The long-term quality of life after distal and pylorus-preserving gastrectomy for stage I gastric cancer: A prospective multi-institutional study (CCOG1601).

PURPOSE: While regarded as function-preserving gastrectomy, few prospective longitudinal clinical trials have addressed the postoperative quality of life (QOL) after pylorus-preserving gastrectomy (PPG). We prospectively compared chronological changes in postoperative body weight and the QOL between PPG and distal gastrectomy (DG) for pathological Stage I gastric cancer (GC). METHODS: We conducted a multi-institutional prospective study (CCOG1601) to evaluate patients who underwent DG and PPG. The QOL was examined using the European Organization for Research and Treatment of Cancer Quality of life questionnaire-C30 (EORTC QLQ-C30) and the Post-Gastrectomy Syndrome Assessment Scale-37 (PGSAS-37). A total of 295 patients were enrolled from 15 institutions, and propensity score matching was performed to adjust for the essential variables for comparison analyses. RESULTS: After propensity score matching, 25 pairs of patients were identified. In the first postoperative month, DG achieved a superior nausea and vomiting score (EORTC QLQ-C30) and meal-related distress, indigestion, and dumping scores (PGSAS-37). No significant differences were noted between DG and PPG in the long-term QOL. Postoperative body weight loss was similar in both groups. CONCLUSIONS: This prospective observational study failed to demonstrate the superiority of PPG over DG in terms of postoperative body weight changes and the QOL.

Protocol of a phase II study investigating the efficacy and safety of trifluridine/tipiracil plus ramucirumab as a third-line or later treatment for advanced gastric cancer.

In Japan, systemic chemotherapy is the standard treatment for unresectable, advanced, or recurrent gastric cancer. However, numerous patients with gastric cancer do not receive late-line treatment because of the rapid progression of gastric cancer. Additionally, late-line treatments, such as nivolumab, trifluridine tipiracil (FTD/TPI), or irinotecan, have limited effects on improving clinical symptoms and delaying the onset of symptoms associated with cancer progression. Recently, a combination of FTD/TPI and ramucirumab was reported to have a high response rate in late-line treatment; however, owing to patient selection bias and a high rate of hematologic toxicity in that previous study, this regimen may not be feasible in real-world clinical applications. Our objective is to conduct a single-arm phase II study to assess the safety and efficacy of FTD/TPI plus ramucirumab combination therapy for gastric cancer after third-line treatment under real-world clinical conditions. This study will recruit 32 patients according to eligibility criteria and administer FTD/TPI (35 mg/m2) and intravenous ramucirumab (8 mg/kg). The primary endpoint will be the time to treatment failure. The secondary endpoints will include the overall survival time, progression-free survival time, overall response rate, disease control rate, relative dose intensity, and incidence of adverse events. The results will add new insights for improving the late-line treatment of advanced gastric cancer.

Proposal of the Second Cutoff of Serum Carcinoembryonic Antigen Levels to Stratify Patients into Low, Intermediate, and High Risks at Recurrences after Curative Resection of Gastric Cancer.

INTRODUCTION: Carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 are widely used for treating various cancers, with cutoff values of 5.0 ng/mL and 37.0 IU/mL, respectively. However, these cutoff values are not for specific diseases or purposes but are uniformly used for any disease and any purpose. It is also unclear as to whether patients are at equal risk of recurrence if they are below the cutoff values. This study aimed to investigate the optimal cutoff of serum tumor markers in the stratification of recurrence risk after curative resection of gastric cancer. METHODS: We constructed a nine-center integrated database of patients who received gastrectomy between January 2010 and December 2014 with a 5-year follow-up period. We determined the cutoff value of preoperative serum tumor marker levels correlated with postoperative recurrences and evaluated its performance in risk stratification for recurrences in 948 patients with stage II/III gastric cancer who underwent radical resection. RESULTS: The hazard ratio for postoperative recurrences increased at two points of preoperative CEA levels, 3.6 ng/mL and 5.0 ng/mL, which were set as cutoffs. These two cutoffs stratified relapse-free survival into three levels. CONCLUSIONS: By adding a second cutoff value for preoperative serum CEA, which was proposed specifically for the prediction of recurrences, patients can be stratified into low-, intermediate-, and high-risk recurrences after curative resection of gastric cancer.

