ASO Visual Abstract: Persistent Systemic Inflammation Mediates the Impact of Postoperative Complications on Survival after Gastric Cancer Surgery.

Introduction: Coronavirus disease 2019 (COVID-19) was declared to be a global pandemic by the World Health Organization on March 11, 2020. The impact on gastric cancer (GC) surgery is unknown. Various reports have shown data indicating that cancer patients with COVID-19 have high morbidity and mortality rates. The choice of surgical procedures and perioperative management of the patients with malignancy has become even more impor¬tant in the COVID-19 pandemic. In this study, we aimed to evaluate the effects of the COVID-19 pandemic on the preopartive, intraoperative, and postoperative findings of patients operated for gastric cancer in our clinic. Materials and Methods: We defined the ‘COVID-19’ period as occurring between 12-03-2020 and 31-08-2020. All the enrolled patients were divided into two groups, pre-COVID-19 group (Pre-CG; 64 cases) and COVID-19 group (CG; 39 cases). A total of 103 patients with gastric cancer were included in this study. Patient characteristics, preoperative, intraoperative, and postoperative clinicopathological findings were compared between groups. Results: The waiting times before admission increased in CG (Pre-CG [6.73±2.85] vs CG [20.61±5.16] ; p<0.001). After admission, the waiting time before surgery was longer in CG (Pre-CG [5.06±3.06] vs CG [6.89±3.32] ; p=0.006). No significant difference was detected between the groups in terms of operation time, surgical procedure, combine organ resection, intraoperative blood transfusion requirment (p values, respectively; p=0.108; p=0.951; p=0.204; p=0.597). Postoperative complications were oesophagojejunostomy leak (3/1) , atelectasis (2/2), duodenal leak (2/2), ileus (3/0), pleural effusion (2/2), and others (1/1), and there was no statistically significant difference between the two groups (p = 0.333). There was no significant difference between the two groups in terms of hospital stay (p = 0.086) and ICU stay (p = 0.989). Conclusion: In this study, it was seen that the COVID-19 pandemic did not affect morbidity and mortality in gastric cancer surgery, but it prolonged admission waiting and operation waiting times. Since there is very little data in the literature regarding the effect of COVID-19 on gastric cancer surgery, our study will guide future studies on this subject. Keywords: COVID-19, Impact, Gastric Cancer, Pandemics, Surgery

Remnant Gastric Cancer (RGC) describes cancers occurring in the remaining stomach and/or anastomosis in the follow-up after gastric cancer or benign gastric surgery. RGC is diagnosed in esophago-gastroscopy follow-ups of patients who underwent this surgery in the past. Again, the increase in the success of gastric cancer surgery and following medical treatments has increased the incidence of RGC in long-term follow-up after gastric cancer surgery. Laparoscopic surgery has been also reported in few cases. In the present study, the purpose was to present the results of the first five patients that underwent laparoscopic total gastrectomy due to RGC in our clinic. The patients who underwent laparoscopic gastric cancer surgery between November 2014 and December 2018 were evaluated retrospectively. Mean age of the patients was 62.4 years (ranging between 49 and 74 years). Two of these patients had a surgical history due to gastric cancer and 3 due to peptic ulcer. Surgery was completed laparoscopically in all patients. In the early period, one patient had to undergo re-surgery due to stenosis in Jejuno-Jejunostomy, and the patient died. One patient underwent laparotomy due to colonic stenosis in the second month after the surgery. Recurrence was detected on the 140th and 180th days of follow-up in the other two patients. Laparoscopic surgery is a technically applicable method in RGC; however, it is also a risk factor for past surgical postoperative complications. Early recurrence in this group of patients requires a comparison of open and laparoscopic surgery.

