Helicobacter pylori-associated Chronic Atrophic Gastritis and Progression of Gastric Carcinogenesis.

Chronic inflammation due to a Helicobacter pylori (H. pylori) infection is a representative cause of gastric cancer that can promote gastric carcinogenesis by abnormally activating immune cells and increasing the inflammatory cytokines levels. H. pylori infections directly cause DNA double-strand breaks in gastric epithelial cells and genetic damage by increasing the enzymatic activity of cytidine deaminase. Eventually, gastric cancer is induced through dysplasia. Hypermethylation of tumor suppressor genes is an important cause of gastric cancer because of a H. pylori infection. In addition, the changes in gastric microbiota and the mucosal inflammatory changes associated with a co-infection with the Epstein-Barr virus are associated with gastric cancer development. DNA damage induced by H. pylori and the subsequent responses of gastric stem cells have implications for gastric carcinogenesis. Although the pathogenesis of H. pylori has been established, many uncertainties remain, requiring more study.

[The Present Status and Improvement Directions for Gastrointestinal Fellows and Residents in Korea].

The Korean Society of Gastroenterology (KSG) and the Korean Society of Gastrointestinal Endoscopy (KSGE) have tried to promote high-quality patient care, and safety in the field of gastrointestinal (GI) diseases. In 2017, the training guidelines for GI fellows have been made, and the education board of KSGE revised 2 year- program of GI fellows. The guideline includes the total number of assigned patients, the number of GI endoscopy procedures, attendance of academic conferences, and research presentations. The traditional training model of GI fellowship is known as an "apprenticeship". Unfortunately, it might increase confusion between what trainees are observing and prior information. Now, practical hands-on training system using simulator helps to provide a support program for GI fellowship education. In order to facilitate training program, trainers will need to carefully plan the teaching. Therefore, it improves knowledge and performance for trainers. What we should keep in mind is that this hands-on program has the goal of making a good gastroenterologist, not just making an endoscopist. At same time, the application of cognitive education in GI fellow training must be performed. On the other side, the privileging and credentialing for endoscopic subspecialty should be made. The provision of benefits could serve as an important foundation for maintaining GI specialist board system.

Clinical outcomes of metachronous recurrence of gastric epithelial neoplasia based on Helicobacter pylori infection status and microsatellite stability.

BACKGROUND/AIMS: Helicobacter pylori eradication may prevent the recurrence of gastric epithelial neoplasia after endoscopic treatment. However, H. pylori eradication therapy is unlikely to prevent gastric cancer. This study determined the longterm results and clinical outcomes of patients with gastric epithelial neoplasia based on H. pylori infection status and microsatellite stability (MSS). METHODS: Patients diagnosed with gastric epithelial neoplasia who underwent an endoscopic mucosal resection or submucosal dissection between 2004 and 2010 were included in this retrospective study. During the follow-up period (range, 4 to 14 years), disease recurrence was monitored, and tissue examinations were conducted for seven sets of microsatellite loci initially linked to the tumour suppressor gene locus. When H. pylori infection was identified, patients underwent eradication therapy. RESULTS: The patients (n = 120) were divided into three groups: H. pylori-negative with MSS, H. pylori-positive with MSS, and microsatellite instability (MSI). After H. pylori eradication, the rate of metachronous recurrence was significantly different in the MSI (28.2%) and MSS groups (3.7%, p < 0.01). The mean duration of recurrence was 77 months (range, 24 to 139) in the MSI group. There was no recurrence after eradication therapy in patients who were positive for H. pylori in the MSS group. CONCLUSION: H. pylori eradication could help prevent gastric cancer recurrence in patients with stable microsatellite loci. Careful, long-term monitoring is required in patients with unstable microsatellite loci.

Vonoprazan non-inferior to lansoprazole in treating duodenal ulcer and eradicating Helicobacter pylori in Asian patients.

