Low Absolute Lymphocyte Count Correlates with Lymph Node Metastases and Worse Survival of Patients with Gastric Cancer.

BACKGROUND: Several studies have found that the absolute lymphocyte (ALC) or neutrophil count predicts the survival of patients with solid tumors, and that the neutrophil-to-lymphocyte ratio and the prognostic nutritional index are useful markers of gastric cancer prognosis. However, it remains unclear whether the ALC is prognostic of lymph node (LN) metastasis in patients with gastric cancer. In this study, we aimed to explore the impact of ALC on prognosis and distinctive clinical characteristics in patients with gastric cancer. PATIENTS AND METHODS: The medical records of patients with gastric adenocarcinomas who underwent radical gastrectomy with curative intent at Seoul St. Mary's Hospital and Yeouido St. Mary's Hospital between January 2010 and December 2017 were reviewed. Of these, 4149 patients for whom preoperative white blood cell, neutrophil, and lymphocyte counts were available were enrolled. RESULTS: In all 4149 patients, ALC gradually decreased as the pN stage increased. Those with an ALC of less than 1360 cells/µL were defined as a low-ALC group, and advanced cT and cN stages were the strongest risk factors for LN metastasis in both univariate and multivariate analyses; undifferentiated tumor histology and a low ALC were also significant risk factors. Patients of all stages in the ALC-low group exhibited poorer prognoses. The ALC-low group also exhibited a higher recurrence rate in a greater proportion of LNs. CONCLUSIONS: In patients with gastric cancer, as the preoperative ALC decreases, the incidence of LN metastasis increases. A low ALC is associated with a high recurrence rate, particularly in LNs.

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

OBJECTIVE: We sought to define criteria associated with low lymph node metastasis risk in patients with submucosal (pT1b) gastric cancer from 3 Western and 3 Eastern countries. SUMMARY BACKGROUND DATA: Accurate prediction of lymph node metastasis risk is essential when determining the need for gastrectomy with lymph node dissection following endoscopic resection. Under present guidelines, endoscopic resection is considered definitive treatment if submucosal invasion is only superficial, but this is not routinely assessed. METHODS: Lymph node metastasis rates were determined for patient groups defined according to tumor pathological characteristics. Clinicopathological predictors of lymph node metastasis were determined by multivariable logistic regression and used to develop a nomogram in a randomly selected subset that was validated in the remainder. Overall survival was compared between Eastern and Western countries. RESULTS: Lymph node metastasis was found in 701 of 3166 (22.1%) Eastern and 153 of 560 (27.3%) Western patients. Independent predictors of lymph node metastasis were female sex, tumor size, distal stomach location, lymphovascular invasion, and moderate or poor differentiation. Patients fulfilling the National Comprehensive Cancer Network guideline criteria, excluding the requirement that invasion not extend beyond the superficial submucosa, had a lymph node metastasis rate of 8.9% (53/594). Excluding moderately differentiated tumors lowered the rate to 3.4% (10/296). The nomogram's area under the curve was 0.690. Regardless of lymph node status, overall survival was better in Eastern patients. CONCLUSIONS: The lymph node metastasis rate was lowest in patients with well differentiated tumors that were ≤3 cm and lacked lymphovascular invasion. These criteria may be useful in decisions regarding endoscopic resection as definitive treatment for pT1b gastric cancer.

Is Total Omentectomy Mandatory in T3 and T4a Gastric Cancer for Laparoscopic Distal Gastrectomy?

