Integrating Patient-Reported Outcomes Into Prognostication in Gastroesophageal Cancer: Results of a Population-Based Retrospective Cohort Analysis.

BACKGROUND: Patient-reported outcomes measures (PROM) are self-reflections of an individual's physical functioning and emotional well-being. The Edmonton Symptom Assessment Scale (ESAS) is a simple and validated PRO tool of 10 common symptoms and a patient-reported functional status (PRFS) measure. The prognostic value of this tool is unknown in patients with gastroesophageal cancer (GEC). In this study, we examined the association between the ESAS score and overall survival (OS) in patients with GEC, the prognostication difference between ESAS and Eastern Cooperative Oncology Group (ECOG), and assessed the correlation between PRFS and the physician-reported ECOG performance status (PS). METHODS: The study was a retrospective cohort study of 211 patients with GEC with localized (stages I-III) and metastatic disease who completed at least one baseline ESAS prior to treatment. Patients were grouped into 3 cohorts based on ESAS score. OS was assessed using the Kaplan-Meier method, and the concordance index (c-index) was calculated for ESAS and physician-reported ECOG. The agreement between PRFS and physician-ECOG was also assessed. RESULTS: In total, 211 patients were included. The median age was 60.8 years; 90% of patients were ECOG PS 0-1; 38% of patients were stages I-III, while 62% were de novo metastatic patients. Median OS in low, moderate, high symptom burden (SB) patients' cohorts was 19.17 m, 16.39 mm, and 12.68 m, respectively (P < .04). The ability to predict death was similar between physician-ECOG and ESAS (c-index 0.56 and 0.5753, respectively) and PRFS and physician-ECOG (c-index of 0.5615 and 0.5545, respectively). The PS agreement between patients and physicians was 50% with a weighted Kappa of 0.27 (95% CI: 0.17-0.38). CONCLUSION: Patient's SB seems to carry a prognostic significance. ESAS and physician-reported ECOG exhibit comparable prognostic values. Physicians and patients can frequently have divergent opinions on PS. ESAS takes a patient-centered approach and should be encouraged in practice among patients with GEC as an additional tool for prognostication.

Comparison of Four Clinical Prognostic Scores in Patients with Advanced Gastric and Esophageal Cancer.

BACKGROUND: Prognostic scores that can identify patients at risk for early death are needed to aid treatment decision-making and patient selection for clinical trials. We compared the accuracy of four scores to predict early death (within 90 days) and overall survival (OS) in patients with metastatic gastric and esophageal (GE) cancer. METHODS: Advanced GE cancer patients receiving first-line systemic therapy were included. Prognostic risks were calculated using: Royal Marsden Hospital (RMH), MD Anderson Cancer Centre (MDACC), Gustave Roussy Immune (GRIm-Score), and MD Anderson Immune Checkpoint Inhibitor (MDA-ICI) scores. Overall survival (OS) was estimated using the Kaplan-Meier method. Cox proportional hazards models were used to analyze associations between prognostic scores and OS. The predictive discrimination was estimated using Harrell's c-index. Predictive ability for early death was measured using time-dependent AUCs. RESULTS: In total, 451 patients with metastatic GE cancer were included. High risk patients had shorter OS for all scores (RMH high- vs. low-risk median OS 7.9 vs. 12.2 months, P < .001; MDACC 6.8 vs. 11.9 months P < .001; GRIm-Score 5.3 vs. 13 months, P < .001; MDA-ICI 8.2 vs. 12.2 months, P < .001). On multivariable analysis, each prognostic score was significantly associated with OS. The GRIm-Score had the highest predictive discrimination and predictive ability for early death. CONCLUSIONS: The GRIm-Score had the highest accuracy in predicting early death and OS. Clinicians may use this score to identify patients at higher risk of early death to guide treatment decisions including clinical trial enrolment. This score could also be used as a stratification factor in future clinical trial designs.

Desmoid Tumors in Familial Adenomatous Polyposis Patients: Favorable Outcomes with Multidisciplinary Management.

