New Guinea has the world's richest island flora.

New Guinea is the world's largest tropical island and has fascinated naturalists for centuries1,2. Home to some of the best-preserved ecosystems on the planet3 and to intact ecological gradients-from mangroves to tropical alpine grasslands-that are unmatched in the Asia-Pacific region4,5, it is a globally recognized centre of biological and cultural diversity6,7. So far, however, there has been no attempt to critically catalogue the entire vascular plant diversity of New Guinea. Here we present the first, to our knowledge, expert-verified checklist of the vascular plants of mainland New Guinea and surrounding islands. Our publicly available checklist includes 13,634 species (68% endemic), 1,742 genera and 264 families-suggesting that New Guinea is the most floristically diverse island in the world. Expert knowledge is essential for building checklists in the digital era: reliance on online taxonomic resources alone would have inflated species counts by 22%. Species discovery shows no sign of levelling off, and we discuss steps to accelerate botanical research in the 'Last Unknown'8.

Strategies of diaspore dispersal investment in Compositae: the case of the Andean highlands.

BACKGROUND AND AIMS: Understanding diaspore morphology and how much a species invests on dispersal appendages is key for improving our knowledge of dispersal in fragmented habitats. We investigate diaspore morphological traits in high-Andean Compositae and their main abiotic and biotic drivers and test whether they play a role in species distribution patterns across the naturally fragmented high-Andean grasslands. METHODS: We collected diaspore trait data for 125 Compositae species across 47 tropical high-Andean summits, focusing on achene length and pappus-to-achene length ratio, with the latter as a proxy of dispersal investment. We analysed the role of abiotic (temperature, elevation and latitude) and biotic factors (phylogenetic signal and differences between tribes) on diaspore traits and whether they are related to distribution patterns across the Andes, using phylogenomics, distribution modelling and community ecology analyses. KEY RESULTS: Seventy-five percent of the studied species show small achenes (length <3.3 mm) and 67% have high dispersal investment (pappus length at least two times the achene length). Dispersal investment increases with elevation, possibly to compensate for lower air density, and achene length increases towards the equator, where non-seasonal climate prevails. Diaspore traits show significant phylogenetic signal, and higher dispersal investment is observed in Gnaphalieae, Astereae and Senecioneae, which together represent 72% of our species. High-Andean-restricted species found across the tropical Andes have, on average, the pappus four times longer than the achene, a significantly higher dispersal investment than species present only in the northern Andes or only in the central Andes. CONCLUSIONS: Small achenes and high diaspore dispersal investment dominate among high-Andean Compositae, traits typical of mostly three tribes of African origin; but traits are also correlated with the environmental gradients within the high-Andean grasslands. Our results also suggest that diaspore dispersal investment is likely to shape species distribution patterns in naturally fragmented habitats.

Protocol for the ORION trial (RadiO fRequency ablatION for haemorrhoids): a randomised controlled trial.

BACKGROUND: Haemorrhoids are common and can significantly impact the personal and working lives of individuals. Those with more severe symptoms and those not responding to conservative management may require surgery. Current surgical techniques are associated with a degree of postoperative discomfort which may delay return to normal activity. Recurrence is lower in more radical procedures but resulting pain is higher. Radiofrequency ablation (RFA) is a new technique that is gaining popularity and has several hypothesised benefits, including reduced pain and recurrence. However, available evidence is limited. A recent overview from the National Institute for Health and Clinical Excellence recommended more research, in the form of randomised controlled trials, be carried out before further investment is made by national health services. Our aim is to assess whether RFA is at least as good in terms of recurrence as existing surgical interventions, but superior in terms of pain, for patients with symptomatic grade II and III haemorrhoids. METHODS: The RadiO fRequency ablatION for haemorrhoids (ORION) trial will be a pragmatic multicentre patient/assessor-blind parallel group-controlled trial with economic evaluation. The target sample size is 376 participants (188 per arm) and is based on two co-primary endpoints: (i) a non-inferiority design for recurrence and (ii) superiority design for pain at seven days. Participants with grade II or III haemorrhoids will be recruited in 16 National Health Service hospitals and randomised (1:1) to either RFA or surgeon's choice of surgery. CONCLUSIONS: Results will inform future practice for the treatment of grade II-III haemorrhoids and provide evidence for national health services on future investments in RFA. TRIAL REGISTRATION: ISRCTN14474552.

