Multivisceral resection compared to standard gastrectomy for gastric adenocarcinoma: A propensity score-matching analysis.

BACKGROUND: Multivisceral resection (MVR) in locally advanced gastric cancer (GC) is a morbid procedure. However, the precise impact of removing additional organs remains controversial. This study aimed to compare the outcomes of MVR versus standard gastrectomy (SG) in an unbiased cohort. METHODS: Patients who underwent curative-intent surgery for gastric adenocarcinoma were considered. Those submitted to SG were compared to the ones who received MVR using Propensity Score Matching (PSM) analysis. RESULTS: A total of 685 GC patients were included (621 SG and 64 MVR). Groups were distinct concerning the extent of the gastrectomy, tumor size, pTNM, R0, postoperative complications, and 90-day mortality. After PSM, 57 patients were matched in each group. All variables assigned in the score were well matched. Postoperative complication, 90-day mortality, and overall survival (OS) became similar among groups. Age >65 years old and resection of two or more organs, besides the stomach, were factors associated with 90-day mortality. R1 and not received multimodal therapy were independent prognostic factors for worse OS. CONCLUSIONS: After PSM, the difference in morbidity, mortality, and survival of MVR compared to SG was no longer statistically significant, suggesting that MVR is an acceptable therapeutic strategy to patients with advanced GC.

D2 Lymphadenectomy According to the Arterial Variations in Gastric and Hepatic Irrigation.

BACKGROUND: D2 lymphadenectomy for gastric cancer is technically demanding and requires clearance of the lymph node stations along the main arteries that irrigate the stomach and the liver. As gastric and hepatic irrigation have a different pattern from the classic branching of the celiac trunk in approximately 25% of patients, acquaintance with these variations and knowledge on how to adequately perform the lymphadenectomy in different anatomic settings is of utmost importance for surgeons who manage gastric cancer.1 METHODS: This video demonstrates, step-by-step, how to perform D2 lymphadenectomy in accordance with gastric and hepatic irrigation. Illustrations of the arterial variation correlate with the corresponding computed tomography image and operative management of the lymph node stations. DISCUSSION: D2 lymphadenectomy is the standard of care in advanced gastric cancer.2 It implies clearing the lymph node stations along the celiac trunk, left gastric artery, and common and proper hepatic arteries. However, the celiac trunk and hepatic irrigation are highly variable and surgeons must be aware of how to properly and safely address the lymph node stations in all scenarios. Vessel anatomical variations increase the risk of vascular injuries and its complications, such as bleeding, necrosis, liver function impairment, liver necrosis, and conversion to open surgery.3-5 Additionally, the lymphadenectomy cannot be compromised if a variation is found.6 Preoperative knowledge of the gastric blood supply also shortens the surgical duration.7 CONCLUSIONS: The present video demonstrates how to recognize the most common variations found during D2 gastrectomy, and provides strategies to adequately approach them.

Epstein-Barr Virus Positive Gastric Cancer: A Distinct Subtype Candidate for Immunotherapy.

BACKGROUND: Epstein-Barr virus (EBV) positive gastric cancer (GC) has been described as a distinct molecular subtype of the disease, especially associated with gastric carcinoma with lymphoid stroma (GCLS). The possibility that EBV associated GC (EBVaGC) had better prognosis and may be susceptible to immunotherapy has increased the interest in this subtype. However, immune checkpoint and survival of EBVaGC are still controversial, especially with regard to GCLS and conventional gastric adenocarcinoma (CGA). This study aimed to evaluate the clinicopathological characteristics, immunohistochemical profiles and prognosis of EBVaGC according to the histological type GCLS and CGA. METHODS: we retrospectively evaluated a series of EBVaGC who underwent gastrectomy with D2-lymphadenectomy. Biomarkers and tumor-infiltrating cells were evaluated by immunohistochemistry. PD-L1 was evaluated using a combined positive score (CPS). RESULTS: From a total of 30 EBVaGC, 14 (46.7%) were identified as GCLS and 16 (53.3%) as CGA (9 Intestinal, 6 diffuse, 1 undetermined). There were no significant differences in age, sex, and pTNM between GCLS and CGA. CPS-positivity and high-CD8+ was significantly higher in GCLS compared with CGA (P = 0.007 and P = 0.005, respectively). Diffuse EBVaGC had worse survival than intestinal type (P = 0.020). There was no difference in survival between GCLS and intestinal CGA (P = 0.260). In multivariate analysis, CPS and pN status were related with survival in EBVaGC. CONCLUSIONS: CGLS was associated with a predominance of CD8+ cell infiltration and PD-L1 expression. CPS and lymph node metastasis were independent factors associated with prognosis in EBVaGC. These results suggest that specifically EBV-positive GCLS may be prime candidates for PD-1 directed therapy.