OBJECTIVE: In this study, we aimed to describe the clinical features, management, and outcomes of desmoid tumors (DTs) in familial adenomatous polyposis (FAP) patients at a high-volume sarcoma center. METHODS: Consecutive patients with FAP and DTs were identified from our institutional databases (1985-2021). Patient demographics, treatment, and outcomes were described. Categorical data were compared using Fisher's exact test, and Kaplan-Meier curves were used to estimate progression-free survival (PFS). RESULTS: Forty-five patients with 67 DTs were identified: 39 mesenteric or retroperitoneal (58.2%), 17 abdominal wall (25.4%), 4 extremity (6%), 4 breast (6%) and 3 back (4.4%). Severe DT symptoms were present in 12 patients (26.7%). Initial treatments per tumor were observation in 30 (44.8%) DTs, chemotherapy in 15 (22.4%) DTs, surgery in 10 (14.9%) DTs, and other systemic therapies in 10 (14.9%) DTs. The majority of DTs remained stable with observation or a single intervention (77.8%). Median PFS was 23.4 years (95% confidence interval 7.6-39.2). In the 12 severely symptomatic patients, four patients required more than two interventions for DT control. At a median follow-up of 6.0 years (range 0.7-35.8 years), 33 (73.3%) patients were alive with disease, 7 (15.6%) were alive without disease, and 5 (11.1%) died of other causes. No patients died of DT-related complications. CONCLUSIONS: The majority of DTs in FAP patients remained stable with observation or a single intervention. There were no DT-related deaths; however, 12 of 45 patients (26.7%) experienced significant tumor morbidity and required more interventions for disease control. Further studies on quality of life are required.

Profiles of Burnout and Response to the COVID-19 Pandemic Among General Surgery Residents at a Large Academic Training Program.

BACKGROUND: COVID-19 has placed demands on General Surgery residents, who are already at high risk of burnout. This study examined the pandemic's impact on burnout and wellness among General Surgery residents at a large training program. METHODS: General Surgery residents at our institution completed a survey focused on self-reported burnout, mental health, perceptions of wellness resources, and changes in activities during the pandemic. Burnout was measured using the Maslach Burnout Inventory (MBI). Unsupervised machine learning (k-means clustering) was used to identify profiles of burnout and comparisons between profiles were made. RESULTS: Of 82 eligible residents, 51 completed the survey (62% response rate). During COVID-19, 63% of residents had self-described burnout, 43% had depression, 18% acknowledged binge drinking/drug use, and 8% had anxiety. There were no significant differences from pre-pandemic levels (p all >.05). Few residents perceived available wellness resources as effective (6%). Based on MBI scores, the clustering analysis identified three clusters, characterized as "overextended", "engaged", and "ineffective". Engaged residents had the least concerning MBI scores and were significantly more likely to exercise, retain social contact during the pandemic, and had less self-reported anxiety or depression. Research residents were overrepresented in the ineffective cluster (46%), which had high rates of self-reported burnout (77%) and was characterized by the lowest personal accomplishment scores. Rates of self-reported burnout for overextended and engaged residents were 73% and 48%, respectively. CONCLUSION: Surgical residents have high rates of self-reported burnout and depression during the COVID-19 pandemic. Clusters of burnout may offer targets for individualized intervention.

Effect of Preoperative Treatment on the Performance of Predictive Nomograms in Primary Retroperitoneal Sarcoma.

BACKGROUND: Retroperitoneal sarcoma (RPS)-specific nomograms provide estimates of survival and recurrence risk following resection in the individual patient. The effect of preoperative treatment on nomogram performance has not been previously examined. Our aim was to evaluate the predictive accuracy of existing RPS-specific nomograms in patients managed at our center, where the majority of patients received preoperative radiation. PATIENTS AND METHODS: All patients who underwent curative treatment for primary RPS at Mount Sinai Hospital/Princess Margaret Hospital between 1996 and 2016 were identified. The performance of four previously published nomograms was assessed by measuring the agreement between nomogram-predicted and observed outcomes using Harrell's C-Index and level of calibration. Outcomes included in each of the nomograms [overall survival (OS), disease-free survival (DFS), disease-specific death (DSD), local recurrence (LR), distant recurrence (DR)] at each of the specified post-resection timepoints were examined. RESULTS: In total, 253 patients were included. When observed outcomes were compared with those predicted by each of the four nomograms, the C-Index ranged from 0.60 to 0.81, representing a wide range of predictive accuracy. The lowest C-Index was for prediction of LR. Calibration plots revealed that the Memorial Sloan Kettering Cancer Center (MSKCC) nomogram predicted a 5-year LR of 45%, whereas the observed LR was 24%. Overprediction of LR was detected in patients who had undergone preoperative radiotherapy, but not in patients treated with surgery alone. CONCLUSIONS: Preoperative radiotherapy appeared to preclude the use of the LR component of existing nomograms for primary RPS. Updated nomograms should be created to reflect this variable, particularly in light of the recently published STRASS trial results.