BACKGROUND AND AIM: Duodenal ulcers, especially caused by increasingly drug-resistant Helicobacter pylori, are a concern in Asia. We compared oral vonoprazan versus lansoprazole for efficacy (healing duodenal ulcers) and safety in non-Japanese Asian patients. METHODS: In this phase 3, randomized (1:1), double-blind, double-dummy, parallel-group, non-inferiority study (April 5, 2017, to July 19, 2019), patients with ≥ 1 endoscopically confirmed duodenal ulcer, at 52 hospitals (China, South Korea, and Taiwan), received vonoprazan 20 mg once daily (QD) or lansoprazole 30 mg QD for 6 weeks maximum. Patients with H. pylori received bismuth-containing quadruple therapy including vonoprazan 20 mg twice daily (BID) or lansoprazole 30 mg BID, for 2 weeks, followed by vonoprazan or lansoprazole monotherapy QD (4 weeks maximum). Endpoints were endoscopically confirmed duodenal ulcer healing (Week 4/6; primary) and H. pylori eradication (4 weeks post-treatment; secondary); non-inferiority margins were -6% and -10%, using a two-sided 95% confidence interval (CI). RESULTS: Of 533 enrolled patients, one was lost to follow-up and one withdrew (full analysis set: 531 patients [vonoprazan, n = 263; lansoprazole, n = 268]; 85.4% = H. pylori positive). Vonoprazan was non-inferior to lansoprazole for duodenal ulcer healing (96.9% vs 96.5%; difference 0.4% [95% CI -3.00, 3.79]). H. pylori eradication rates were 91.5% (vonoprazan) and 86.8% (lansoprazole; difference 4.7% [95% CI -1.28, 10.69]). Vonoprazan and lansoprazole were well tolerated, with similar safety profiles, no new safety signals; no deaths occurred. CONCLUSIONS: Vonoprazan was well tolerated and non-inferior to lansoprazole for duodenal ulcer healing and achieved H. pylori eradication above the clinically meaningful threshold (90%), in non-Japanese Asian patients.

HER-2 positivity is a high risk of recurrence of stage I gastric cancer.

BACKGROUND/AIMS: The treatment of gastric cancer remains unsatisfactory. We aimed to investigate the prognostic value of immunohistochemical staining in gastric cancer. METHODS: We analyzed 505 (279 early staged, 226 advanced-staged) gastric cancer tissues from patients who underwent radical gastric resection between January 2014 and December 2016. Available surgical specimens immunohistochemically stained for p53, epidermal growth factor receptor (EGFR), human EGFR 2 (HER-2), E-cadherin, and Ki-67 were reviewed. We evaluated the association between positivity to various biomarkers and disease recurrence, disease-free survival, lymph node metastasis, and microscopic lymphovascular invasion. RESULTS: The median follow-up duration was 32.5 months (range, 7 to 70). Advanced gastric cancer cases showed high Ki-67 expression; other cases showed unremarkable expression. Concerning disease recurrence, lymphatic invasion, and disease-free interval, all biomarkers had no prognostic effects. HER-2-positive stage I gastric cancer tended to occur in old patients and in the upper one-third of the stomach (p = 0.01). HER-2 positivity was significantly correlated with disease recurrence (p = 0.01), lymphatic invasion (p = 0.03), and vascular invasion (p = 0.03) in stage I cases. CONCLUSION: Only HER-2 was associated with the recurrence of stage I gastric cancer. HER-2-positive stage I gastric cancer requires additional therapy despite curative resection.

Effect of prophylactic clip application for the prevention of postpolypectomy bleeding of large pedunculated colonic polyps: a randomized controlled trial.

BACKGROUND AND AIMS: Prophylactic application of a hemoclip has been suggested as an alternative to the use of an endoloop for the prevention of postpolypectomy bleeding (PPB) when resecting large, pedunculated colorectal polyps. Therefore, this multicenter, randomized controlled trial investigated the efficacy of prophylactic hemoclip application to reduce PPB during the resection of large pedunculated polyps. METHODS: Large pedunculated polyps (≥10 mm in head diameter) were eligible for inclusion. Polyps were randomized into a study arm (where clips were applied before resection) and a control arm (without pretreatment). The primary outcome was the rate of PPB in each group. PPB included immediate PPB (IPPB) and delayed PPB (DPPB). IPPB was defined as blood oozing (≥1 minute) or active spurting occurring immediately after polyp resection. DPPB was defined as rectal bleeding, occurring after completion of the colonoscopy. RESULTS: In total, 238 polyps from 204 patients were randomized into the clip arm (119 polyps) or the control arm (119 polyps). Overall bleeding adverse events were observed in 20 cases (IPPB, 16; DPPB, 4). The rate of overall PPB, IPPB, and DPPB was 8.4%, 6.7%, and 1.7%, respectively, for all polyps. The rate of overall PPB (clip 4.2% vs control 12.6%, P = .033) and IPPB (clip 2.5% vs control 10.9%, P = .017) was significantly lower in the clip arm than the control arm. CONCLUSIONS: Prophylactic clipping before resecting large pedunculated polyps can reduce overall PPB and IPPB compared with no prior treatment. Therefore, prophylactic clipping may be considered before resection of large pedunculated polyps. (Clinical trial registration number: NCT02156193.).