BACKGROUND: Despite the lack of strong evidence, total omentectomy (TO) remains the recommended procedure for gastric cancer (GC) for T3 or deeper tumors. Partial omentectomy (PO) has recently become a preferred procedure owing to its simplicity during laparoscopic distal gastrectomy (LDG); however, the oncological role of PO needs to be elucidated. METHODS: Overall, 341 patients with T3 or T4a GC who had undergone LDG between 2009 and 2016 were divided into TO (n = 167) and PO (n = 174) groups. Propensity matching was performed with respect to covariance age, sex, T and N stage, tumor size, and degree of tumor differentiation. Clinicopathological characteristics and long-term follow-up data were analyzed for both groups. RESULTS: After successful propensity matching, both groups included 107 patients. In a matched cohort, no significant difference in clinicopathologic features and short-term surgical outcomes was observed between the two groups. Furthermore, no significant difference in relapse-free survival (RFS; p = 0.201) and peritoneal seeding-free survival (PSFS; p = 0.094) was observed. However, tumor recurrence as peritoneal metastasis occurred in 5 (4.7%) patients in the PO group and 13 (12.1%) patients in the TO group. In Cox proportional hazards analysis, omentectomy was not identified as a significant factor for RFS, PSFS, and overall survival; however, advanced N and T4a stage were considered significant factors for RFS and PSFS, respectively. CONCLUSIONS: PO may be adopted during the LDG of T3 or T4a GC without definite gross serosal exposure. More large-scale evidence or prospective study is recommended.

Predictive model for long-term weight recovery after gastrectomy for gastric cancer: an introduction to a web calculator.

BACKGROUND: Weight changes after gastrectomy affect not only quality of life but also prognosis and survival. However, it remains challenging to predict the weight changes of individual patients. Using clinicopathological variables, we built a user-friendly tool to predict weight change after curative gastrectomy for gastric cancer. METHODS: The clinical data of 984 patients who underwent curative gastrectomy between 2009 and 2013 were retrospectively reviewed and analyzed. Multivariate logistic regression was performed to identify variables predictive of postoperative weight change. A nomogram was developed and verified via bootstrap resampling. RESULTS: Age, sex, performance status, body mass index, extent of resection, pathological stage, and postoperative weight change significantly influenced postoperative weight recovery. Postoperative levels of hemoglobin, albumin, ferritin and total iron-binding capacity were significant covariates. The nomogram performed well (concordance index = 0.637); calibration curves indicated appropriate levels of agreement. We developed an online weight prediction calculator based on the nomogram ( http://gc-weightchange.com/en/front/ ). CONCLUSIONS: The novel, Web-calculator based on the predictive model allows surgeons to explore patient weight patterns quickly. The model identifies patients at high risk for weight loss after gastrectomy; such patients require multidisciplinary medical support.

Effect of IL-10-producing B cells in peripheral blood and tumor tissue on gastric cancer.

BACKGROUND: Interleukin (IL)-10-producing B (B10) cells are generated in response to signals from the tumor microenvironment and promote tumor growth by interacting with B10 cells. We investigated the distributions of immune cells in peripheral blood and tumor tissue samples from patients with gastric cancer (GC). METHODS: Patients with GC who underwent radical gastrectomy in Seoul St. Mary's Hospital between August 2020 and May 2021 were enrolled in this study. Forty-two samples of peripheral blood were collected, and a pair of gastric mucosal samples (normal and cancerous mucosa; did not influence tumor diagnosis or staging) was collected from each patient after surgery. B10 cells in peripheral blood and cancer mucosa samples were investigated by flow cytometry and immunofluorescence. AGS cells, gastric cancer cell line, were cultured with IL-10 and measured cell death and cytokine secretion. Also, AGS cells were co-cultured with CD19 + B cells and measured cytokine secretion. RESULTS: The population of B10 cells was significantly larger in the blood of patients with GC compared with controls. In confocal images of gastric mucosal tissues, cancerous mucosa contained more B10 cells than normal mucosa. The population of B10 cells in cancerous mucosa increased with cancer stage. When AGS cells were cultured under cell-death conditions, cellular necrosis was significantly decreased, and proliferation was increased, for 1 day after IL-10 stimulation. Tumor necrosis factor (TNF)-α, IL-8, IL-1ß, and vascular endothelial growth factor secretion by cancer cells was significantly increased by coculture of AGS cells with GC-derived CD19+ B cells. CONCLUSIONS: B cells may be one of the populations that promote carcinogenesis by inducing the production of inflammatory mediators, such as IL-10, in GC. Targeting B10 cells activity could improve the outcomes of antitumor immunotherapy. Video Abstract.