Modified Albumin-Bilirubin Grade optimized for risk stratification of patients with stage II-III gastric cancer.

PURPOSE: The albumin-bilirubin (ALBI) grade is calculated using albumin and bilirubin values. We determined the optimal cutoff value of the ALBI grade for predicting the postoperative prognosis of gastric cancer (GC). METHODS: We retrospectively reviewed a multicenter database of 3571 patients who underwent gastrectomy for GC between January 2010 and December 2014. The modified ALBI (mALBI) grade was determined using cutoff values: grade 1 (mALBI ≤ - 2.70), 2 (mALBI - 2.70 to - 2.10), and 3 (mALBI > - 2.10). We used a validation cohort to evaluate reproducibility. RESULTS: The entire cohort (n = 956) was randomly assigned to the learning or validation cohorts (n = 478 each). The former was categorized into the following groups by the preoperative mALBI grade: grade 1 (n = 235), grade 2 (n = 162), and grade 3 (n = 81). The disease-specific survival (DSS) rates of the learning and validation cohorts were significantly shortened in association with higher mALBI grade (learning, p = 0.0068; validation, p = 0.0100). A multivariate analysis revealed that mALBI grade 3 served as an independent prognostic factor for DSS. Furthermore, mALBI grade 2 or 3 was associated with a greater risk of disease-specific death in most subgroups. CONCLUSION: The mALBI grade accurately predicted the long-term postoperative prognosis of locally advanced GC.

Preoperative neutrophil-to-platelet ratio as a potential prognostic factor for gastric cancer with positive peritoneal lavage cytology in the absence of other non-curative factors: a multi-institutional dataset analysis.

PURPOSE: Peritoneal dissemination is the key to the prognosis of gastric cancer (GC) and can be detected early with peritoneal lavage cytology. No studies have examined preoperative prognostic factors in GC patients who have positive cytology but no other non-curative factors. METHODS: We conducted a retrospective analysis using a multicenter database of 3575 patients who underwent gastrectomy between 2010 and 2014. Patients with positive peritoneal lavage cytology as a sole non-curative factor were retrieved, and correlations between parameters and the prognosis were compared. RESULTS: A total of 66 patients were identified as eligible. In the receiver operating characteristic (ROC) curve analysis, the neutrophil-to-platelet ratio (NPR) had the greatest area under the curve value and was selected. We divided the NPR into two groups based on the optimal cutoff value of the NPR (2.000), as determined by the ROC curve analysis. A high preoperative NPR was the only prognostic factor. The NPR-high group had shorter overall survival than the NPR-low group (hazard ratio 1.85, 95% confidence interval 1.05-3.28, P = 0.032). CONCLUSION: Our analysis indicated that the preoperative NPR serves as a prognostic factor in GC patients with positive peritoneal lavage cytology in the absence of other non-curative factors.

Risk score for predicting death from other causes after curative gastrectomy for gastric cancer.