Clinical Outcomes of Mucinous Gastric Carcinomas Compared with Non-mucinous and Signet Ring Cell Carcinomas.

Background/Aims: This study examined the clinical features and prognosis of patients with mucinous gastric carcinoma (MGC), non-mucinous gastric carcinoma (NMGC), and signet ring cell gastric carcinoma (SRC). Methods: A retrospective cohort study was performed, enrolling 65 patients with MGC from January 2007 to December 2016. During the same period, 1,814 patients with histologically proven gastric cancers underwent curative or palliative operations. One hundred and ninety-five NMGC patients were selected as the 1:3 age- and sex-matched control groups. In addition, 200 SRC patients were identified. This study evaluated the demographic features of the patients, pathologic features of the tumor, and the predictive factors, such as the recurrence-free survival and overall survival. Results: The recurrence rates were significantly high in MGC than in NMGC or SRC (both p<0.01). The proportion of early gastric cancer was lower in the MGC group than in the other groups (p<0.01). In addition, metastatic lymph nodes were found more frequently in the MGC group (p<0.01), and the proportion of initial pT4, M1 stage, was highest in the MGC group. The recurrence-free survival and overall survival in the MGC group were significantly lower than those in the NMGC or SRC. Subgroup analysis showed that patients with the same American Joint Committee on Cancer (AJCC) stage of each cancer group showed a similar prognosis. Conclusions: MGC frequently presents an advanced stage with an unfavorable prognosis compared to NMGC or SRC. On the other hand, MGC of the same AJCC stage had a similar prognosis to NMGC and SRC.

Treatment pattern and overall survival in esophageal cancer during a 13-year period: A nationwide cohort study of 6,354 Korean patients.

Using data from the real world to solve clinical questions that cannot be answered using data from clinical trials is attracting more attention. Clinical outcomes for patients with esophageal cancer in a real-world setting might be different from data in randomized controlled trials. This study aimed to provide real world data on treatment and prognosis in Korean patients with esophageal cancer. This retrospective cancer cohort included newly diagnosed cases of esophageal cancer at 19 tertiary hospitals between January 1, 2005 and December 31, 2017. Cancer staging was defined according to the 7th edition of the American Joint Committee on Cancer criteria. We identified 6,354 patients with newly diagnosed esophageal cancer (mean age: 64.9 ± 9.0 years, 96.9% squamous cell carcinoma). The proportion of early esophageal cancer increased from 24.7% in 2005 to 37.2% in 2015 (p<0.001). Among all cases, surgery alone was 31.3%, followed by definitive concurrent chemoradiotherapy (CCRT) (27.0%), neoadjuvant therapy (12.4%), adjuvant therapy (11.1%), and endoscopic resection (5.8%). The 5-year overall survival rate was 45.7 ± 0.7%. Endoscopic resection provided similar median survival relative to surgery for stage Ia cases. Among stage II-III cases, definitive CCRT was associated with poorer survival than neoadjuvant or adjuvant therapy, although there was no survival difference between neo-adjuvant and adjuvant therapy. Early esophageal cancer is gradually becoming more common and endoscopic resection provided similar long-term survival relative to surgery. Surgery with combined therapy provided better survival in locally advanced esophageal cancer, relative to definitive CCRT.

Prognostic effect of different etiologies in patients with gastric cardia cancer.