Impact of postoperative NSAIDs (IV-PCA) use on short-term outcomes after laparoscopic gastrectomy for the patients of gastric cancer.

BACKGROUND: Further data are necessary to evaluate the risk of complications associated with the use of non-steroidal anti-inflammatory drugs (NSAIDs) postoperatively. This study aimed to determine the correlation between the use of NSAIDs in intravenous patient-controlled analgesia (IV-PCA) and postoperative complications after laparoscopic gastrectomy in patients with gastric cancer. METHODS: This retrospective, single-center study was conducted. The study population comprised 2150 patients who underwent laparoscopic gastrectomy for gastric cancer treatment. They were divided into two groups: non-NSAIDs (n = 1215) and NSAIDs (n = 935) according to their use of the drugs. Clinicopathologic characteristics, operative details, postoperative complications within 30 days, risk factors for complications, and survival were analyzed. RESULTS: Of the 2150 patients, 935 (43.49%) used NSAIDs. The overall complication rate showed no significant difference between the NSAIDs and non-NSAIDs groups (22.7% vs. 20.7%, p = 0.280), while the rates of anastomotic leakage and duodenal leakage were higher in the NSAID group (2.4% vs. 0.7%, p = 0.002 and 1.8% vs. 0.6%, p = 0.007, respectively). The rates of intra-abdominal bleeding and intra-abdominal abscess were significantly higher in the NSAID group (2.1% vs. 0.7%, p = 0.005 and 1.5% vs. 0.4%, p = 0.008, respectively). However, postoperative ileus occurred more frequently in the non-NSAID group (3.0% vs. 1.4%, p = 0.015). On multivariate analysis, NSAID use was an independent risk factor for early postoperative complications (1.303 [1.042-1.629], p = 0.020). Meanwhile, the NSAID group showed no differences in overall survival at each pathological stage. CONCLUSION: Postoperative NSAID use by IV-PCA is associated with anastomotic leakage, duodenal stump leakage, intra-abdominal bleeding, and intra-abdominal abscess in patients who underwent laparoscopic gastrectomy for gastric cancer. Caution is advised when NSAIDs are used peri-operatively.

Exploring ideal operative time for best outcomes in gastric cancer surgery: A multi-institutional study based on KLASS-07 database.

Objective: While a rushed operation can omit essential procedures, prolonged operative time results in higher morbidity. Nevertheless, the optimal operative time range remains uncertain. This study aimed to estimate the ideal operative time range and evaluate its applicability in laparoscopic cancer surgery. Methods: A prospectively collected multicenter database of 397 patients who underwent laparoscopic distal gastrectomy were retrospectively reviewed. The ideal operative time range was statistically calculated by separately analyzing the operative time of uneventful surgeries. Finally, intraoperative and postoperative outcomes were compared among the shorter, ideal, and longer operative time groups. Results: The statistically calculated ideal operative time was 135.4-165.4 min. The longer operative time (LOT) group had a lower rate of uneventful, perfect surgery than the ideal or shorter operative time (IOT/SOT) group (2.8% vs. 8.8% and 2.2% vs. 13.4%, all P<0.05). Longer operative time increased bleeding, postoperative morbidities, and delayed diet and discharge (all P<0.05). Particularly, an uneventful, perfect surgery could not be achieved when the operative time exceeded 240 min. Regardless of ideal time range, SOT group achieved the highest percentage of uneventful surgery (13.4%), which was possible by surgeon's ability to retrieve a higher number of lymph nodes and perform ≥150 gastrectomies annually. Conclusions: Operative time longer than the ideal time range (especially ≥240 min) should be avoided. If the essential operative procedure were faithfully conducted without compromising oncological safety, an operative time shorter than the ideal range leaded to a better prognosis. Efforts to minimize operative time should be attempted with sufficient surgical experience.

Combined high NEDD9 expression and E-cadherin loss correlate with poor clinical outcome in gastric cancer.

