Complement is increased in treatment resistant rectal cancer and modulates radioresistance.

Resistance to neoadjuvant chemoradiation therapy (neo-CRT) is a significant clinical problem in the treatment of locally advanced rectal cancer. Identification of novel therapeutic targets and biomarkers predicting therapeutic response is required to improve patient outcomes. Increasing evidence supports a role for the complement system in resistance to anti-cancer therapy. In this study, increased expression of complement effectors C3 and C5 and increased production of anaphylatoxins, C3a and C5a, was observed in radioresistant rectal cancer cells. Modulation of the central complement effector, C3, was demonstrated to functionally alter the radioresponse, with C3 overexpression significantly enhancing radioresistance, whilst C3 inhibition significantly increased sensitivity to a clinically-relevant dose of radiation. Inhibition of C3 was demonstrated to increase DNA damage and alter cell cycle distribution, mediating a shift towards a radiosensitive cell cycle phenotype suggesting a role for C3 in reprogramming of the tumoural radioresponse. Expression of the complement effectors C3 and C5 was significantly increased in human rectal tumour tissue, as was expression of CFB, a component of the alternative pathway of activation. Elevated levels of C3a and C5b-9 in pre-treatment sera from rectal cancer patients was associated with subsequent poor responses to neo-CRT and poorer survival. Together these data demonstrate a role for complement in the radioresistance of rectal cancer and identify key complement components as potential biomarkers predicting response to neo-CRT and outcome in rectal cancer.

Optimal Treatment Strategies for cT2 Staged Adenocarcinoma of the Esophagus and the Gastroesophageal Junction: A Multinational, High-volume Center Retrospective Cohort Analysis.

OBJECTIVE: A multi-national high-volume center study was undertaken to evaluate outcomes after primary surgery (PS) or neoadjuvant treatment followed by surgery (NAT/S) in cT2 staged adenocarcinomas of the esophagus (EAC) and gastroesophageal junction (GEJ). BACKGROUND: Optimal treatment approach with either NAT/S or PS for clinically staged cT2cNany or cT2N0 EAC and GEJ remains unknown due to the lack of randomized controlled trials. METHODS: Retrospective analysis of prospectively maintained databases from ten centers was performed. Between 01/2012-08/2023 645 patients who fulfilled inclusion criteria of GEJ Siewert type I, II or EAC with cT2 status at diagnosis underwent PS or NAT/S with curative intent. Primary endpoint was overall survival (OS). RESULTS: In the cT2cNany cohort 192 patients (29.8%) underwent PS and 453 (70.2%) underwent NAT/S. In all cT2cN0 patients (n=333), NAT/s remained the more frequent treatment (56.2%). Patients undergoing PS were in both cT2 cohorts older (P<0.001) and had a higher ASA classification (P<0.05). R0 resection showed no differences between NAT/S and PS in both cT2 cohorts (P>0.4).Median OS was 51.0 months in the PS group (95% CI 31.6-70.4) versus 114.0 months (95% CI 53.9-174.1) in the NAT/S group (P=0.003) of cT2cNany patients. For cT2cN0 patients NAT/S was associated with longer OS (P=0.002) and disease-free survival (DFS) (P=0.001). After propensity score matching of cT2N0 patients, survival benefit for NAT/S remained (P=0.004). Histopathology showed that 38.1% of cT2cNany and 34.2% of cT2cN0 patients were understaged. CONCLUSIONS: Due to unreliable identification of cT2N0 disease, all patients should be offered a multimodal therapeutic approach.

Prophylactic negative pressure wound therapy (NPWT) in laparotomy wounds (PROPEL-2): protocol for a randomized clinical trial.