BACKGROUND: The number of patients who die from causes other than gastric cancer after R0 resection is increasing in Japan, due in part to the aging population. However, few studies have comprehensively investigated the clinicopathological risks associated with deaths from other causes after gastrectomy. This study aimed to build a risk score for predicting such deaths. METHODS: We retrospectively reviewed clinical data for 3575 patients who underwent gastrectomy for gastric cancer at nine institutions in Japan between January 2010 and December 2014. RESULTS: The final study population of 1758 patients were assigned to Group A (n = 187): patients who died from other causes within 5 years of surgery, and Group B (n = 1571): patients who survived ≥ 5 years after surgery. Multivariate analysis identified nine characteristics as risk factors for poor survival: age ≥ 75 years, male sex, body mass index < 22 kg/m2, Eastern Cooperative Oncology Group Performance Status (≥ 1), diabetes mellitus, cardiovascular/cerebrovascular disease, other malignant diseases, preoperative albumin level < 3.5 g/dL, and total gastrectomy. Patients with risk scores of 0-2, 3-4, or 5-9 (based on 1 point per characteristics) were classified into Low-risk, Intermediate-risk, and High-risk groups, respectively. The 5-year survival rates were 96.5%, 85.3%, and 56.5%, for the Low-, Intermediate-, and High-risk groups, respectively, and the hazard ratio (95% confidence intervals) was 16.33 (10.85-24.58, p < 0.001) for the High-risk group. CONCLUSIONS: The risk score defined here may be useful for predicting deaths from other causes after curative gastrectomy.

Prognostic impact of a microscopic positive margin in patients undergoing gastrectomy for gastric cancer: a propensity score­matched analysis of a multi­institutional dataset.

PURPOSE: We analyzed the effect of a microscopic positive margin on survival outcomes after gastrectomy for gastric cancer METHODS: We analyzed a multi-institutional dataset to study patients who underwent gastrectomy with curative intent between 2010 and 2014. We used propensity score matching to strictly balance the patients' oncological features, backgrounds, and postoperative treatment to compare the survival outcomes of those with microscopic positive margins and those with negative margins. RESULTS: Among 3029 patients, 32 (1.1%) had positive margins. After matching, we enrolled 128 patients in this retrospective analysis: 32 with a positive margin and 96 with a negative margin. The recurrence-free survival of the positive-margin group was significantly shorter than that of the negative-margin group (hazard ratio [HR], 1.62, 95% confidence interval, 1.00-2.63, p = 0.0485). Consistent results were observed for patients with pStages I-III disease (HR, 1.65, p = 0.0835), whereas the survival curves overlapped in those with pStage IV disease (HR, 1.29, p = 0.5934). The prevalence of overall recurrence in the positive-margin group was higher than that in the negative-margin group (75% vs 58%, p = 0.0917). This trend was consistent with locoregional recurrence (9% vs 3%) and distant recurrence (69% vs 55%). CONCLUSIONS: The survival of patients after curative gastrectomy for gastric cancer was worse in those with microscopic positive margins than in those with negative margins.

E-PASS scoring system serves as a predictor of short- and long-term outcomes in gastric cancer surgery.

PURPOSES: This study aimed to evaluate the estimation of the physiological ability and surgical stress (E-PASS) scoring system for predicting the short- and long-term outcomes in gastric cancer (GC) surgery. METHODS: We analyzed a multi-institutional dataset to study patients who underwent gastrectomy with a curative intent between 2010 and 2014. This study evaluated the associations between the optimal E-PASS score cutoff value and the following outcomes: (1) the incidence of postoperative complications in stage I-III GC patients and (2) the prognosis in stage II-III GC patients. RESULTS: A total of 2495 GC patients were included. A cutoff value of 0.419 was determined using the ROC curve analysis. Postoperative complications were observed more frequently in the E-PASS-high group than that in the E-PASS-low group (30% vs. 17%, p < 0.0001). Among pStage II-III GC patients (n = 1009), the overall survival time of the E-PASS-high group was significantly shorter than that of the E-PASS-low group (hazard ratio 2.08; 95% confidence interval 1.64-2.65; p < 0.0001). A forest plot revealed that E-PASS-high was associated with a greater prognostic factor for overall survival in most subgroups. CONCLUSIONS: The E-PASS scoring system may therefore be a useful predictor of the short- and long-term outcomes in patients with GC who have undergone radical gastrectomy.

Efficacy of Splenectomy for Proximal Gastric Cancer with Greater Curvature Invasion or Type 4 Tumor: a Propensity Score Analysis of a Multi-Institutional Dataset.