BACKGROUND AND AIM: Neural precursor cell expressed developmentally downregulated 9 (NEDD9) is a member of the Cas family. Previous studies have revealed that NEDD9 coordinates the focal adhesion kinase and Src signaling cascades that are involved in integrin-dependent adhesion and migration, invasion, cell apoptosis and life cycle, and survival, which may play a role in epithelial-mesenchymal transformation. The aim of this study was to analyze the expression of NEDD9 and E-cadherin in gastric cancer (GC) and evaluate their clinical significance. METHODS: NEDD9 and E-cadherin expression was analyzed with immunohistochemistry using tissue microarray technique in 435 GC patients who underwent gastrectomy. The NEDD9 expression level was defined by the combination score, which was determined by multiplying the staining intensity score and the proportion score (≥5; NEDD9-high, <5; NEDD9-low). E-cadherin loss was defined as a total loss of staining. The clinicopathologic parameters, overall survival, and disease-free survival rates were analyzed according to the NEDD9 and E-cadherin expression status. RESULTS: The combined NEDD9 and E-cadherin expression status correlated with lymphatic invasion (P = 0.001), vascular invasion (P = 0.020), and T stage (P = 0.001). Combined high NEDD9 expression and loss of E-cadherin expression status had a worse overall survival rate (P < 0.001) and served as a poor prognostic factor (Hazard ratio 2.49, 95% CI 1.25-5, P = 0.01). CONCLUSIONS: Immunohistochemical staining for NEDD9 and E-cadherin may function as a candidate prognostic marker for gastric cancer in everyday practice, especially when applied in combination.

The First Systematic Gastroscopy Training Program for Surgeons in Korea.

BACKGROUND: Endoscopic evaluation of the stomach is essential for preoperative planning and post-surgical surveillance for various diseases of the stomach, including malignancy. The gastroscopy education program for surgeons is currently in its infancy and is not systematically organized in Korea. This study aimed to introduce the first systematic gastroscopy education program for surgeons in Korea. METHODS: The gastroscopy education program entitled "Gastroscopy School for Surgeons (GSS)" comprised of theoretical education, dry lab hands-on training, and clinical practice. All participants were beginners without any gastroscopy experience. Clinical practice started after the completion of the theoretical and dry lab training. The gastroscopy practices utilized simple luminal observation, biopsy, localization using clips or dye injection, and limited therapeutic gastroscopy. The educational performances and surveys from 33 participants were analyzed. RESULTS: The participants consisted of surgical residents, general surgeons, gastrointestinal-specialized surgeons, and physicians. Participants performed a total of 2,272 gastroscopies, 2,008 of which were post-gastrectomy cases. Currently, of the 33 participants, 7 (21.2%) of the participants performed gastroscopy regularly, and 7 (21.2%) occasionally. According to the self-reported survey, one participant assessed their current gastroscopic technique to be at the expert level, and 25 (75.8%) at a proficient level. All participants considered gastroscopy education for surgeons to be necessary, and 28 (84.8%) stated that systematic education is not currently provided in Korea. CONCLUSION: We introduced the first systematic gastroscopy education program for surgeons in Korea, namely the GSS, which is practical and meets clinical needs. More training centers are needed to expand gastroscopy training among Korean surgeons.

Trends in laparoscopic anti-reflux surgery: a Korea nationwide study.

