Molecular biology of cholangiocarcinoma and its implications for targeted therapy in patient management

Cholangiocarcinoma (CCA) remains a devastating malignancy and a significant challenge to treat. The majority of CCA patients are diagnosed at an advanced stage, making the disease incurable in most cases. The advent of high-throughput genetic sequencing has significantly improved our understanding of the molecular biology underpinning cancer. The identification of 'druggable' genetic aberrations and the development of novel targeted therapies against them is opening up new treatment strategies. Currently, 3 targeted therapies are approved for use in CCA; Ivosidenib in patients with IDH1 mutations and Infigratinib/Pemigatinib in those with FGFR2 fusions. As our understanding of the biology underpinning CCA continues to improve it is highly likely that additional targeted therapies will become available in the near future. This is important, as it is thought up to 40 % of CCA patients harbour a potentially actionable mutation. In this review we provide an overview of the molecular pathogenesis of CCA and highlight currently available and potential future targeted treatments.

Current and future genomic applications for surgeons

Genomics is a crucial part of managing surgical disease. This review focuses on some of the genomic advances that are available now and looks to the future of their application in surgical practice. Whole-genome sequencing enables unbiased coverage across the entire human genome of approximately three billion base pairs. Newer technologies, such as those that permit long-read sequence analysis, provide additional information in longer phased fragment and base pair epigenomic (methylomic) data. Whole-genome sequencing is currently available in England for cancers in children, teenagers and young adults, central nervous system tumours, sarcoma and haematological malignancies. Circulating tumour DNA (ctDNA), immunotherapy and pharmacogenomics have emerged as groundbreaking approaches in the field of cancer treatment. These are now revolutionising the way oncologists and surgeons approach curative cancer surgery. Cancer vaccines offer an innovative approach to reducing recurrence after surgery by priming the immune system to trigger an immune response. The Cancer Vaccine Launch Pad project facilitates cancer vaccine studies in England. The BNT122-01 trial is recruiting patients with ctDNA-positive high-risk colorectal cancer after surgery to assess the impact of cancer vaccines. The evolving landscape of cancer treatment demands a dynamic and integrated approach from the surgical multidisciplinary team. Immunotherapy, ctDNA, pharmacogenomics, vaccines, mainstreaming and whole-genome sequencing are just some of the innovations that have the potential to redefine the standards of care. The continued exploration of these innovative diagnostics and therapies, the genomic pathway evolution and their application in diverse cancer types highlights the transformative impact of precision medicine in surgery.

Postoperative surveillance after surgery for colorectal liver metastasis: a cross-sectional study

INTRODUCTION

Colorectal liver metastases (CRLM) are associated with a high recurrence rate after surgery. There is paucity of high-quality evidence regarding the nature and overall benefit of surveillance after hepatectomy for CRLM. As part of a broader programme of research, this study aimed to assess current strategies for surveillance after liver resection for CRLM and outline surgeons' opinions regarding the benefit of postoperative surveillance.

METHODS

An online survey was sent to clinicians performing surgery for CRLM at tertiary hepatobiliary centres in the UK.

RESULTS

There were responses from a total of 23 centres (88% response rate); 15/23 centres used standardised surveillance protocols for all patients. Most centres followed patients up at six months, but there is variation in postoperative surveillance at 3, 9, 18 and beyond 60 months. Patient comorbidities, indeterminate findings on imaging, margin status and assessment of recurrence risk were identified as the major factors influencing personalised surveillance strategies. There was clear clinician equipoise regarding the costs and benefits of surveillance.

CONCLUSION

There is heterogeneity in postoperative follow-up for CRLM in the UK. High-quality prospective studies and randomised trials are necessary to elucidate the value of postoperative surveillance and identify optimal follow-up strategies.

Synthetic glycolipid-based TLR4 antagonists negatively regulate TRIF-dependent TLR4 signalling in human macrophages

TLRs, including TLR4, play a crucial role in inflammatory-based diseases, and TLR4 has been identified as a therapeutic target for pharmacological intervention. In previous studies, we investigated the potential of FP7, a novel synthetic glycolipid active as a TLR4 antagonist, to inhibit haematopoietic and non-haematopoietic MyD88-dependent TLR4 pro-inflammatory signalling. The main aim of this study was to investigate the action of FP7 and its derivative FP12 on MyD88-independent TLR4 signalling in THP-1 derived macrophages. Western blotting, Ab array and ELISA approaches were used to explore the effect of FP7 and FP12 on TRIF-dependent TLR4 functional activity in response to LPS and other endogenous TLR4 ligands in THP-1 macrophages. A different kinetic in the inhibition of endotoxin-driven TBK1, IRF3 and STAT1 phosphorylation was observed using different LPS chemotypes. Following activation of TLR4 by LPS, data revealed that FP7 and FP12 inhibited TBK1, IRF3 and STAT1 phosphorylation which was associated with down-regulation IFN-β and IP-10. Specific blockage of the IFN type one receptor showed that these novel molecules inhibited TRIF-dependent TLR4 signalling via IFN-β pathways. These results add novel information on the mechanism of action of monosaccharide FP derivatives. The inhibition of the TRIF-dependent pathway in human macrophages suggests potential therapeutic uses for these novel TLR4 antagonists in pharmacological interventions on inflammatory diseases.

The way healthcare is funded is wrong: it should be linked to deaths as well as age, gender and social deprivation

BACKGROUND

most spending on health occurs in the last few months of life. This study explored the number of deaths in England and their relationship to healthcare funding.

METHODS

post hoc analysis Results: the number of deaths range from 3.3 to 15.1/1000/year, and the number of deaths per general practitioner from 5.2 to 27.3/year. Hospital deaths range from 12 to 52/1000 admissions. The correlation between the allocation index used for funding and deaths is not perfect and suggests that some regions may get up to17% less and others 14% more funding than is equitable.