There are still many controversies about the characteristics and prognosis of gastric cardia cancer. We aimed to evaluate the clinical characteristics and outcome between cardia and noncardia cancer. Also, we evaluated the clinical outcome according to etiologic factors.We performed a retrospective cohort study of 92 patients with gastric cardia cancer from January 2003 to December 2013. The patients with noncardia cancer were selected as age- and sex-matched control.The frequencies of gastroesophageal reflux disease (GERD) and negative Helicobacter pylori infection without atrophy were significantly higher in gastric cardia cancers, but there was no difference in the frequency of obesity. The frequency of early gastric cancers was 40.0%, which was significantly lower than that of noncardia cancer. The rate of recurrence, disease-free survival, and overall survival duration were significantly lower in gastric cardia cancers (P < .01), even though there was no significant difference in the rate of curative resection (R0). In terms of the etiologic factors, there were no differences of disease prognosis, regardless of the presence of GERD, obesity, and H pylori infection with associated gastritis.Gastric cardia cancer showed distinct clinical characteristics and a negative prognostic impact compared with gastric noncardia cancer.

Does Colonic Diverticulosis Raise the Risk of Colorectal Adenoma in Patients with Colorectal Cancer?

BACKGROUND: The aim of this study was to evaluate the risk of development of colorectal adenomas in patients with colorectal cancer (CRC) with and without colonic diverticulosis. METHODS: We performed a retrospective cohort study that included patients with CRC between 2008 and 2011. All patients underwent preoperative colonoscopic and barium enema examinations. Follow-up colonoscopic examinations were performed within 1 year and between 3 and 5 years postoperatively. The incidence of colorectal adenomas was compared based on the presence or absence of diverticulosis. Additionally, multivariate logistic regression analysis was performed to identify the factors independently associated with the development of synchronous and metachronous colorectal adenomas. RESULTS: Of the 168 patients with CRC included in the study, 55 showed colonic diverticulosis. Synchronous colorectal adenomas were more common in CRC patients with diverticulosis than in those without diverticulosis (P > 0.001). Multivariate regression analysis showed that colonic diverticulosis (odds ratio (OR) 3.874, 95% confidence interval (CI) 1.843-8.144, P > 0.001) and obesity (body mass index > 25.0 kg/m2, OR 2.395, 95% CI 1.089-5.270, P = 0.030) were associated with an increased risk of synchronous colorectal adenomas. The presence of synchronous colorectal adenomas increased the risk of metachronous colorectal adenomas (OR 4.407, 95% CI 1.855-10.473, P > 0.001). CONCLUSIONS: Colonic diverticulosis was associated with synchronous colorectal adenomas in patients with CRC, which is eventually increasing the risk of metachronous adenomas.

The predictive factors of gastric cancer recurrence after the completion of adjuvant chemotherapy in advanced gastric cancer.

OBJECTIVE: the administration of adjuvant chemotherapy after a curative resection is accepted as the standard treatment to improve the prognosis of advanced gastric cancer. Nevertheless, the prognosis of recurrence-related gastric cancer is still not clinically satisfactory. We aimed to assess the therapeutic yield of a radical gastrectomy with D2 lymphadenectomy (R0 resection) and the completion of adjuvant chemotherapy. The predictive risk factors for recurrence were also assessed. METHODS: a retrospective cohort study was designed with patients diagnosed with advanced gastric cancer. Patients with an R0 resection who had completed adjuvant chemotherapy were included in the study. RESULTS: data from 130 patients who had undergone an R0 resection and had completed six cycles of adjuvant chemotherapy were analyzed. The chemotherapy compliance rate was 63.11% and the overall recurrence rate was 36.9%. The lymph node ratio (LNR), which was defined as the number of metastatic lymph nodes divided by the retrieved lymph nodes, was a significant risk factor in the lymph node-positive group (p < 0.01). This parameter had a relatively high sensitivity to predict recurrence compared with the 7th and 8th edition of the AJCC staging system, with an area under the curve of 0.735 (95% confidence interval: 0.639-0.832). Baseline CA19-9 level was a risk factor in the lymph node-negative group (p = 0.01). CONCLUSIONS: LNR and baseline CA19-9 levels, as simple markers, had strong predictive values for the recurrence of advanced gastric cancer. With regard to recurrence, more potent adjuvant therapy should be considered in high-risk patients.

Genetic polymorphisms of vascular endothelial growth factor (VEGF) associated with gastric cancer recurrence after curative resection with adjuvant chemotherapy.