BACKGROUND: In 2014, the results derived from the nationwide data of the Korean Anti-reflux Surgery Study (KARS) demonstrated short-term feasibility and safety of anti-reflux surgery. This study aimed to update the longer-term safety and feasibility of laparoscopic anti-reflux surgery up to 1-year follow-up with the KARS nationwide cohort. METHODS: The data of 310 patients with GERD who received anti-reflux surgery up to 2018 were analyzed. Baseline patient characteristics, postoperative symptom resolution, and postoperative complications were evaluated at postoperative 3 months and 1 year using the questionnaire designed by KARS. We divided the patients into two groups according to the operation period (up to and after 2014) to identify changes in the trends of the characteristics of surgical patients and operative qualities. RESULTS: The typical preoperative symptoms were present in 275 patients (91.7%), and atypical symptoms were present in 208 patients (71.0%). Ninety-seven (35.5%) and 124 patients (46.1%) had inadequate PPI responses and hiatal hernia, respectively. At postoperative 1 year, typical and atypical symptoms were either completely or partially controlled in 90.3% and 73.5.0% of patients, respectively. Moderate-to-severe dysphagia, inability to belch, gas bloating, and flatulence at postoperative 1 year were identified in 23.5%, 29.4%, 23.2%, and 22.0% of patients, respectively. The number of surgical patients continuously increased from 2011 to 2018 in Korea. The proportion of patients with hiatal hernia and comorbidities increased (p < 0.01, p = 0.053), and the operation time decreased significantly (p < 0.01) in the late period (2015-2018) as compared with the early period (2011-2014). Symptom control and complication rate were equivalent between the two periods. CONCLUSIONS: Anti-reflux surgery was effective with > 90% of typical symptom resolution and posed a comparable postoperative complication rate with those in Western studies with mid-term to long-term follow-up. This result supports the feasibility and safety of anti-reflux surgery as a treatment for GERD in the Korean population.

Negative Impact of Endoscopic Submucosal Dissection on Short-Term Surgical Outcomes of Subsequent Laparoscopic Distal Gastrectomy for Gastric Cancer.

BACKGROUND: Endoscopic submucosal dissection (ESD) for gastric cancer produces an artificial ulcer, and negative effects on the surgical outcomes of additional gastrectomy after ESD are anticipated. The aim of this study is to analyze the effect of ESD on subsequent laparoscopic radical gastrectomy procedures and to compare the surgical results of post-ESD patients with the control group using propensity score (PS) methods. PATIENTS AND METHODS: From 2013 to 2018, 1446 patients underwent totally laparoscopic distal gastrectomy in our center. Among these patients, the clinicopathological factors and short-term surgical outcomes of 107 patients who underwent ESD before surgery (the ESD group) were evaluated. A 1:4 PS matching and inverse probability weighting method was utilized to compare the short-term surgical outcomes of the ESD group with those of a matched control group. RESULTS: A longer operation time was required for the patients who underwent gastrectomy earlier than 24 days after ESD than for the patients who did not. Patients whose ulcer size, due to previous ESD, exceeded 4.6 cm required longer operation times and exhibited more intraoperative blood loss than patients whose ulcer size was small. In the PS matching analysis, patients who underwent distal gastrectomy within 24 days after ESD showed more frequent postoperative morbidity than non-ESD patients. CONCLUSIONS: ESD after laparoscopic distal gastrectomy is largely safe in terms of short-term surgical outcomes, but a short interval between the two procedures and a large ESD scar can make subsequent operation difficult.

The preoperative and the postoperative neutrophil-to-lymphocyte ratios both predict prognosis in gastric cancer patients.

BACKGROUND: Both the preoperative and postoperative neutrophil-to-lymphocyte ratios (NLRs) have been proposed to predict the long-term prognosis in some cancers, including gastric cancer. The present study investigated the prognostic impact of postoperative NLR, and its preoperative to postoperative changes, in patients with gastric cancer. METHODS: From 2009 to 2012, 1227 consecutive patients who underwent curative surgery for gastric cancer were enrolled in this study. The optimal cut-off value for the postoperative 6-month NLR was 1.7, as determined by receiver operating characteristic curve analysis. Patients were categorized into low- and high-NLR groups based on their postoperative NLR. Four additional groups (low to low, low to high, high to low, and high to high groups) were defined based on the preoperative to postoperative change in the NLR. RESULTS: The 5-year overall survival (OS) rates of the low- and high-NLR group were 90.7% and 83.0%, respectively (P < 0.001). The differences in OS were significant in stage I and stage III gastric cancer patients (P< 0.001 and 0.012, respectively). Postoperative NLR was an independent prognostic factor for OS (hazard ratio [HR] = 1.556; P = 0.010). The high to high NLR change was a significant predictor of OS (HR = 1.817; P = 0.003). CONCLUSIONS: High preoperative and postoperative NLRs, and especially the persistent elevation of preoperative to postoperative NLR, were significant poor prognostic factors for OS in patients with gastric cancer.

