This article highlights the importance of considering Cognitive Load (CL) and Cognitive Load Theory (CLT) during surgical training, focusing on the acquisition of intra-operative skills. It describes the basis of CLT with the overarching aim of describing CLT-based techniques to enhance current training strategies and surgical performance, many of which are instinctively already employed in surgical practice. Currently, methods of feedback and assessment are imperfect - typically subjective, unsystematic, opportunistic, or retrospective, and at risk of human bias. Surgical Sabermetrics, the advanced analytics of surgical and audio-visual data, aims to enhance this feedback by providing objective, real-time, digital-based feedback. This article introduces the benefit of real-time measurement of CL to enhance feedback and its applications to surgical performance that follow the ethos of Surgical Sabermetrics.¹ The 2022 theme for ICOSET was "Making it Better." Cognitive Load and Surgical Sabermetrics principles provide tools to make Surgical training better, with the goal of higher quality care for patients.

Cancer cachexia is a major cause of patient morbidity and mortality, with no efficacious treatment or management strategy. Despite cachexia sharing pathophysiological features with a number of neuromuscular wasting conditions, including age-related sarcopenia, the mechanisms underlying cachexia remain poorly understood. Studies of related conditions suggest that pathological targeting of the neuromuscular junction (NMJ) may play a key role in cachexia, but this has yet to be investigated in human patients. Here, high-resolution morphological analyses were undertaken on NMJs of rectus abdominis obtained from patients undergoing upper GI cancer surgery compared with controls (N = 30; n = 1,165 NMJs). Cancer patients included those with cachexia and weight-stable disease. Despite the low skeletal muscle index and significant muscle fiber atrophy (P < 0.0001) in patients with cachexia, NMJ morphology was fully conserved. No significant differences were observed in any of the pre- and postsynaptic variables measured. We conclude that NMJs remain structurally intact in rectus abdominis in both cancer and cachexia, suggesting that denervation of skeletal muscle is not a major driver of pathogenesis. The absence of NMJ pathology is in stark contrast to what is found in related conditions, such as age-related sarcopenia, and supports the hypothesis that intrinsic changes within skeletal muscle, independent of any changes in motor neurons, represent the primary locus of neuromuscular pathology in cancer cachexia.

Significant variation exists in the outcomes used in cancer cachexia trials, including measures of body composition, which are often selected as primary or secondary endpoints. To date, there has been no review of the most commonly selected measures or their potential sensitivity to detect changes resulting from the interventions being examined. The aim of this systematic review is to assess the frequency and diversity of body composition measures that have been used in cancer cachexia trials. MEDLINE, Embase and Cochrane Library databases were systematically searched between January 1990 and June 2021. Eligible trials examined adults (≥18 years) who had received an intervention aiming to treat or attenuate the effects of cancer cachexia for >14 days. Trials were also of a prospective controlled design and included body weight or at least one anthropometric, bioelectrical or radiological endpoint pertaining to body composition, irrespective of the modality of intervention (e.g., pharmacological, nutritional, physical exercise and behavioural) or comparator. Trials with a sample size of <40 patients were excluded. Data extraction used Covidence software, and reporting followed the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidance. This review was prospectively registered (PROSPERO: CRD42022276710). A total of 84 clinical trials, comprising 13 016 patients, were eligible for inclusion. Non‐small‐cell lung cancer and pancreatic cancer were studied most frequently. The majority of trial interventions were pharmacological (52%) or nutritional (34%) in nature. The most frequently reported endpoints were assessments of body weight (68 trials, n = 11 561) followed by bioimpedance analysis (BIA)‐based estimates (23 trials, n = 3140). Sixteen trials (n = 3052) included dual‐energy X‐ray absorptiometry (DEXA)‐based endpoints, and computed tomography (CT) body composition was included in eight trials (n = 841). Discrepancies were evident when comparing the efficacy of interventions using BIA‐based estimates of lean tissue mass against radiological assessment modalities. Body weight, BIA and DEXA‐based endpoints have been most frequently used in cancer cachexia trials. Although the optimal endpoints cannot be determined from this review, body weight, alongside measurements from radiological body composition analysis, would seem appropriate. The choice of radiological modality is likely to be dependent on the trial setting, population and intervention in question. CT and magnetic resonance imaging, which have the ability to accurately discriminate tissue types, are likely to be more sensitive and provide greater detail. Endpoints are of particular importance when aligned with the intervention's mechanism of action and/or intended patient benefit.

