Introduction Oesophageal adenocarcinoma presents an ever increasing challenge to the NHS, with rising incidence and poor overall survival. There are few robust biomarkers available for this disease – either for detection or stratification. Barrett’s Oesophagus, a precursor to adenocarcinoma, is common. In the non-dysplastic setting, few patients will progress to cancer. There are no current biomarkers to aid in this stratification process. Aims To assess the role of methylation biomarkers in the context of diagnosis of adenocarcinoma and their role in tumour biology. To provide a methylation stratification tool in the identification of high risk non-dysplastic Barrett’s Oesophagus. Methods Genome wide methylation assessment was performed with validation using bisulphite pyrosequencing on carefully selected tissues to reveal novel methylation biomarkers Results Methylation of TRIM15, has been shown to be a robust biomarker in disease identification and has a role in tumour biology. OR3A4, a long none coding RNA, has been identified as a way to reliably risk stratify the non-dysplastic Barrett’s patient and forms the first biomarker of this kind. Conclusions Methylation biomarkers play a key role in disease identification and risk of cancer development. They also appear to play a role in tumour biology.

This thesis proved that chest wall motion analysis technology could be used in thoracic surgery to answer a number of clinical and physiological questions. We used it either as a diagnostic tool or for the evaluation of an intervention outcome. We divided its use as a diagnostic tool into two categories; 1- diagnosis before surgery and 2- diagnosis after surgery. In the evaluation of an intervention outcome, we divided its use after a number of interventions: 1. Cosmetic Surgery: Chapter 5: The Effect of Pectus Carinatum (Pigeon Chest) Repair on Chest Wall Mechanics 2. Prognostic Surgery: a) Chapter 4: The Effect of Chest Wall Reconstruction on Chest Wall Mechanics b) Chapter 10: Late Changes in Chest Wall Mechanics Post Lung Resection: The Effect of Lung Cancer Resection In COPD patients 3. Palliative Surgery: a) Chapter 6: The Effect of Lung Volume Reduction Surgery on Chest Wall Mechanics b) Chapter 3: The Effect of Diaphragmatic Plication (Fixation) on Chest Wall Mechanics 4. Post-operative Intervention: Chapter 8: The Effect of Thoracic Nerve Blocks on Chest Wall Mechanics.

Serotonin (5-HT) is a neurotransmitter that is mainly expressed in brain where serves a wide array of physiological and behavioural functions. Literature described that some mediators of inflammation (i.e. cytokines) have been implicated in the modulation of monoaminergic response and this may be associated with pathophysiology of depression and in the responsiveness of antidepressant treatment in both humans and animals (Capuron and Miller, 2011). A hypothesis suggests that cytokines may affect the serotonergic system through p38 MAP kinase dependent mechanisms particularly at the serotonin transporters (Zhu et al., 2006) and 5HT7 receptors (Lieb et al., 2005; Mahe et al., 2005). The aim of this study was to show the interaction of Interleukin 1β (IL-1β) or p38 MAP kinase on serotonin transporter (SERT) and 5HT7 receptors in cells lines and native tissue, highlighting the biochemical mechanism of this system. The IL-1β and p38 MAP kinase activator, anisomycin, did not show any effect on 5-HT uptake and p38 MAPK activation in rodent native brain tissue, in human platelets and in cell lines in contrast to literature reports (Zhu et al.,2010). A different method was then used in which a release of cytokines was induced directly in the rat brain through an i.c.v. LPS treatment. Although proinflammatory cytokines involved in the change of animal mood, such as IL-1ß and TNFα, showed a significant increase in cortex and striatum, a modulation of SERT activity in term of Km and Vmax was not detected, confirming again that no interaction between cytokines, p38 MAP kinase and SERT function in vitro nor in vivo was evident. In contrast, this study revealed a positive interaction between 5HT7 receptors and p38 MAP kinase in glia cells. However, this pathway was not present in cortical neurons where 5HT7 receptors did not activate p38 MAP kinase but instead increased the AMPAR subunit, GluR1 and CREB phosphorylation. The effect on GluR1 was reversed by the specific 5HT7 antagonist, SB258719, and the PKA inhibitor, H89, confirming the specificity of response for 5HT7 receptors and the involvement of PKA in the mediation of GluR1 phosphorylation. In conclusion, this study displayed a lack of interaction between IL-1β and p38 MAP kinase on rat SERT while highlighting the effect of 5HT7 receptors on p38 MAP kinase, with different functions between glial and neuronal cells. Noteworthy, this is the first report that showed a positive interaction between 5HT7 receptors and AMPA which stimulates new investigation into the role of 5HT7 receptors in neuronal plasticity.