Efficacy of capecitabine and oxaliplatin versus S-1 as adjuvant chemotherapy in gastric cancer after D2 lymph node dissection according to lymph node ratio and N stage.

BACKGROUND: We sought to assess the prognostic significance of lymph node ratio (LNR) and N stage in patients undergoing D2 gastrectomy and adjuvant chemotherapy, S-1, and XELOX and to compare the efficacy of them according to LNRs and N stages to evaluate the clinical impact of using LNRs compared with using N staging. METHODS: Patients undergoing D2 gastrectomy with adequate lymph node dissection and adjuvant chemotherapy for stage II/III gastric cancer between Mar 2011 and Dec 2016 were analysed. Of the 477 patients enrolled, 331 received S-1 and 146 received XELOX. LNR groups were segregated as 0, 0-0.1, 0.1-0.25, and > 0.25 (LNR0, 1, 2, and 3, respectively). Propensity score matching (PSM) was used to minimise potential selection bias and compare DFS and OS stratified by LNRs and N stages in the two treatment groups. RESULTS: After PSM, the sample size of each group was 110 patients, and variables were well balanced. All patients had more than 15 examined lymph nodes (median 51, range 16~124). In multivariate analysis, LNR (> 0.25) and N stage (N3) showed independent prognostic value in OS and DFS, but LNR (> 0.25) showed better prognostic value. In subgroup analysis, the LNR3 group showed better 5-year DFS (20% vs 54%; HR 0.29; p = 0.004) and 5-year OS (26% vs 67%; HR 0.28; p = 0.020) in the XELOX group. The N3 group showed better 5-year DFS (38% vs 66%; HR 0.40; p = 0.004) and 5-year OS (47% vs 71%; HR 0.45; p = 0.019) in the XELOX group. Stage IIIC showed better 5-year DFS (22% vs 57%; HR 0.32; p = 0.004) and 5-year OS (27% vs 68%; HR 0.32; p = 0.009) in the XELOX group. The LNR3 group within N3 patients showed better 5-year DFS (21% vs 55%; HR 0.31; p = 0.004) and 5-year OS (27% vs 68%; HR 0.34; p = 0.018) in the XELOX group. CONCLUSIONS: LNR showed better prognostic value than N staging. LNR3, N3 and stage IIIC groups showed the superior efficacy of XELOX to that of S-1. And the LNR3 group within N3 patients showed more survival benefit from XELOX. LNR > 0.25, N3 stage and stage IIIC were the discriminant factors for selecting XELOX over S-1. TRIAL REGISTRATION: Not applicable (retrospective study).

Mixed Histology Is a Risk Factor for Lymph Node Metastasis in Early Gastric Cancer.

BACKGROUND: The risk factors of lymph node (LN) metastasis are important factors to consider in endoscopic submucosal dissection in early gastric cancer (EGC). The aim of the study was to identify the correlation between mixed histology and LN metastasis in EGC. METHODS: A total of 1645 patients who underwent curative radical gastrectomy for EGC were divided into three groups (pure differentiated [pure D], mixed, and pure undifferentiated [pure UD]) according to histologic type. They were subsequently analyzed retrospectively for LN metastasis. The patients who had mixed histology between differentiated and undifferentiated tubular adenocarcinoma were defined as mixed group. RESULTS: The pure UD group was significantly younger than the other groups. Tumor size was larger in the mixed group. LN metastasis occurred more frequently in the mixed group and the pure UD group than in the pure D group (pure D, mixed, and pure UD, 7.7%, 23.2%, and 10.8%, respectively; P < 0.001). A logistic regression analysis revealed that the independent risk factors for LN metastasis were large tumor size (odd ratio [OR], 1.308), submucosal invasion (OR, 3.565), lymphovascular invasion (OR, 9.755), and histologic types of mixed (OR, 2.360) and pure UD (OR, 1.657). CONCLUSIONS: Mixed histology is an important risk factor for LN metastasis in EGC. Thus, radical gastrectomy should be considered in the cases of mixed-type histology after endoscopic resection.