Opinion statement: Considerable advances in the investigation and management of oesophagogastric cancer have occurred over the last few decades. While the historically dismal prognosis associated with these diseases has improved, outcomes remain very poor. Cancer cachexia is an often neglected, yet critical, factor for this patient group. There is a persuasive argument that a lack of assessment and treatment of cachexia has limited progress in oesophagogastric cancer care. In the curative setting, the stage of the host (based on factors such as body composition, function, and inflammatory status), alongside tumour stage, has the potential to influence treatment efficacy. Phenotypical features of cachexia may decrease the survival benefit of (peri-operative) chemoradiotherapy, immunotherapy, or surgical resection in patients with potentially curative malignancy. Most patients with oesophagogastric cancer unfortunately present with disease which is not amenable, or is unlikely to respond, to these treatments. In the palliative setting, host factors can similarly impair results from systemic anti-cancer therapies, cause adverse symptoms, and reduce quality of life. To optimise treatment pathways and enhance patient outcomes, we must utilise this information during clinical decision-making. As our understanding of the genesis of cancer cachexia improves and more therapeutic options, ranging from basic (e.g. exercise and nutrition) to targeted (e.g. anti-IL1 α and anti-GDF-15), become available, there can be grounds for optimism. Cachexia can change from a hitherto neglected condition to an integral part of the oesophagogastric cancer treatment pathway.

Cachexia is a multifactorial wasting syndrome associated with high morbidity and mortality in patients with cancer. Diagnosis can be difficult and, in the clinical situation, usually relies upon reported weight loss. The ‘omics’ technologies allow us the opportunity to study the end points of many biological processes. Among these, blood-based metabolomics is a promising method to investigate the pathophysiology of human cancer cachexia and identify candidate biomarkers. In this study, we performed liquid chromatography mass spectrometry (LC/MS)-based metabolomics to investigate the metabolic profile of cancer-associated weight loss. Non-selected patients undergoing surgery with curative intent for upper gastrointestinal cancer were recruited. Fasting plasma samples were taken at induction of anaesthesia. LC/MS analysis showed that 6 metabolites were highly discriminative of weight loss. Specifically, a combination profile of LysoPC 18.2, L-Proline, Hexadecanoic acid, Octadecanoic acid, Phenylalanine and LysoPC 16:1 showed close correlation for eight weight-losing samples (≥5% weight loss) and nine weight-stable samples (<5%weight loss) between predicted and actual weight change (r = 0.976, p = 0.0014). Overall, 40 metabolites were associated with ≥5% weight loss. This study provides biological validation of the consensus definition of cancer cachexia (Fearon et al.) and provides feasible candidate markers for further investigation in early diagnosis and the assessment of therapeutic intervention.

Cancer cachexia is not purely an end-stage phenomenon and can influence the outcomes of patients with potentially curable disease. This review examines the effect of pre-treatment cachexia on overall survival, in patients undergoing surgical resection of oesophagogastric cancer. A systematic literature search of MEDLINE, EMBASE and Cochrane Library databases was conducted, from January 2000 to May 2022, to identify studies reporting the influence of cachexia on patients undergoing an oesophagogastric resection for cancer with curative intent. Meta-analyses of the primary (overall survival) and secondary (disease-free survival and postoperative mortality) outcomes were performed using random-effects modelling. Meta-regression was used to examine disease stage as a potential confounder. Ten non-randomized studies, comprising 7186 patients, were eligible for inclusion. The prevalence of pre-treatment cachexia was 35 per cent (95 per cent c.i.: 24–47 per cent). Pooled adjusted hazard ratios showed that cachexia was adversely associated with overall survival (HR 1.46, 95 per cent c.i.: 1.31–1.60, P < 0.001). Meta-analysis of proportions identified decreased overall survival at 1-, 3- and 5-years in cachectic cohorts. Pre-treatment cachexia was not a predictor of disease-free survival and further data are required to establish its influence on postoperative mortality. The proportion of patients with stage III/IV disease was a significant moderator of between-study heterogeneity. Cachexia may have a greater influence on overall survival in studies where more patients have a locally advanced malignancy. Pre-treatment cachexia adversely influences overall survival following resection of an oesophagogastric malignancy.