Preoperative and Postoperative Approaches to Gastroesophageal Cancer: What is All the Fuss About.

Gastroesophageal cancers carry poor prognoses, and are a leading cause of cancer-related morbidity and mortality worldwide. Even in those with resectable disease, more than half of patients treated with surgery alone experience disease recurrence. Multimodality approaches using preoperative and postoperative chemotherapy and/or radiotherapy have been established, resulting in incremental improvements in outcomes. Globally, there is no standardized approach, and treatment varies with geographic location. The question remains of how to select the optimal perioperative treatment that will maximize benefit for patients while avoiding toxicities from unnecessary therapies. This article reviews currently available evidence supporting preoperative and postoperative therapy in gastroesophageal cancers, with an emphasis on recent practice-changing trials and ongoing areas of investigation, including the role of immune checkpoint inhibition and biomarker-guided treatment.

Surgical trainees achieving the CanMEDS roles in the COVID-19 era: What have we learned and where do we go?

SummaryThe COVID-19 pandemic has substantially changed the practice of medicine with a shift to virtual clinical encounters, alternative management of surgical diseases owing to restrictions on elective operations, and physician redeployment to other medical services requiring coverage. These changes may limit opportunities for trainees to gain surgical expertise and have the potential to drastically affect postgraduate surgical education. However, the pandemic has also created a number of opportunities to navigate these challenges and enhance how surgical education is delivered. For example, there are now more learning opportunities available to trainees because of virtual educational sessions. We highlight some considerations in adapting postgraduate surgical training to achieve competency in the CanMEDS roles in the COVID-19 era.

Chemoradiotherapy Using Carboplatin plus Paclitaxel versus Cisplatin plus Fluorouracil for Esophageal or Gastroesophageal Junction Cancer.

BACKGROUND: Trimodality therapy (TMT) with neoadjuvant chemoradiotherapy (nCRT) using concurrent carboplatin plus paclitaxel (CP) followed by surgery is the standard of care for locoregional esophageal or gastroesophageal junction (GEJ) cancers. Alternatively, nCRT with cisplatin plus fluorouracil (CF) can be used. Definitive chemoradiotherapy (dCRT) with CP or CF can be used if surgery is not planned. In the absence of comparative trials, we aimed to evaluate outcomes of CP and CF in the settings of TMT and dCRT. METHODS: A single-site, retrospective cohort study was conducted at the Princess Margaret Cancer Centre to identify all patients who received CRT for locoregional esophageal or GEJ cancer. Overall survival (OS) and disease-free survival (DFS) were assessed using the Kaplan-Meier method and multivariable Cox regression model. The inverse probability treatment weighting (IPTW) method was used for sensitivity analysis. RESULTS: Between 2011 and 2015, 93 patients with esophageal (49%) and GEJ (51%) cancers underwent nCRT (n = 67; 72%) or dCRT (n = 26; 28%). Median age was 62.3 years and 74% were male. Median follow-up was 23.9 months. Comparing CP to CF in the setting of TMT, the OS and DFS rates were similar. In the setting of dCRT, CP was associated with significantly inferior 3-year OS (36 vs. 63%; p = 0.001; HR 3.1; 95% CI: 1.2-7.7) and DFS (0 vs. 41%; p = 0.004; HR 3.6; 95% CI: 1.4-8.9) on multivariable and IPTW sensitivity analyses. CONCLUSIONS: TMT with CF and CP produced comparable outcomes. However, for dCRT, CF may be a superior regimen.