CONCLUSION

there is considerable variation in the prevalence of death throughout England. If healthcare funding considered the local number of deaths it would be more equitable.

Exome sequencing of synchronously resected primary colorectal tumours and colorectal liver metastases to inform oncosurgical management

BACKGROUND

Next generation sequencing technology has facilitated mapping of the colorectal cancer genotype and furthered our understanding of metastogenesis. The aim of this study was to investigate for conserved and different mutations in the exomes of synchronously resected primary colorectal tumour and liver metastases. This information could potentially be utilised to guide the treatment of advanced disease with the help of biological information from the primary tumour.

METHODS

We performed exome sequencing of synchronously resected primary colorectal cancer and colorectal liver metastases as well as normal colonic mucosa and liver parenchyma, from four patients who had received neo-adjuvant chemotherapy, at a depth of 50X using the Ion Proton platform. Raw data was mapped to the reference genome prior to variant calling, annotation and downstream analysis.

RESULTS

Exome sequencing identified 585 non-synonymous missense single nucleotide variants (SNVs), of which 215 (36.8%) were unique to the primary tumour, 226 (38.6%) unique to the metastasis and 81 (13.8%) present in patient matched pairs. SNVs identified in the ErbB pathway appear to be concordant between primary and metastatic tumours.

CONCLUSION

Only 13.8% of the metastatic exome can be predicted by the genotype of the primary tumour. We have demonstrated concordance of a number of SNVs in the ErbB pathway, which may inform selection of therapeutic agents in advanced colorectal cancer.

Precision surgery for colorectal liver metastases: Opportunities and challenges of omics-based decision making

Precision surgery involves improving patient selection to ensure that surgical intervention that is proven to benefit on a population level is the optimal treatment for each individual patient. For patients with colorectal liver metastases (CRLM), existing prognostic scoring systems rely on well-recognised histopathological features such as size and number of lesions. Advances in preoperative imaging algorithms mean that increasingly low volume disease can be detected, improving assessment of these factors. In addition, novel imaging modalities mean that underlying tumour biology and metabolic behaviour during therapy can be assessed. Molecular analysis of tumours can provide crucial prognostic information, with the critical role of RAS/RAF mutations in prognosis well recognised. The optimal source of tissue for this level of analysis is debated, with good concordance between primary and metastatic lesions for some recognised prognostic factors but marked discrepancies for a variety of other relevant mutations. As well as mutational heterogeneity between primary and metastatic lesions, heterogeneity within tumours and dynamic changes in tumour biology over time present a significant challenge in assessing tumour for prognostic biomarkers. Circulating tumour cells offer one potential method of longitudinal tumour analysis, but are limited by current technologies. This review article summarises some of the key advances in prognostication for patients with resectable colorectal liver metastases, as well as highlighting the potential limitations of such an approach.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

PARAGON II - A single arm multicentre phase II study of neoadjuvant therapy using irinotecan bead in patients with resectable liver metastases from colorectal cancer

PURPOSE

Perioperative chemotherapy confers a 3-year progression free survival advantage following resection of colorectal liver metastases (CRLM), but is associated with significant toxicity. Chemoembolisation using drug eluting PVA microspheres loaded with irinotecan (DEBIRI) allows sustained delivery of drug directly to tumour, maximising response whilst minimising systemic exposure. This phase II single arm study examined the safety and feasibility of DEBIRI before resection of CRLM.

METHODS

Patients with resectable CRLM received lobar DEBIRI 1 month prior to surgery, with a radiological endpoint of near stasis. The trial had a primary end-point of tumour resectability (R0 resection). Secondary end-points included safety, pathologic tumour response and overall survival.

RESULTS

40 patients received DEBIRI, with a median dose of 103 mg irinotecan (range 64-175 mg). Morbidity was low (2.5%, CTCAE grade 2) with no evidence of systemic chemotoxicity. All patients proceeded to surgery, with 38 undergoing resection (95%, R0 resection rate 74%). 30-day post-operative mortality was 5% (n = 2), with neither death TACE related. 66 lesions were resected, with histologic major or complete pathologic response seen in 77.3% of targeted lesions. At median follow up of 40.6 months, 12 patients (34.3%) had died of recurrent disease with a median overall survival of 50.9 months. Nominal 1, 3 and 5-year OS was 93, 78 & 49% respectively.

CONCLUSIONS

Resection after neoadjuvant DEBIRI for CRLM is feasible and safe. Single treatment with DEBIRI resulted in tumour pathologic response and median overall survival comparable to that seen after systemic neoadjuvant chemotherapy. Registered at clinicaltrials.gov (NCT00844233).

Randomized clinical trial of prehabilitation before planned liver resection

BACKGROUND

Patients with low fitness as assessed by cardiopulmonary exercise testing (CPET) have higher mortality and morbidity after surgery. Preoperative exercise intervention, or prehabilitation, has been suggested as a method to improve CPET values and outcomes. This trial sought to assess the capacity of a 4-week supervised exercise programme to improve fitness before liver resection for colorectal liver metastasis.

METHODS

This was a randomized clinical trial assessing the effect of a 4-week (12 sessions) high-intensity cycle, interval training programme in patients undergoing elective liver resection for colorectal liver metastases. The primary endpoint was oxygen uptake at the anaerobic threshold. Secondary endpoints included other CPET values and preoperative quality of life (QoL) assessed using the SF-36®.