BACKGROUND: A proportion of patients undergoing midline laparotomy will develop surgical site infections after surgery. These complications place considerable financial burden on healthcare economies and have negative implications for patient health and quality of life. The prophylactic application of negative pressure wound therapy devices has been mooted as a pragmatic strategy to reduce surgical site infections. Nevertheless, further availability of multicentre randomized clinical trial data evaluating the prophylactic use of negative pressure wound therapy following midline laparotomy is warranted to definitely provide consensus in relation to these closure methods, while also deciphering potential differences among subgroups. The aim of this study is to determine whether prophylactic negative pressure wound therapy reduces postoperative wound complications in patients undergoing midline laparotomy. METHODS: PROPEL-2 is a multicentre prospective randomized clinical trial designed to compare standard surgical dressings (control arm) with negative pressure wound therapy dressings (Prevena™ and PICO™ being the most commonly utilized). Patient recruitment will include adult patients aged 18 years or over, who are indicated to undergo emergency or elective laparotomy. To achieve 90% power at the 5% significance level, 1006 patients will be required in each arm, which when allowing for losses to follow-up, 10% will be added to each arm, leaving the total projected sample size to be 2013 patients, who will be recruited across a 36-month enrolment period. CONCLUSION: The PROPEL-2 trial will be the largest independent multicentre randomized clinical trial designed to assess the role of prophylactic negative pressure wound therapy in patients indicated to undergo midline laparotomy. The comparison of standard treatment to two commercially available negative pressure wound therapy devices will help provide consensus on the routine management of laparotomy wounds. Enrolment to PROPEL-2 began in June 2023. Registration number: NCT05977816 (http://www.clinicaltrials.gov).

Evaluating the impact of enhanced recovery after surgery protocols following emergency laparotomy - A systematic review and meta-analysis of randomised clinical trials.

INTRODUCTION: Enhanced recovery after surgery (ERAS) protocols are an evidence-based, multidisciplinary, and systematic approach to peri-operative care, which attempt to reduce the anticipated physiological strain on patients after major surgery. This meta-analysis of randomised clinical trials (RCTs) evaluated the impact of ERAS following emergency laparotomy versus standard care. METHODS: A systematic review was performed as per PRISMA guidelines. Meta-analysis was performed using RevMan v5.4. RESULTS: Six RCTs involving 509 patients were included. Patients randomised to ERAS had reduced post-operative nausea and vomiting (PONV) (odds ratio (OR): 0.32, 95 â€‹% confidence interval (CI): 0.20-0.51), time to ambulation (mean difference (MD): 1.67, 95 â€‹% CI: -2.56 to -0.78) and bowel opening (MD: -1.26, 95 â€‹% CI: -2.03 to -0.49), length of stay (LOS) (MD: -2.92 95 â€‹% CI: -3.73 - - 2.10), pulmonary complications (OR: 0.43, 95 â€‹% CI: 0.24-0.75), surgical site (OR: 0.33 95 â€‹% CI: 0.2-0.50) and urinary tract infections (OR: 0.48 95 â€‹% CI: 0.19-1.16). CONCLUSION: ERAS successfully reduced patient recovery, LOS, and complications. ERAS protocols should be deployed, where feasible, for emergency laparotomy.

Evidence for the Positive Impact of Centralization in Esophageal Cancer Surgery.