The accuracy of three predictive models in the evaluation of recurrence rates for gastrointestinal stromal tumors.

BACKGROUND: Treatment decisions for gastrointestinal stromal tumors (GIST) are frequently guided by tumor characteristics. An accurate prediction of recurrence is important to determine the benefit from targeted therapy. Our goal was to compare the concordance of three validated risk stratification schemes with observed outcomes in patients undergoing resection for GISTs. METHODS: Patients who underwent surgery for GISTs from 2001 to 2011 at a tertiary centre were identified. Survival was evaluated using the Kaplan-Meier product-limit method. Cox proportional hazard models were used to obtain predicted recurrence for each system and concordance indices were calculated. RESULTS: Of 110 patients identified, 77 (70.0%) had surgery and 29 (26.4%) also received adjuvant therapy. The majority of patients had tumors that were very low (4.5%), low (32.7%), or intermediate (22.7%) in terms of malignant potential. R0 resection was achieved in 89.1% of cases. Observed 2-year and 5-year recurrence rates were significantly lower than those predicted by the Memorial Sloan Kettering Cancer Center nomogram (7.6% vs. 19.3% and 18.4% vs. 27.0%); however, it was the most favorable tool compared to the US National Institutes of Health (NIH)-consensus (P = 0.0017) and modified NIH-consensus (P < 0.001), with a concordance index of 0.811. CONCLUSION: Development of a novel predictive tool that includes additional prognostic factors may better stratify recurrence following resection for GIST.

Improving multidisciplinary cancer conferences: a population-based intervention.

BACKGROUND: Multidisciplinary cancer conferences (MCCs) facilitate the discussion of appropriate diagnostic and treatment options for an individual cancer patient. In 2007, a study conducted in Ontario found that 52 % of hospitals were able to provide access to MCCs. In 2006, Cancer Care Ontario published minimum standards for MCCs. A framework for measurement was developed to monitor MCCs at the hospital, regional, and provincial level. The objective of this study was to review the results from initial efforts to improve quality and access through a population-based intervention. METHODS: Data collection was completed prospectively between October to December in 2009, 2010, and 2011. A criterion satisfaction score (CSS) was developed on the basis of indicators including MCC frequency, type of patient case review, the presence of a chair and coordinator, and the attendance of appropriate medical staff members. For each hospital and region, the overall number of MCCs, patients discussed, and CSSs was calculated. RESULTS: Data were available from 13 of 14 regions in 2009 and all 14 regions in 2010 and 2011. The number of MCCs increased from 660 in 2009 to 798 in 2011 (p = 0.06). The number of patients discussed at MCCs increased from 4,695 in 2009 to 5,702 in 2011 (p = 0.22). The CSS scores across the regions improved significantly across 2009-2011 (p < 0.001). CONCLUSIONS: A population-based intervention has been associated with an improvement in access and quality of MCCs.

Multidisciplinary cancer care: does it improve outcomes?

Multidisciplinary care has been advocated as a solution for increasingly complex treatment decisions in cancer patients. The impact of multidisciplinary care on patient survival has been studied, but evidence is limited by poor methodological quality. Lack of conclusive evidence for increased survival is balanced against improvements in quality of care, guideline adherence, reduction in wait times, and greater satisfaction for patients and care providers.

Combination of clinical, radiomic, and "delta" radiomic features in survival prediction of metastatic gastroesophageal adenocarcinoma.