BACKGROUND: Splenectomy for proximal gastric cancer was found to have no survival benefit in a randomized trial clarifying the role of splenectomy (JCOG0110 study). However, since tumor with invasion to the greater curvature and Type 4 tumor were excluded in JCOG0110, the benefit of splenectomy for these tumors is not known. METHODS: A multicenter dataset of patients with gastric cancer who underwent gastrectomy between 2010 and 2014 was created. From the dataset, 114 eligible patients with proximal advanced gastric cancer with invasion to the greater curvature or Type 4 tumor were enrolled. There were 60 patients in the gastrectomy with splenectomy (Spx) group and 54 patients in the spleen-preserving (Prs) group. To balance the essential variables, propensity score analysis was performed, estimating the propensity score with a logistic regression model. Adjusted overall survival (OS) and adjusted disease-free survival (DFS) were estimated using the inverse probability of treatment weighting (IPTW) method. RESULTS: There were significant differences in age, performance status, comorbidity, macroscopic type, and clinical T stage between the Spx and Prs groups. The model for estimating the propensity score was well adapted (c-statistic: 0.830, 95%CI: 0.754-0.906). Adjusted OS was identical between the two groups (HR = 1.089, 95%CI: 0.759-1.563; p = 0.644). The DFS curve of Prs group was consistently tended to be lower than Spx, but the difference was not significant (HR = 0.813, 95%CI: 0.572-1.156; p = 0.249). CONCLUSIONS: The efficacy of splenectomy was minimal for proximal advanced gastric cancer even with invasion to the greater curvature or Type 4 tumor.

Accurate Prediction of Prognosis After Radical Resection of Gastric Cancer by the Modified Systemic Inflammation Score; a Multicenter Dataset Analysis.

BACKGROUND: The presence of chronic inflammation and nutritional status in cancer patients affects its prognosis. There is a clinical need for a prognostic predictor that is objective and accurate, and that can be easily evaluated by preoperative screening. We evaluated the importance and usefulness of the preoperative modified systemic inflammation score (mSIS) to predict the long-term outcome of patients undergoing curative resection for gastric cancer (GC). METHODS: Of the 3571 patients who underwent curative resection for GC in nine institutions between January 2010 and December 2014, 1764 patients who met the inclusion criteria were included. The mSIS was formulated according to the serum albumin level (ALB) and lymphocyte-to-monocyte ratio (LMR) as follows: mSIS 0 (ALB ≥ 4.0 g/dL and LMR ≥ 3.4), mSIS 1 (ALB < 4.0 g/dL or LMR < 3.4), and mSIS 2 (ALB < 4.0 g/dL and LMR < 3.4). RESULTS: Patients were categorized into preoperative mSIS 0 (n = 955), mSIS 1 (n = 584), and mSIS 2 (n = 225) groups. The overall survival times and the disease-free survival times of patients in preoperative mSIS 0,1 and 2 sequentially shortened (P < 0.0001), and mSIS 1 and 2 were identified as an independent prognostic factor (hazard ratio [HR] 1.35, 95% confidence interval [CI] 1.06-1.272, P = 0.0125 and HR 1.63, 95% CI 1.21-2.19, P = 0.0012). A stepwise increase in the prevalence of hematogenous recurrences was directly proportional to the mSIS. A forest plot revealed that mSIS 0,1 was associated with a greater risk of overall survival in most subgroups. CONCLUSION: Preoperative mSIS can be easily calculated, and it is suggested that it is useful as a prognostic predictor of patients with different disease stages, for stratifying and evaluating clinical outcomes.

Safety and efficacy of S-1 plus oxaliplatin 130 mg/m2 combination therapy in patients with previously untreated HER2-negative unresectable, advanced, or recurrent gastric/gastroesophageal junction cancer: a phase II trial (KSCC1501A).

