The microbial composition of pancreatic ductal adenocarcinoma: A systematic review of 16S rRNA gene sequencing.

BACKGROUND: Pancreatic cancer, specifically pancreatic ductal adenocarcinoma (PDAC), continues to pose a significant clinical and scientific challenge. The most significant finding of recent years is that PDAC tumours harbour their specific microbiome, which differs amongst tumour entities and is distinct from healthy tissue. This review aims to evaluate and summarise all PDAC studies that have used the next-generation technique, 16S rRNA gene amplicon sequencing within each bodily compartment. As well as establishing a causal relationship between PDAC and the microbiome. MATERIALS AND METHODS: This systematic review was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. A comprehensive search strategy was designed, and 1727 studies were analysed. RESULTS: In total, 38 studies were selected for qualitative analysis and summarised significant PDAC bacterial signatures. Despite the growing amount of data provided, we are not able to state a universal 16S rRNA gene microbial signature that can be used for PDAC screening. This is most certainly due to the heterogeneity of the presentation of results, lack of available datasets and the intrinsic selection bias between studies. CONCLUSION: Several key studies have begun to shed light on causality and the influence the microbiome constituents and their produced metabolites could play in tumorigenesis and influencing outcomes. The challenge in this field is to shape the available microbial data into targetable signatures. Making sequenced data readily available is critical, coupled with the coordinated standardisation of data and the need for consensus guidelines in studies investigating the microbiome in PDAC.

Unifying considerations and evidence of macrophage activation mosaicism through human CSF1R and M1/M2 genes.

Addressing the mononuclear phagocyte system (MPS) and macrophage M1/M2 activation is important in diagnosing hematological disorders and inflammatory pathologies and designing therapeutic tools. CSF1R is a reliable marker to identify all circulating MPS cells and tissue macrophages in humans using a single surface protein. CSF1R permits the quantification and isolation of monocyte and dendritic cell (DC) subsets in conjunction with CD14, CD16, and CD1c and is stable across the lifespan and sexes in the absence of overt pathology. Beyond cell detection, measuring M1/M2 activation in humans poses challenges due to response heterogeneity, transient signaling, and multiple regulation steps for transcripts and proteins. MPS cells respond in a conserved manner to M1/M2 pathways such as interleukin-4 (IL-4), steroids, interferon-γ (IFNγ), and lipopolysaccharide (LPS), for which we propose an ad hoc modular gene expression tool. Signature analysis highlights macrophage activation mosaicism in experimental samples, an emerging concept that points to mixed macrophage activation states in pathology.

Impact of tertiary lymphoid structures on prognosis and therapeutic response in pancreatic ductal adenocarcinoma.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is known to have a heterogeneous desmoplastic tumour microenvironment (TME) with a large number of immunosuppressive cells. Recently, high B-cell infiltration in PDAC has received growing interest as a potential therapeutic target. METHODS: Our literature review summarises the characteristics of tumour-associated tertiary lymphoid structures (TLSs) and highlight the key studies exploring the clinical outcomes of TLSs in PDAC patients and the direct effect on the TME. RESULTS: The location, density and maturity stages of TLSs within tumours play a key role in determining the prognosis and is a new emerging target in cancer immunotherapy. DISCUSSION: TLS development is imperative to improve the prognosis of PDAC patients. In the future, studying the genetics and immune characteristics of tumour infiltrating B cells and TLSs may lead towards enhancing adaptive immunity in PDAC and designing personalised therapies.

Improving Environmental Sustainability of Operating Theatres: A Systematic Review of Staff Attitudes, Barriers, and Enablers.