OBJECTIVE: In this study we analyzed the impact of centralization on key metrics, outcomes and patterns of care at the Irish National Center. SUMMARY BACKGROUND DATA: Overall survival rates in esophageal cancer in the West have doubled in the last 25 years. An international trend towards centralization may be relevant, however this model remains controversial with Ireland, centralizing esophageal cancer surgery in 2011. STUDY DESIGN: All patients (n=1245) with adenocarcinoma of the esophagus or junction treated with curative intent involving surgery, including endoscopic surgery, were included (n= 461 from 2000-2011, and 784 from 2012-2022). All data entry was prospectively recorded. Overall survival was measured (i) for the entire cohort; (ii) patients with locally advanced disease (cT2-3N0-3); and (iii) patients undergoing neoadjuvant therapy. All complications were recorded as per Esophageal Complication Consensus Group (ECCG) definitions, and the Clavien Dindo (CD) severity classification. STATISTICAL ANALYSIS: Data were analyzed using GraphPad Prism (v.6.0) for Windows and SPSS (v.23.0) software (SPSS,Chicago,IL) RStudio (Rversion4.2.2). Survival times were calculated using log-rank test and a Cox-regression analysis, and Kaplan-Meier curves generated. RESULTS: Endotherapy for cT1a/IMC adenocarcinoma increased from 40 (9% total) to 245 (31% total) procedures between the pre-centralization (pre-C) and post-centralization (post-C) periods. A significantly (P<0.001) higher proportion of patients with cT2-3N0-3 disease in the post-C period underwent neoadjuvant therapy (66% vs 53%). Operative mortality was lower (P=0.02) post-C, at 2% vs 4.5%, and>IIIa CD major complications decreased from 33% to 25% (P<0.01). Recurrence rates were lower post-C (38% vs 53%, P<0.01). Median overall survival was 73.83 versus 47.23 months in the 2012-22 and 2000-11 cohorts respectively (P<0.001). For those who received neoadjuvant therapy, the median survival was 28.5 months pre-C and 42.5 months post-C (P<0.001). CONCLUSION: These data highlight improvements in both operative outcomes and survival from the time of centralization, and a major expansion of endoscopic surgery. Although not providing proof, the study suggests a positive impact of formal centralization with governance on key quality metrics, and an evolution in patterns of care.

Management of early oesophageal cancer: An overview.

The incidence of esophageal cancer, namely the adenocarcinoma subtype, continues to increase exponentially on an annual basis. The indolent nature of the disease renders a significant proportion inoperable at first presentation, however, with the increased utilisation of endoscopy, many early lesions are now being identified which are suitable for endotherapeutic approaches. This article details the options available for dealing with early esophageal cancer by endoscopic mean obviating the need for surgery thereby avoiding the potential morbidity and mortality of such intervention.

Analysing the Combined Effects of Radiotherapy and Chemokine Receptor 5 Antagonism: Complementary Approaches to Promote T Cell Function and Migration in Oesophageal Adenocarcinoma.

The presence of an immunosuppressive tumour microenvironment in oesophageal adenocarcinoma (OAC) is a major contributor to poor responses. Novel treatment strategies are required to supplement current regimens and improve patient survival. This study examined the immunomodulatory effects that radiation therapy and chemokine receptor antagonism impose on T cell phenotypes in OAC with a primary goal of identifying potential therapeutic targets to combine with radiation to improve anti-tumour responses. Compared with healthy controls, anti-tumour T cell function was impaired in OAC patients, demonstrated by lower IFN-γ production by CD4+ T helper cells and lower CD8+ T cell cytotoxic potential. Such diminished T cell effector functions were enhanced following treatment with clinically relevant doses of irradiation. Interestingly, CCR5+ T cells were significantly more abundant in OAC patient blood compared with healthy controls, and CCR5 surface expression by T cells was further enhanced by clinically relevant doses of irradiation. Moreover, irradiation enhanced T cell migration towards OAC patient-derived tumour-conditioned media (TCM). In vitro treatment with the CCR5 antagonist Maraviroc enhanced IFN-γ production by CD4+ T cells and increased the migration of irradiated CD8+ T cells towards irradiated TCM, suggesting its synergistic therapeutic potential in combination with irradiation. Overall, this study highlights the immunostimulatory properties of radiation in promoting anti-tumour T cell responses in OAC and increasing T cell migration towards chemotactic cues in the tumour. Importantly, the CCR5 antagonist Maraviroc holds promise to be repurposed in combination with radiotherapy to promote anti-tumour T cell responses in OAC.

Management of esophageal anastomotic leaks, a systematic review and network meta-analysis.