Cytotoxic T-lymphocyte-associated protein 4 in gastric cancer: Prognosis and association with PD-L1 expression.

BACKGROUND: Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is one of the most studied immune checkpoint in gastric cancer (GC). However, the prognostic role of CTLA-4 expression in GC is poorly described. This study aimed to evaluate CTLA-4 expression in GC and its impact on survival, including patients treated with standard platinum-based chemotherapy (CMT), and association with PD-L1 expression. METHODS: All GC patients who underwent D2-gastrectomy were investigated retrospectively. Tumor samples were examined for CTLA-4 and PD-L1 by immunohistochemistry. Tumor-infiltrating inflammatory cells, including CD4 + and CD8 + , were also examined. RESULTS: Among the 284 GC patients included, 159 (56%) were CTLA-4 positive and the remaining 125 (44%) were classified as negative. CTLA-4 positive GC was associated with increased inflammatory cell infiltration (p < 0.001), high CD8 + T cells (p = 0.016) and PD-L1 expression (p = 0.026). Considering GC referred for treatment, CTLA-4 negative patients who received CMT had a significant improvement in disease-free survival compared to untreated CLTA-4 negative (p = 0.028). In multivariate analysis, GC positive for both CTLA-4 and PD-L1 had a prognostic impact on survival. CONCLUSION: CTLA-4 positive was associated with PD-L1 expression and a high tumor-infiltrating CD8 + T cells. Accordingly, positivity for both CTLA-4 and PD-L1 was an independent factor associated to better survival in GC patients.

Impact of neoadjuvant chemotherapy on surgical and pathological results of gastric cancer patients: A case-control study.

BACKGROUND AND OBJECTIVE: Neoadjuvant chemotherapy (NACT) followed by radical surgery represents a treatment option for patients with advanced gastric cancer (GC). This case-control study aimed to evaluate the clinicopathological characteristics and surgical outcomes of GC patients who received NACT, and its impact on survival. METHODS: We retrospectively reviewed all patients with GC who underwent gastrectomy. A total of 45 cases with NACT were matched with consecutive 45 patients who underwent upfront gastrectomy for the following characteristics: gender, age, gastrectomy type, lymphadenectomy extent, American Society of Anesthesiologists class, histological type, cT and cN. RESULTS: NACT group had smaller tumors (4.9 vs 6.8 cm P = .006), lower lymphatic invasion rate (40% vs 73.3%, P = .001), lower venous invasion rate (18% vs 46.7%, P = .003) and lower perineural invasion rate (35% vs 77.8%, P < .0001). The ypTNM stage was lower in patients treated with NACT (P < .001). The major postoperative complication (POC) rate was lower in NACT patients (6.7% vs 24.4%, P = .02), as was hospital length of stay (10.8 vs 17 days, P = .005). CONCLUSIONS: NACT allowed nodal and tumor downstaging. In addition, patients who underwent NACT had fewer POC and shorter length of hospital stay.

Lymph node regression after neoadjuvant chemotherapy: A predictor of survival in gastric cancer.