RESULTS

Thirty-eight patients were randomized (20 to prehabilitation, 18 to standard care), and 35 (25 men and 10 women) completed both preoperative assessments and were analysed. The median age was 62 (i.q.r. 54-69) years, and there were no differences in baseline characteristics between the two groups. Prehabilitation led to improvements in preoperative oxygen uptake at anaerobic threshold (+1·5 (95 per cent c.i. 0·2 to 2·9) ml per kg per min) and peak exercise (+2·0 (0·0 to 4·0) ml per kg per min). The oxygen pulse (oxygen uptake per heart beat) at the anaerobic threshold improved (+0·9 (0·0 to 1·8) ml/beat), and a higher peak work rate (+13 (4 to 22) W) was achieved. This was associated with improved preoperative QoL, with the overall SF-36® score increasing by 11 (95 per cent c.i. 1 to 21) (P = 0·028) and the overall SF-36® mental health score by 11 (1 to 22) (P = 0·037).

CONCLUSION

A 4-week prehabilitation programme can deliver improvements in CPET scores and QoL before liver resection. This may impact on perioperative outcome.

REGISTRATION NUMBER

NCT01523353 (https://clinicaltrials.gov).

National survey on endoscopy training in the UK

INTRODUCTION

Gastrointestinal (GI) endoscopy is an important skill for both gastroenterologists and general surgeons but concerns have been raised about the provision and delivery of training. This survey aimed to evaluate and compare the delivery of endoscopy training to gastroenterology and surgical trainees in the UK.

METHODS

A nationwide electronic survey was carried out of UK gastroenterology and general surgery trainees.

RESULTS

There were 216 responses (33% gastroenterologists, 67% surgeons). Gastroenterology trainees attended more non-training endoscopy lists (mean: 3.0 vs 1.2) and training lists than surgical trainees (mean: 0.9 vs 0.5). A significantly higher proportion of gastroenterologists had already achieved accreditation in gastroscopy (60.8% vs 28.9%), colonoscopy (66.7% vs 1.4%) and flexible sigmoidoscopy (33.3% vs 3.0%). More gastroenterology trainees aspired to achieve accreditation in gastroscopy (97.2% vs 79.2%), flexible sigmoidoscopy (91.7% vs 70.1%) and colonoscopy (88.8% vs 55.5%) by completion of training. By completion of training, surgeons were less likely than gastroenterologists to have completed the required number of procedures to gain accreditation in gastroscopy (60.3% vs 91.3%), flexible sigmoidoscopy (64.6% vs 68.6%) and colonoscopy (60.3% vs 70.3%).

CONCLUSIONS

This survey highlights marked disparities between surgical and gastroenterology trainees in both aiming for and achieving accreditation in endoscopy. Without changes to the delivery and provision of training as well as clarification of the role of endoscopy training in a surgical training programme, future surgeons will not be able to perform essential endoscopic assessment of patients as part of their management algorithm.

Clinical follow-up does not improve survival after resection of stage I-III colorectal cancer: A cohort study

INTRODUCTION

The benefit of clinical follow-up alongside CT & CEA in detecting recurrent colorectal cancer (CRC) remains unclear. Despite this, clinical review remains part of most surveillance protocols. This study assessed the efficacy of clinical follow-up in addition to CT/CEA in detecting disease recurrence.

METHODS

Patients undergoing surgery for CRC at a single centre between 2009 and 2011 were identified. Follow-up included clinical review, CT and CEA for 5 years. The primary endpoint of the study was method of detection of recurrence. Secondary endpoints included detection of surgically treatable recurrence, compliance with follow-up, disease free survival and overall survival.

RESULTS

118 patients with stage I-III CRC were included. Only 68.9% of scheduled follow-up events were performed (76.6% clinical reviews, 76.2% CT scans and 60.4% CEA tests). At median follow-up of 36 months, 26 patients had developed recurrence (median DFS 45.8 months). 17 patients (14.7%) had died (median OS 49.3 months). Sensitivity and specificity of follow up modality in detecting recurrence were; CT (92.3%, 100%), CEA (57.7%, 100%), clinical review (23.0%, 27.2%). Addition of clinical review did not identify any disease recurrence that was not detected by scheduled CT. Eight patients (30.7%) had surgically treatable recurrence - all were identified by scheduled CT.

CONCLUSION

The addition of CEA testing and clinical review to scheduled CT scanning offered no benefit in the detection of recurrent disease. Clinical review could be removed from follow-up protocols without any reduction in the detection of recurrent cancer.

Evaluation of a novel tissue stabilization gel to facilitate clinical sampling for translational research in surgical trials

Background

The aim was to establish the feasibility of using a tissue stabilization gel (Allprotect™) as an alternative to liquid nitrogen to facilitate collection of clinical samples for translational research.

Methods

Tumour samples from patients undergoing surgery for primary or metastatic colorectal cancer were either snap-frozen in liquid nitrogen or stored in Allprotect™ under a number of different conditions. Sample integrity was compared across different storage conditions by assessing biomolecule stability and function. DNA quality was assessed spectrophotometrically and by KRas genotyping by pyrosequencing. Total RNA retrieval was determined by nanodrop indices/RNA integrity numbers, and quality assessed by reverse transcription–PCR for two representative genes (high-mobility group box 1, HMGB1; carboxylesterase 1, CES1) and two microRNAs (miR122 and let7d). Western blot analysis of HMGB1 and CES1 was used to confirm protein expression, and the metabolic conversion of irinotecan to its active metabolite, SN-38, was used to assess function.

Results

Under short-term storage conditions (up to 1 week) there was no apparent difference in quality between samples stored in Allprotect™ and those snap-frozen in liquid nitrogen. Some RNA degradation became apparent in tissue archived in Allprotect™ after 1 week, and protein degradation after 2 weeks.