OBJECTIVE: To understand views of staff in relation to attitudes, enablers, and barriers to implementation of environmentally sustainable surgery in operating theatres. This will ultimately help in the goal of successfully implementing more sustainable theatres. SUMMARY BACKGROUND: Global healthcare sectors are responsible for 4.4% of greenhouse gas emissions. Surgical operating theatres are resource intensive areas and improvements will be important to meet Net-Zero carbon emissions within healthcare. METHODS: Three databases were searched (Web of Science, Ovid and PubMed), last check January 2024. We included original manuscripts evaluating staff views regarding sustainable operating theatres. The Mixed Methods Appraisal Tool was used for quality appraisal and data analysed using thematic synthesis. RESULTS: 2933 articles were screened and 14 fulfilled inclusion criteria, using qualitative (1), quantitative (2), and mixed methods (11). Studies were undertaken in a variety of clinical (Department of Anaesthesia, Surgery, Otolaryngology, Obstetrics & Gynaecology and Ophthalmology) and geographical settings (Australia, Canada, France, Germany, New Zealand, USA, UK & Ireland,). Across studies there was a lack of evidence exploring enablers to implementation, but barriers mainly related to the following themes: education and awareness, leadership, resistance to change, facilities and equipment, time, and incentive. CONCLUSION: This systematic review identified attitudes and barriers perceived by clinicians towards improving environmental sustainability within operating theatres, which may inform future strategy towards sustainable surgery. Most studies used a survey-design, whereas use of interviews may provide deeper insights. Future work should be extended to wider stakeholders influencing operating theatres. Additionally, implementation studies should be carried out to examine whether barriers do change in practice. This systematic review identified attitudes and barriers perceived by clinicians towards improving environmental sustainability within operating theatres, which may inform future strategy towards sustainable surgery. Most studies used a survey-design, whereas use of interviews may provide deeper insights. Future work should be extended to wider stakeholders influencing operating theatres. Additionally, implementation studies should be carried out to examine whether barriers do change in practice.

Bile Microbiome Signatures Associated with Pancreatic Ductal Adenocarcinoma Compared to Benign Disease: A UK Pilot Study.

Pancreatic ductal adenocarcinoma (PDAC) has a very poor survival. The intra-tumoural microbiome can influence pancreatic tumourigenesis and chemoresistance and, therefore, patient survival. The role played by bile microbiota in PDAC is unknown. We aimed to define bile microbiome signatures that can effectively distinguish malignant from benign tumours in patients presenting with obstructive jaundice caused by benign and malignant pancreaticobiliary disease. Prospective bile samples were obtained from 31 patients who underwent either Endoscopic Retrograde Cholangiopancreatography (ERCP) or Percutaneous Transhepatic Cholangiogram (PTC). Variable regions (V3-V4) of the 16S rRNA genes of microorganisms present in the samples were amplified by Polymerase Chain Reaction (PCR) and sequenced. The cohort consisted of 12 PDAC, 10 choledocholithiasis, seven gallstone pancreatitis and two primary sclerosing cholangitis patients. Using the 16S rRNA method, we identified a total of 135 genera from 29 individuals (12 PDAC and 17 benign). The bile microbial beta diversity significantly differed between patients with PDAC vs. benign disease (Permanova p = 0.0173). The separation of PDAC from benign samples is clearly seen through unsupervised clustering of Aitchison distance. We found three genera to be of significantly lower abundance among PDAC samples vs. benign, adjusting for false discovery rate (FDR). These were Escherichia (FDR = 0.002) and two unclassified genera, one from Proteobacteria (FDR = 0.002) and one from Enterobacteriaceae (FDR = 0.011). In the same samples, the genus Streptococcus (FDR = 0.033) was found to be of increased abundance in the PDAC group. We show that patients with obstructive jaundice caused by PDAC have an altered microbiome composition in the bile compared to those with benign disease. These bile-based microbes could be developed into potential diagnostic and prognostic biomarkers for PDAC and warrant further investigation.

The Role of the Multiparametric MRI LiverMultiScanTM in the Quantitative Assessment of the Liver and Its Predicted Clinical Applications in Patients Undergoing Major Hepatic Resection for Colorectal Liver Metastasis.

Liver biopsy remains the gold standard for the histological assessment of the liver. With clear disadvantages and the rise in the incidences of liver disease, the role of neoadjuvant chemotherapy in colorectal liver metastasis (CRLM) and an explosion of surgical management options available, non-invasive serological and imaging markers of liver histopathology have never been more pertinent in order to assess liver health and stratify patients considered for surgical intervention. Liver MRI is a leading modality in the assessment of hepatic malignancy. Recent technological advancements in multiparametric MRI software such as the LiverMultiScanTM offers an attractive non-invasive assay of anatomy and histopathology in the pre-operative setting, especially in the context of CRLM. This narrative review examines the evidence for the LiverMultiScanTM in the assessment of hepatic fibrosis, steatosis/steatohepatitis, and potential applications for chemotherapy-associated hepatic changes. We postulate its future role and the hurdles it must surpass in order to be implemented in the pre-operative management of patients undergoing hepatic resection for colorectal liver metastasis. Such a role likely extends to other hepatic malignancies planned for resection.