Heart transplantation provides a substantial survival benefit for selected patients with advanced heart failure, achieving a 1 year survival rate of ≥80%. Up to two thirds of hearts offered for transplantation are rejected before detailed organ inspection as being likely to fail if transplanted. The decision to discount these organs is based on clinical factors (e.g. blood pressure, electrocardiographic changes, prior cardiopulmonary resuscitation, drug history, history of hypertension and the need for inotropic support). However, none of these factors necessarily preclude successful transplantation. Thus, there is a pool of unused hearts, for which permission for heart donation has been granted, from which additional transplants could be generated if we could be more confident about their current and future function. My research prospectively validated a definition of primary allograft dysfunction following heart transplantation that is suitable for use in multicentre studies. I then investigated the role of biomarkers in the evaluation of potential cardiac donors with objective of increasing the number of donor hearts that will be assessed by direct inspection. This lead to the design of a scoring system to guide donor evaluation.

Background: Healthcare policy encourages the use of scientific evidence in clinical practice. The complex reality of practice means that dissemination of this evidence in clinical guidelines is insufficient to change behaviour and reduce variation. This study took a knowledge mobilisation perspective to assess the role of evidence- based medicine in orthopaedic practice decisions for hip replacement surgery. Objectives: The research sought to identify where, when and how evidence and knowledge were used in decision-making and how this contributed to variation in practice. It discovered factors which influenced orthopaedic surgery decision-making through an in-depth exploration of real life evidence use in practice. Methods: Three in-depth case studies were conducted at NHS hospitals over 12-months. Data collected included 64 interviews with surgeons and NHS staff, observations of day-to-day practice and the collection of 121 supplementary documents. A case study road map method was performed using thematic analysis to generate four themes: individuals, groups, organisations and regulation. Results: The findings combined individuals and groups, the organisational dynamics and environmental regulation to provide a nuanced understanding of knowledge mobilisation in orthopaedics. Group level knowledge was crucial in explaining variation to evidence based medicine, specifically how it influenced organisational capacity and the socialisation of medical professionals. The characteristics of surgeons also contributed to the wider definition of evidence which was important for clinical decisions. Conclusion: This empirical study of knowledge mobilisation demonstrated that orthopaedic practice was contingent and mediated at different levels, each of which contributed to variation. Decision-making was dependent on a range evidence and knowledge sources that were influential across the entire knowledge domain. A conceptual framework was produced to demonstrate how knowledge is mobilised in a highly professionalised organisationally regulated context.