BACKGROUND: The relationship between polymorphisms in vascular endothelial growth factor (VEGF) and gastric cancer is still inconclusive. We investigated whether there is an association between VEGF genetic polymorphisms and risk of gastric cancer, and evaluated the recurrence of advanced gastric cancer after curative resection with adjuvant chemotherapy according to VEGF genetic polymorphisms. METHODS: The association of functional single nucleotide polymorphisms (SNPs) of the VEGF gene (+936C > T, - 634G > C, - 2578C > A, + 1612G > A) were evaluated. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. A total of 151 patients with gastric cancer were enrolled, and the control group consisted of 413 individuals with esophago-gastroduodenoscopy who were randomly selected through health screening. All of the enrolled patients had curative resections with completion of adjuvant capecitabine and oxaliplatin combination chemotherapy and the initial metastatic cases were excluded. During the regular follow-up protocol, the episodes of the recurrence were documented and the specific genotype and allelic frequencies were evaluated. RESULTS: As for the cancer risk, there were no significant differences in specific genotypes and allelic frequencies. The mean follow-up period was 28.82 ± 30.92 (12 ~ 72) months and the recurrence rate was 28.3%. In the patients carrying the 936-C allele, the recurrence rate of gastric cancer was high (P = 0.02). Disease-free interval was significantly different between the patients carrying the 936-CC and 936-CT/TT genotype (P = 0.02). CONCLUSIONS: VEGF 936-C allele is associated with poor prognosis, but not risk of gastric cancer. In the patients carrying the 936-C allele, more potent adjuvant treatment would be considered.

The usefulness of fecal calprotectin in assessing inflammatory bowel disease activity.

BACKGROUND/AIMS: Fecal calprotectin (FC) is known to correlate with disease activity and can be used as a predictor for relapse or treatment response in inflammatory bowel disease (IBD). We evaluated the usefulness of FC as a biomarker for disease activity in patients with IBD using both enzyme-linked immunosorbent assay (ELISA) and a quantitative point-of-care test (QPOCT). METHODS: Fecal samples and medical records were collected from consecutive patients with IBD. FC levels were measured by both ELISA and QPOCT and patient medical records were reviewed for clinical, laboratory, and endoscopic data. RESULTS: Ninety-three patients with IBD were enrolled, 55 with ulcerative colitis (UC) and 38 with Crohn's disease (CD). The mean FC-ELISA levels were 906.3 ± 1,484.9 µg/g in UC and 1,054.1 ± 1,252.5 µg/g in CD. There was a strong correlation between FC-ELISA level and clinical activity indices (p < 0.05). FC-ELISA level was significantly lower in patients with mucosal healing (MH) compared to those without MH in UC (85.5 ± 55.6 µg/g vs. 1,503.7 ± 2,129.9 µg/g, p = 0.005). The results from the QPOCT corresponded well to those from ELISA. A cutoff value of 201.3 µg/g for FC-ELISA and 150.5 µg/g for FC-QPOCT predicted endoscopic inflammation (Mayo endoscopic subscore ≥ 1) in UC with a sensitivity of 81.8% and 85.8%, respectively, and a specificity of 100% for both. CONCLUSION: FC was strongly associated with disease activity indices, serologic markers, and endoscopic activity in patients with IBD. QPOCT can be used more conveniently than ELISA to assess FC in clinical practice.

Early Detection is Important to Reduce the Economic Burden of Gastric Cancer.

PURPOSE: Early detection of gastric cancer is important to improve prognosis. Early detection enables local treatment, such as endoscopic submucosal dissection (ESD). Therefore, we investigated whether early detection of gastric cancer could reduce healthcare costs by comparison according to stage and treatment modalities. MATERIALS AND METHODS: Medical care costs were investigated according to tumor stage and initial treatment modality in 1,188 patients newly diagnosed with gastric cancer at 7 medical institutions from December 2011 to June 2012. Total medical care costs during the first-year after diagnosis (total first-year costs) were examined, including the costs of initial treatment, post-initial treatment, and inpatient and outpatient visits. RESULTS: Stage I (75.3%) was the most common cancer stage. ESD was the second most common treatment following surgery. Total first-year costs increased significantly from stages I to IV. The costs of initial treatment and post-initial treatment were lowest in patients with stage I cancer. Among patients with stage I cancer, total first-year costs were significantly lower when treated by ESD; in particular, initial ESD treatment costs were much lower than others. CONCLUSIONS: The cost of healthcare has increased significantly with increasing cancer stages. ESD can greatly reduce medical care costs of gastric cancer. Thus, early detection of gastric cancer is important to reduce healthcare costs.