The role of Kono-S anastomosis and mesenteric resection in reducing recurrence after surgery for Crohn's disease: a systematic review.

AIM: Recurrence after surgery for Crohn's disease is common. Anastomotic configuration may influence recurrence and the mesentery may be key. Recently the Kono-S anastomosis and radical mesenteric excision have been proposed as methods of reducing recurrence. We analysed the literature pertaining to these novel techniques. METHOD: We searched MEDLINE, Embase and the Cochrane Library for, and selected, studies evaluating Kono-S anastomosis and/or radical mesenteric excision in Crohn's disease. We assessed methodological quality and risk of bias using the Cochrane risk of bias tool for randomized controlled trials and the Joanna Briggs Institute tool for nonrandomized trials. A narrative synthesis was used to summarize the findings. RESULTS: Nine studies (896 patients) were identified. Apart from one randomized controlled trial with a low risk of bias the overall level of evidence was poor (Grade IV). The Kono-S anastomosis was associated with a lower incidence of endoscopic and surgical recurrence (0%-3.4% vs 15%-24.4% respectively). Complications, particularly anastomotic leak rate, were also lower (1.8% vs 9.3% respectively). Evidence from a single poor quality study suggested that mesenteric excision may reduce surgical recurrence rates compared with mesentery preservation. CONCLUSION: The existing literature suggests that the Kono-S anastomosis is safe and may reduce endoscopic and surgical recurrence, but level of evidence is mainly poor. One element of the Kono-S technique, preservation of the mesentery, may be detrimental to recurrence. Further, higher quality, studies are required to investigate these techniques. Such studies should consider the impact of the degree of mesenteric resection in addition to the anastomosis on disease recurrence.

A mapping review of sacrococcygeal pilonidal sinus disease.

BACKGROUND: Pilonidal sinus is a hole in the natal cleft which may cause severe pain and become infected. The evidence base for management of pilonidal sinus is said to be poor quality, poorly focused and rapidly proliferating. We undertook a systematic mapping review to provide a broad overview of the field and support the identification of research priorities. METHODS: We searched MEDLINE, CINAHL, and EMBASE from inception to 22nd Nov 2020 for primary research studies focused on the management of pilonidal sinus. We extracted data on study design and categorised studies under five major headings ('non-surgical treatment', 'surgical treatment', 'aftercare' and 'other'), producing frequency counts for different study designs. Gaps in research were identified from published systematic reviews and tabulated. RESULTS: We identified 983 eligible studies, of which 36 were systematic reviews and/or meta-analyses; 121 were randomised controlled trials), and 826 observational studies of various design. The majority of studies evaluated surgical techniques (n = 665), or adjuvant medical interventions (n = 98). The literature on wound care has developed most recently, and the evidence base includes 30% randomised controlled trials. Gaps analysis highlighted comparison of surgical techniques including flaps, laser depilation, and wound care interventions as potential areas for randomised controlled trials. CONCLUSIONS: This mapping review summarises eight decades of research on the management of pilonidal sinus. Further research is needed to identify front-running interventions, understand variation in practice and patient values, and to prioritise future research.

Non-randomized studies should be considered for assessing surgical techniques in rectal prolapse: prospective cohort study.

AIM: Randomized trials comparing surgical techniques for rectal prolapse are not always feasible. We assessed whether non-randomized comparisons of those who have had surgery with those still waiting would be confounding baseline health status. METHOD: This was a prospective cohort study in seven UK hospitals. Participants were ≥ 18 years and listed for surgical interventions of equivalent intensity for rectal prolapse. They were defined as short or long waiters (≤ 18 or > 18 weeks, respectively). Time on the waiting list was compared with baseline comorbidity (Charlson comorbidity index) and change from baseline in health status (EQ-5D-5L) at the time of surgery. RESULTS: In all, 203 patients were analysed. Median (interquartile range) waiting time was 13.7 weeks (8.1, 20.4) varying across sites. Baseline comorbidity was not an important predictor of waiting time. Median Charlson comorbidity index was 2 (0, 3) for short and 1 (0, 3) for long waiters. A change in waiting time by a week was associated with negligible improvement in the EQ-5D-5L index of 0.001 (95% CI -0.000 to 0.003, P = 0.106). CONCLUSION: Negligible change in patient reported health status while on the waiting list and lack of effect of comorbidities in influencing waiting time support the use of non-randomized pre-/post-studies to compare the effects of surgical interventions for rectal prolapse.