Objectives: To identify combined clinical, radiomic, and delta-radiomic features in metastatic gastroesophageal adenocarcinomas (GEAs) that may predict survival outcomes. Methods: A total of 166 patients with metastatic GEAs on palliative chemotherapy with baseline and treatment/follow-up (8-12 weeks) contrast-enhanced CT were retrospectively identified. Demographic and clinical data were collected. Three-dimensional whole-lesional radiomic analysis was performed on the treatment/follow-up scans. "Delta" radiomic features were calculated based on the change in radiomic parameters compared to the baseline. The univariable analysis (UVA) Cox proportional hazards model was used to select clinical variables predictive of overall survival (OS) and progression-free survival (PFS) (p-value <0.05). The radiomic and "delta" features were then assessed in a multivariable analysis (MVA) Cox model in combination with clinical features identified on UVA. Features with a p-value <0.01 in the MVA models were selected to assess their pairwise correlation. Only non-highly correlated features (Pearson's correlation coefficient <0.7) were included in the final model. Leave-one-out cross-validation method was used, and the 1-year area under the receiver operating characteristic curve (AUC) was calculated for PFS and OS. Results: Of the 166 patients (median age of 59.8 years), 114 (69%) were male, 139 (84%) were non-Asian, and 147 (89%) had an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1. The median PFS and OS on treatment were 3.6 months (95% CI 2.86, 4.63) and 9 months (95% CI 7.49, 11.04), respectively. On UVA, the number of chemotherapy cycles and number of lesions at the end of treatment were associated with both PFS and OS (p < 0.001). ECOG status was associated with OS (p = 0.0063), but not PFS (p = 0.054). Of the delta-radiomic features, delta conventional HUmin, delta gray-level zone length matrix (GLZLM) GLNU, and delta GLZLM LGZE were incorporated into the model for PFS, and delta shape compacity was incorporated in the model for OS. Of the treatment/follow-up radiomic features, shape compacity and neighborhood gray-level dependence matrix (NGLDM) contrast were used in both models. The combined 1-year AUC (Kaplan-Meier estimator) was 0.82 and 0.81 for PFS and OS, respectively. Conclusions: A combination of clinical, radiomics, and delta-radiomic features may predict PFS and OS in GEAs with reasonable accuracy.

Clinico-demographic characteristics and outcomes of radiation-induced sarcomas (RIS): a CanSaRCC study.

Background: Radiation-induced sarcomas (RIS) tend to have aggressive behaviour and because of their rarity, the most appropriate management for these malignancies is uncertain. Objectives: Using the Canadian Sarcoma Research and Clinical Collaboration (CanSaRCC) database, a national sarcoma registry, we aimed to investigate prognostic factors and outcomes for RIS. Design: Retrospective study of RIS patients treated from 1996 to 2021 at three Canadian centres. Methods: RIS was defined as a sarcoma arising in a previously irradiated field following a 3+ year latency period, whose histology was distinct from the initially irradiated tumour. Clinicopathologic and treatment-related information was extracted from the CanSaRCC database. Overall survival (OS) was defined as the time from RIS diagnosis to death from any cause. Response rate (RR) to neoadjuvant chemotherapy (NACT) was based on physician assessment. Time-to-event analyses were estimated using the Kaplan-Meier method, with Cox regression for multivariate analysis. We considered a two-tailed p-value of <0.05 as statistically significant. Results: One hundred seven tumours met the criteria for RIS and were divided into three subgroups: breast angiosarcoma (BAS, n = 54), osteosarcoma (OST, n = 16), and other soft-tissue sarcomas (STS, n = 37). Patients were mostly female (n = 85, 79%), treated initially for breast carcinomas (n = 54, 50.5%), and diagnosed with high-grade tumours (n = 61/71, 86%). None had evidence of synchronous metastasis. Patients with OST were younger (median age: 48 years, p < 0.001), and BAS had the shortest latency interval (8 versus 18 years for OST/STS, p < 0.001). Most patients underwent surgery, 76% (n = 76/100) R0; 24% (n = 26) received radiation therapy, mostly (n = 15, 57.7%) neoadjuvant. Among those receiving chemotherapy, 30 (75%) underwent NACT; among patients with documented response assessment, the RR was 68% (n = 17/25), being even higher in the BAS population (89.5%, n = 13/17). Median OS was 53 months (95% CI 34-101), with a 5-year OS of 47.6%; larger tumour size, high histologic grade and older age were independent prognostic factors for worse OS. Conclusion: Surgery is standard, and NACT might be useful to downsize large lesions, especially in BAS patients. Raising RIS awareness is fundamental to promoting appropriate management and fostering research through multi-institutional collaborations.

Surgical management of gastric perforation in the setting of gastric cancer.