Factors Associated with Rebleeding in Patients with Peptic Ulcer Bleeding: Analysis of the Korean Peptic Ulcer Bleeding (K-PUB) Study.

BACKGROUND/AIMS: Rebleeding is associated with mortality in patients with peptic ulcer bleeding (PUB), and risk stratification is important for the management of these patients. The purpose of our study was to examine the risk factors associated with rebleeding in patients with PUB. METHODS: The Korean Peptic Ulcer Bleeding registry is a large prospectively collected database of patients with PUB who were hospitalized between 2014 and 2015 at 28 medical centers in Korea. We examined the basic characteristics and clinical outcomes of patients in this registry. Univariate and multivariate analyses were performed to identify the factors associated with rebleeding. RESULTS: In total, 904 patients with PUB were registered, and 897 patients were analyzed. Rebleeding occurred in 7.1% of the patients (64), and the 30-day mortality was 1.0% (nine patients). According to the multivariate analysis, the risk factors for rebleeding were the presence of co-morbidities, use of multiple drugs, albumin levels, and hematemesis/hematochezia as initial presentations. CONCLUSIONS: The presence of co-morbidities, use of multiple drugs, albumin levels, and initial presentations with hematemesis/hematochezia can be indicators of rebleeding in patients with PUB. The wide use of proton pump inhibitors and prompt endoscopic interventions may explain the low incidence of rebleeding and low mortality rates in Korea.

[Micrometastasis in Gastric Cancer].

Although the incidence and mortality rate of gastric cancer have been steadily declining, gastric cancer is still the fourth most common cancer in the world and more than 50% of cases occur in Eastern Asia. In Korea, gastric cancer is the second most common cancer and third cause of cancer related death. The standard surgical procedure for resectable advanced gastric cancer is D2 lymphadenectomy with radical gastrectomy. Even though R0 resection was completed, recurrence is relatively common, and contributes to the limited survival of the patients in gastric cancer. As a clinically relevant factor for detection of the recurrence, the presence of isolating tumor cells has been introduced and it is so called as 'micrometastasis'. Numerous immunohistochemistry and molecular studies have shown that micrometastasis can be demonstrated not only in lymph nodes but also in such body compartments as the bone marrow, peritoneal cavity and blood. Herein, we review the current knowledge and evidence of the prognostic significance of micrometastasis in peritoneal, lymph node, bone marrow. Also, we discuss the current state of research on the circulating tumor cell in peripheral blood.

The Detection of Messenger RNA for Carcinoembryonic Antigen and Cytokeratin 20 in Peritoneal Washing Fluid in Patients with Advanced Gastric Cancer.

BACKGROUND/AIMS: Peritoneal micrometastasis is known to play an important role in the recurrence of gastric cancer. However, its effects remain equivocal. Herein, we examine the messenger RNA (mRNA) as tumor markers, carcinoembryonic antigen (CEA), and cytokeratin 20 (CK20), in peritoneal washing fluid. Moreover, we evaluate whether these results could predict the recurrence of gastric cancer following curative resection. METHODS: We prospectively enrolled 132 patients with gastric cancers, who had received an operation, between January 2010 and January 2013. The peritoneal lavage fluid was collected at the operation field and semi-quantitative PCR was performed using the primers for CEA and CK20. We excluded patients with stage IA (n=28) early gastric cancer, positive cytologic examination of peritoneal washings (n=7), and those who were lost during follow up (n=18). RESULTS: A total of 79 patients with gastric cancers were enrolled, and the mean follow-up period was 39.95±19.25 months (range, 5-72 months). According to the multivariate analysis, T4 stage at the initial diagnosis was significantly associated with recurrence. All cases of recurrence were CEA positive and 6 cases were CK20 positive. The positive and negative predictive values of CEA were 32.0% and 100%, respectively, whereas those of CK20 were 37.5% and 71.4%, respectively. Disease free survival of CK20-negative cases was 36.17±20.28 months and that of CK20-positive cases was 32.06±22.95 months (p=0.39). CONCLUSIONS: It is unlikely that the real time polymerase chain reaction results of mRNA for CEA and CK20 in peritoneal washing fluid can predict recurrence. However, negative results can convince surgeons to perform curative R0 resection.