Introduction Feedback is important for change in clinical practice. In the postgraduate clinical workplace opportunities for feedback are sporadic and non-standardised. Workplace Based Assessments were designed to offer trainees and trainers the opportunities to engage in feedback. WBA have a role as an assessment of learning and in practice settings the educational benefits of WBA remain elusive. Research question; How do WBA impact on feedback interactions, between surgical trainers and trainees, in the postgraduate workplace? Methods This mixed methods study adopted an explanatory sequential approach to data collection and analysis. Quantitative, questionnaire data, guided qualitative, focus group, data collection and analysis. Results Trainees perceive WBA represent an assessment of learning compared to trainers. Trainers perceive they provide feedback to trainees more than trainees perceive receiving it. Trainees actively engage in seeking feedback via WBA and this relates to perceptions of the value of feedback, having a learning goal orientation and effective supervision. Trainees’ perception of WBA as an assessment of learning leads them to “play the game” and seek positive feedback and avoid negative feedback in the context of WBA. Outside of WBA trainees seek negative feedback which they use to change practice. Trainers described that the culture of WBA, the purpose of WBA as an assessment for learning and of learning, how WBA are used (properly v playing the game) and the trainer – trainee relationship are all interwoven. Activity Theory can illuminate the complex clinical dynamic in which feedback interactions take place. Discussion Feedback interactions in the context of WBA in the postgraduate workplace are highly complex. Trainees and trainers play an active role in these interactions and can choose to engage in meaningful feedback exchanges using WBA. Trainees concerns about the assessment for learning role of WBA adversely affects how WBA are used by trainees and subsequently trainers.

Background: Chronic low back pain (CLBP) is a highly prevalent condition that has substantial impact on patients, the healthcare system and society. Its aetiology is complex and the condition can be exacerbated by many psychological, physical and social factors. Pain management services (PMS), which aim to address the complex nature of back pain, are recommended in clinical practice guidelines to manage CLBP. Although the effectiveness of such services has been widely investigated in relation to CLBP, the quality of evidence underpinning the use of these services remains moderate. Given that these services are resource intensive, evidence is needed to determine their cost-effectiveness. Aim: This study aims to describe the patient characteristics, clinical outcomes and healthcare resource use of people with CLBP in a community-based pain management service (PMS) in Nottingham to derive an indicative estimate of the cost effectiveness of PMS compared with standard care (SC). Methods: The study followed the Medical Research Council (MRC) guidance for evaluating complex interventions. The MRC suggest conducting developmental and observational work before evaluating complex interventions on a larger scale. Therefore, this PhD research includes a service evaluation study, which was conducted in two community-based PMS in Nottingham. This was followed by a systematic review of the cost effectiveness of a PMS in CLBP. Finally, a decision analysis model was developed to assess the cost effectiveness of PMS compared with SC. In the service evaluation study, newly referred people with CLBP who provided written consent were included. Participants provided information on health status and healthcare resource use using postal questionnaires and diaries at baseline and then three and six months after recruitment. The outcome measures were the Brief Pain Inventory (BPI), the Roland Morris Disability Questionnaire (RMDQ) and the EuroQoL (EQ-5D-3L). In the systematic review, electronic searches were conducted in clinical and economic databases from their inception to August 2017. Full economic evaluations, undertaken from any perspective, conducted alongside randomised clinical trials (RCTs) or based on decision analysis models were included. The Cochrane Back Review Group (CBRG) risk assessment and the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist were used to assess the methodological quality of eligible studies. These studies informed the development of an economic evaluation based on a decision analysis model to compare PMS with SC. Costs per extra quality-adjusted-life-year (QALY) were calculated from the UK National Health Service (NHS) England perspective using a lifetime horizon. Transition probability, utilities, healthcare resource use and costs were obtained from the service evaluation study and the published literature. Results: In the service evaluation study, 32 people were recruited over 10 months. The mean age was 58.8 years with an equal distribution of both genders. The dropout rates were 21% and 25% over three and six months respectively. Disability was measured using RMDQ (with a score range between 0-24), where higher scores mean more disability. The mean score at baseline was 13.5, after three and six months the means were 11.9 and 11.1 respectively. The BPI was used to measure pain intensity and interference. The scores ranged from 0 to 10, where higher scores mean more pain. The mean score for pain intensity was 5.9 at baseline, followed by a mean of 5.5 and 5.6 at three and six months respectively, whereas