There is currently no consensus as to how to manage esophageal anastomotic leaks. Intervention with endoscopic vacuum-assisted closure (EVAC), stenting, reoperation, and conservative management have all been mooted as potential options. To conduct a systematic review and network meta-analysis (NMA) to evaluate the optimal management strategy for esophageal anastomotic leaks. A systematic review was performed as per the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines with extension for NMA. NMA was performed using R packages and Shiny. In total, 12 retrospective studies were included, which included 511 patients. Of the 449 patients for whom data regarding sex was available, 371 (82.6%) were male, 78 (17.4%) were female. The average age of patients was 62.6 years (standard deviation 10.2). The stenting cohort included 245 (47.9%) patients. The EVAC cohort included 123 (24.1%) patients. The conservative cohort included 87 (17.0%) patients. The reoperation cohort included 56 (10.9%) patients. EVAC had a significantly decreased complication rate compared to stenting (odds ratio 0.23 95%, confidence interval [CI] 0.09;0.58). EVAC had a significantly lower mortality rate than stenting (odds ratio 0.43, 95% CI 0.21; 0.87). Reoperation was used in significantly larger leaks than stenting (mean difference 14.66, 95% CI 4.61;24.70). The growing use of EVAC as a first-line intervention in esophageal anastomotic leaks should continue given its proven effectiveness and significant reduction in both complication and mortality rates. Surgical management is often necessary for significantly larger leaks and will likely remain an effective option in uncontained leaks with systemic features.

Real-time ex vivo monitoring of NK cell migration toward obesity-associated oesophageal adenocarcinoma following modulation of CX3CR1.

Oesophagogastric adenocarcinomas (OAC) are poor prognosis, obesity-associated cancers which may benefit from natural killer (NK) cell-based immunotherapies. Cellular immunotherapies encounter two key challenges to their success in OAC, namely recruitment to extratumoural tissues such as the omentum at the expense of the tumour and an immunosuppressive tumour microenvironment (TME) which can hamper NK cell function. Herein, we examined approaches to overcome the detrimental impact of obesity on NK cells and NK cell-based immunotherapies. We have demonstrated that NK cells migrate preferentially to the chemotactic signals of OAC patient-derived omentum over tumour in an ex vivo model of immune cell migration. We have identified CX3CR1 modulation and/or tumour chemokine profile remodelling as approaches to skew NK cell migration towards tumour. We also report targetable immunosuppressive facets of the obese OAC TME which dampen NK cell function, in particular cytotoxic capabilities. These data provide insights into approaches to therapeutically overcome key challenges presented by obesity and will inform superior design of NK cell-based immunotherapies for OAC.

Evaluating the Impact of Enhanced Recovery After Surgery Protocols on Surgical Outcomes Following Bariatric Surgery-A Systematic Review and Meta-analysis of Randomised Clinical Trials.

BACKGROUND: Enhanced recovery after surgery (ERAS) programmes are evidence-based care improvement processes for surgical patients, which are designed to decrease the impact the anticipated negative physiological cascades following surgery. AIM: To perform a systematic review and meta-analysis of randomised clinical trials (RCTs) to evaluate the impact of ERAS protocols on outcomes following bariatric surgery compared to standard care (SC). METHODS: A systematic review was performed in accordance with PRISMA guidelines. Meta-analysis was performed using Review Manager version 5.4 RESULTS: Six RCTs including 740 patients were included. The mean age was 40.2 years, and mean body mass index was 44.1 kg/m2. Overall, 54.1% underwent Roux-en-Y gastric bypass surgery (400/740) and 45.9% sleeve gastrectomy (340/700). Overall, patients randomised to ERAS programmes had a significant reduction in nausea and vomiting (odds ratio (OR): 0.42, 95% confidence interval (CI): 0.19-0.95, P = 0.040), intraoperative time (mean difference (MD): 5.40, 95% CI: 3.05-7.77, P < 0.001), time to mobilisation (MD: - 7.78, 95% CI: - 5.46 to - 2.10, P < 0.001), intensive care unit stay (ICUS) (MD: 0.70, 95% CI: 0.13-1.27, P = 0.020), total hospital stay (THS) (MD: - 0.42, 95% CI: - 0.69 to - 0.16, P = 0.002), and functional hospital stay (FHS) (MD: - 0.60, 95% CI: - 0.98 to - 0.22, P = 0.002) compared to those who received SC. CONCLUSION: ERAS programmes reduce postoperative nausea and vomiting, intraoperative time, time to mobilisation, ICUS, THS, and FHS compared to those who received SC. Accordingly, ERAS should be implemented, where feasible, for patients indicated to undergo bariatric surgery. Trial registration International Prospective Register of Systematic Reviews (PROSPERO - CRD42023434492.