Cancer cell-derived extracellular vesicles activate hepatic stellate cells in colorectal cancer.

Colorectal cancer (CRC) is the 2nd leading cause of cancer-related deaths worldwide, primarily due to the development of metastatic disease. The liver is the most frequently affected site. The metastatic cascade relies on a complex interaction between the immune system, tumor, and distant organs. Communication between the tumor and the metastatic site can be mediated by tumor-derived extracellular vesicles (EVs) and their cargo. The mechanisms underlying this process are starting to be understood through research that has rapidly expanded over the past 15 years. One crucial aspect is the remodeling of the microenvironment at the site of metastasis, which is essential for the formation of a premetastatic niche and the subsequent establishment of metastatic deposits. In the evaluated study, the authors use cellular experiments and a mouse model to investigate how tumour derived extracellular vesicles and their microRNA contents interact with hepatic stellate cells (HSCs). They demonstrate how this may lead to remodelling of the microenvironment and the formation of colorectal liver metastasis using their experimental model. In this mini review, we examine the current evidence surrounding tumour derived EVs and their effect on the tumour microenvironment to highlight potential areas for future research in CRC and other malignancies.

Systematic review of preoperative n-3 fatty acids in major gastrointestinal surgery.

Objectives: Perioperative nutrition aims to replenish nutritional stores before surgery and reduce postoperative complications. 'Immunonutrition' (including omega-3 fatty acids) may modulate the immune system and attenuate the postoperative inflammatory response. Hitherto, immunonutrition has overwhelmingly been administered in the postoperative period-however, this may be too late to provide benefit. Design: A systematic literature search using MEDLINE and EMBASE for randomized controlled trials (RCTs). Setting: Perioperative major gastrointestinal surgery. Participants: Patients undergoing major gastrointestinal surgery. Interventions: Omega-3 fatty acid supplementation commenced in the preoperative period, with or without continuation into postoperative period. Main outcome measures: The effect of preoperative omega-3 fatty acids on inflammatory response and clinical outcomes. Results: 833 studies were identified. After applying inclusion and exclusion criteria, 12 RCTs, involving 1456 randomized patients, were included. Ten articles exclusively enrolled patients with cancer. Seven studies used a combination of EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) as the intervention and five studies used EPA alone. Eight out of 12 studies continued preoperative nutritional support into the postoperative period.Of the nine studies reporting mortality, no difference was seen. Duration of hospitalisation ranged from 4.5 to 18 days with intervention and 3.5 to 23.5 days with control. Omega-3 fatty acids had no effect on postoperative C-reactive protein and the effect on cytokines (including tumor necrosis factor-α, interleukin (IL)-6 and IL-10) was inconsistent. Ten of the 12 studies had low risk of bias, with one study having moderate bias from allocation and blinding. Conclusions: There is insufficient evidence to support routine preoperative omega-3 fatty acid supplementation for major gastrointestinal surgery, even when this is continued after surgery. PROSPERO registration number: CRD42018108333.

Efficacy and accuracy of faecal sampling by a digital rectal examination for faecal immunochemical testing.

AIM: A digital rectal examination (DRE) during routine assessment for patients with abdominal symptoms provides an opportunity to obtain faeces from the glove for faecal immunochemical testing (FIT). Here, we compared sampling via DRE to the standard faecal sampling by patients. METHOD: Patients were recruited to a prospective observational cohort study between July 2019 and March 2020. Patients provided a sample for the FOB Gold Wide® which was compared to a further sample taken at clinic via DRE. Clinicians reported whether they obtained a 'good' sample filling all the grooves, a 'poor' sample filling some of the grooves or no faecal sample. Cohen's kappa was used to compare percentage agreement around a negative threshold of <10 µg haemoglobin/g of faeces. Sensitivity for serious bowel disease (SBD) was calculated. RESULTS: Of 596 patients who underwent attempted DRE sampling, there were 258 (43.3%) 'good' samples, 117 (19.6%) 'poor' samples and 221 (37.1%) with no sample to wipe in the grooves. Cohen's kappa dropped from 0.70 to 0.30 for the 'good' and 'poor' samples, respectively. Of those with DRE samples and definitive diagnostic outcomes, the sensitivity for SBD dropped significantly from 76.0% to 41.7% between 'good' and 'poor' samples, respectively (p = 0.041). CONCLUSIONS: A 'good' sample obtained by DRE provides comparable results to samples obtained by patients. This creates potential benefit in speed and ease of testing for patients. However, not all DRE sampling attempts are successful, and the clinician must be satisfied that enough faeces is obtained to wipe adequately into all grooves.

