BACKGROUND:Gastric neuroendocrine tumors (gNETs) are uncommon neoplasms arising from enterochromaffin-like cells, representing a distinct subset of gastric malignancies, with challenging clinical management. AIMS:To analyse the classification, treatment indication, and survival of patients diagnosed with gNETs. METHODS:We retrospectively analyzed patients diagnosed with gNETs between 2009 and 2025 at a high-volume tertiary center in Brazil. Clinical, pathological, and treatment data were reviewed, and tumors were classified according to World Health Organization and clinicopathological criteria into Types I, II, and III. RESULTS:Of the 75 patients included, 53 (70.7%) were classified as Type I, 5 (6.7%) as Type II, and 17 (22.6%) as Type III. Treatment included surgery in 25 patients (33.3%) and endoscopic resection in 50 (66.7%). Type I tumors predominated in females (p<0.001), were frequently multifocal (p<0.001), associated with higher body mass index (p=0.002), and were mainly managed endoscopically (p=0.008). Type II tumors were rare and associated with multiple endocrine neoplasia Type 1, while Type III tumors were predominantly male, larger, high-grade (G3), and frequently metastatic, requiring surgical resection and palliative therapy. Among the 25 surgically treated patients, most were men (52%) and included 12 patients (48.0%) with Type I, 3 (12.0%) with Type II, and 10 (40.0%) with Type III tumors. Survival analysis showed significantly worse outcomes for Type III and G3 tumors. Multivariable analysis identified advanced age (hazards ratio 4.11; 95% confidence interval (95%CI): 1.14-14.80; p=0.030) and tumor, lymph node, metastasis (TNM) stage III/IV (HR 5.42; 95%CI: 1.26-23.26; p=0.023) as independent predictors of poorer survival. CONCLUSIONS:gNETs exhibit heterogeneous clinical behavior, with Type I tumors predominating in the Brazilian population. Tumor type, grade, and TNM stage are critical determinants of prognosis and should guide individualized treatment strategies. CENTRAL MESSAGE:The stomach is the most frequent site of gastrointestinal neuroendocrine neoplasms (NENs), with an annual incidence of approximately 0.4 per 1,00,000 individuals. According to the most recent World Health Organization Classification of Tumors of the Digestive System, NENs are divided into three major categories: gastric neuroendocrine tumors, which are the most common, well-differentiated, and have any grade; neuroendocrine carcinomas, which are poorly differentiated and high-grade; and mixed neuroendocrine-non-neuroendocrine neoplasms, which are aggressive and harbor multiple molecular alterations. These neoplasms originate from enterochromaffin-like cells of the gastric mucosa. PERSPECTIVES:Gastric neuroendocrine tumors (gNETs) are uncommon and heterogeneous, and require individualized management. In this largest Brazilian cohort, Type I gNET predominated, showing indolent behavior and favorable outcomes with endoscopic treatment. Type II tumors were rare and invariably linked to multiple endocrine neoplasia type 1, while Type III tumors presented aggressive features, advanced stage, and poor survival. Prognosis was strongly determined by tumor, lymph node, metastasis stage, highlighting the importance of accurate staging and histopathological evaluation.

BackgroundRobot-assisted gastrectomy (RG) has been shown to be safe and feasible in the treatment of gastric cancer (GC). However, it is unclear whether RG is equivalent to laparoscopic gastrectomy (LG), especially in the Western world. Our objective was to compare the outcomes of RG and LG in GC patients.MethodsWe reviewed all gastric adenocarcinoma patients who underwent curative gastrectomy by minimally invasive approach in our institution from 2009 to 2022. Propensity score matching (PSM) analysis was conducted to reduce selection bias. DaVinci Si platform was used for RG.ResultsA total of 156 patients were eligible for inclusion (48 RG and 108 LG). Total gastrectomy was performed in 21.3% and 25% of cases in LG and RG, respectively. The frequency of stage pTNM II/III was 48.1%, and 54.2% in the LG and RG groups (p = 0.488). After PSM, 48 patients were matched in each group. LG and RG had a similar number of dissected lymph nodes (p = 0.759), operative time (p = 0.421), and hospital stay (p = 0.353). Blood loss was lower in the RG group (p = 0.042). The major postoperative complications rate was 16.7% for LG and 6.2% for RG (p = 0.109). The 30-day mortality rate was 2.1% and 0% for LG and RG, respectively (p = 1.0). There was no significant difference between the LG and RG groups for disease-free survival (79.6% vs. 61.2%, respectively; p = 0.155) and overall survival (75.9% vs. 65.7%, respectively; p = 0.422).ConclusionRG had similar surgical and long-term outcomes compared to LG, with less blood loss observed in RG.