Evaluating analgesia strategies in patients who have undergone oesophagectomy-a systematic review and network meta-analysis of randomised clinical trials.

Optimal pain control following esophagectomy remains a topic of contention. The aim was to perform a systematic review and network meta-analysis (NMA) of randomized clinical trials (RCTs) evaluating the analgesia strategies post-esophagectomy. A NMA was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)-NMA guidelines. Statistical analysis was performed using Shiny and R. Fourteen RCTs which included 565 patients and assessed nine analgesia techniques were included. Relative to systemic opioids, thoracic epidural analgesia (TEA) significantly reduced static pain scores at 24 hours post-operatively (mean difference (MD): -13.73, 95% Confidence Interval (CI): -27.01-0.45) (n = 424, 12 RCTs). Intrapleural analgesia (IPA) demonstrated the best efficacy for static (MD: -36.2, 95% CI: -61.44-10.96) (n = 569, 15 RCTs) and dynamic (MD: -42.90, 95% CI: -68.42-17.38) (n = 444, 11 RCTs) pain scores at 48 hours. TEA also significantly reduced static (MD: -13.05, 95% CI: -22.74-3.36) and dynamic (MD: -18.08, 95% CI: -31.70-4.40) pain scores at 48 hours post-operatively, as well as reducing opioid consumption at 24 hours (MD: -33.20, 95% CI: -60.57-5.83) and 48 hours (MD: -42.66, 95% CI: -59.45-25.88). Moreover, TEA significantly shortened intensive care unit (ICU) stays (MD: -5.00, 95% CI: -6.82-3.18) and time to extubation (MD: -4.40, 95% CI: -5.91-2.89) while increased post-operative forced vital capacity (MD: 9.89, 95% CI: 0.91-18.87) and forced expiratory volume (MD: 13.87, 95% CI: 0.87-26.87). TEA provides optimal pain control and improved post-operative respiratory function in patients post-esophagectomy, reducing ICU stays, one of the benchmarks of improved post-operative recovery. IPA demonstrates promising results for potential implementation in the future following esophagectomy.

Evaluating mesh fixation techniques for ventral hernia repair: A systematic review and network meta-analysis of randomised control trials.

INTRODUCTION: There is uncertainty regarding the optimal mesh fixation techniques for laparoscopic ventral and incisional hernia repair. AIM: To perform a systematic review and network meta-analysis of randomised control trials (RCTs) to investigate the advantages and disadvantages associated with absorbable tacks, non-absorbable tacks, non-absorbable sutures, non-absorbable staples, absorbable synthetic glue, absorbable sutures and non-absorbable tacks, and non-absorbable sutures and non-absorbable tacks. METHODS: A systematic review was performed as per PRISMA-NMA guidelines. Odds ratios (ORs) and mean differences (MDs) were extracted to compare the efficacy of the surgical approaches. RESULTS: Nine RCTs were included with 707 patients. Short-term pain was significantly reduced in non-absorbable staples (MD; -1.56, confidence interval (CI); -2.93 to -0.19) and non-absorbable sutures (MD; -1.00, CI; -1.60 to -0.40) relative to absorbable tacks. Recurrence, length of stay, operative time, conversion to open surgery, seroma and haematoma formation were unaffected by mesh fixation technique. CONCLUSION: Short-term post-operative pain maybe reduced by the use of non-absorbable sutures and non-absorbable staples. There is clinical equipoise between each modality in relation to recurrence, length of stay, and operative time.

Potential of damage associated molecular patterns in synergising radiation and the immune response in oesophageal cancer.