Protective ileostomy creation after anterior resection of the rectum: Shared decision-making or still subjective?

AIM: The choice of whether to perform protective ileostomy (PI) after anterior resection (AR) is mainly guided by risk factors (RFs) responsible for the development of anastomotic leakage (AL). However, clear guidelines about PI creation are still lacking in the literature and this is often decided according to the surgeon's preferences, experiences or feelings. This qualitative study aims to investigate, by an open-ended question survey, the individual surgeon's decision-making process regarding PI creation after elective AR. METHOD: Fifty four colorectal surgeons took part in an electronic survey to answer the questions and describe what usually led their decision to perform PI. A content analysis was used to code the answers. To classify answers, five dichotomous categories (In favour/Against PI, Listed/Unlisted RFs, Typical/Atypical, Emotions/Non-emotions, Personal experience/No personal experience) have been developed. RESULTS: Overall, 76% of surgeons were in favour of PI creation and 88% considered listed RFs in the question of whether to perform PI. Atypical answers were reported in 10% of cases. Emotions and personal experience influenced surgeons' decision-making process in 22% and 49% of cases, respectively. The most frequently considered RFs were the distance of the anastomosis from the anal verge (96%), neoadjuvant chemoradiotherapy (88%), a positive intraoperative leak test (65%), blood loss (37%) and immunosuppression therapy (35%). CONCLUSION: The indications to perform PI following rectal cancer surgery lack standardization and evidence-based guidelines are required to inform practice. Until then, expert opinion can be helpful to assist the decision-making process in patients who have undergone AR for adenocarcinoma.

What should be included in case report forms? Development and application of novel methods to inform surgical study design: a mixed methods case study in parastomal hernia prevention.

OBJECTIVES: To describe the development and application of methods to optimise the design of case report forms (CRFs) for clinical studies evaluating surgical procedures, illustrated with an example of abdominal stoma formation. DESIGN: (1) Literature reviews, to identify reported variations in surgical components of stoma formation, were supplemented by (2) intraoperative qualitative research (observations, videos and interviews), to identify unreported variations used in practice to generate (3) a 'long list' of items, which were rationalised using (4) consensus methods, providing a pragmatic list of CRF items to be captured in the Cohort study to Investigate the Prevention of parastomal HERnias (CIPHER) study. SETTING: Two secondary care surgical centres in England. PARTICIPANTS: Patients undergoing stoma formation, surgeons undertaking stoma formation and stoma nurses. OUTCOME MEASURES: Successful identification of key CRF items to be captured in the CIPHER study. RESULTS: 59 data items relating to stoma formation were identified and categorised within six themes: (1) surgical approach to stoma formation; (2) trephine formation; (3) reinforcing the stoma trephine with mesh; (4) use of the stoma as a specimen extraction site; (5) closure of other wounds during the procedure; and (6) spouting the stoma. CONCLUSIONS: This study used multimodal data collection to understand and capture the technical variations in stoma formation and design bespoke CRFs for a multicentre cohort study. The CIPHER study will use the CRFs to examine associations between the technical variations in stoma formation and risks of developing a parastomal hernia. TRIAL REGISTRATION NUMBER: ISRCTN17573805.

A Comprehensive Review of the Current and Future Role of the Microbiome in Pancreatic Ductal Adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is expected to become the second most common cause of cancer death in the USA by 2030, yet progress continues to lag behind that of other cancers, with only 9% of patients surviving beyond 5 years. Long-term survivorship of PDAC and improving survival has, until recently, escaped our understanding. One recent frontier in the cancer field is the microbiome. The microbiome collectively refers to the extensive community of bacteria and fungi that colonise us. It is estimated that there is one to ten prokaryotic cells for each human somatic cell, yet, the significance of this community in health and disease has, until recently, been overlooked. This review examines the role of the microbiome in PDAC and how it may alter survival outcomes. We evaluate the possibility of employing microbiomic signatures as biomarkers of PDAC. Ultimately this review analyses whether the microbiome may be amenable to targeting and consequently altering the natural history of PDAC.