BACKGROUND: In a randomized pivotal global phase III study, S-1 and oxaliplatin 100 mg/m2 (SOX100) combination chemotherapy was as effective as S-1 and cisplatin for advanced gastric cancer (AGC) and showed a favorable safety profile. In this phase II study, we analyzed survival outcomes to assess the efficacy and safety of the SOX regimen with oxaliplatin 130 mg/m2 (SOX130) in AGC. METHODS: Patients with HER2-negative AGC received 80 mg/m2/day S-1 orally on days 1-14 and 130 mg/m2 oxaliplatin intravenously on day 1 of each 21-day cycle until the criteria for treatment withdrawal were fulfilled. The primary endpoint was the response rate (RR), and the null hypothesis of RR in the current trial was 45%. The secondary endpoints were progression-free survival (PFS) and overall survival (OS). Adverse events (AEs) were recorded according to CTCAE version 4.0. RESULTS: Seventy-one patients were enrolled from June 2015 to November 2016, but eight were excluded for ineligibility. Therefore, all final analyses were conducted with 63 patients. The confirmed RR was 46.0% (90% confidence interval [CI]: 36.1-56.3), and the disease control rate was 77.8% (90% CI: 68.1-85.1). The median PFS and OS were 4.9 (95% CI: 4.2-7.1) and 14.8 (95% CI: 11.1-18.9) months, respectively. Incidences of grade 3-4 AEs > 10% were anorexia (19.0%), peripheral neuropathy (12.7%), nausea (11.1%), and thrombocytopenia (11.1%). CONCLUSIONS: This study represents the first evaluation of SOX130 in patients with HER2-negative AGC. SOX130 showed an acceptable safety profile, but the prespecified statistical efficacy targets were not achieved.

Short-term outcomes of gastrectomy after neoadjuvant chemotherapy for clinical stage III gastric cancer: propensity score-matched analysis of a multi-institutional database.

PURPOSE: Preoperative chemotherapy for gastric cancer may be effective from the standpoint of compliance, although there is insufficient evidence of its efficacy. We analyzed a multicenter database to clarify whether preoperative chemotherapy influenced the short-term outcomes of gastrectomy. METHODS: We analyzed, retrospectively, 3571 patients who underwent gastrectomy between January, 2010 and December, 2014. Patients with clinical stage-III gastric adenocarcinoma were divided into a neoadjuvant chemotherapy (NAC) group and a non-NAC group. We performed propensity-matched comparative analysis to stratify the groups according to age, sex, tumor region, tumor type, preoperative stage, procedure, lymph node dissection, and tumor differentiation. Preoperative blood data, surgical findings, and postoperative complications were analyzed. RESULTS: Analysis of the matched NAC (n = 64) and non-NAC (n = 128) groups revealed that the preoperative values of neutrophils, platelets, and Hb were significantly lower in the NAC group. Blood loss during surgery was significantly higher, surgical times were longer, and the rate of repeat surgery was significantly lower in the NAC group; however, the rates of rehospitalization did not differ between the groups and mortality was 0% in both groups. Postoperative complications were not significantly different between the groups. CONCLUSIONS: NAC did not increase the complication rate of gastrectomy for gastric cancer.

Accurate Risk Stratification of Patients with Node-Positive Gastric Cancer by Lymph Node Ratio.

BACKGROUND: We aimed to clarify the utility of lymph node ratio (LNR) for assessing the prognosis of patients with node-positive gastric cancer after curative gastrectomy. METHODS: We retrospectively analyzed data of 973 patients with node-positive gastric cancer who had undergone curative gastrectomy at nine institutions from 2010 to 2014. Survival analysis was performed by comparing LNR low and high groups according to the optimal cutoff value of LNR, which was determined using receiver operating characteristic curve analysis. RESULTS: LNR high was significantly associated with shorter disease-free survival and was an independent predictor of recurrence in all patients. Moreover, we obtained the similar results from analysis of each N stage. The prevalence of lymph node and peritoneal recurrence appeared to be higher in the LNR high group. Correlation analysis showed that LNR was negatively correlated with the number of retrieved nodes within every N stage; however, disease-free survival did not differ significantly between LNR low and high groups of each N stage with 16-30, 31-40, or >40 retrieved nodes. CONCLUSIONS: LNR is a strong prognostic factor and predictor of recurrence in patients with node-positive gastric cancer who have undergone curative gastrectomy. The combination of LNR and N staging permits more accurate prognostic stratification of patients with gastric cancer and may contribute to developing novel prognostic models.