Nature versus nurture: the impact of nativity and site of treatment on survival for gastric cancer.

BACKGROUND: The prognosis of gastric cancer patients is better in Asia than in the West. Genetic, environmental, and treatment factors have all been implicated. We sought to explore the extent to which the place of birth and the place of treatment influences survival outcomes in Korean and US patients with localized gastric cancer. METHODS: Patients with localized gastric adenocarcinoma undergoing potentially curative gastrectomy from 1989 to 2010 were identified from the SEER registry and two single institution databases from the US and Korea. Patients were categorized into three groups: Koreans born/treated in Korea (KK), Koreans born in Korea/treated in the US (KUS), and White Americans born/treated in the US (W), and disease-specific survival rates compared. RESULTS: We identified 16,622 patients: 3,984 (24.0%) KK, 1,046 (6.3%) KUS, and 11,592 (69.7%) W patients. KK patients had longer unadjusted median (not reached) and 5-year disease-specific survival (81.6%) rates than KUS (87 months, 55.9%) and W (35 months, 39.2%; p < 0.001 for all comparisons) patients. This finding persisted on subset analyses of patients with stage IA tumors, without cardia/GEJ tumors, with > 15 examined lymph nodes, and treated at a US center of excellence. On multivariable analysis, KUS (HR 2.80, p < 0.001) and W (HR 5.79, p < 0.001) patients had an increased risk of mortality compared to KK patients. CONCLUSIONS: Both the place of birth and the place of treatment significantly contribute to the improved prognosis of patients with gastric cancer in Korea relative to those in the US, implicating both nature and nurture in this phenomenon.

Acid Secretion and Its Relationship to Esophageal Reflux Symptom in Patients with Subtotal Gastrectomy.

BACKGROUND: Esophageal reflux symptom has been reported as common in patients with subtotal gastrectomy. Management of postoperative esophageal reflux symptom is not satisfactory. The aim of this study is to investigate prevalence of esophageal reflux symptom after subtotal gastrectomy and assess factors affecting esophageal reflux symptom in subtotal gastrectomy patients. METHODS: We prospectively enrolled 100 consecutive patients with subtotal gastrectomy who were regularly followed up by endoscopic examination. Acid secretory capacity was assessed by measuring messenger RNA (mRNA) expression of H+/K+-adenosine triphosphatase (ATPase) via real-time polymerase chain reaction (PCR) in biopsy specimens. RESULTS: In total, 47 % of patients had typical esophageal reflux symptom, where heartburn or regurgitation was experienced at least weekly. Age, sex, body mass index, and type of reconstruction did not differ between esophageal reflux and non-esophageal-reflux groups. The esophageal reflux group had longer duration from time of operation until study (median 5.0 versus 3.6 years; P = 0.017). Hill grade for gastroesophageal (GE) flap valve was higher in the esophageal reflux group than in the non-esophageal-reflux group (P = 0.027). H+/K+-ATPase mRNA expression was higher in the esophageal reflux group than in the non-esophageal-reflux group [3967.6 (± 7583.7) versus 896.2 (± 1456.0); P = 0.006]. Multivariate analysis revealed that postoperative duration, H+/K+-ATPase mRNA expression level, and GE flap valve disruption were significantly associated with esophageal reflux symptom development. CONCLUSIONS: Esophageal reflux symptom is common in patients after subtotal gastrectomy, possibly because of anti-reflux-barrier impairment and preservation of acid secretory capacity following surgery. Optimal acid suppression may be helpful in managing postoperative esophageal reflux symptom.

Splenic Infarction as a Delayed Febrile Complication Following Radical Gastrectomy for Gastric Cancer Patients: Computed Tomography-Based Analysis.