Comparison of the QuikRead go® point-of-care faecal immunochemical test for haemoglobin with the FOB Gold Wide® laboratory analyser to diagnose colorectal cancer in symptomatic patients.

OBJECTIVES: Faecal immunochemical testing for haemoglobin (FIT) is used to triage patients for colonic investigations. Point-of-care (POC) FIT devices on the market have limited data for their diagnostic accuracy for colorectal cancer (CRC). Here, a POC FIT device is compared with a laboratory-based FIT system using patient collected samples from the urgent referral pathway for suspected CRC. METHODS: A prospective, observational cohort study. Patients collected two samples from the same stool. These were measured by POC QuikRead go® (Aidian Oy, Espoo, Finland) and laboratory-based FOB Gold Wide® (Sentinel Diagnostics, Italy). Faecal haemoglobin <10 µg haemoglobin/g of faeces was considered as negative. At this threshold, comparisons between the two systems were made by calculating percentage agreement and Cohen's kappa coefficient. Proportion of negative results were compared with Chi squared testing. Sensitivities for CRC were calculated. RESULTS: A total of 629 included patients provided paired samples for FIT to compare the QuikRead go® and FOB Gold Wide®. The agreement around the negative threshold was 83.0% and Cohen's kappa coefficient was 0.54. The QuikRead go® reported 440/629 (70.0% of samples) as negative compared to 523/629 (83.1%) for the FOB Gold Wide®, this difference was significant (p-value<0.001). Sensitivities for CRC detection by the QuikRead go® and FOB Gold Wide® were 92.9% (95% confidence interval (CI): 68.5-98.7%) and 100% (CI: 78.5-100%) respectively. CONCLUSIONS: Both systems were accurate in their ability to detect CRC. Whilst good agreement around the negative threshold was identified, more patients would be triaged to further colonic investigation if using the QuikRead go®.

Laparoscopic versus open surgery for left flexure colon cancer: A propensity score matched analysis from an international cohort.

AIM: Surgical treatment of splenic flexure cancer (SFC) still presents some debated issues, including the role of laparoscopic surgery. The literature is based on small single-centre series, while randomized controlled studies comparing open and laparoscopic treatment for colon cancer exclude SFC. This study aimed to determine the role of laparoscopic surgery in the treatment of SFC, comparing short- and long-term outcomes with open surgery. METHOD: This was an international multicentre retrospective cohort study that analysed patients from 10 tertiary referral centres. From a cohort of 641 cases, 484 patients with Stage I-III SFC submitted to elective surgery with curative intent were selected. After 1:1 propensity score matching, 130 patients in the laparoscopic group (LapGroup) were compared with 130 patients in the open surgery group (OpenGroup). RESULTS: After propensity score matching, the two groups were comparable for demographic and clinical parameters. OpenGroup presented a higher incidence of overall (P = 0.02) and surgery-related complications (P = 0.05) but a similar rate of severe complications (P = 0.75). Length of stay was notably shorter in the LapGroup (P = 0.001). Overall (P = 0.793) as well as cancer-specific survival (P = 0.63) did not differ between the two groups. CONCLUSIONS: Elective laparoscopic surgery for Stage I-III SFC is feasible and associated with improved short-term postoperative outcomes compared to open surgery. Moreover, laparoscopic surgery appears to provide excellent long-term cancer outcomes.

Multimodal Prehabilitation During Neoadjuvant Therapy Prior to Esophagogastric Cancer Resection: Effect on Cardiopulmonary Exercise Test Performance, Muscle Mass and Quality of Life-A Pilot Randomized Clinical Trial.