Conclusion

In hospitals that do not have access to liquid nitrogen and –80°C freezers, Allprotect™ provides a suitable alternative for the acquisition and stabilization of clinical samples. Storage proved satisfactory for up to 1 week, allowing transfer of samples without the need for specialized facilities. Surgical relevanceAccess to clinical material is a fundamental component of translational research that requires significant infrastructure (research personnel, liquid nitrogen, specialized storage facilities). The aim was to evaluate a new-to-market tissue stabilization gel (Allprotect™), which offers a simple solution to tissue preservation without the need for complex infrastructure.Allprotect™ offers comparable DNA, RNA and protein stabilization to tissue snap-frozen in liquid nitrogen for up to 1 week. Degradation of biomolecules beyond this highlights its role as a short-term tissue preservative.Allprotect™ has the potential to increase surgeon participation in translational research and surgical trials requiring tissue collection.

Unexpected and unexplained increase in death due to neurological disorders in 2012 in England and Wales: is cytomegalovirus implicated?

In early 2012 deaths (all-cause mortality) in England and Wales showed an unexpected and unexplained increase which continued for 18 months before abating. The highest percentage increase in deaths was noted to be for neurological degenerations (mainly dementia, Alzheimer's, Parkinson's). This study seeks to understand why increased deaths should focus on these conditions and if an unrecognized infectious outbreak could be implicated. Cause of death statistics for England and Wales were compared for 2012 versus 2011 as was the diagnosis for first outpatient appointment and inpatient admissions for these conditions. Deaths for dementia, Alzheimer's and Parkinson's showed a 15% increase with associated age specificity. The increase could not be explained by changes in the coding relating to cause of death. The increase coincided with increased GP referral (as first outpatient attendance) and inpatient admission for a range of neurological conditions. These increases were also observed on previous occasions of a similar event where deaths peaked in 2003 and 2008. A cascade of debility leading to immobility and institutionalization along with specific immune impairments appears to render those suffering from neurological degenerations sensitive to infectious outbreaks and more specifically to the particular agent behind these events. These and other studies point to outbreaks of a previously uncharacterized agent with the outbreak peaking in 2003, 2008 and 2012 (and in other years prior to these dates). Cytomegalovirus is a potential candidate and the necessary research to test this hypothesis is outlined.

Hepatic activation of irinotecan predicts tumour response in patients with colorectal liver metastases treated with DEBIRI: exploratory findings from a phase II study

PURPOSE

The response of colorectal liver metastases to the cytotoxic agent irinotecan varies widely. Attempts to correlate tumour metabolism with response have been mixed. This study investigated the hepatic metabolism of irinotecan as a potential predictor of tumour response to irinotecan-eluting beads (DEBIRI).

METHODS

Ten patients with colorectal liver metastases were treated with 200 mg irinotecan (as DEBIRI) as part of the PARAGON II study. Hepatic expression of key metabolising enzymes was measured using mass spectrometry-based proteomics. Serum drug concentrations and hepatic irinotecan metabolism were characterised and correlated with tumour response.

RESULTS

Serum concentrations of irinotecan metabolites did not correlate with hepatic metabolism or pathological response. There was a strong correlation between hepatic CES-2 expression and activation of irinotecan (r (2) = 0.96, p < 0.001). Patients with a UGT1A1*28 6/7 SNP showed no difference in drug metabolism or pathological response. Hepatic CES-2 mediated activation of irinotecan clearly correlated with tumour replacement by fibrosis (r (2) = 0.54, p = 0.01).

CONCLUSION

This study provides the first evidence that hepatic activation of irinotecan predicts tumour response. Delivery of liver-targeted irinotecan to normal liver tissue rather than tumour may be a more rational approach to maximise response.

Routine staging laparoscopy has no place in the management of colorectal liver metastases

AIMS

Staging laparoscopy has been recommended in the management of patients with colorectal liver metastases prior to hepatectomy in order to reduce the incidence and associated morbidity of futile laparotomies. The utility of staging laparoscopy has not been assessed in patients undergoing CT, PET-CT and MRI as standard preoperative staging.

METHODS

All patients undergoing attempted open hepatectomy for colorectal liver metastases between 1/4/2008 and 31/3/2012 were identified from a prospectively maintained research database. All patients who underwent futile laparotomy were identified, with demographics and operative notes subsequently analysed.

RESULTS

A total of 274 patients underwent attempted open hepatectomy during the study period. At laparotomy 12 (4.4%) patients were found to have irresectable disease. There were no unifying demographic factors within the patients undergoing futile laparotomy.

CONCLUSIONS

With modern imaging, the potential yield of staging laparoscopy is low. Staging laparoscopy should not be used routinely, but may have a role in the case of specific clinical concerns.

The history of adoption of hepatic resection for metastatic colorectal cancer: 1984-95

BACKGROUND

Liver resection for metastatic colorectal cancer became established without randomized trials. Proponents of surgical resection point out 5-year survival approaching 50% whilst critics question how much of the apparent effect is due to patient selection.

METHOD

A 2006 systematic review of reported outcomes provided the starting point for citation analysis followed by thematic analysis of the texts of the most cited papers.

RESULTS

54 reports from 1988 to 2002 cited 709 unique publications a total of 1714 times. The 15 most cited papers were explored in detail, and showed clear examples of duplicate reporting and overlapping data sets. Textual analysis revealed proposals for a randomized controlled trial, but this was argued to be unethical by others, and no trial was undertaken.

CONCLUSIONS

This critical review reveals how the case for this surgery was made, and examines the arguments that influenced acceptance and adoption of this surgery.