BACKGROUND AND OBJECTIVE: Neoadjuvant chemotherapy (nCMT) has been increasingly used in advanced gastric cancer (GC). However, the prognostic impact of tumor response remains unclear. This study aimed to evaluate if tumor response at the primary site and lymph nodes (LN) correlate with survival in GC patients after nCMT. METHODS: Patients with gastric adenocarcinoma treated with nCMT followed by gastrectomy were evaluated. Residual tumor was graded from 0% to 100%, defining two groups: poor (PR) and major response (MR). LN regression rate (LNRR) was determined based on tumor/fibrosis examination at each LN and a cutoff value established by receiver operating characteristic curve. RESULTS: Among 62 cases, 20 (32.2%) had MR and 42 (67.7%) PR. Smaller size, diffuse histology, lower ypT status and less advanced stage were associated with the MR group. Based on cutoff value of 57, 45.6% and 54.4% patients were classified as low-LNRR and high-LNRR. High-LNRR correlated with absence of venous, lymphatic and perineural invasion, and less advanced stage. Survival was equivalent between MR and PR (P = .956). High-LNRR had better disease-free survival (DFS) than low-LNRR (P < .001). In multivariate analysis, only LNRR associated with DFS. CONCLUSION: High-LNRR associates with DFS in GC treated with nCMT. Response at the primary site does not correlate with survival.

Risk assessment of lymph node metastases in early gastric adenocarcinoma fulfilling expanded endoscopic resection criteria.

BACKGROUND AND AIMS: Early gastric cancer (EGC) is known to present a low rate of lymph node metastases (LNMs). Gastrectomy with D2 lymphadenectomy is usually curative for EGC. Endoscopic submucosal dissection (ESD) is a well-accepted treatment modality for lesions that meet the classic criteria: those mucosal differentiated adenocarcinoma measuring 20 mm or less, without ulceration. Expanded criteria for ESD have been proposed based on a null LNM rate from large gastrectomy series from Japan. Patients with LNM have been reported in Western centers, heightening the need for validation of expanded criteria. Our aim was to assess the risk of LNM in gastrectomy specimens of patients with EGC who met the expanded criteria for ESD. METHODS: We conducted an evaluation of gastrectomy specimens including LNM staging of patients submitted to gastrectomy for EGC in a 39-year retrospective cohort. RESULTS: A total of 389 surgical specimens were included. From them, 135 fulfilled criteria for endoscopic resection. None of the 31 patients with classic criteria had LNM. From the 104 patients with expanded criteria, 3 had LNM (n = 104 [2.9%], 95% confidence interval, .7%-8.6%), all of them with undifferentiated tumors without ulceration, measuring less than 20 mm. CONCLUSIONS: There is a small risk of LNM in EGC when expanded criteria for ESD are met. Refinement of the expanded criteria for the risk of LNM may be desirable in a Brazilian cohort. Meanwhile, the decision to complement the endoscopic treatment with gastrectomy will have to take into consideration the individual risk of perioperative morbidity and mortality.

Immunohistochemical expression of thymidylate synthase and prognosis in gastric cancer patients submitted to fluoropyrimidine-based chemotherapy.

OBJECTIVE: Adjuvant chemotherapy with 5-fluorouracil (5-FU) has been widely used in gastric cancer (GC) patients to prevent relapse after curative resection. 5-FU acts by inhibiting thymidylate synthase (TS), and high levels of TS correlate with resistance to treatment with fluoropyrimidines. The aim of this study was to evaluate the expression of TS in GC patients, and its relation with clinicopathological characteristics and prognosis in adjuvant chemotherapy with 5-FU. METHODS: We retrospectively evaluated 285 patients who underwent D2-gastrectomy with curative intent. TS expression was determined by immunohistochemistry (IHC) in tumor cells by tissue microarray (TMA). TS level was evaluated according to the intensity and percentage of cells marked by a score system. Patients were divided in three groups according to their TS-score: negative, low and high. RESULTS: TS expression was positive in 92.3% of GC. TS-high, TS-low and TS-negative were observed in 46.3%, 46.0% and 7.7% of patients, respectively. High-TS GC were associated with older age (P=0.007), high neutrophil/lymphocyte ratio (P=0.048), well/moderately differentiated histology (P=0.001), intestinal Lauren type (P<0.001) and absence of perineural invasion (P=0.003). Among 285 patients, 133 stage II/III patients (46.7%) received chemotherapy with 5-FU. In survival analysis, TS-high was associated with worse disease-free survival (DFS) in stage III GC patients who received 5-FU-based chemotherapy (P=0.007). Multivariate analysis revealed that total gastrectomy, poorly differentiated tumors and high TS-score were associated with worse DFS in stage III GC patients. CONCLUSIONS: High TS-score in stage III GC was associated with poor DFS in patients treated with fluoropyrimidine-based chemotherapy.