BACKGROUND: Neoadjuvant therapy reduces fitness, muscle mass, and quality of life (QOL). For patients undergoing chemotherapy and surgery for esophagogastric cancer, maintenance of fitness is paramount. This study investigated the effect of exercise and psychological prehabilitation on anaerobic threshold (AT) at cardiopulmonary exercise testing (CPET). Secondary endpoints included peak oxygen uptake (peak VO2), skeletal muscle mass, QOL, and neoadjuvant therapy completion. METHODS: This parallel-arm randomized controlled trial assigned patients with locally advanced esophagogastric cancer to receive prehabilitation or usual care. The 15-week program comprised twice-weekly supervised exercises, thrice-weekly home exercises, and psychological coaching. CPET was performed at baseline, 2 weeks after neoadjuvant therapy, and 1 week preoperatively. Skeletal muscle cross-sectional area at L3 was analyzed on staging and restaging computed tomography. QOL questionnaires were completed at baseline, mid-neoadjuvant therapy, at restaging laparoscopy, and postoperatively at 2 weeks, 6 weeks and 6 months. RESULTS: Fifty-four participants were randomized (prehabilitation group, n = 26; control group, n = 28). No difference in AT between groups was observed post-neoadjuvant therapy. Prehabilitation resulted in an attenuated peak VO2 decline {-0.4 [95% confidence interval (CI) -0.8 to 0.1] vs. -2.5 [95% CI -2.8 to -2.2] mL/kg/min; p = 0.022}, less muscle loss [-11.6 (95% CI -14.2 to -9.0) vs. -15.6 (95% CI -18.7 to -15.4) cm2/m2; p = 0.049], and improved QOL. More prehabilitation patients completed neoadjuvant therapy at full dose [prehabilitation group, 18 (75%) vs. control group, 13 (46%); p = 0.036]. No adverse events were reported. CONCLUSIONS: This study has demonstrated some retention of cardiopulmonary fitness (peak VO2), muscle, and QOL in prehabilitation subjects. Further large-scale trials will help determine whether these promising findings translate into improved clinical and oncological outcomes. Trial Registration ClinicalTrials.gov NCT02950324.

Diagnostic accuracy of point of care faecal immunochemical testing using a portable high-speed quantitative analyser for diagnosis in 2-week wait patients.

AIM: Laboratory-based faecal immunochemical testing (FIT) is the gold standard for detecting the presence of blood in the stool. The aim was to perform a diagnostic accuracy study to confirm if a point of care (POC) analyser for FIT could be safely used as an adjunct in the triage and management of 2-week wait (TWW) colorectal patients. METHODS: The Point of Care Faecal Immunochemical Testing (POC FIT) prospective observational cohort study was designed for TWW patients at a regional referral centre. Between July 2019 and March 2020, patients were invited to perform and bring a FIT sample to clinic. FIT was completed within the clinic appointment using a POC quantitative analyser that has a 2-min processing time (QuikRead go®). Patients and clinicians were blinded to results within the clinic appointment. The results were compared with subsequent diagnostic outcomes. Faecal haemoglobin of <10 µg haemoglobin/g of faeces was considered a negative result. Sensitivities for colorectal cancer (CRC) and combined serious bowel disease (SBD) were calculated using this pre-determined cut-off. RESULTS: A total of 553 patients were included for analytical comparison with diagnostic outcomes. There were 14 (2.5%) patients with CRC and 52 (9.4%) with SBD. The sensitivities for CRC and SBD were 92.9% (95% CI 68.5%-98.7%) and 76.9% (95% CI 63.9%-86.3%) respectively. 379 (68.5%) patients had a negative FIT result (negative predictive value for CRC was 99.7%). CONCLUSIONS: This POC FIT device is a useful adjunct to better manage TWW patients. The high observed sensitivity for CRC offers opportunities, within a single consultation, for improved triage and rationalization of investigation for those with bowel symptoms.

Protocolo ERAS® en cirugía colorrectal / ERAS® in Colorectal Surgery

RESUMEN El protocolo de recuperación optimizada Enhanced Recovery After Surgery (ERAS®) en cirugía colo rrectal promueve un retorno más rápido a la función orgánica siguiendo la evidencia de las últimas investigaciones dirigidas a disminuir el estrés quirúrgico. La vía perioperatoria recomendada está per feccionada, es dinámica y se ajusta a las últimas investigaciones basadas en la evidencia para mejorar todos los aspectos de la atención quirúrgica del paciente. En este artículo describiremos los cuatro aspectos de un paciente a quien se le realizará una cirugía colorrectal: preadmisión, preoperatorio, in traoperatorio y posoperatorio El tema recurrente es disminuir el estrés fisiológico general relacionado con la cirugía; para ello, las intervenciones se superponen a lo largo del recorrido que hace el paciente. Utilizando un enfoque multidisciplinario, la adherencia al protocolo ERAS® en cirugía colorrectal cum pliendo con el 70% o más de las intervenciones de ERAS® ha demostrado una reducción del riesgo de muerte relacionada con el cáncer del 42% a los 5 años. Las intervenciones óptimas no solo se determi nan mediante la publicación de investigaciones de alta calidad, sino que la colaboración internacional periódica permite compartir experiencias e investigaciones y estandarizar los cuidados.