Effect of specialist decision-making on treatment strategies for colorectal liver metastases

BACKGROUND

One hundred and ten patients were treated with palliative chemotherapy, of whom 53 had liver-only disease and had not been reviewed by a specialist liver surgeon. One scan was excluded as all reviewers felt it to be of insufficient quality to assess. Improved surgical technique and better chemotherapeutic manipulation of metastatic disease has increased the number of patients eligible for potentially curative resection of colorectal liver metastases. The rapid evolution in this field suggests that non-specialist decision-making may lead to inappropriate management. This study aimed to assess the management of colorectal liver metastases by non-liver surgeons.

METHODS

All patients who underwent chemotherapy with palliative intent for metastatic colorectal cancer at a regional oncology centre between 1 January and 31 December 2009 were identified from a prospectively maintained local database. Six resectional liver surgeons blinded to patient management and outcome reviewed pretreatment imaging and assigned each scan a score based on their own management choice. A consensus decision was reached on the appropriateness of palliative chemotherapy.

RESULTS

One hundred and ten patients were treated with palliative chemotherapy, of whom 53 had liver-only disease and had not been reviewed by a specialist liver surgeon. One scan was excluded as all reviewers felt it to be of insufficient quality to assess [corrected]. Tumours in 33 patients (63 per cent) were considered potentially resectable, with a high level of interobserver agreement (κ = 0 · 577). When individual approach to management was considered, interobserver agreement was less marked (κ = 0 · 378).

CONCLUSION

Management of patients with colorectal liver metastases without the involvement of a specialist liver multidisciplinary team can lead to patients being denied potentially curative treatments. Management of these patients must involve a specialist liver surgeon to ensure appropriate management.

Effect of specialist decision-making on treatment strategies for colorectal liver metastases

Background

One hundred and ten patients were treated with palliative chemotherapy, of whom 53 had liver-only disease and had not been reviewed by a specialist liver surgeon. One scan was excluded as all reviewers felt it to be of insufficient quality to assess. Improved surgical technique and better chemotherapeutic manipulation of metastatic disease has increased the number of patients eligible for potentially curative resection of colorectal liver metastases. The rapid evolution in this field suggests that non-specialist decision-making may lead to inappropriate management. This study aimed to assess the management of colorectal liver metastases by non-liver surgeons.

Methods

All patients who underwent chemotherapy with palliative intent for metastatic colorectal cancer at a regional oncology centre between 1 January and 31 December 2009 were identified from a prospectively maintained local database. Six resectional liver surgeons blinded to patient management and outcome reviewed pretreatment imaging and assigned each scan a score based on their own management choice. A consensus decision was reached on the appropriateness of palliative chemotherapy.

Results

Tumours in 33 patients (63 per cent) were considered potentially resectable, with a high level of interobserver agreement (κ = 0·577). When individual approach to management was considered, interobserver agreement was less marked (κ = 0·378).

Conclusion

Management of patients with colorectal liver metastases without the involvement of a specialist liver multidisciplinary team can lead to patients being denied potentially curative treatments. Management of these patients must involve a specialist liver surgeon to ensure appropriate management.

Systematic review and meta-analysis of follow-up after hepatectomy for colorectal liver metastases2

Background

The evidence surrounding optimal follow-up after liver resection for colorectal metastases remains unclear. A significant proportion of recurrences occur in the early postoperative period, and some groups advocate more intensive review at this time.

Methods

A systematic review of literature published between January 2003 and May 2010 was performed. Studies that described potentially curative primary resection of colorectal liver metastases that involved a defined follow-up protocol and long-term survival data were included. For meta-analysis, studies were grouped into intensive (more frequent review in the first 5 years after resection) and uniform (same throughout) follow-up.

Results

Thirty-five studies were identified that met the inclusion criteria, involving 7330 patients. Only five specifically addressed follow-up. Patients undergoing intensive early follow-up had a median survival of 39·8 (95 per cent confidence interval 34·3 to 45·3) months with a 5-year overall survival rate of 41·9 (34·4 to 49·4) per cent. Patients undergoing routine follow-up had a median survival of 40·2 (33·4 to 47·0) months, with a 5-year overall survival rate of 38·4 (32·6 to 44·3) months.

Conclusion

Evidence regarding follow-up after liver resection is poor. Meta-analysis failed to identify a survival advantage for intensive early follow-up.

Intermittent small bowel obstruction caused by Meckel's enterolith

A 56-year-old man presented with small bowel obstruction after a 6-week history of intermittent resolving subacute small bowel obstruction. After investigations, he underwent laparotomy. A mobile, narrow-necked Meckel's diverticulum packed with enteroliths pressing against proximal small bowel was discovered. A small bowel resection was performed.

The effect of electromagnetic interference from mobile communication on the performance of intensive care ventilators

Electromagnetic interference produced by wireless communication can affect medical devices and hospital policies exist to address this risk. During the transfer of ventilated patients, these policies may be compromised by essential communication between base and receiving hospitals. Local wireless networks (e.g. Bluetooth) may reduce the 'spaghetti syndrome' of wires and cables seen on intensive care units, but also generate electromagnetic interference. The aim of this study was to investigate these effects on displayed and actual ventilator performance.

METHODS

Five ventilators were tested: Drager Oxylog 2000, BREAS LTV-1000, Respironics BiPAP VISION, Puritan Bennett 7200 and 840. Electromagnetic interference was generated by three devices: Simoco 8020 radio handset, Nokia 7210 and Nokia 6230 mobile phone, Nokia 6230 communicating via Bluetooth with a Palm Tungsten T Personal Digital Assistant. We followed the American National Standard Recommended Practice for On-Site, Ad Hoc Testing (ANSI C63) for electromagnetic interference. We used a ventilator tester, to simulate healthy adult lungs and measure ventilator performance. The communication device under test was moved in towards each ventilator from a distance of 1 m in six axes. Alarms or error codes on the ventilator were recorded, as was ventilator performance.

