Japanese studies, but some metastases were observed in Korean studies. After performing curative endoscopic submucosal dissection, the survival rate is similar to that of gastrectomy. The discrepancy between endoscopy and pathology is high in undifferentiated-type carcinoma. The tumor size in endoscopy is a significant risk factor for non-curative resection, and when the tumor size is small, the non-curative resection rate is significantly reduced. Lymphovascular invasion can be assessed in pathologic examination and D2-40 stain is helpful. The presence of ulcer should be determined by pathology, but ulcer's omission in pathology report makes the analysis difficult. Undifferentiatedtype carcinomas with differentiated-type components show higher lymph node metastasis rate than that of pure undifferentiatedtype carcinomas. The lymph node metastasis rate of signet ring cell type is lower than that of other undifferentiated-type carcinomas and is similar to differentiated-type carcinomas. The application of these additional histologic findings may improve the indication of endoscopic submucosal dissection.
Background Endoscopic resection (ER) of early gastric cancer (EGC) meeting the absolute indication has excellent long-term outcomes. Objective To compare long-term outcomes of ER with those of ...surgery in patients with EGC who met the absolute indication for ER. Design Retrospective cohort study. Setting A specialized center for the treatment of cancer. Patients and Interventions We retrospectively reviewed data from patients who underwent gastrectomy or ER for EGC between 2002 and 2007. Gastric cancers were differentiated-type adenocarcinoma without ulceration confined to the mucosal layer and 2 cm or smaller in size. Main Outcome Measurements The primary outcome was overall survival (OS). Metachronous cancer rates and adverse event rates were compared. Kaplan-Meier plots and Cox proportional hazard regression analyses were applied for comparisons. Differences in baseline characteristics were adjusted by propensity score. Results Among 375 patients, 261 underwent ER and 114 underwent surgery. The median follow-up duration was 76.4 months. The 5-year OS rates did not significantly differ between the ER and surgery groups (95.7% vs 93.6%, respectively; P = .725 by log-rank test). There were no gastric cancer–related deaths in either group. Metachronous gastric cancer developed more frequently in the ER group (6.1%, 16/261) than in the surgery group (0.9%, 1/114) ( P = .024). However, most patients (93.8%, 15/16) in the ER group were curatively treated with repeat ER. Adverse event rates were higher in the surgery group than those in the ER group (7.9% vs 2.7%, P = .028). Limitations Retrospective, single-center study. Conclusions The OS rate after ER for mucosal gastric cancer that met the absolute indication was comparable to that achieved with surgery. Although metachronous cancers were more common after ER, they were usually treatable and did not affect survival.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Greater lymph node retrieval in gastric cancer improves staging accuracy and may improve survival from increased clearance of nodal micrometastasis. This retrospective cohort study investigated if ...more lymph nodes removed in gastric cancer increases survival and if such effect is stage-specific due to differential risks of nodal micrometastasis and systemic disease.
The prospectively collected database of curatively resected gastric cancer patients in National Cancer Center, South Korea between 2000 and 2009 was reviewed. Disease-free survival (DFS) and overall survival (OS) for all patients and for each stage according to number of lymph nodes examined (1-30, 31-45, > 45) were analyzed.
Of 4049 patients, 96.6% and 98.4% underwent D2 (perigastric and extragastric) lymphadenectomy and had ≥ 15 lymph nodes examined. Mean number of nodes examined was 43. Five-year OS & DFS rates were 83.3% and 80.7%. Patients with > 45 nodes examined had significantly lower DFS (p = 0.002) and OS (p = 0.007) compared to those with 1-30 and 31-45 nodes. However, proportion of patients with > 45 nodes examined increased with stage (p = 0.0005). Per stage, there was no significant difference in DFS and OS according to number of nodes examined except for stage IIIA favoring more nodes (p = 0.018 and p = 0.044, respectively). Similar trend was seen in stage IIB. Number of examined nodes positively correlated with number of pathologic nodes for all patients (r = 0.144, p < .001) but not for stage IIB and IIIA. Number of nodes examined was a significant survival predictor in stage IIIA.
Greater lymph node harvest showed improved survival in intermediate-stage gastric cancer.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Intestinal-type gastric cancer often results from
infection through intestinal metaplasia, a transdifferentiated premalignant phenotype. Because
virulence factor CagA has been associated with ...aberrant expression of the transcription factor CDX1, which regulates intestinal differentiation, we explored its relationship with
infection and function during gastric carcinogenesis in normal gastric epithelial cells and gastric cancer cell lines. Infection of HFE 145 cells with CagA
increased expression of CDX1, as well as the epithelial-to-mesenchymal transition (EMT) markers Snail and Slug, increased invasion and migration, but those effects were not found in HFE 145 cells infected with CagA-deficient
. CDX1 overexpression increased expression of the intestinal markers Villin, sucrose isomaltase (SI), and MUC2, induced spheroid formation, and enhanced expression of the stem cell markers CD44, SOX2, Oct4, and Nanog, while CDX1 knockdown inhibited proliferation and intestinal stemness. Treatment of CDX1-expressing cells with metformin, an antidiabetic drug known to decrease the risk of gastric cancer, decreased expression of EMT and stemness markers, and reduced spheroid formation. In a murine xenograft model, combining metformin or shCDX1 with cisplatin reduced tumor growth, increased caspase-3 cleavage, and reduced expression of CD44 and MMP-9 to a greater degree than cisplatin alone. Patients with more advanced intestinal metaplasia staging exhibited higher CDX1 expression than those with earlier intestinal metaplasia staging (
= 0.039), and those with
tended to have more CDX1 expression than noninfected patients (
= 0.061). Finally, human tissue samples with higher CDX1 levels showed prominent CD44/SOX2 expression. Our findings indicate CagA
-induced CDX1 expression may enhance gastric cancer tumorigenesis and progression, and support therapeutic targeting of CDX1 in gastric cancer. IMPLICATIONS: This study shows that CDX1 contributes to the tumorigenesis and progression of gastric cancer and suggests the potential of targeting CDX1 to treat this malignancy.
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