Survival times are similar among patients with peritoneal, hematogenous, and nodal recurrences after curative resections for gastric cancer.

BACKGROUND: The three dominant recurrence patterns of gastric cancer are peritoneal, hematogenous, and nodal recurrence. Correlation between initial recurrence site and prognosis is poorly understood, particularly after standardization of postoperative S-1 adjuvant chemotherapy. METHODS: We analyzed a multi-institutional database of 3484 patients who underwent gastrectomy for gastric cancer between 2010 and 2014. Patients who experienced recurrences after curative gastrectomy classified into peritoneal, hematogenous, or nodal recurrence groups, according to their initial recurrence sites, and their prognoses were compared. RESULTS: We included 313 patients in the analysis, of whom 190 patients (63%) were treated with postoperative adjuvant chemotherapy. Pathological disease states were stage I: n = 20 (6%), stage II: n = 62 (20%), and stage III: n = 231 (74%). Patients were categorized into groups by peritoneal (n = 127), hematogenous (n = 123), and nodal (n = 63) recurrence. The peritoneal recurrence group tended to have longer recurrence-free survival, but shorter post-recurrence survival, than the other two groups. Median disease-specific survival after curative resection by group were peritoneal: 25.8 months, hematogenous: 29.0 months, and nodal: 27.8 months (peritoneal vs hematogenous, P = .152; hematogenous vs nodal, P = .955; peritoneal vs nodal, P = .213). CONCLUSIONS: Prognoses after curative resection for gastric cancer were similar among patients with peritoneal, hematogenous, or nodal recurrences.

D2 lymph node dissection confers little benefit on the overall survival of older patients with resectable gastric cancer: a propensity score-matching analysis of a multi-institutional dataset.

PURPOSE: Aging societies comprise an increasing number of elderly gastric cancer (GC) patients. We herein attempted to determine whether D2 lymphadenectomy is beneficial for older GC patients. METHODS: We retrospectively analyzed a multi-institutional dataset including 3484 patients who received surgical resection for GC. For the analysis, we selected patients aged ≥ 80 years who were clinically diagnosed with T1N + or T2-4 GC. To balance the essential variables including the type of gastrectomy and the stage of progression, propensity score matching was conducted, and we compared the background clinical factors and postoperative outcomes of the patients allocated to the D2 (n = 87) and non-D2 (n = 87) dissection groups. RESULTS: The D2 group had significantly longer operative times, more blood loss, and more retrieved lymph nodes (median 32 vs 24, P < 0.001) than the non-D2 group. The D2 group had a greater incidence of intra-abdominal abscesses (grade ≥ II in the Clavien-Dindo classification) than the non-D2 group (3.5% vs 0%, P = 0.040). The overall disease-specific and relapse-free survival rates of the D2 group tended to be poorer than those of the non-D2 group (hazard ratios 1.49, 1.70 and 1.14, respectively). CONCLUSIONS: D2 lymphadenectomy for older patients with GC conferred little benefit regarding overall survival despite an occurrence of increased complication rates.

Systemic Inflammation Score as a Predictor of Pneumonia after Radical Resection of Gastric Cancer: Analysis of a Multi-Institutional Dataset.