RESULTS

All ventilators tested, except for the Respironics VISION, showed a display error when subjected to electromagnetic interference from the Nokia phones and Simoco radio. Ventilator performance was only affected by the radio which caused the Puritan Bennett 840 to stop functioning completely. The transfer ventilators' performance were not affected by radio or mobile phone, although the mobile phone did trigger a low-power alarm. Effects on intensive care ventilators included display reset, with the ventilator restoring normal display function within 2 s, and low-power/low-pressure alarms. Bluetooth transmission had no effect on the function of all the ventilators tested.

CONCLUSION

In a clinical setting, high-power-output devices such as a two-way radio may cause significant interference in ventilator function. Medium-power-output devices such as mobile phones may cause minor alarm triggers. Low-power-output devices such as Bluetooth appear to cause no interference with ventilator function.

Troponin I, laboratory issues, and clinical outcomes in a district general hospital: crossover study with "traditional" markers of myocardial infarction in a total of 1990 patients

AIMS

Review of the clinical outcomes and practical issues of replacing traditional cardiac enzymes with troponin I (cTnI) in a district general hospital.

METHODS

Crossover study of three sequential three month stages during which serial cardiac enzymes were replaced with a single cTnI measurement available at three set times within 24 hours for the duration of the second three month stage. The study was carried out in a 630 bed district general hospital with 1990 admissions of suspected cardiac ischaemia over the study period as a whole. Account was taken of seasonal factors.

RESULTS

The introduction of troponin was associated with 8.5% more patients with non-ischaemic heart disease (IHD) being discharged on the day after admission, saving approximately 107 bed days each year. Approximately 50% more patients were diagnosed with myocardial infarction during the cTnI stage. There was no increase in readmission within one month or early death with cTnI. Approximately 3% false positive and 1.5% false negative cTnI results were recorded. All false positive cTnI results were coding errors or attributable to known assay interference effects. All false negatives were potentially explained by sample timing factors. The lack of standardisation in troponin assay services impacts clinically.

CONCLUSION

Younger patients without IHD were discharged earlier during the cTnI stage in apparent safety. Blood sample timing needs to be verified when cTnI is used as an adjunct to early discharge. There were no unexplained false positives or negatives. Standardisation related issues arose.

Two-stage hypospadias repair: audit in a district general hospital

The number of techniques for hypospadias repair is testament to the challenges associated with this condition. In 1994, the senior author undertook an audit of his repairs using the van der Meulen [Plast. Reconstr. Surg. 59 (1977) 20615] technique and determined that the revision rate of 11% was unsatisfactory and the cosmetic result sub-optimal. He, therefore, retrained and began in 1995, using the two-stage technique popularised by Bracka [Br. J. Plast. Surg. 48 (1995) 345]. We undertook an audit of all corrections performed in the period from September 1995 to March 2002. The computer database in the main theatre suite was used to identify all patients on whom such a repair had been undertaken and those notes retrieved. Data was collected on a number of variables including age at operations, complications such as urinary tract infection and fistulae, and total number of corrective operations. One hundred and nineteen patients were identified, of which seven had no records available. Of the remaining 112, 81 were primary repairs, in whom the complication rate was 2.5% for stage I (graft loss) and 9.8% for stage II (fistula rate 7.4%, stenosis 1.2%, baggy urethra requiring reconstruction 1.2%). The remaining 31 patients were those with unsatisfactory single-stage repairs and in this group, graft loss was seen in three cases (10%). The fistula rate was 4/31 (12.9%) and the stenosis rate 2/31 (6.5%). These results compare favourably with a number of published series from surgeons who have super-specialised in this field. We conclude that the two-stage repair is a useful and reliable technique in the hands of a Plastic Surgeon who has a broader interest.

Expression, purification and secondary structure analysis of Saccharomyces cerevisiae vacuolar membrane H+-ATPase subunit F (Vma7p)

The vacuolar H+-ATPase is an acid pump found in virtually all eukaryotic cells. It shares a common macromolecular organization with the F1F0-ATPase, and some V-ATPase subunits are structural and functional homologues of F-ATPase components. However, the vacuolar complex contains several subunits which do not resemble F-ATPase subunits at the sequence level, and which currently have no specific function assigned. One example is subunit F, the Vma7p polypeptide of Saccharomyces cerevisiae. A recombinant form of Vma7p was expressed in Escherichia coli and purified to homogeneity. Mass spectroscopy confirmed a mass of 13460 Da for Vma7p, and dynamic light scattering showed that the polypeptide was globular and monodisperse even at high concentrations. Analysis of secondary structure by circular dichroism and FTIR showed that Vma7p comprises 30% alpha-helix and 32-42% beta-sheet. The protein fold recognition programme 'Threader 2' produced highly significant matches between Vma7p and five alpha-beta sandwich folds. Relative proportions of secondary structure elements within these folds were broadly consistent with the spectroscopic data. Although Vma7p does not share sequence similarity with the F-ATPase epsilon subunit, the analysis suggests that the polypeptides not only have similar masses and assemble into homologous core complexes, but also share similar secondary structures. It is possible that the two polypeptides are homologous and perform similar functions within their respective ATPases. The production of high yields of homogeneous, folded, monodisperse protein will facilitate high resolution crystallography and NMR spectroscopy studies.