Lymphoepithelioma-like gastric carcinoma: clinicopathological characteristics and infection status.

BACKGROUND: Lymphoepithelioma-like gastric carcinoma (LLGC) is a rare subtype of gastric carcinoma (GC) characterized by prominent lymphocytic infiltration. LLGC may be associated with latent Epstein-Barr virus (EBV) infection or microsatellite instability (MSI). This study aims to assess the clinicopathological characteristics, EBV infection, and MSI status in LLGC. METHODS: A retrospective analysis of GC patients submitted to potentially curative resection between 2009 and 2014 was performed. The LLGC subtype specimens were examined for EBV by in situ hybridization and MSI by immunohistochemical analysis. The LLGC profile was analyzed accordingly to clinicopathological parameters. RESULTS: From 255 patients, seven were identified on the pathological report as LLGC. Six cases were EBV-positive and one had MSI, showing loss of MLH1 and PMS2 expression. LLGC was more frequently seen in men, and the mean age was 69 years. When compared to non-LLGC, LLGC cases were larger (∼5.8 cm) poorly differentiated tumors and had lower incidence of lymph node metastasis (P = 0.045). Mean number of lymph nodes dissected in the LLGC group was 39.5, and only one patient had a single positive lymph node. In addition, two patients presented associated lesions. LLGC was not associated with HER-2, chromogranin and synaptophysin positivity or Helicobacter pylori infection. CONCLUSIONS: Distinct pathological aspects and clinical behavior of LLGC reinforce the need for proper recognition of this histological subtype to choose better therapeutic approaches.

Risk Scoring System to Predict Mortality in Gastric Cancer with Peritoneal Carcinomatosis.

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.

TUMOR MARKERS EXPRESSION LEVELS IN GASTRIC CANCER PATIENT'S PERIPHERAL BLOOD BY RT-PCR ASSESSMENT.

BACKGROUND: Hematological recurrence is the second most frequent cause of failure in the treatment of gastric cancer. The detection of circulating tumor markers in peripheral blood by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) method may be a useful tool to predict recurrence and determine the patient's prognosis. However, no consensus has been reached regarding the association between the tumor markers level in peripheral blood and its impact on patient survival. AIMS: To evaluate the expression of the circulating tumor markers CK20 and MUC1 in peripheral blood samples from patients with gastric cancer by qRT-PCR, and to verify the association of their expression levels with clinicopathological characteristics and survival. METHODS: A total of 31 patients with gastric adenocarcinoma were prospectively included in this study. CK20 and MUC1 expression levels were analyzed from peripheral blood by the qRT-PCR technique. RESULTS: There was no statistically significant (p>0.05) association between CK20 expression levels and clinical, pathological, and surgical features. Higher MUC1 expression levels were associated with female patients (p=0.01). There was a correlation between both gene levels (R=0.81, p<0.001), and CK20 level and tumor size (R=0.39, p=0.034). CONCLUSIONS: CK20 and MUC1 expression levels could be assessed by qRT-PCR from total peripheral blood samples of patients with gastric cancer. CK20 levels were correlated to MUC1 levels as well as to tumor size. There was no difference in disease-free survival and overall survival regarding both genetic markers expression in this series.

PALLIATIVE GASTRECTOMY VERSUS GASTRIC BYPASS FOR SYMPTOMATIC CLINICAL STAGE IV GASTRIC CANCER: A PROPENSITY SCORE MATCHING ANALYSIS.