BACKGROUND:Gastric outlet obstruction due to unresectable tumours is usually managed with a gastrojejunostomy. Unfortunately, the unsatisfactory outcomes of this procedure have led to the search for alternatives, including gastric partitioning. METHODS:Monocentric, randomized, parallel, open-label trial that included patients with obstructive, unresectable distal gastric tumours. The objective was to compare gastric partitioning to gastrojejunostomy, considering the gastric outlet obstruction scoring system scale as the main outcome. Randomization was performed using computer-generated software available online and after the application of the informed consent term, the allocation group was revealed to the surgeon before the surgical procedure. RESULTS:Over 7 years, 90 patients were initially randomized. After applying the inclusion and exclusion criteria, 25 patients were included in the gastrojejunostomy group and 27 in the partitioning group. Both groups were similar regarding initial clinical characteristics including sex, age, weight, clinical performance, and the acceptance of oral diet. Surgery duration, length of hospital stay, postoperative complications, and 30- and 90-day mortality rates were similar between groups. Acceptance of normal diet was more frequently reached by patients in the partitioning group (96% versus 72%; P = 0.022). During outpatient follow-up, maintenance of oral intake and weight was similar between groups. Patients in the partitioning group received more frequent red blood cell transfusions (81% versus 52%; P = 0.024). There was no difference regarding the administration of palliative chemotherapy lines and survival. In the multivariable analysis, the inability to eat a full diet (P = 0.035) and the absence of palliative chemotherapy after the procedure (P = 0.001) were associated with worse survival. CONCLUSIONS:Gastric partitioning provided a better return of the ability to accept food orally. There was no difference regarding postoperative complications and long-term survival. TRIAL REGISTRATION:NCT02065803, clinicaltrials.gov.

Background Tumor-infiltrating lymphocytes (TILs) play a regulatory role in the tumor-associated immune response and are important in the prognosis and treatment response of several cancers. However, because of its heterogeneity, the prognostic value of TILs in gastric cancer (GC) is still controversial. Thus, this study aimed to investigate the association between the density of TILs and patients' outcomes in GC. Methods Patients with gastric adenocarcinoma who underwent curative intent gastrectomy were retrospectively investigated. The groups for analysis were determined on the basis of TIL intensity and percentage of CD3+ T-cell infiltration by immunohistochemical. Furthermore, Epstein-Barr virus (EBV), microsatellite instability (MSI), T-cell ratio of CD4 to CD8, and programmed death protein ligand 1 (PD-L1) status were evaluated. Results A total of 345 patients were enrolled: 124 patients with GCs (35.9%) were classified as the low-CD3+ TIL group, and 221 patients with GCs (64.1%) were classified as the high-CD3+ TIL group. Poorly differentiated histology (P = .014), EBV-positive status (P < .001), PD-L1-positive status (P = .001), and CD4 < CD8 (P < .001) were associated with high-CD3+ GC. There was no difference regarding MSI status, the degree of tumor invasion (pT), the presence of lymph node metastasis, and pTNM stage between low- and high-CD3+ groups. In survival analysis, the high-CD3+ group had better disease-free survival and overall survival rates than had the low-CD3+ group (P = .055 and P = .041, respectively). In the multivariate analysis, total gastrectomy, lymph node metastasis, advanced pT stage, and low CD3+ levels were independent factors related to worse survival. Conclusion High CD3+ TILs levels were significantly associated with improved survival and could serve as prognostic biomarkers in GC. In addition, CD3+ T-cell infiltration was related to both EBV-positive and PD-L1-positive GC and may assist in the investigation of targets in immunotherapy.