BACKGROUND: There is an intimate crosstalk between cancer formation, dissemination, treatment response and the host immune system, with inducing tumour cell death the ultimate therapeutic goal for most anti-cancer treatments. However, inducing a purposeful synergistic response between conventional therapies and the immune system remains evasive. The release of damage associated molecular patterns (DAMPs) is indicative of immunogenic cell death and propagation of established immune responses. However, there is a gap in the literature regarding the importance of DAMP expression in oesophageal adenocarcinoma (OAC) or by immune cells themselves. AIM: To investigate the effects of conventional therapies on DAMP expression and to determine whether OAC is an immunogenic cancer. METHODS: We investigated the levels of immunogenic cell death-associated DAMPs, calreticulin (CRT) and HMGB1 using an OAC isogenic model of radioresistance. DAMP expression was also assessed directly using ex vivo cancer patient T cells (n = 10) and within tumour biopsies (n = 9) both pre and post-treatment with clinically relevant chemo(radio)therapeutics. RESULTS: Hypoxia in combination with nutrient deprivation significantly reduces DAMP expression by OAC cells in vitro. Significantly increased frequencies of T cell DAMP expression in OAC patients were observed following chemo(radio)therapy, which was significantly higher in tumour tissue compared with peripheral blood. Patients with high expression of HMGB1 had a significantly better tumour regression grade (TRG 1-2) compared to low expressors. CONCLUSION: In conclusion, OAC expresses an immunogenic phenotype with two distinct subgroups of high and low DAMP expressors, which correlated with tumour regression grade and lymphatic invasion. It also identifies DAMPs namely CRT and HMGB1 as potential promising biomarkers in predicting good pathological responses to conventional chemo(radio)therapies currently used in the multimodal management of locally advanced disease.

External validation of a nomogram predicting conditional survival after tri-modality treatment of esophageal cancer.

BACKGROUND: A conditional survival nomogram was developed at a single high-volume center to predict 5-year overall survival for esophageal cancer patients after neoadjuvant chemoradiation and esophagectomy. The aim of this study was to externally validate the nomogram in a cohort of patients with esophageal adeno- or squamous cell carcinoma from another high-volume center. METHODS: Consecutive patients with an esophageal adeno- or squamous cell carcinoma who had undergone esophagectomy after being treated with preoperative chemoradiation between 2004 and 2016 were selected from a prospectively maintained institutional database. The level of discrimination for prediction of 5-year overall survival was quantified by Harrell's C statistic. Calibration of the conditional survival nomogram was visualized by plotting predicted 5-year survival and observed 5-year survival for comparison. RESULTS: Of the 296 patients examined, the probability of 5-year overall survival directly after surgery was 45% and increased to 51%, 68%, 78%, and 89% for each additional year survived. The predicted 5-year overall survival differed from the observed survival, with a calibration slope of 0.54, 0.55, 0.59, 0.73, and 1.09 directly after surgery and 1, 2, 3, and 4 years of survival after surgery, respectively. The nomogram's discrimination level for 5-year survival was moderate, with a C statistic of 0.65 compared to the 0.70 reported in the original study. CONCLUSION: The nomogram model has moderate predictive discrimination and accuracy, supporting its applicability to external cohorts to predict conditional survival. Further validation studies should empirically assess the model for predictive performance.

Metformin is a metabolic modulator and radiosensitiser in rectal cancer.

Resistance to neoadjuvant chemoradiation therapy, is a major challenge in the management of rectal cancer. Increasing evidence supports a role for altered energy metabolism in the resistance of tumours to anti-cancer therapy, suggesting that targeting tumour metabolism may have potential as a novel therapeutic strategy to boost treatment response. In this study, the impact of metformin on the radiosensitivity of colorectal cancer cells, and the potential mechanisms of action of metformin-mediated radiosensitisation were investigated. Metformin treatment was demonstrated to significantly radiosensitise both radiosensitive and radioresistant colorectal cancer cells in vitro. Transcriptomic and functional analysis demonstrated metformin-mediated alterations to energy metabolism, mitochondrial function, cell cycle distribution and progression, cell death and antioxidant levels in colorectal cancer cells. Using ex vivo models, metformin treatment significantly inhibited oxidative phosphorylation and glycolysis in treatment naïve rectal cancer biopsies, without affecting the real-time metabolic profile of non-cancer rectal tissue. Importantly, metformin treatment differentially altered the protein secretome of rectal cancer tissue when compared to non-cancer rectal tissue. Together these data highlight the potential utility of metformin as an anti-metabolic radiosensitiser in rectal cancer.