BACKGROUND: Patients with clinical stage IV gastric cancer may require palliative procedures to manage complications such as obstruction. However, there is no consensus on whether performing palliative gastrectomy compared to gastric bypass brings benefits in terms of survival. AIMS: To compare the overall survival of patients with distal obstructive gastric cancer undergoing palliative surgical treatment, using propensity score matching analysis. METHODS: Patients who underwent palliative bypass surgery (gastrojejunostomy or partitioning) and resection between the years 2009 and 2023 were retrospectively selected. Initial and postoperative clinicopathological variables were collected. RESULTS: 150 patients were initially included. The derived group (n=91) presented more locally invasive disease (p<0.01), greater degree of obstruction (p<0.01), and worse clinical status (p<0.01), while the resected ones (n= 59) presented more distant metastasis (p<0.01). After matching, 35 patients remained in each group. There was no difference in the incidence of postoperative complications, but the derived group had higher 90-day mortality (p<0.01). Overall survival was 16.9 and 4.5 months for the resected and derived groups, respectively (p<0.01). After multivariate analysis, hypoalbuminemia (hazard ratio - HR=2.02, 95% confidence interval - 95%CI 1.17-3.48; p=0.01), absence of adjuvant chemotherapy (HR=5.97; 95%CI 3.03-11.7; p<0.01), and gastric bypass (HR=3,28; 95%CI 1.8-5.95; p<0.01) were associated with worse survival. CONCLUSIONS: Palliative gastrectomy was associated with greater survival and lower postoperative morbidity compared to gastric bypass. This may be due to better local control of the disease, with lower risks of complications and better effectiveness of chemotherapy.

Assessment of programmed death-ligand 1 expression in primary tumors and paired lymph node metastases of gastric adenocarcinoma.

BACKGROUND: Anti-programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) immunotherapy has demonstrated promising results on gastric cancer (GC). However, PD-L1 can express differently between metastatic sites and primary tumors (PT). AIM: To compare PD-L1 status in PT and matched lymph node metastases (LNM) of GC patients and to determine the correlation between the PD-L1 status and clinicopathological characteristics. METHODS: We retrospectively reviewed 284 GC patients who underwent D2-gastrectomy. PD-L1 was evaluated by immunohistochemistry (clone SP142) using the combined positive score. All PD-L1+ PT staged as pN+ were also tested for PD-L1 expression in their LNM. PD-L1(-) GC with pN+ served as the comparison group. RESULTS: Among 284 GC patients included, 45 had PD-L1+ PT and 24 of them had pN+. For comparison, 44 PD-L1(-) cases with pN+ were included (sample loss of 4 cases). Of the PD-L1+ PT, 54.2% (13/24 cases) were also PD-L1+ in the LNM. Regarding PD-L1(-) PT, 9.1% (4/44) had PD-L1+ in the LNM. The agreement between PT and LNM had a kappa value of 0.483. Larger tumor size and moderate/severe peritumoral inflammatory response were associated with PD-L1 positivity in both sites. There was no statistical difference in overall survival for PT and LNM according to the PD-L1 status (P = 0.166 and P = 0.837, respectively). CONCLUSION: Intra-patient heterogeneity in PD-L1 expression was observed between the PT and matched LNM. This disagreement in PD-L1 status may emphasize the importance of considering different tumor sites for analyses to select patients for immunotherapy.

RATIO OF METASTATIC LYMPH NODES VS. RESECTED LYMPH NODES (N-RATIO) HAS PROGNOSTIC IMPLICATIONS IN GASTRIC CANCER.

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.

Prognostic significance of microsatellite instability in patients with resectable gastric cancer.

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.

Peritoneal recurrence in gastric cancer after curative gastrectomy: risk factors and predictive score model.

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.

THE VALUE OF PREOPERATIVE PROGNOSTIC NUTRITIONAL INDEX IN GASTRIC CANCER AFTER CURATIVE RESECTION.

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.

Prognostic implications of tumor-infiltrating lymphocytes within the tumor microenvironment in gastric cancer.

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.

Preoperative albumin-bilirubin score is a prognostic factor for gastric cancer patients after curative gastrectomy.