4050 Background: We recently showed that cancer cells, with proliferative and tumorigenic potential, can spill into the peritoneal cavity during curative (R0) gastric cancer (GC) surgery, which is associated with peritoneal recurrence (PM). To elucidate the pathophysiology of PM, the relationship between spilled cancer cells and cancer stem cells was evaluated. Furthermore, to identify a therapeutic strategy for PM, the prognostic impact of hyperthermic intraperitoneal chemotherapy (HIPEC) following GC surgery with spillage of cancer cells was evaluated. Methods: Patients with advanced GC (≥pT2 [MP]) who underwent R0 gastrectomy between 2010 and 2015 were enrolled. Ninety-four consecutive patients with negative results in peritoneal cytology and cancer cell culture (CCC [-]) following peritoneal washing (PW) before GC surgery were included. Spilled cancer cells in PW after GC surgery (PW-Post) were examined to identify any CD44-positive cancer stem-like cells associated with cancer metastasis. Based on the PW-Post CCC results, associations between HIPEC and recurrence-free survival (RFS), or overall survival (OS) were evaluated. HIPEC was performed following GC surgery using CDDP, MMC, and 5-FU in 5 L saline maintained at 42˚C for 30 min. Results: Spilled cancer cells included CD44+ cancer stem-like cells. In 48 patients with PW-Post positive CCC (CCC [+]), the number of patients with pStage I, II, and III were 4, 7, and 15, respectively, in those who received HIPEC (n = 26), and 3, 9, and 10, respectively, in those who did not (n = 22). Among patients with CCC (+), the 5-year peritoneal RFS, hepatic RFS, and lymph node RFS rates were 93.3%, 100%, and 68.5%, respectively, in patients who received HIPEC, and 56.7%, 35.6%, and 66.7%, respectively, in those who did not ( P = 0.008, P = 0.008, and P= 0.24, respectively). Among patients with PW-Post CCC (-), none developed recurrence, regardless of whether they received HIPEC (n = 28) or not (n = 18). Conclusions: The results show that PW-Post CCC is a promising predictive biomarker for recurrence after R0 GC surgery. Adjuvant HIPEC performed with R0 GC surgery showed preventive effects on peritoneal and hepatic recurrence and survival benefits for patients with PW-Post CCC (+).

Prevention, diagnosis and treatment of gastric cancer have always been one of the focus of cancer work in China. Currently, the challenges, from the applications of minimally invasive surgical techniques, practices of enhanced reco-very after surgery (ERAS), interdisciplinary and resource integration, and innovation of education and training system of talent development, have being bringing new opportunities to the development of gastric cancer surgery in China. There has been a good working basis for total laparoscopic surgery for gastric cancer and navigation surgery, but surgeons urgently need to conduct further clinical researches, select operative indications and accumulate evidence-based medicine proofs. On the strength of new research methods, ERAS should further select and optimize clinical strategies, and reduce the barriers to entry for application and dissemination. The artificial intelligence and big data technology will meet tremendous opportunities for gastric cancer and interconnection. Talent is the key to breakthrough, nevertheless, further opening research field, using the international advanced training system and training high-quality international talents will always be a cornerstone of the future developments. Gastric cancer surgery in China will make steadily progress toward the precision medicine only if grasping historical opportunities, continuing to promote innovations of technologies and ideas and guaranteeing patients′ benefits would be carried out. Key words: Gastric neoplasms; Surgical therapy; Opportunity; Challenge

Postoperative complications (POCs) are associated with poor long-term outcomes in gastric cancer. However, the underlying biologic mechanisms remain unclear, and systemic inflammation may mediate this association. This study retrospectively analyzed 4177 gastric cancer patients who underwent curative gastrectomy between 2013 and 2018. The neutrophil-to-lymphocyte ratio (NLR) was assessed preoperatively (pre-NLR), on postoperative day 2 (early NLR), and 3 months postoperatively (late NLR). Multivariable Cox and logistic regression models assessed the associations of NLR and POCs with survival and complication risk. For 20.3% of the patients, POCs occurred and were associated with significantly higher NLR at all time points. In the multivariable analysis, early and late NLR independently predicted complication risk. In the Kaplan-Meier survival analysis, POCs were significantly associated with worse overall survival (OS) (hazard ratio [HR], 1.80; p < 0.001) and disease-specific survival (DSS) (HR, 1.80; p < 0.001). However, in multivariate COX regression, POCs were not independently associated with OS or DSS, whereas late NLR remained a significant predictor for both OS (HR, 1.02; p = 0.049) and DSS (HR, 1.03; p = 0.008). When stratified by POC status, high late NLR was significantly associated with worse OS (HR, 2.776; p < 0.001) and DSS (HR, 2.677; p < 0.001) in the POC group. In the no-POC group, high late NLR also was associated with worse OS (HR, 1.587; p < 0.001), but not DSS (HR, 1.274; p = 0.150). Persistent systemic inflammation, reflected by elevated late NLR, is a key mediator of the relationship between POCs and survival. Monitoring persistent inflammation may improve risk stratification and guide management strategies for gastric cancer patients.