ABSTRACT Enhanced Recovery After Surgery (ERAS®) in colorectal surgery is a protocol that promotes quicker return to function. It follows the latest evidence-based research to promote stress reduction related to surgery. The recommended perioperative pathway is fine-tuned, dynamic and in line with the latest evidence-based research to enhance all aspects of the patient's surgical care. We describe the four aspects for a patient undergoing colorectal surgery - pre-admission, pre-operative, intra-operative and post-operative. The running theme is to reduce overall physiological stress related to surgery and interventions overlap throughout the patient's pathway. Using a multidisciplinary approach, adheren ce to ERAS® in colorectal surgery with ≥70 % compliance to the ERAS interventions has shown a risk reduction of 5-year cancer-related death by 42%. The optimum interventions are not only determined through the publication of high-quality research, but regular international collaboration enables expe rience and research to be shared and care standardized.

Adoption of faecal immunochemical testing for 2-week-wait colorectal patients during the COVID-19 pandemic: an observational cohort study reporting a new service at a regional centre.

AIM: The COVID-19 pandemic has resulted in the near-complete loss of routine endoscopy services. We describe a major reorganization of service at a regional referral centre (Royal Surrey NHS Foundation Trust) to manage the crisis. Faecal immunochemical testing (FIT) was implemented for triage to make optimum use of limited diagnostic resources. Consultations were switched from face-to-face to telephone. Our aim was to evaluate the impact FIT had on resource allocation and patient diagnoses in the first 3 months of use. METHOD: All colorectal 2-week-wait patient referrals were posted a pack requesting FIT and notification of telephone consultation. A prepaid envelope was included for return of the samples. At consultation, FIT was incorporated with the presenting symptoms to guide the choice of investigation and triage urgency. FIT ≥10 µg/g was interpreted as positive. Outcome data were collected prospectively and compared with retrospective audit data from prepandemic levels across 3 months. RESULTS: From 26 March 2020 to 2 July 381 patients were referred who were invited to provide FIT samples and underwent telephone consultations. Three hundred and fifty eight FIT samples were returned (94%). Onward referral for colonoscopy reduced from 62% to 34% (P < 0.001). There were 14 colorectal cancers (CRC) (3.7%) diagnosed, which was not statistically different from the prepandemic level of 3.9% (P = 0.995). Twelve of the 14 patients with a CRC diagnosis had provided samples; all 12 had FIT ≥10 µg/g and were offered fast-track investigations. CONCLUSIONS: The incorporation of FIT optimized the allocation of limited resources to triage those who required urgent colonic investigation for detecting CRC.

The Role of Circular RNAs in Pancreatic Ductal Adenocarcinoma and Biliary-Tract Cancers.

Pancreatic Ductal Adenocarcinoma (PDAC) and biliary-tract cancers (BTC) often present at a late stage, and consequently patients have poor survival-outcomes. Circular RNAs (circRNAs) are non-coding RNA molecules whose role in tumourigenesis has recently been realised. They are stable, conserved and abundant, with tissue-specific expression profiles. Therefore, significant interest has arisen in their use as potential biomarkers for PDAC and BTC. High-throughput methods and more advanced bioinformatic techniques have enabled better profiling and progressed our understanding of how circRNAs may function in the competing endogenous RNA (ceRNA) network to influence the transcriptome in these cancers. Therefore, the aim of this systematic review was to describe the roles of circRNAs in PDAC and BTC, their potential as biomarkers, and their function in the wider ceRNA network in regulating microRNAs and the transcriptome. Medline, Embase, Scopus and PubMed were systematically reviewed to identify all the studies addressing circRNAs in PDAC and BTC. A total of 32 articles were included: 22 considering PDAC, 7 for Cholangiocarcinoma (CCA) and 3 for Gallbladder Cancer (GBC). There were no studies investigating Ampullary Cancer. Dysregulated circRNA expression was associated with features of malignancy in vitro, in vivo, and ex vivo. Overall, there have been very few PDAC and BTC tissues profiled for circRNA signatures. Therefore, whilst the current studies have demonstrated some of their functions in these cancers, further work is required to elucidate their potential role as cancer biomarkers in tissue, biofluids and biopsies.