BACKGROUND: Curative treatment for gastric cancer (GC) comprising gastrectomy with systematic lymph node dissection can result in postoperative complications. Postoperative pneumonia is sometimes fatal, like surgery-related complications such as anastomotic leakage. In this retrospective study, we analyzed a multi-institutional collaborative dataset with the aim of identifying predictors of postgastrectomy pneumonia. METHODS: From a retrospective database of 3,484 patients who had undergone gastrectomy for GC at nine Japanese institutions between 2010 and 2014, 1,415 patients who met all eligibility criteria were identified as eligible for analysis. Predictive values of 31 candidate variables for postoperative pneumonia were assessed. RESULTS: Forty-two patients (3.0%) had grade II or higher postoperative pneumonia. Preoperative systemic inflammation score (SIS) had the greatest area under the curve (0.655) for predicting postoperative pneumonia (optimal cutoff value = 2). The odds ratio (OR) of high SISs associated with postoperative pneumonia was 3.10 (95% confidence interval [CI], 1.54-6.07; p < 0.001). Multivariate binomial logistic analysis identified high SIS as an independent risk factor for postoperative pneumonia (OR, 2.31; 95% CI, 1.19-4.48; p = 0.013). A forest plot revealed that ORs of high SISs were highest in female patients. CONCLUSIONS: Our findings indicate that the preoperative SIS may serve as a simple predictor of postgastrectomy pneumonia, assisting physicians' efforts to take preventive measures against this complication.

Association between Lymphovascular Invasion and Recurrence in Patients with pT1N+ or pT2-3N0 Gastric Cancer: a Multi-institutional Dataset Analysis.

PURPOSE: Patients with pathological stage T1N+ or T2-3N0 gastric cancer may experience disease recurrence following curative gastrectomy. However, the current Japanese Gastric Cancer Treatment Guidelines do not recommend postoperative adjuvant chemotherapy for such patients. This study aimed to identify the prognostic factors for patients with pT1N+ or pT2-3N0 gastric cancer using a multi-institutional dataset. MATERIALS AND METHODS: We retrospectively analyzed the data obtained from 401 patients with pT1N+ or pT2-3N0 gastric cancer who underwent curative gastrectomy at 9 institutions between 2010 and 2014. RESULTS: Of the 401 patients assessed, 24 (6.0%) experienced postoperative disease recurrence. Multivariate analysis revealed that age ≥70 years (hazard ratio [HR], 2.62; 95% confidence interval [CI], 1.09-7.23; P=0.030) and lymphatic and/or venous invasion (lymphovascular invasion (LVI): HR, 7.88; 95% CI, 1.66-140.9; P=0.005) were independent prognostic factors for poor recurrence-free survival. There was no significant association between LVI and the site of initial recurrence. CONCLUSIONS: LVI is an indicator of poor prognosis in patients with pT1N+ or pT2-3N0 gastric cancer.

Propensity-score-matched analysis of a multi-institutional dataset to compare postoperative complications between Billroth I and Roux-en-Y reconstructions after distal gastrectomy.

BACKGROUND: Few well-controlled studies have compared postoperative complications between Billroth I (B-I) and Roux-en-Y (R-Y). The aim of the present study was to compare the incidence of overall and severe postoperative complications by reconstruction method after distal gastrectomy. METHODS: We performed a multi-institutional dataset study of patients who underwent distal gastrectomy with B-I or R-Y reconstruction from 2010 to 2014. Using propensity scores to strictly balance the significant variables, we compared postoperative complications between the techniques. RESULTS: After matching, we enrolled 1014 patients (n = 507 in each group). The incidence of postoperative complications in the R-Y group was significantly higher vs the B-I group (29% vs 17%, P < 0.0001). The incidence of intra-abdominal abscess (4.3% vs 1.8%, P = 0.0177), bowel obstruction (2.6% vs 0.6%, P = 0.0203), and delayed gastric emptying (5.3% vs 1.0%, P < 0.0001) in the R-Y group was significantly higher vs the B-I group, respectively; we saw no significant difference in leakage (3.4% vs 4.1%, P = 0.5084). The incidence of grade ≥ III severe postoperative complications in the R-Y group was significantly higher vs the B-I group (13% vs 7.1%, P = 0.0013). Multivariable analysis showed that R-Y reconstruction was a strong independent risk factor for overall postoperative complications (odds ratio 1.58, P = 0.0044) and grade ≥ III severe postoperative complications (odds ratio 1.75, P = 0.0127). A forest plot revealed that R-Y reconstruction was associated with a greater risk of both overall and grade ≥ III severe postoperative complications in any subgroups. CONCLUSIONS: R-Y reconstruction was associated with increasing overall postoperative complications, as well as severe postoperative complications.