Since the first laparoscopic radical surgery for early gastric cancer 30 years ago, there has been a gradual shift from "open" to "minimally invasive" surgery for gastric cancer. This transition is due to advancements in refined anatomy, enlarged field of view, faster recovery, and comparable oncological outcomes. Several high-quality clinical studies have demonstrated the safety and effectiveness of laparoscopy in the treatment of both early and locally advanced gastric cancer. The role of perioperative chemotherapy in managing locally advanced gastric cancer has been widely recognized, and there have been continuous breakthroughs in the exploration of targeted therapy and immunotherapy for perioperative treatment. Additionally, the application of indocyanine green near-infrared imaging technology, 3D laparoscopic technology, and robotic surgery systems has further improved the accuracy and minimally invasive nature of gastric cancer surgeries. Looking ahead, the field of minimally invasive surgery for gastric cancer is expected to become more standardized, resulting in a significant enhancement in the quality of life for gastric cancer patients.

Laparoscopic technology is gradually accepted in gastric cancer surgery, whose efficacy has been demonstrated by some clinical researches. Randomized controlled trials (RCT) are considered as the most important evidence to prove clinical outcomes of laparoscopic surgery for gastric cancer. Korean gastric surgeons have made great contributions to RCT in laparoscopic gastric cancer surgery. KLASS (Korean Laparoscopic Gastrointestinal Surgery Study Group) is one of the most important forerunner and global leader of clinical trials of gastric cancer treatment. KLASS series clinical trials are attracting global attention because of the significant value of surgical treatment for gastric cancer. The RCTs in Korea involve in many aspects of laparoscopic gastrectomy for gastric cancer, including laparoscopy application in early gastric cancer (KLASS-01, KLASS-03 and KLASS-07), advanced gastric cancer (KLASS-02 and KLASS-06), function-preserving gastrectomy (KLASS-04,KLASS-05) and sentinel node navigation surgery (SENORITA trial). In order to share some informations of these RCTs, we review and prospect some important clinical trials of laparoscopic gastric cancer surgery in Korea. With the experience of Korean gastric surgeons, we can make more progress in our own clinical trials of laparoscopic gastric cancer surgery.

Gastric cancer still has a disease-specific 5-yr survival less than 30% and an overall survival of about 15%. The quality of life of patients who undergo gastrectomy is poor owing both to the severity of the disease itself and to the mutilation of the upper gastrointestinal channel after the reconstruction. Therefore, the combination of a jejunal pouch with gastrectomy has been claimed to improve the life quality and nutritional status of these patients. To assess the clinical results after surgery for gastric cancer in two consecutive periods with or without jejunal-pouch reconstruction. 271 consecutive patients referred for surgery for gastric cancer in 1985-1991 (116 patients) and in 1992-1998 (155 patients) in Kanta-Häme central hospital were retrospectively analyzed regarding their disease, mode of surgery, and the immediate and long-term results. In the former observation period gastrectomy was performed with Roux-en-Y esophagojejunostomy without a reservoir, and in the latter period this procedure was combined with a jejunal reservoir. The data were collected from patient journals and from the death certificate obtained from the National Centre of Statistics in Finland. During the study period the incidence of cancer in the cardia increased among the surgical patients from 13.1 to 26.7% (p <0.05). Despite this proximal migration, the cancer-specific 5-yr survival remained practically unchanged during the two study periods, 29.4% and 32.2% (NS). During the period of jejunal-pouch reconstruction there were non-significant increases of the incidences of local recurrence (from 18.9% to 26.5%), of immediate postoperative anastomotic fistulae (from 0.9% to 4.5%) as well as of the immediate mortality (from 2.6% to 3.7%) (NS for each). Despite proximal migration of gastric cancer and the application of a jejunal reservoir, the long-term as well as the immediate results after curative surgery (i.e., D2-gastrectomy) for gastric cancer have remained relatively unchanged. The jejunal-pouch reconstruction with the present technique after gastrectomy can therefore be safely applied.