pain interference was 5.9 at baseline, followed by a mean of 5.2 at three and six months. As for the EQ5D-3L, higher scores in EQ5D means better health states. The mean score was 0.38 at baseline and, after three and six months, the scores were 0.46 and 0.40 respectively. The mean number of health visits per patient between baseline and three months was 4, whereas between four and six months the mean number of visits per patient was 2.9. In the systematic review, five studies fulfilled the eligibility criteria. The PMS varied significantly between studies in terms of the number of treatment modalities, intensity and the duration. The PMS was compared with either standard care, which varied according to the country and the setting or with two different surgical interventions. In this review, three out of five studies had a high risk of bias based on the design of the randomised controlled trials (RCTs). In addition, there were limitations in the statistical and sensitivity analyses in the economic evaluations. Therefore, the results from this systematic review need to be interpreted with caution. Finally, the indicative economic evaluation showed thatthe PMS was both more effective and more costly compared with SC. The mean incremental cost effectiveness ratio (ICER) was £761.43 and £706.98 per quality adjusted life years (QALY) gained in the deterministic and probabilistic analyses, respectively. At a ceiling willingness to pay (WTP) of £20,000, the PMS reaches a 51% probability of being cost-effective. This suggest that there is 51% probability that the PMS is both more effective and less costly. The incremental net monetary benefit generated a mean of £7884.07, indicating that the PMS is cost-effective compared with the SC at a WTP of £20,000. In the sensitivity analysis, the results were affected by changing the utility score for severe pain and increasing the initial cost of the intervention. In the scenario analysis, the incremental cost and QALYs were in favour of the PMS for people with severe pain at baseline. The probability of the PMS being cost effective for people with severe pain was 54%. In addition, the sustained reduction in treatment effect reduces the PMS probability of being cost effective to 48%. Finally, using the two months’ data to generate the transition probabilities demonstrated that PMS dominates the SC and the probability of the PMS being cost effective was 58% Conclusion: Community-based PMS have the potential to improve functional disability and pain interference for people with CLBP in primary care by providing well-timed access to a specialised pain management team, ensuring effective use of pain medicines and streamlining the treatment pathways based on the individual patient’s needs. A systematic literature review highlighted inconsistent evidence supporting PMS. The cost effectiveness studies included in this systematic review were alongside RCTs with a maximum follow up period of two years. As a result of the limitations of this type of economic evaluation, a decision analysis model was developed in order to assess the life time effectiveness of PMS compared with SC. The decision analysis model showed that PMS is more effective and costly compared with SC in the base case analysis; however, changing the source of transition probabilities from 12 months to two months demonstrated that PMS dominated SC, providing the potential for PMS to be cost-effective if high quality research is conducted to reduce the uncertainty around transition probabilities. The results were also sensitive to change in the utility score for severe pain, the initial cost of the PMS and using the PMS for people with severe pain at baseline. Therefore, further information is needed to assess the uncertainties in these parameters to provide a more robust estimate of the cost-effectiveness of PMS compared with SC.

Colorectal cancer is the second most common cause of cancer death in the western world. Despite improvements in diagnosis and treatment, 50% of patients still die from this disease. It is now recognised that postoperative infective complications contribute to poor cancer specific survival following resection for colorectal cancer. The basis of this observation is not clear. One hypothesis is that the presence of a raised systemic inflammatory response may be responsible. Whether a raised postoperative inflammatory response is the result of an early underlying infection at a preclinical stage, or whether a raised inflammatory response leads to increased susceptibility to subsequent infection is not known. If the former proves true, it is possible that targeting at risk patients with pre emptive antibiotics may reduce infective complications and improve patient outcomes. Conversely, if the latter is the case, perioperative intervention to reduce the postoperative inflammatory response may reduce infective complications and hence improve outcomes, both short and long term, for patients undergoing colorectal cancer resection. The work presented in this thesis further examines the relationship between the systemic inflammatory response and postoperative infective complications following resection for colorectal cancer, determines predictive thresholds for the development of postoperative infective complications, assesses the impact of the peak systemic inflammatory response on these thresholds and investigates the determinants of the peak response. Finally, the question as to whether a raised postoperative systemic inflammatory response is the cause or consequence of infective complications is examined.