Background Microsatellite instability (MSI) gastric cancer (GC) generally has a better prognosis than microsatellite-stable (MSS) GC and has been associated with nonsurvival benefit with the addition of chemotherapy (CMT) compared with surgery alone. However, patients with MSI have distinct clinicopathological characteristics. This study aimed to compare the survival outcomes between patients with MSI GC and those with MSS GC. In addition, this study analyzed the survival outcomes of patients with MSI GC who received CMT. Methods This study reviewed all patients with GC who underwent curative gastrectomy. Patients were divided into MSI group and the MSS group. Propensity score matching (PSM) was used to match clinicopathological factors. Results Among the 378 patients enrolled, 78 (20.6%) had MSI. Older age (P < .001), subtotal gastrectomy (P = .008), pN0 (P = .020), and earlier pTNM stage (P = .012) were associated with MSI GC. Survival analysis showed better disease-free survival (DFS) and overall survival (OS) of patients in the MSI group (P = .012 and P = .019, respectively). After PSM, 78 patients were matched to each group. All variables assigned to the scores were well matched, and both groups became equivalent. After the matching, the differences in DFS and OS according to MSI/MSS status were estimated to be larger than before (DFS: 63.3% vs 41.4%; P = .002; OS: 65.8% vs 42.5%; P = .002). Regarding patients referred for CMT, there was no difference in DFS and OS between patients with MSI GC who underwent CMT and those who underwent surgery alone (P = .255 and P = .178, respectively). Conclusion Even after controlling for clinicopathological characteristics, MSI was identified as a prognostic factor for patient survival. MSI GC showed no significant survival benefit with the addition of CMT.

Background: Multimodal therapy (MMT), comprising surgery alongside perioperative chemotherapy (PCMT) or adjuvant chemotherapy (ACMT), has demonstrated improve in survival compared with surgery alone for advanced gastric cancer (GC). However, the moment of administering chemotherapy for GC is still a matter of debate. This study aimed to compare PCMT and ACMT in patients with locally advanced GC. Method: We included all gastric adenocarcinoma treated with chemotherapy and curative-intent resection. Using propensity score matching (PSM), patients who received PCMT were matched with patients undergoing ACMT for 10 pretreatment variables. Results: Among the 552 patients with indication for MMT, 377 (68.3%) received combining chemotherapy (CMT): 116 (30.8%) PCMT and 261 (69.2%) ACMT. After PSM, 109 patients were matched in each group. All variables assigned in the score were well matched and both groups became equivalent. Patients receiving PCMT had less angiolymphatic and perineural invasion, less advanced pT, pN and pTNM stage than ACMT group (p < 0.001 for all). There was no difference in the postoperative complication rate between both groups (p = 0.551). After the matching, disease-free survival (DFS) and overall survival (OS) became similar between PCMT and ACMT groups (DFS: 51.4% vs. 46.9%, p = 0.882, respectively; OS: 54.3% vs. 48.7%, p = 0.638, respectively). Conclusion: After controlling for pretreatments characteristics, there was no significant difference in survival between GC patients who underwent perioperative and adjuvant CMT. PCMT did not result in an increase in survival, but it provides a decrease in the stage of the disease, with no difference in surgical outcomes.

Background Peritoneal recurrence (PR) remains the most common pattern of relapse in gastric cancer (GC), even after curative resection. Given its dismal prognosis, the identification of risk factors for PR is essential for developing new treatment modalities and selecting a more appropriate subgroup of patients. This study aimed to evaluate the risk factors and survival outcomes of patients with GC who had PR and to develop a risk score to predict PR. Methods All patients with GC who underwent curative gastrectomy were included. For analysis, patients were divided into no recurrence (NR), recurrence in other sites (ROS), and PR. Risk factors for PR were analyzed to build a risk score. Results Among 622 patients with GC, 460 (74.0%) had NR, 98 (15.7%) had ROS, and 64 (10.3%) had PR. Female patients, linitis on computed tomography, depth of tumor invasion, and diffuse/mixed type were associated with PR. Patients with PR had worse overall survival than those with ROS (22.0 vs 29.8 months, respectively; P = .008). The median survival estimates after recurrence were 5.0 months in the PR group and 9.9 months in the ROS group (P < .001). The scoring system developed with 8 variables had an accuracy of 81% in predicting PR. Accordingly, 385 patients (61.9%) were classified as low risk, and 237 patients (38.1%) were classified as high risk. Among the 64 patients with PR, 53 (82.8%) were correctly classified as high risk (P < .001). Conclusion Patients with PR had distinct clinicopathologic characteristics and extremely restricted survival compared with patients with recurrence in other sites. The risk-scoring model was able to identify patients at higher risk of PR.