Prognosis After Laparoscopic Gastrectomy in Patients with Pathological Stage II or III Gastric Cancer Who Were Preoperatively Diagnosed with Clinical Stage I: Propensity Score Matching Analysis of a Multicenter Dataset.

BACKGROUND: Laparoscopic gastrectomy (LG) is a standard approach for patients with clinical stage I gastric cancer in East Asia; however, following surgery, these patients may be pathologically diagnosed with stage II or III cancer. The prognosis of patients with gastric cancer migration from clinical stage I to pathological stage II or III after LG has not been completely clarified. METHODS: To compare the prognosis following LG and open gastrectomy (OG) in patients with pathological stage II or III gastric cancer who were preoperatively diagnosed with stage I cancer, we conducted a retrospective analysis using a multicenter dataset comprising details of 3480 patients who underwent gastrectomy between 2010 and 2014 at nine participating institutions. We used propensity score matching to reduce selection bias. RESULTS: After propensity score matching, 146 patients were finally selected. There were no significant differences in the number of dissected lymph nodes. Morbidity rates, length of postoperative hospital stay, and time between surgery and initiation of adjuvant chemotherapy were comparable between the two groups. Moreover, there were no significant differences in the overall, disease-specific, and relapse-free survival rates between the LG and OG groups. The LG group tended to have more patients with hematogenous recurrence, whereas the OG group tended to have more patients with peritoneal recurrence. CONCLUSIONS: Our multicenter dataset analysis indicated that the prognosis of patients with gastric cancer migration from clinical stage I to pathological stage II or III was independent of the surgical approach.

Tumor size ≥50 mm as an Independent Prognostic Factor for Patients with Stage II or III Gastric Cancer After Postoperative S-1 Monotherapy: Analysis of a Multi-institution Dataset.

BACKGROUND: Little is known about the changes in prognostic factors after adjuvant S-1 monotherapy has become widespread as a standard of care for patients with gastric cancer (GC) in East Asia. The present study compared prognostic factors of patients with stage II/III GC treated with or without S-1 adjuvant to formulate appropriate risk stratification strategies. METHODS: We designed a large multicenter dataset and retrospectively analyzed 847 patients with GC stage II or III, who underwent curative gastrectomy between 2010 and 2014. Clinicopathological features and prognostic factors were compared between the two patient groups: surgery-alone (n = 266) and S-1 adjuvant (n = 581). RESULTS: There were no significant differences in pathological tumor depths, nodal status, and disease stages between groups. Recurrence-free survival was significantly longer in the S-1 adjuvant group. For the surgery-alone group, independent prognostic factors were (in order of hazard ratio): (1) invasive growth, (2) high preoperative carcinoembryonic antigen levels, (3) total gastrectomy. For the S-1 adjuvant group, macroscopic tumor size (≥50 mm) was identified as another independent prognostic factor next only to pN2/3. There was overlap between the survival curves of patients with tumor size ≥50 mm in both groups. After receiving adjuvant S-1 monotherapy, ≥50 mm patients had significantly higher prevalence of peritoneal and lymph node metastasis as initial recurrences compared with <50 mm patients. CONCLUSIONS: Adjuvant S-1 monotherapy may alter listing of adverse prognostic factors of stage II and III patients. Macroscopic tumor size ≥50 mm may serve as an important determinant for risk stratification to identify patients who require more intensive treatment.