BACKGROUND: Albumin-bilirubin (ALBI) score is an indicator of liver dysfunction and is useful for predicting prognosis of hepatocellular carcinomas. Currently, this liver function index has been used to predict prognosis in other neoplasms. However, the significance of ALBI score in gastric cancer (GC) after radical resection has not been elucidated. AIM: To evaluate the prognostic value of the preoperative ALBI status in patients with GC who received curative treatment. METHODS: Patients with GC who underwent curative intended gastrectomy were retrospectively evaluated from our prospective database. ALBI score was calculated as follows: (log10 bilirubin × 0.660) + (albumin × -0.085). The receiver operating characteristic curve with area under the curve (AUC) was plotted to evaluate the ability of ALBI score in predicting recurrence or death. The optimal cutoff value was determined by maximizing Youden's index, and patients were divided into low and high-ALBI groups. The Kaplan-Meier curve was used to analyze the survival, and the log-rank test was used for comparison between groups. RESULTS: A total of 361 patients (235 males) were enrolled. The median ALBI value for the entire cohort was -2.89 (IQR -3.13; -2.59). The AUC for ALBI score was 0.617 (95%CI: 0.556-0.673, P < 0.001), and the cutoff value was -2.82. Accordingly, 211 (58.4%) patients were classified as low-ALBI group and 150 (41.6%) as high-ALBI group. Older age (P = 0.005), lower hemoglobin level (P < 0.001), American Society of Anesthesiologists classification III/IV (P = 0.001), and D1 lymphadenectomy P = 0.003) were more frequent in the high-ALBI group. There was no difference between both groups in terms of Lauren histological type, depth of tumor invasion (pT), presence of lymph node metastasis (pN), and pathologic (pTNM) stage. Major postoperative complication, and mortality at 30 and 90 days were higher in the high-ALBI patients. In the survival analysis, the high-ALBI group had worse disease-free survival (DFS) and overall survival (OS) compared to those with low-ALBI (P < 0.001). When stratified by pTNM, the difference between ALBI groups was maintained in stage I/II and stage III CG for DFS (P < 0.001 and P = 0.021, respectively); and for OS (P < 0.001 and P = 0.063, respectively). In multivariate analysis, total gastrectomy, advanced pT stage, presence of lymph node metastasis and high-ALBI were independent factors associated with worse survival. CONCLUSION: The preoperative ALBI score is able to predict the outcomes of patients with GC, where high-ALBI patients have worse prognosis. Also, ALBI score allows risk stratification of patients within the same pTNM stages, and represents an independent risk factor associated with survival.

STAGING LAPAROSCOPY IS STILL A VALUABLE TOOL FOR OPTIMAL GASTRIC CANCER MANAGEMENT.

BACKGROUND: Complete surgical resection is the main determining factor in the survival of advanced gastric cancer patients, but is not indicated in metastatic disease. The peritoneum is a common site of metastasis and preoperative imaging techniques still fail to detect it. AIM: The aim of this study was to evaluate the role of staging laparoscopy in the staging of advanced gastric cancer patients in a Western tertiary cancer center. METHODS: A total of 130 patients with gastric adenocarcinoma who underwent staging laparoscopy from 2009 to 2020 were evaluated from a prospective database. Clinicopathological characteristics were analyzed to identify factors associated with the presence of peritoneal metastasis and were also evaluated the accuracy and strength of agreement between computed tomography and staging laparoscopy in detecting peritoneal metastasis and the change in treatment strategy after the procedure. RESULTS: The peritoneal metastasis was identified in 66 (50.76%) patients. The sensitivity, specificity, and accuracy of computed tomography in detecting peritoneal metastasis were 51.5, 87.5, and 69.2%, respectively. According to the Kappa coefficient, the concordance between staging laparoscopy and computed tomography was 38.8%. In multivariate analysis, ascites (p=0.001) and suspected peritoneal metastasis on computed tomography (p=0.007) were statistically correlated with peritoneal metastasis. In 40 (30.8%) patients, staging and treatment plans changed after staging laparoscopy (32 patients avoided unnecessary laparotomy, and 8 patients, who were previously considered stage IVb by computed tomography, were referred to surgical treatment). CONCLUSION: The staging laparoscopy demonstrated an important role in the diagnosis of peritoneal metastasis, even with current advances in imaging techniques.