The safety of topical anaesthetic and analgesic agents in a gel when used to provide pain relief at split skin donor sites

Post operative pain from split skin donor sites is a recognised problem. This study was carried out to assess the safety of a 'depot' preparation of bupivacaine and ketoprofen when applied to denuded dermis of a split donor site. Two groups of six patients each received either bupivacaine gel (2.5 mg/ml) or ketoprofen gel (1.6 mg/ml). One patient from each group was excluded as protocol was not followed. The mean surface area for bupivacaine was 106 cm2 (range 64-160) and the mean for ketoprofen was 130 cm2 (range 64-180). Blood samples were obtained before application and at 10, 20, 30, 60, 120, 240 and 480 min after application. Serum levels were assayed using Gas Liquid Chromatography and High Pressure Liquid Chromatography. Bupivacaine levels peaked at 120 min, mean level obtained was 0.07 microgram/ml (range 0.03-0.1). Ketoprofen levels also peaked at 120 min and the mean level obtained was 0.20 microgram/ml (range 0.12-0.27). The reported toxic serum level for bupivacaine was 4 micrograms/ml and for ketoprofen is 1128 micrograms/ml. In conclusion, these preparations, when applied to denuded dermis of a split skin donor site, are unlikely to result in toxic levels.

The revolutionary dual cyclone vacuum cleaner--a new cause of digital friction burns in children

Household domestic appliances are often sources of potential hazard for young children. This case report illustrates this with reference to a revolutionary dual cyclone vacuum cleaner causing a full thickness burn in a young child.

Comparison of the fixed combination of enalapril/diltiazem ER and their monotherapies in stage 1 to 3 essential hypertension

The safety and efficacy of two fixed dose combinations of enalapril and diltiazem extended release formation (ER) (E/D) were compared with their monotherapies and placebo in patients with stage 1 to 3 hypertension. The trial design was a multicenter, randomized, double blind, placebo controlled, parallel group, 12 week treatment phase, followed by a 36 week, open label phase. A total of 891 patients with sitting diastolic blood pressure (SiDBP) between 95 and 115 mm Hg were randomly assigned to enalapril 5 mg, diltiazem ER 120 mg, diltiazem ER 180 mg, enalapril 5 mg/diltiazem ER 120 mg (E5/D120), enalapril 5 mg/ diltiazem ER 180 mg (E5/D180), or placebo. In the open label phase, 562 patients received the fixed combination, titrated as needed to control SiDBP < 90 mm Hg. Efficacy was determined with trough (24 +/- 2 h postdose) sitting blood pressure measurements at week 12 and at the end of the open label part of the study. Safety was evaluated based on patient symptoms, clinical laboratories, and electrocardiograms (ECG). E5/D120 and E5/D180 significantly reduced trough SiDBP (-7.6 and -8.3 mm Hg, respectively; P < .05) versus their monotherapies. E5/D120 and E5/D180 significantly reduced trough sitting systolic blood pressure (-7.9 and -9.0, respectively; P < .05) versus both diltiazem ER monotherapies. All active treatments significantly decreased SiDBP and SiSBP versus placebo. E/D effectively lowered SiDBP and SiSBP during the open label extension. No significant difference was seen among treatment groups for the overall incidence of adverse events. The most common drug related adverse events were headache, edema/swelling, dizziness, asthenia/fatigue, cough, rash, and impotence. The event frequency for the combinations were similar to those seen with the monotherapies. Fixed combinations of E/D were generally well tolerated, with an increased blood pressure lowering effect as compared with the individual components in patients with stage I to III hypertension.

The spatial dependence of spin-echo signals

The signals in NMR spin echoes which are refocused by 90 degrees pulses are spatially modulated. The spatial modulation is not normally observed in images or profiles obtained using Hahn or stimulated echoes, but may cause errors if the sample structure varies on the distance scale of the modulation. Localized spectra measured using stimulated echoes will also show errors under these conditions. Simple Fourier-transform arguments show that conditions which allow the modulation to become visible in an image or profile have the effect of introducing a second echo into the time-domain acquisition window. Phase cycling may be used to remove the spatial dependence of the signals.

Control of end-tidal carbon dioxide during IPPV. Variable functional apparatus deadspace

We have described a method for control of end-tidal carbon dioxide tension during intermittent positive pressure ventilation in a model lung and in 19 adults during general anaesthesia supplemented by central or peripheral neural blockade. The inspiratory and expiratory limbs of an open or a circle anaesthesia system were interconnected and ventilated simultaneously in a variable manner during inspiration. The flow of mixed-expired gas, normally one-way, became to-and-fro (variable functional apparatus deadspace, or "virtual' deadspace). At minute volume ventilation > or = 100 ml.kg-1.min-1 (patients), the value of end-tidal carbon dioxide tension was varied reproducibly within the range 4.1-6.5 (SD 0.1)kPa independently of fresh gas flow or other prescribed patterns of ventilation. At a steady state, stable nominated values of end-tidal carbon dioxide tension within the range were attained. By how much any given intra-operative value of end-tidal carbon dioxide tension may be said to affect peri-operative outcome is debatable, but during surgery any change in a nominated value may usefully indicate a change in the steady state.

Heat shock protein studies in type 1 and type 2 diabetes and human islet cell culture

Heat shock proteins (HSP) play an important role in auto-immunity and infection. Glutamic acid decarboxylase (GAD) the prime antigen in Type 1 diabetes has similar amino acid sequences to HSP65. An ELISA was developed using a plant-derived HSP65 antibody. HSP65 antibody was present in the serum of all normal subjects (median 1.64 AU, IQ range 1.49-1.74). Lower levels were found in established Type 1 diabetes (1.41 AU, 1.32-1.61, p < 0.001) and Type 2 diabetes (1.45 AU, 1.35-1.59, p < 0.006). In Type 1 HSP antibody levels fell with age (p = 0.007) and with duration (p = 0.008) and women with Type 1 had lower levels than men (p = 0.009). Human islet cell culture subjected to heat shock revealed an approximate four fold increase in heat shock protein antigen in the surrounding medium. The release of HSP antigen from stressed islet cells together with the finding of HSP antibody in the serum of all subjects suggest that HSP65 should not be completely discarded as having a possible role in the development of Type 1 diabetes. Low levels of HSP antibody in patients with established diabetes is probably a manifestation of impaired immunity induced by the diabetic state.