Establishing core outcome sets for gastrointestinal recovery in studies of postoperative ileus and small bowel obstruction: protocol for a nested methodological study.

INTRODUCTION: Gastrointestinal recovery describes the restoration of normal bowel function in patients with bowel disease. This may be prolonged in two common clinical settings: postoperative ileus and small bowel obstruction. Improving gastrointestinal recovery is a research priority but researchers are limited by variation in outcome reporting across clinical studies. This protocol describes the development of core outcome sets for gastrointestinal recovery in the contexts of postoperative ileus and small bowel obstruction. METHOD: An international Steering Group consisting of patient and clinician representatives has been established. As overlap between clinical contexts is anticipated, both outcome sets will be co-developed and may be combined to form a common output with disease-specific domains. The development process will comprise three phases, including definition of outcomes relevant to postoperative ileus and small bowel obstruction from systematic literature reviews and nominal-group stakeholder discussions; online-facilitated Delphi surveys via international networks; and a consensus meeting to ratify the final output. A nested study will explore if the development of overlapping outcome sets can be rationalized. DISSEMINATION AND IMPLEMENTATION: The final output will be registered with the Core Outcome Measures in Effectiveness Trials initiative. A multi-faceted, quality improvement campaign for the reporting of gastrointestinal recovery in clinical studies will be launched, targeting international professional and patient groups, charitable organizations and editorial committees. Success will be explored via an updated systematic review of outcomes 5 years after registration of the core outcome set.

Preoperative bowel stimulation prior to ileostomy closure to restore bowel function more quickly and improve postoperative outcomes: a systematic review.

AIM: Closure of a diverting ileostomy following restorative surgery is often associated with significant short-term morbidity and variable long-term bowel function. The aim of this systematic review was to investigate if preoperative stimulation of the defunctioned bowel restores bowel function more quickly after ileostomy closure and improves postoperative outcomes when compared with standard preoperative care. METHOD: MEDLINE, Embase, CENTRAL, Google Scholar and ClinicalTrials.gov were searched for studies evaluating preoperative bowel stimulation in patients with a temporary ileostomy after low anterior resection or ileal pouch-anal anastomosis, regardless of their design, publication type or language. Study selection, data extraction and study assessment were performed by one reviewer and verified by another. Study results were synthesized narratively. The GRADE approach was used to assess the quality of evidence. RESULTS: Eight studies involving a total of 267 participants were included. The studies had a moderate to high risk of bias and were of varying methodological quality. Preoperative stimulation of the defunctioned bowel reduced the time to postoperative restoration of bowel function and the length of hospital stay when compared with standard preoperative care. Other functional outcomes and postoperative complication rates were similar to those of standard preoperative care. The overall quality of evidence was very low. CONCLUSION: Despite these promising early results, there is insufficient high-quality evidence to recommend routine implementation of preoperative bowel stimulation in clinical practice. Nevertheless, there is no evidence suggesting that the intervention worsens outcomes or is unsafe, paving the way for rigorous assessment of effectiveness, acceptability and cost-effectiveness within the context of well-designed clinical trials.

A systematic review of classification systems for pilonidal sinus.

BACKGROUND: Pilonidal sinus disease (PSD) is a simple chronic inflammatory condition resulting from loose hairs forcibly inserted into vulnerable tissue in the natal cleft. It is an acquired disease with a slight familial tendency. There is no agreement on optimum treatment and the multitude of therapeutic options cannot be compared due to the lack of a universally adopted classification of the disease. The aim of our study was to perform a systematic review of the literature to determine how presentations of PSD are classified and reported. METHODS: A systematic review of the English language literature was undertaken searching studies published after 1980. RESULTS: Eight classification systems of PSD were identified. Most classification systems were based on anatomical pathology hypotheses. The location and number of sinuses were the main factors defining classification systems. No articles were retrieved that assessed the validity and/or reliability of the classification system employed. Furthermore, there was no evidence to suggest a correlation between prognosis outcome and subgroup. CONCLUSIONS: Based on the evidence available from the literature reviewed we have no recommendations regarding the use of the current classification of PSD. A well-recognised and practical classification system to guide clinical practice is required.