BACKGROUND: The aim of this study was to evaluate the incidence and clinical characteristics of splenic infarction (SI) in gastric cancer patients who have undergone gastrectomy. METHODS: For this study, the medical records of 1084 patients were reviewed and 877 patients were ultimately enrolled. The times of symptom onset, diagnosis of SI, and complete resolution on CT were calculated from the day of the operation. Based on the wedge shape of the SI in all cases, the total volume of the SI was measured based on that of a corn kernel. RESULTS: Thirty-six patients (4.10%) were diagnosed with SI after gastrectomy; four of these patients (0.45%) developed complications associated with the SI. Total gastrectomy and extended lymph node dissection were risk factors for development of SI. Patients with complications exhibited inflammatory signs between 7 and 10 days after surgery. The mean volume of the SI was 4025.69 mm3. The mean time to complete resolution on the CT scan was 327 days postoperatively. In 30 cases, small branched arteries from the splenic artery that could have caused the SI were retrospectively detected on the preoperative CT scans. CONCLUSION: Although the incidence of the SI was low, large volume of the SI is associated with complication development. Measuring the infarction volume via a CT scan may be useful to decide on the treatment strategy. Preoperative 3-D reconstruction of the splenic artery tributaries may help reduce the risk of inadvertent SI.

Radical Gastrectomy After Chemotherapy May Prolong Survival in Stage IV Gastric Cancer: A Korean Multi-institutional Analysis.

ABASTRACT: BACKGROUND: Despite the development of newer treatments, the prognosis for patients with stage IV gastric cancer remains grave. This study evaluated the efficacy of gastrectomy following response to chemotherapy in patients with stage IV gastric cancer. METHODS: A total of 419 patients who were diagnosed with stage IV gastric cancer were identified from the multi-institutional Catholic Gastric Cancer Study Group database. The patients were divided into four groups: 212 were in the chemotherapy only (CTx) group, 124 were in the chemotherapy after palliative gastrectomy (G-CTx) group, 23 were in the radical gastrectomy after chemotherapy (CTx-G) group, and 60 were in the best supportive care group. To compensate for the effects of chemotherapy, cases of chemotherapy responsive were analyzed separately. To identify factors affecting survival rates, cure rates for surgery in the surgery group were analyzed. RESULTS: The 3-year survival rate of the CTx-G group was significantly higher than that of the CTx group (42.8 vs. 12.0%, p = 0.001). Moreover, the CTx-G group's 3-year survival rate was greater than that of the G-CTx group (42.8 vs. 37.1%, p = 0.207). Chemotherapy-responsive patients in the CTx-G group had a better 3-year survival rate than those in the G-CTx group (46.1 vs. 18.4%, respectively, p = 0.011). In the surgery group, R0 resection led to a significantly better 3-year survival rate than palliative gastrectomy (61.1 vs. 16.2%, p = 0.003). CONCLUSIONS: Adjuvant surgery might improve the survival rate of patients with stage IV gastric cancer, particularly in R0 resection cases.

Radiofrequency ablation for liver metastases in patients with gastric cancer as an alternative to hepatic resection.

BACKGROUND: The purpose of this retrospective study was to determine whether RFA could provide an alternative treatment modality for selected patients who are not candidates for hepatic resection. METHODS: A total of 18 consecutive patients with liver metastases alone from gastric cancer treated with radiofrequency ablation (RFA, n = 11) or hepatic resection (HR, n = 7) at Seoul St. Mary's Hospital, Korea, between January 2000 and September 2014, were enrolled. RESULTS: The median OS and DFS in the RFA group were 40.5 ± 22.3 and 10.3 ± 1.07 months, respectively. There was no significant difference between the RFA and HR groups in terms of baseline characteristics except for performance status. Mean survival and DFS times of all patients were 60.1 ± 9.4 and 40.9 ± 10.2 months, respectively. Mean OS times in the HR and RFA groups were 67.5 ± 15.4 and 51.1 ± 9.8 months (P = 0.671), respectively, and the mean DFS time in the HR group (74.1 ± 14.2 months) was longer than that in the RFA group (26.9 ± 9.2 months), but the difference was not significant (P = 0.076). CONCLUSIONS: In patients who are not candidates for surgical treatment, RFA may be an alternative to HR.