Management Experiences of Post-Gastrectomy Severe Alkaline Reflux Esophagitis.

Alkaline reflux esophagitis is a recognized complication of procedures that compromise the lower esophageal sphincter (LES), including gastrectomy. Incidence of reflux is dependent on the reconstructive procedure, with Roux-en-Y (RY) esophagojejunostomy commonly accepted as the optimal method. The authors report their experience of 5 patients who underwent remedial intervention for severe alkaline reflux esophagitis following gastric cancer surgery, over a 6-year period (2014-2020). Primary diagnoses encompassed 4 gastric adenocarcinomas and 1 gastric neuroendocrine tumor. Four patients previously underwent total gastrectomy and 1 subtotal gastrectomy with RY reconstruction. Onset of postoperative reflux symptoms ranged from 2 weeks to 3 years. Failing medical management, all patients underwent jejunojejunal anastomosis and Roux limb length revision with surgical jejunostomy. At follow-up, 4 out of 5 patients had some degree of symptom resolution and one with unresolved symptoms. The authors report our experience of managing this complication following gastrectomy with jejunojejunal anastomosis and Roux limb length revision.

Impact of the Surgical Approach for Neoadjuvantly Treated Gastroesophageal Junction Type II Tumors: A Multinational, High-volume Center Retrospective Cohort Analysis.

OBJECTIVE: The aim of this study was to explore oncologic outcomes of transhiatal gastrectomy (THG) or transthoracic esophagectomy (TTE) for neoadjuvantly treated gastroesophageal junction (GEJ) Siewert type II adenocarcinomas, a multinational, high-volume center cohort analysis was undertaken. BACKGROUND: Neoadjuvant radiochemotherapy or perioperative chemotherapy (CTx) followed by surgery is the standard therapy for locally advanced GEJ. However, the optimal surgical approach for type II GEJ tumors remains unclear, as the decision is mainly based on individual experience and assessment of operative risk. METHODS: A retrospective analysis of 5 prospectively maintained databases was conducted. Between 2012 and 2021, 800 patients fulfilled inclusion criteria for type II GEJ tumors and neoadjuvant radiochemotherapy or CTx. The primary endpoint was median overall survival (mOS). Propensity score matching was performed to minimize selection bias. RESULTS: Patients undergoing THG (n=163, 20.4%) had higher American Society of Anesthesiologists (ASA) classification and cT stage ( P <0.001) than patients undergoing TTE (n=637, 79.6%). Neoadjuvant therapy was different as the THG group were mainly undergoing CTx (87.1%, P <0.001). The TTE group showed higher tumor regression ( P =0.009), lower ypT/ypM categories (both P <0.001), higher nodal yield ( P =0.009) and higher R0 resection rate ( P =0.001). The mOS after TTE was longer (78.0 vs 40.0 months, P =0.013). After propensity score matching a higher R0 resection rate ( P =0.004) and mOS benefit after TTE remained ( P =0.04). Subgroup analyses of patients without distant metastasis ( P =0.037) and patients only after neoadjuvant chemotherapy ( P =0.021) confirmed the survival benefit of TTE. TTE was an independent predictor of longer survival. CONCLUSION: Awaiting results of the randomized CARDIA trial, TTE should in high-volume centers be considered the preferred approach due to favorable oncologic outcomes.

Evaluating the oncological safety of neoadjuvant chemotherapy in locally advanced colon carcinoma: a systematic review and meta-analysis of randomised clinical trials and propensity-matched studies.