A plastic container for algal growth potential tests

The substitution of a six ounce plastic cup with snap-cap lid as a growth vessel for a standard algal growth potential test 125 ml glass Erlenmeyer flask has been evaluated. Included are a discussion of desired growth vessel characteristics and the relationship of seven day plastic cup algal growth to maximum (twelve to fourteen day) flask.

Voltage fields surrounding needles used in regional anaesthesia

Using a bench model, we have studied the voltage fields surrounding both insulated and uninsulated needles used in regional anaesthesia. The findings were compared with earlier computer predictions which suggested that the fields would be markedly different for the two types of needle. The results confirm that the fields differ markedly and suggest that the use of insulated needles may not necessarily improve the accuracy of nerve location and that uninsulated needles may be more appropriate.

Variable apparatus deadspace

A variable apparatus deadspace was used to maintain normocapnia during artificial ventilation of the lungs in anaesthetised adults. End-tidal carbon dioxide tension could be varied, if the need arose, within the range 4.0-5.2 kPa in both open and circle breathing systems when a fixed tidal volume of 12 ml.kg-1 and minute volume ventilation of 120 ml.kg-1.min-1 were employed.

Absence status epilepticus resulting from metrizamide and omnipaque myelography

Two cases of absence status are described, one case following metrizamide myelography and the other from omnipaque myelography. Metrizamide has been well known to cause convulsive seizures even in patients without epilepsy. The exact mechanism is not known but appears to be direct neuronal toxic effects possibly due to competitive inhibition of hexokinase activity. The acute confusional state following myelography from water soluble agents is reviewed. In view of the difficulty in clinical diagnosis and the excellent response to anticonvulsant therapy, the possibility of this clinical entity should be specifically excluded by EEG in any person suffering from prolonged confusion following myelography with water soluble agents.

Ethanol and the fluidity of the yeast plasma membrane

Evidence is presented for an exponential increase in yeast plasma membrane fluidity (as measured by passive permeability to acetic acid) with ethanol concentration. The role of adaptation of yeast cells to ethanol can be seen in the existence of a threshold concentration before the onset of an observed fluidizing effect. The physiological state of the yeast cells is also demonstrated to influence the sensitivity of the membrane to fluidization by ethanol. On the basis of these results, the concept that increased fluidity is an adaptive response conferring ethanol tolerance is disputed. An alternative hypothesis, namely that the observed increase in fluidity is the net result of a number of more fundamental changes, is presented to explain the observed effects.

Factors influencing deactivation of yeast cells exposed to ethanol

The lyotropic series discovered in 1888 by Hofmeister describes the effect of solutes on the structure and physical chemistry of the aqueous phase. Chaotropic members of the lyotropic series destructure the aqueous phase while antichaotropic solutes act to enhance the structuredness of the aqueous phase. This alteration of the aqueous phase affects the physical structure or physicochemical state of any other phase exposed to the aqueous phase, such as the plasma membrane of any cell. Solute lyotropy is therefore, via its ability to alter the physicochemical state of the plasma membrane, able to modify the processes of yeast cell deactivation (i.e. the processes leading to loss of ability to replicate and to eventual cell death) in the presence of toxic solutes such as ethanol. In this study the effect of a variety of salts and non-ionic solutes upon cell deactivation in the presence of 16% w/v ethanol is explained in terms of the lyotropic series. Chaotropic salts protect against ethanol-induced deactivation and antichaotropic salts enhance the rate of this process. It is proposed that the mechanism by which chaotropic solutes exert their protective effect involves a reduction in the activity coefficient of the ethanol, thereby reducing the concentration of ethanol within the plasma membrane.

The logical status of brain death criteria

This article is an attempt to clarify a confusion in the brain death literature between logical sufficiency/necessity and natural sufficiency/necessity. We focus on arguments that draw conclusions regarding empirical matters of fact from conceptual or ontological definitions. Specifically, we critically analyze arguments by Tom Tomlinson and Michael B. Green and Daniel Wikler, which, respectively, confuse logical and natural sufficiency and logical and natural necessity. Our own conclusion is that it is especially important in discussing the brain death issue to observe the distinction between logical and natural sufficiency/necessity in a strict fashion.

Identifiable pharmacokinetic models: the role of extra inputs and measurements

Single input, single output experiments can result in nonunique solutions for the rate constants to a linear compartmental model used to describe the pharmacokinetics. Where a finite number of solutions exists, a priori knowledge has to be used to distinguish between the solutions. Where there is a infinite number of solutions, assumptions have to be made about the values of some rate constants in order to obtained a unique solution for the other. This paper considers such experiments and determines whether either the addition of an extra input (simultaneously with the first input) or the taking of an extra measurement would result in a unique solution. It is found that perturbing a second input can be useful, but only if the perturbation is of different shape from the first input. Measurements of drug in urine and metabolite in plasma are generally not helpful in resolving identifiability of the drug dynamic model. If a radioactive tracer is used, through, the second measurement (for example, by externally scanning the radioactivity of the liver) can prove useful, but only if the gain of the measuring device is known.

Acute bilateral anterior dislocation of the shoulders

In 3 cases of simultaneous bilateral anterior dislocation of the shoulders, considering the forces which predispose to anterior dislocations, it is postulated that in each case forced abduction and external rotation or abduction with hyperextension causes these injuries to occur.