Background: Some studies have shown that gastrectomy performed by experienced surgeons in high-volume specialized hospitals with the possibility of complete treatment has better results. This study aimed to compare the results of patients who underwent surgery at a reference center with non-specialized centers. Methods: Patients with gastric adenocarcinoma stage as pTNM II and III who underwent curative gastrectomy and were referred for adjuvant chemotherapy between 2009 and 2018 were included. Patients were divided into two groups: patients operated on in a reference center with complete oncological treatment (Reference Group); and those operated on in an external Hospital and referred for adjuvant treatment at the reference center (External Group). Results: A total of 643 patients were evaluated, 307 in the external group and 336 in the reference group. Patients in the external group were younger (58.9 vs. 62.6 years; p < 0.001) and with fewer comorbidities according to the Charlson-Deyo index (p < 0.001). The pathological result showed more dissected lymph nodes (41.4 vs. 23.5; p < 0.001) and a higher R0 resection rate (98.5% vs. 95.1%; p = 0.013) in the reference group. Patients of the external group underwent more adjuvant radiotherapy (49.5% vs. 33.9%; p < 0.001) with no difference concerning adjuvant chemotherapy (p = 0.066). Peritoneal recurrence was more common in the external group (63.2% vs 38.7%, p < 0.001). The disease-free survival rate was higher in the reference group (p < 0.001) as well as overall survival (p = 0.01). Conclusion: Patients who received full oncological treatment at a reference center had better survival outcomes compared to those operated in external services.

BACKGROUND: Lymph node status is vital for gastric cancer (GC) prognosis, but the conventional pN stage may be limited by variations in lymphadenectomy and stage migration. The N-Ratio, which assesses the ratio of metastatic to resected lymph nodes, emerges as a promising prognostic tool. AIMS: To assess N-Ratios prognostic value in GC, particularly in patients with <25 resected lymph nodes. METHODS: Patients who underwent gastrectomy with curative intent for GC were retrospectively evaluated. The N-Ratio categories were determined using the ROC curve method, and the area under the curve (AUC) was used as a measure of performance in predicting recurrence/death. RESULTS: A total of 561 GC patients were included in the study, 57% had pN+ status, and 17.5% had <25 resected lymph nodes. N-Ratio, with a mean of 0.12, predicted survival with 74% accuracy (AUC=0.74; 95%CI 0.70-0.78, p<0.001). N-Ratio categories included: N-Ratio 0 (43%); N-Ratio 1 (12.3%); N-Ratio 2 (31.6%); and N-Ratio 3 (13.2%). Disease-free survival (DFS) varied among all N-Ratio groups, with N-Ratio 3 showing worse survival than pN3 cases (DFS=21.8 vs. 11 months, p=0.022, p<0.05). In cases with <25 resected lymph nodes, DFS was not significantly worse in N-Ratio 0 (68.8 vs. 81.9%, p=0.061, p>0.05) and N-Ratio 1 (66.2 vs. 50%, p=0.504, p>0.05) groups. The DFS of N-Ratio-0 cases with <25 lymph nodes was similar to N-Ratio 1 cases. CONCLUSIONS: N-Ratio influenced survival in GC patients, especially in advanced lymph node disease (N-Ratio 3). Considering that N-Ratio does not impact pN0 cases, individualized prognosis assessment is essential for patients with <25 resected lymph nodes.

Gastric cancer (GC) with peritoneal carcinomatosis (PC) has a particularly unfavorable prognosis. This limited survival raises doubts about which factors confer an extremely worse outcome and which patients could benefit from more aggressive treatments, in an attempt to improve survival and better control the disease. This study aimed to evaluate the survival outcomes of patients with PC due to GC and develop a prognostic score to predict 6-month mortality. We performed an analysis of clinical stage IV GC with PC. Scores were assigned to risk factors and calculated for each patient from nine variables. Among 326 IVB GC, 211 (64.7%) had PC and were included. After calculating the score, 136 (64.5%) GCs were classified as a low-risk group and 75 (35.5%) as a high-risk group. Median OS was 7.9 and 1.9 months for low- and high-risk patients (p < 0.001). In the high-risk group, 77.3% of the patients died in <6 mo (p < 0.001). Palliative surgery and chemotherapy were associated with better survival, and the prognostic groups maintained statistical significance even when the same type of treatment was performed. In conclusion, the scoring system developed with variables related to patient performance status and clinical data was able to distinguish GC with PC with a high risk of 6-month mortality. Accordingly, verifying and validating our findings in a large cohort of patients is necessary to confirm and guarantee the external validation of the results.