To analyze the change in postoperative complication rate after gastric cancer surgery registered in the Peking University Cancer Hospital in recent 11 years and the learning curve of complication registration, and to investigate how to improve the complication registration and evaluation in gastric cancer surgery. Patients who underwent open or laparoscopic gastric cancer surgery between April 14, 2005 and February 15, 2016 in our institution were included in the study, and those without essential clinical and administrative data were excluded. Data were biennially collected, and linear regression was performed to investigate the changes of the following parameters, including overall complication rate, severe complication proportion (proportion of complications with Clavien-Dindo score ≥III(a in the total registered complications), re-operation rate and the major complication rate. A total of 5 666 patients were included in the analysis, with 4 111 males (72.56%) and 1 555 females (27.44%). The average age was (58.87±11.50) years and average BMI was(23.15±3.30) kg/m2. There were 305 patients included in the 2005-2006 interval, 810 patients in 2007-2008, 957 patients in 2009-2010, 1 163 patients in 2011-2012, 1 421 patients in 2013-2014, and 1 010 patients in 2015-2016, respectively. The overall re-operation rate was 2.34%(133/5 666), postoperative mortality was 0.41%(23/5 666), registered complication rate was 19.66%(1 114/5 666), severe complication proportion was 32.28%(338/1 047), and the proportion of complication missing the Clavien-Dindo score was 6.01%(67/1 114). The linear regression showed the re-operation rate (r=0.13, P=0.801) and postoperative mortality (r=0.58, P=0.231) remained low (< 4% and < 1% respectively) since 2005, and showed no statistical significance. The registered complication rate showed evident increase from 3.93%(12/305) to 29.13%(414/1 421) between 2005 and 2014 (r=0.92, P=0.010), and slight decrease to 22.77%(230/1 010) in 2015-2016. The severe complication proportion significantly decreased from 6/9 in 2005-2006 to 22.73%(50/220) in 2015-2016 (r=0.90, P=0.014). The proportion of complication missing the Clavien-Dindo score significantly decreased from 25.00%(3/12) in 2005-2006 to 4.35%(10/230) in 2015-2016(r=0.82, P=0.044). The most common complications were infection (9.12%, 517 cases), effusions (6.26%, 355 patients), gastrointestinal motility disorder (4.45%, 252 cases), anastomotic leakage (3.19%, 181 cases) and bleeding (2.31%, 131 cases). The registered rates of these complications all increased since 2005, and the rates of leakage and effusions decreased since 2012 while the others decreased after 2014. According to the data from our institution in the recent 11 years, a learning curve exists in our institution for complication registration in gastric cancer surgery. The administrative data appears to be more reliable than registered complication data in quality and safety evaluation during the learning period. A detailed classification with the Clavien-Dindo score aids to the use of complication data for the quality and safety measurement.

Introduction: Preoperative anaemia is common in gastric cancer patients. Although restrictive blood product transfusion strategies have been introduced, their use in standard practice is not well known. This national register study investigated the perioperative haemoglobin and platelet levels and the use of blood product transfusions in gastric cancer surgery. Methods: In order to improve and unify blood transfusion policies, the Finnish Red Cross Blood Service carried out a project concerning the optimal use of blood products (VOK project). These register data were used to form the patient population containing 70% of blood product transfusions in Finland. Patients undergoing open surgery for gastric cancers were included. Results: A total of 500 patients were included. Perioperative anaemia was observed in 75% of males and 52% of females. Fifty-one percent of patients received blood transfusions, with a median transfusion trigger point of 91 g/L [IQR 84–98 g/L] and a median 3 units transfused [IQR 2–4 units]. Seven percent received platelet transfusion (median trigger 77, IQR 15–146; median 4 units, IQR 2–8), and 6.5% received either fresh frozen plasma or pooled human plasma products. At discharge, the median haemoglobin level was 109 g/L in non-transfused patients and 114 g/L in transfused patients. If restrictive strategies had been applied, only 1.7% (n = 9) had required blood and 0.5% (n = 3) had a platelet transfusion. Conclusion: Anaemia is common among patients undergoing gastric cancer surgery. We encourage clinicians to follow restrictive transfusion policies in gastric cancer patients as Hb levels seem to recover after gastric surgery without blood transfusions.