Colorectal cancer is the second commonest cause of cancer-related death after lung cancer. Prognostic features of colorectal cancer are important in determining the optimal treatment for an individual patient. The management of colorectal cancer is further complicated by the need to translate prognosis based on morphology alone as the TNM staging system describes only the anatomical extent of colorectal cancer. However, there are other prognostic factors that have impact on disease progression and can be used as adjuncts to the TNM classification. In particular, features of invasiveness of the tumour may be helpful in the identification of an aggressive phenotype of colorectal cancer and were further investigated. The hypothesis of an aggressive phenotype of colorectal cancer was explored; tumour budding reflects a detachment of tumour cells at the invasive front and presumed to be an early step in the metastatic process. As such, tumour budding has received some attention in colorectal cancer as it has been proposed as an additional factor that may stratify patients into risk categories and therefore considered to be a promising prognostic factor in colorectal cancer. Chapter 2 examined lymphatic invasion (LI) and blood vessel invasion (BVI) in context to the feasibility of methods in routine practice with and without immunohistochemistry. Results suggested the use of immunohistochemistry (IHC) for detection of lymphatic invasion as feasible; D2-40 improved the identification of lymphatic invasion and was associated with N stage. Elastica staining improved detection rates of blood vessel invasion was associated with T stage and had independent prognostic value. However, the usefulness of CD31 could not be demonstrated. 2 Thus, immunostaining with D2-40 as predictor of nodal metastasis has potential as a marker of lymph node metastasis in early stage colorectal cancer. The detection of blood vessel invasion appeared to be optimised by utilising Elastica stain, resulting in improved detection rates and improved prediction of survival. Therefore, the routine use of Elastica was recommended. These results also point to the relative roles of lymphatic and blood vessel invasion in tumour progression and dissemination in patients with colorectal cancer. In Chapter 3, Elastica staining in blood vessel invasion was further investigated. In study A, the impact of Elastica staining was examined by comparing two cohorts of patients before and after the routine implementation of the stain. Despite that Elastica staining has been shown to enhance detection rates of venous invasion with improved stratification of risk for patients with colorectal cancer, the Royal College of Pathologists advise its routine use only as a measure of quality control if venous detection rates are below 30%. Results from this study concluded that detection of venous invasion appeared to be optimised by utilising Elastica/ H&E stain that resulted in improved detection rates and improved prediction of survival. The routine use of Elastica/ H&E staining was therefore recommended. In study B, venous invasion in mouse models based on the most common mutated genes of colorectal cancer were examined. Evaluation of the depth of invasion (T stage) was used as an indicator of the extent of tumour growth and venous invasion was used as indicator of metastatic spread. The results showed that Elastica staining can be of use in the assessment of mouse models as it highlighted the elastin in veins and vascular structures were recorded in all models. However, venous invasion was only present in model 2 suggesting the 3 metastatic potential of this model. Therefore, in Model 2 the addition of activated Kras promoted formation of invasive tumours. Kras has a known role in metastatic colorectal cancer. Therefore, Elastica staining can be used to contribute to the current understanding of metastatic spread in colorectal cancer. Chapter 4 examined tumour invasion in nerves as a potential supplement to the TNM staging system. Metastatic spread can occur in nerves however, the identification of perineural invasion can be difficult with routine staining -H&E (haematoxylin and eosin) alone. Therefore, the prognostic role of perineural invasion (PNI) in Stage I colorectal cancer, using immunohistochemical staining (S100) was investigated. No associations were demonstrated between perineural invasion and clinopathological features. However, the combination of venous invasion and perineural invasion (VI&PNI) were associated with poorer overall survival on univariate analysis while age had independent prognostic value. Therefore, immunohistochemistry using S100 improved the identification of perineural invasion however, alone; the prognostic value was limited unless used in combination with venous invasion. These findings suggested that the detection of early metastatic invasion (Venous/lymphatic/perineural invasion- ―VELIPI‖) in Stage I colorectal cancer can potentially be helpful in the prediction. In Chapter 5 tumour budding were further investigated. First, the prognostic value of tumour budding using of the 10HPF (high powered field) method were examined. H&E slides were used and the number of tumour buds was counted using the 10HPF method. An optimal threshold score for the determination of high-grade budding was performed by a ROC analysis using survival as endpoint. 