BACKGROUND: Gastric perforation is a rare presentation of gastric cancer and is thought to be a predictor of advanced disease and, thus, poor prognosis. Guidelines do not exist for the optimal management strategy. We aimed to identify, review, and summarize the literature pertaining to perforation in the setting of gastric cancer. METHODS: A qualitative, systematic review of the literature was performed from January 1, 1985, to January 1, 2010. Searches of MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were performed using search terms related to gastric cancer surgery. Abstracts were examined by two independent reviewers and a standardized data collection tool was used to extract relevant data points. Summary tables were created. RESULTS: Nine articles were included. Perforation was reported to occur in fewer than 5% of gastric cancer patients. Preoperative diagnosis of a gastric cancer was rated and occurred in 14-57% of patients in the papers reviewed. Mortality rates for emergency gastrectomy ranged from 0 to 50% and for simple closure procedures the rates ranged from 8 to 100%. Patients able to receive an R0 gastrectomy demonstrated better long-term survival (median 75 months, 50% 5-year) compared with patients who had simple closure procedures. CONCLUSIONS: Gastric cancer patients presenting with a gastric perforation demonstrate improved overall survival with an R0 resection; however, implementation of this management technique is complicated by infrequent preoperative gastric cancer diagnosis, and inability to perform an oncologic resection due to patient instability and intra-abdominal contamination.

A systematic review of spleen and pancreas preservation in extended lymphadenectomy for gastric cancer.

BACKGROUND: The overall prognosis and survival of patients with advanced gastric cancer are generally poor. Extended lymphadenectomy is recommended for patients with advanced gastric cancer; however, splenectomy and distal pancreatectomy performed with an extended lymph node dissection may be associated with increased morbidity and mortality. METHOD: Electronic literature searches were conducted using Medline, Embase, and the Cochrane Central Register of Controlled Trials from 1 January 1998 to 31 December 2009. Studies on gastric carcinoma investigating extended lymphadenectomy with splenectomy and/or pancreaticosplenectomy that reported data on surgical outcomes or survival were selected. RESULTS: Forty studies were included in this review. Decreased complication rates were demonstrated with spleen preservation in two prospective studies and three retrospective studies, and with pancreas preservation in five retrospective studies. No randomized controlled trial showed survival benefit or detriment for preservation of spleen or pancreas in extended lymphadenectomy. Improved survival was demonstrated with spleen preservation in two prospective and eight retrospective studies, and with pancreas preservation in one prospective and four retrospective studies. CONCLUSIONS: Preservation of the spleen and pancreas during extended lymphadenectomy for gastric cancer decreases complications with no clear evidence of improvement or detriment to overall survival.

Multivisceral resection for gastric cancer: a systematic review.

BACKGROUND: The overall prognosis and survival of patients with advanced gastric cancer is generally poor. One of the most powerful predictors of outcomes in gastric cancer surgery is an R0 resection. However, the extent of the required surgical resection and the additional benefit of multivisceral resection (MVR) are controversial. METHODS: Electronic literature searches were conducted using Medline, EMBASE, and the Cochrane Central Register of Controlled Trials from January 1, 1998 to December 31, 2009. All search titles and abstracts were independently rated for relevance by a minimum of two reviewers. RESULTS: Seventeen studies were included in this review. Among the 1343 patients who underwent MVR, overall complication rates ranged from 11.8 to 90.5%. Perioperative mortality was found to be 0-15%. Pathological T4 disease was confirmed in 28.8-89% of patients. R0 resection and extent of nodal involvement were important predictors of survival in patients undergoing MVR. Patient outcomes may also be affected by the number of organs resected. CONCLUSIONS: Gastrectomy with MVR can be safely pursued in patients with locally advanced gastric cancer to achieve an R0 resection. MVR may not be beneficial in patients with extensive nodal disease.

Junior Mentorship Program (JuMP) Start in Surgery-Implications on Trainee Success.