PURPOSE: Use of neoadjuvant chemotherapy (NAC) for locally advanced colon cancer (LACC) remains controversial. An integrated analysis of data from high-quality studies may inform the long-term safety of NAC for this cohort. Our aim was to perform a systematic review and meta-analysis of randomised clinical trials (RCTs) and propensity-matched studies to assess the oncological safety of NAC in patients with LACC. METHODS: A systematic review was performed as per preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Survival was expressed as hazard ratios using time-to-effect generic inverse variance methodology, while surgical outcomes were expressed as odds ratios (ORs) using the Mantel-Haenszel method. Data analysis was performed using Review Manager version 5.4. RESULTS: Eight studies (4 RCTs and 4 retrospective studies) including 31,047 patients with LACC were included. Mean age was 61.0 years (range: 19-93 years) and mean follow-up was 47.6 months (range: 2-133 months). Of those receiving NAC, 4.6% achieved a pathological complete response and 90.6% achieved R0 resection (versus 85.9%, P < 0.001). At 3 years, patients receiving NAC had improved disease-free survival (DFS) (OR: 1.28, 95% confidence interval (CI): 1.02-1.60, P = 0.030) and overall survival (OS) (OR: 1.76, 95% CI: 1.10-2.81, P = 0.020). When using time-to-effect modelling, a non-significant difference was observed for DFS (HR: 0.79, 95% CI: 0.57-1.09, P = 0.150) while a significant difference in favour of NAC was observed for OS (HR: 0.75, 95% CI: 0.58-0.98, P = 0.030). CONCLUSION: This study highlights the oncological safety of NAC for patients being treated with curative intent for LACC using RCT and propensity-matched studies only. These results refute current management guidelines which do not advocate for NAC to improve surgical and oncological outcomes in patients with LACC. TRIAL REGISTRATION: International Prospective Register of Systematic Review (PROSPERO) registration: CRD4202341723.

PD-1 blockade attenuates surgery-mediated immunosuppression and boosts Th1 immunity perioperatively in oesophagogastric junctional adenocarcinoma.

Introduction: This timely study assesses the immunosuppressive effects of surgery on cytotoxic Th1-like immunity and investigates if immune checkpoint blockade (ICB) can boost Th1-like immunity in the perioperative window in upper gastrointestinal cancer (UGI) patients. Methods: PBMCs were isolated from 11 UGI patients undergoing tumour resection on post-operative days (POD) 0, 1, 7 and 42 and expanded ex vivo using anti-CD3/28 and IL-2 for 5 days in the absence/presence of nivolumab or ipilimumab. T cells were subsequently immunophenotyped via flow cytometry to determine the frequency of T helper (Th)1-like, Th1/17-like, Th17-like and regulatory T cell (Tregs) subsets and their immune checkpoint expression profile. Lymphocyte secretions were also assessed via multiplex ELISA (IFN-γ, granzyme B, IL-17 and IL-10). The 48h cytotoxic ability of vehicle-, nivolumab- and ipilimumab-expanded PBMCs isolated on POD 0, 1, 7 and 42 against radiosensitive and radioresistant oesophageal adenocarcinoma tumour cells (OE33 P and OE33 R) was also examined using a cell counting kit-8 (CCK-8) assay to determine if surgery affected the killing ability of lymphocytes and whether the use of ICB could enhance cytotoxicity. Results: Th1-like immunity was suppressed in expanded PBMCs in the immediate post-operative setting. The frequency of expanded circulating Th1-like cells was significantly decreased post-operatively accompanied by a decrease in IFN-γ production and a concomitant increase in the frequency of expanded regulatory T cells with an increase in circulating levels of IL-10. Interestingly, PD-L1 and CTLA-4 immune checkpoint proteins were also upregulated on expanded Th1-like cells post-operatively. Additionally, the cytotoxic ability of expanded lymphocytes against oesophageal adenocarcinoma tumour cells was abrogated post-surgery. Of note, the addition of nivolumab or ipilimumab attenuated the surgery-mediated suppression of lymphocyte cytotoxicity, demonstrated by a significant increase in tumour cell killing and an increase in the frequency of Th1-like cells and Th1 cytokine production. Conclusion: These findings support the hypothesis of a surgery-mediated suppression in Th1-like cytotoxic immunity and highlights a rationale for the use of ICB within the perioperative setting to abrogate tumour-promoting effects of surgery and ameliorate the risk of recurrence.