4 The study concluded that the presence of tumour budding was an independent adverse prognostic factor in patients with primary operable colorectal cancer. Therefore, the 10HPF method demonstrated to be a promising method for the assessment of tumour budding in H&E sections and should be considered for implementation in routine clinical practice. Next , the relationship between tumour budding and clinopathological characteristics, tumour micro-environment and survival in patients with primary operable colorectal cancer were examined. Results showed that tumour budding was associated with TNM stage, serosal involvement, venous invasion and a weaker inflammatory cell infiltrate and more stroma. The study concluded that the presence of tumour budding was associated with elements of the tumour micro-environment and was an independent adverse prognostic factor in patients with primary operable colorectal cancer. Specifically, high tumour budding was associated with and stratified effectively the prognostic value of TNM stage, venous invasion and GMS. Taken together tumour budding should be assessed routinely in patients with primary operable colorectal cancer. Further, the prognostic significance of intratumoural budding were investigated, when compared to peritumoural budding in patients with primary operable colorectal cancer. Results showed that intratumoural budding was an independent prognostic factor, as such supporting further studies to investigate intratumoural budding in a larger cohort of preoperative biopsies applicable to routine clinical use. The work presented in this thesis highlights the importance of the additional factors associated with tumour invasiveness and reports associations with the tumour micro environment and local inflammation in patients with colorectal 5 cancer. In addition, this work adds weight to the body of evidence suggesting that the recognition of an aggressive phenotype may improve stratification of treatment for patients with colorectal cancer. The thesis concluded that additional prognostic factors associated with tumour invasiveness can contribute to the current TNM staging systems and have potential to be implemented with automated assessment for future use in routine practice, the implementation of tumour budding should be further explored.

This study aimed to comprehensively explore the relationship between psychological factors and pain, function and quality of life. A mixed method approach comprising two longitudinal and one cross-sectional elements, was conducted, with results being triangulated to give a multi-perspective view of the relationships. In the longitudinal elements, the questionnaire used in the quantitative phase was developed from validated tools, with cognitive interviews incorporating a think-aloud technique, used to validate the questionnaire package. Diary and interview schedules for the qualitative phase were developed from the existing literatures in this field. Additionally, a cross-sectional review of the pre-operative education programme in five centres was examined through participant observation. One-hundred and five patients scheduled for initial assessment were recruited into the quantitative phase. Of these, thirty-nine were successfully recruited to the quantitative phase and sixteen were followed up at six months post-operative. Twelve of the participants in the quantitative phase also participated in the qualitative phase, with five being successfully followed up at six months post-operative. Results indicated that pain, function and quality of life were highly associated with self-efficacy, pain catastrophising, functional expectations, pre-operative depression, post-operative anxiety and post-operative negative affect. The qualitative element identified five themes: physical symptoms; management and awareness; support; well-being; and cognitive aspects of the self-regulatory model. Evaluation of the content of the education programme identified that all information provided to the patients was in line with the guidelines. Triangulation of the mixed methods identified the congruence of major relationships between pain, function and quality of life with self-efficacy and expectations in the longitudinal elements. Self-efficacy and expectations should be considered throughout the hip surgery journey. Interventions, such as use of a reflective diary and talking to former patients who have undergone hip replacement, will enhance self-efficacy and adjustment of expectations, thus promoting better pain control, functional recovery and helping to tackle negative emotions.