Objective To analyze the factors influencing the application of enhanced recovery after surgery (ERAS) in gastric cancer with the two classification logistics regression method. Methods A retrospective analysis of the recovery after gastric surgeries was carried out on one hundred and eight patients who suffered from gastric malignant tumor between March 2015 and October 2016, to find out the influencing factors on ERAS for gastric cancer. Results The regression analysis showed that jejunostomy, TNM staging, total gastric or distal gastrectomy, postoperative exhaust time and early postoperative diet were factors influencing the rapid rehabilitation after gastric cancer surgery; the non standardized coefficiency were 5.813, -2.571, -0.944, 1.332, -5.032, the standard errors were 2.439, 1.279, 5.481, 0.575, 1.331, and P values were 0.017, 0.044, 0.049, 0.021, 0.000, respectively. Logistics regression model was established by significance test (χ2=99.96, P<0.01), and the effective rate of the model was 89.8%. Conclusions Whether jejunostomy is performed during the operation, TNM staging of gastric cancer, total gastric or distal gastrectomy, postoperative exhaust time and early diet may be the factors affecting the rapid recovery of gastric cancer after operation, in which intraoperative jejunostomy, early TNM staging, without total gastrectomy, postoperative early stage fast rehabilitation diet, and postoperative exhaust time are the promotion factors. Late TNM stage of gastric cancer and total gastrectomy during operation may delay rapid recovery. Key words: Stomach neoplasms; Enhanced recovery after surgery; Logistic models; Factor analysis, statistical

BackgroundRecent studies have shown that body composition is an important factor affecting surgical outcomes. In this study, we investigate the effect of sarcopenic obesity on surgical site infection (SSI) after gastric cancer surgery.MethodsWe performed a retrospective cohort study of 1,038 patients who underwent gastric cancer surgery between January 2015 and December 2015 at tertiary care hospital in Seoul, Korea. Visceral fat area (VFA) and total abdominal muscle area (TAMA) were assessed at preoperative staging computed tomography scan. Sarcopenic obesity was defined as high VFA/TAMA ratio and receiver operating characteristic (ROC) curves were used to determine the threshold of VFA/TAMA ratio to predict SSI after gastric cancer surgery. Multivariate logistic regression analysis was used to identify independent risk factors for SSI.ResultsOf the 1,038 eligible patients, 58 patients (5.6%) developed SSI. The average value of VFA/TAMA is 2.69 ± 1.43 in non-SSI group and 3.38 ± 1.34 in SSI group (P < 0.001). By using ROC curve, the cut-off value of VFA/TAMA to predict SSI is 3 (AUC 0.653; sensitivity 67%, specificity 61%). Multivariate analysis indicated that smoking (odds ratio (OR), 1.99; 95% confidence interval (CI), 1.1–3.62; P = 0.024), total gastrectomy (OR, 2.45; 95% CI, 1.36–4.42; P = 0.003), stage III, IV cancer (OR, 2.58; 95% CI, 1.44–4.63; P = 0.001) and sarcopenic obesity (OR, 2.85; 95% CI, 1.6–5.06; P < 0.001) were independent risk factors for SSI after gastric cancer surgery. In sarcopenic obesity patients, the incidence rate of Clavien–Dindo score IIIa or higher postoperative complication (7.1% vs. 4%; P = 0.028), mean days of postoperative hospital stay (8.42 ± 7.93 vs. 7.12 ± 3.54; P < 0.001), and the incidence rate of delayed complications requiring re-admission within 30 days (6.1% vs. 2.7%; P = 0.007) were statistically significantly higher than those of the nonsarcopenic obesity patients.ConclusionSarcopenic obesity is an independent risk factor for the development of SSI after gastric cancer surgery. In addition, sarcopenic obesity is associated with high incidence of postoperative complication, prolongation of postoperative hospital stay and an increase of re-admission rate within 30 days.DisclosuresAll authors: No reported disclosures.