BACKGROUND: Surgical residency, and particularly the early transition years into junior residency or internship, poses great challenges to the trainee, with implications on success, burnout, and attrition. There is increasing recognition of the benefits of mentorship in surgery, however, significant barriers exist in forming these relationships. Peer mentorship also has many additional benefits, though its role in surgical training is limited. The objective of this study was to evaluate the experience following implementation of a formalized peer mentorship program within a large surgical training program. METHODS: Fourteen post-graduate year 1 (PGY1) general surgery residents were each interviewed and voluntarily matched with a post-graduate year 2 (PGY2) general surgery resident at the University of Toronto for the July 2019 to June 2020 academic year. The recommendation was for an initial meet-and-greet, followed by meetings once every 1 to 2 months. Meetings and discussion topics were encouraged, including emphasis on wellness, study skills, team leadership, and an opportunity to share experiences or concerns. A 1-year post-implementation survey was sent out individually to both groups. RESULTS: Twenty-eight general surgery residents were surveyed (14 PGY1s, 14 PGY2s). Seventy percent (11/14) of PGY1s responded, while 50% (7/14) PGY2s responded. Three themes emerged from survey: I) peer mentorship provides multiple benefits, II) similar personalities make for a good peer mentorship pair, III) formal scheduled sessions for mentorship should be implemented into the residency curriculum. CONCLUSIONS: Amongst junior general surgery residents, a formal peer mentorship program provides benefits to both the mentor and mentee. Scheduling difficulties in the absence of structured meetings, and the importance of the mentee-mentor match are key considerations for successful implementation of a mentorship program. Further longitudinal and multicentre studies can be performed to evaluate the long-term impact of these formalized peer mentorship programs on surgical trainee success, including burnout and attrition.

Investigating the mechanisms of peritoneal metastasis in gastric adenocarcinoma using a novel ex vivo peritoneal explant model.

Gastric adenocarcinoma, commonly known as stomach cancer, has a predilection for metastasis to the peritoneum, which portends limited survival. The peritoneal metastatic cascade remains poorly understood, and existing models fail to recapitulate key elements of the interaction between cancer cells and the peritoneal layer. To explore the underlying cellular and molecular mechanisms of peritoneal metastasis, we developed an ex vivo human peritoneal explant model. Fresh peritoneal tissue samples were suspended, mesothelial layer down but without direct contact, above a monolayer of red-fluorescent dye stained AGS human gastric adenocarcinoma cells for 24 h, then washed thoroughly. Implantation of AGS cells within the explanted peritoneum and invasion beyond the mesothelial layer were examined serially using real-time confocal fluorescence microscopy. Histoarchitecture of the explanted peritoneum was preserved over 5 days ex vivo. Both implantation and invasion were suppressed by restoration of functional E-cadherin through stable transfection of AGS cells, demonstrating sensitivity of the model to molecular manipulation. Thus, our ex vivo human peritoneal explant model permits meaningful investigation of the pathways and mechanism that contribute to peritoneal metastasis. The model will facilitate screening of new therapies that target peritoneal dissemination of gastric, ovarian and colorectal cancer.

Perioperative supplemental oxygen in colorectal patients: a meta-analysis.

BACKGROUND: Perioperative supplemental oxygen has been proposed to decrease the incidence of surgical site infection (SSI) in colorectal surgery. A number of randomized controlled trials (RCTs) have been reported with inconsistent results. In addition, relevant clinical outcomes other than SSIs have been collected in these studies and have been equivocal. A meta-analysis of RCTs was performed to elucidate the effects of perioperative supplemental oxygen in colorectal surgery on SSI incidence, mortality, ICU admission, and length of stay. MATERIALS AND METHODS: A literature search of MEDLINE, PubMed, EMBASE, the Cochrane Library, and the Cochrane Clinical Trials Registry was performed in duplicate. In addition, bibliographic searches were performed, and experts were contacted for unpublished data. RCTs involving colorectal patients that included perioperative supplemental oxygen as a treatment arm and defined SSI as an outcome were included. RESULTS: Five studies met inclusion criteria. Using a random-effects model, perioperative supplemental oxygen did not significantly reduce SSIs (OR = 0.69, 95% CI [0.43, 1.10], P = 0.12). However, a significant mortality benefit was observed (OR = 0.18, 95% CI [0.05, 0.69], P = 0.01). There was no significant difference in the rate of ICU admission or length of stay. Tests of heterogeneity were performed, and significant heterogeneity was only present with respect to length of stay. CONCLUSIONS: Perioperative supplemental oxygen in colorectal surgery does not significantly reduce SSI. However, supplemental oxygen appears to confer a mortality benefit, a previously unreported finding. Further RCTs are required to confirm these conclusions.