ABSTRACT BACKGROUND: Predicting short- and long-term outcomes of oncological therapies is crucial for developing effective treatment strategies. Malnutrition and the host immune status significantly affect outcomes in major surgeries. AIMS: To assess the value of preoperative prognostic nutritional index (PNI) in predicting outcomes in gastric cancer patients. METHODS: A retrospective cohort analysis was conducted on patients undergoing curative-intent surgery for gastric adenocarcinoma between 2009 and 2020. PNI was calculated as follows: PNI=(10 x albumin [g/dL])+(0.005 x lymphocytes [nº/mm3]). The optimal cutoff value was determined by the receiver operating characteristic curve (PNI cutoff=52), and patients were grouped into low and high PNI. RESULTS: Of the 529 patients included, 315 (59.5%) were classified as a low-PNI group (PNI<52) and 214 (40.5%) as a high-PNI group (PNI≥52). Older age (p=0.050), male sex (p=0.003), American Society of Anesthesiologists score (ASA) III/IV (p=0.001), lower hemoglobin level (p<0.001), lower body mass index (p=0.001), higher neutrophil-lymphocyte ratio (p<0.001), D1 lymphadenectomy, advanced pT stage, pN+ and more advanced pTNM stage were related to low-PNI patient. Furthermore, 30-day (1.4 vs. 4.8%; p=0.036) and 90-day (3.3 vs. 10.5%; p=0.002) mortality rates were higher in low-PNI compared to high-PNI group. Disease-free and overall survival were worse in low-PNI patients compared to high-PNI (p<0.001 for both). ASA III/IV score, low-PNI, pT3/T4, and pN+ were independent risk factors for worse survival. CONCLUSIONS: Preoperative PNI can predict short- and long-term outcomes of patients with gastric cancer after curative gastrectomy. Low PNI is an independent factor related to worse disease-free and overall survival.

ABSTRACT BACKGROUND: The COVID-19 pandemic has overloaded healthcare systems worldwide. Other diseases, such as neoplasms, including gastric cancer, remained prevalent and had their treatment compromised. AIMS: The aim of this study was to evaluate the impact of the COVID-19 pandemic on the treatment of gastric cancer and adherence to the recommended preoperative COVID-19 screening protocol. METHODS: A retrospective study evaluated patients diagnosed with gastric adenocarcinoma who underwent surgical treatment between 2015 and 2023. RESULTS: A total of 769 patients with gastric cancer were evaluated and organized into two groups: (i) pre-COVID group and (ii) COVID group. The pre-COVID group consisted of 527 patients operated on between 2015 and 2019, and the COVID group consisted of 242 patients from 2020 to 2023. The average number of surgical procedures per year in the pre-COVID group was 105 and 81 in the COVID group. There was a statistically significant difference between ASA classification (p=0.002) and clinical staging (p=0.015), which were worse in the COVID group. We observed an increase in diagnostic surgeries (p=0.026), with an increase in the minimally invasive route (p<0.001). In patients undergoing curative surgery, there was a greater indication for postoperative ICU (p=0.022) and neoadjuvant chemotherapy (p<0.001). There was no difference in 30- and 90-day mortality. CONCLUSIONS: The surgical and oncological outcomes for patients operated on during the pandemic remained uncompromised, even though many presented with more advanced initial stages and poorer clinical performance. High adherence to protocols and a low rate of complications related to coronavirus indicate that surgeries were performed safely during this period.

This review evaluated the risks and survival benefits of pancreatoduodenectomy associated with venous resection compared with palliative surgery. A systematic review with meta-analysis was performed. Higher overall survival was observed in the pancreatic resection group (HR = 4.000; 95% CI 2.800 to 5.200). However, the palliative group had fewer complications (RD = -0.170; 95% CI -0.260 to -0.070). There was no significant difference in the mortality rates (RD = 0.000; 95% CI -0.030 to 0.030). In centres with experience in pancreatic surgery, resection may be considered for locally advanced cancer and major venous invasion. Pancreaticoduodenectomy with vascular resection may improve survival for periampullary tumours compared with palliation therapy. However, pancreaticoduodenectomy with major venous resection has potentially higher morbidity than palliation therapy. Key Words: Pancreatoduodenectomy, Pancreatic neoplasms, Vascular surgical procedures.