4092 Background: Numerous studies suggest positive relationship between hospital volume and cancer treatment outcomes, the surgeon’s experience and specialty training may also be important. This was examined in a high volume hospital in Shanghai among patients who underwent gastric cancer (GC) surgery. Methods: Data on consecutive patients (pts) undergoing R0 or R1 GC resection in Zhongshan hospital between January 2003 and June 2010 were collected and analyzed. Follow-up on pts who were non-Shanghai residents were less complete therefore excluded. Post-operative mortality, pathologic results and survival outcome for pts treated by surgical training, i.e., sub-specialized vs., non-specialized, were obtained. Survival was calculated by the Kaplan-Meier method and Log-rank test was used to determine statistical significance. To determine whether sub-specialty surgical training was an independent factor for overall survival (OS), univariate and multivariate analyses were performed using Cox proportional hazards regression. Results: Total 5,046 pts underwent R0 or R1 GC resection were identified.1594 pts had complete covariate data, survival information and were included in the study. Of them, the sub-specialized group included 217 cases treated by 3 surgeons, while the non-specialized group included 1377 cases treated by 52 surgeons. 5-year cumulative OS was higher in the sub-specialized group (62.9% vs. 54.6%, p=0.032). Multivariate analysis showed that tumor stage(p&lt;0.001), location of tumor (p=0.003), vascular invasion (p&lt;0.001) and surgeon (HR=1.54, p=0.001) were all associated with OS. The incidence of positive margin was higher in non-specialized group (2.0% vs. 2.7%, p&lt;0.001) and the probability of retrieved lymph nodes less than 15 was more in non-specialized group (25.9% vs. 7.3%, p&lt;0.001). Postoperative mortality was also higher in non-specialized group than in specialized group(1.5% vs. 0.9%, p&lt;0.001). Conclusions: In high volume general hospital, sub-specialty training is desirable in gastric cancer surgery, the quality of gastric cancer surgery can be further improved by sub-specialty training leading to better treatment outcome.

Enhanced recovery after surgery (ERAS) versus standard recovery for elective gastric cancer surgery: A meta-analysis of randomized controlled trials

Invasive fungal infection (IFI) related to surgery in elderly patients is often associated with high morbidity and mortality. The aim of the present study was to determine 1,3-β-D-glucan (βDG) levels after gastric cancer surgery in elderly patients and to prospectively evaluate the efficacy of pre-emptive antifungal therapy using βDG as an aid for the early diagnosis of IFI. In all, 81 patients aged ≥70 years who had undergone gastric cancer surgery between 2009 and 2011 were prospectively enrolled in the study. Patients with plasma βDG levels >11 pg/mL (the cut-off value) were randomly assigned to either receive antifungal treatment or not (n=13 in each group). Postoperative outcomes were assessed using various clinical parameters. After gastric cancer surgery, plasma βDG levels were ≥11 pg/mL in 26 of 81 elderly patients (32.1%). Of the βDG-positive patients, significantly more had stages III and IV rather than stages I and II disease (44.1% vs 23.4%, respectively; P=0.049). Fever on postoperative day 8 was significantly reduced in the pre-emptive antifungal-treated group than in the control group (36.8°C vs 37.2°C, respectively; P=0.045). However, there were no significant differences in mortality, morbidity, βDG levels, white blood cell count, and C-reactive protein levels between the two groups. Pre-emptive antifungal treatment based on βDG after gastric surgery in elderly patients may help reduce the incidence of postoperative fever and suppress IFI. However, this needs to be confirmed in a larger prospective randomized, controlled trial.