What is the evidence for the use of parenteral nutrition (PN) in critically ill surgical patients: a systematic review and meta-analysis.

BACKGROUND: Malnutrition is associated with poor outcomes in surgical patients and corrective enteral feeding may not be possible. This is a particular problem in the acute setting where malnutrition is prevalent. The aim of this systematic review was to evaluate the use of parenteral nutrition (PN) in critically ill surgical patients. METHODS: This review was registered with PROSPERO (CRD42017079567). Searches of the CENTRAL, EMBASE, and MEDLINE databases were performed using a predefined strategy. Randomised trials published in English since 1995, reporting a comparison of PN vs any comparator in a critically ill surgical population were included. The primary outcome was mortality. Risk of bias was assessed using the Cochrane risk of bias tool and the Grading of Recommendations Assessment, Development and Evaluation assessment. Meta-analysis was performed using a random effects model to assess variation in mortality and length of stay. RESULTS: Fourteen RCTs were identified; standard PN was compared vs other forms of PN in ten studies, to PN with variable dose amino acids in one, and to enteral nutrition (EN) in three. In trials comparing glutamine-supplemented PN (PN-GLN) to PN, a non-significant reduction in mortality was noted (risk difference - 0.08. 95% CI - 0.17, 0.01, p = 0.08). A trend for a reduction in length of stay was seen in PN-GLN to PN comparator (mean reduction - 2.4, 95% CI - 7.19 to 2.32 days, I2 = 92%). Impact on other outcome measures varied in direction of effect. CONCLUSIONS: PN may offer benefit in critically ill surgical patients. The size and quality of studies lead to uncertainty around the estimates of clinical effect, meaning a robust trial is required.

Prognostic factors affecting outcomes in fistulating perianal Crohn's disease: a systematic review.

BACKGROUND: One in three patients with Crohn's disease will develop a perianal fistulae, and one third of these will achieve long-term healing or closure. A barrier to conducting well-designed clinical trials for these patients is a lack of understanding of prognostic factors. This systematic review sets out to identify factors associated with prognosis of perianal Crohn's fistulae. METHODS: This review was registered on the PROSPERO database (CRD42016050316) and conducted in line with PRISMA guidelines along a predefined protocol. English-language studies assessing baseline factors related to outcomes of fistulae treatment in adult patients were included. Searches were performed on MEDLINE and Embase databases. Screening of abstracts and full texts for eligibility was performed prior to extraction of data into predesigned forms. Bias was assessed using the QUIPS tool. RESULTS: Searches identified 997 papers. Following removal of duplicates and secondary searches, 923 were screened for inclusion. Forty-seven papers were reviewed at full-text level and 13, 2 of which were randomised trials, were included in the final qualitative review. Two studies reported distribution of Crohn's disease as a prognostic factor for healing. Two studies found that CARD15 mutations decreased response of fistulae to antibiotics. Complexity of fistulae anatomy was implicated in prognosis by 4 studies. CONCLUSIONS: This systematic review has identified potential prognostic markers, including genetic factors and disease behaviour. We cannot, however, draw robust conclusions from this heterogeneous group of studies; therefore, we recommend that a prospective cohort study of well-characterised patients with Crohn's perianal fistulae is undertaken.

Interventions for Managing Late Gastrointestinal Symptoms Following Pelvic Radiotherapy: a Systematic Review and Meta-analysis.

AIMS: Pelvic radiotherapy can induce gastrointestinal injury and symptoms, which can affect quality of life. We assessed interventions for managing these symptoms. MATERIALS AND METHODS: A review of randomised controlled trials published between January 1990 and June 2023 from databases including MEDLINE, EMBASE, CENTRAL, CINAHL, clinicaltrials.gov, ISRCTN and grey literature sources was conducted. Meta-analyses were carried out using the DerSimonian and Laird random effects model to produce overall treatment differences with 95% confidence intervals. RESULTS: Twenty-eight studies (2392 participants) of varying methodological quality were included. 4% formalin was superior to sucralfate for improving gastrointestinal symptom score (standardised mean difference [SMD] -1.07, 95% confidence interval -1.48 to -0.65). Argon plasma coagulation (APC) was inferior to sucralfate (SMD 1.22, 95% confidence interval 0.84 to 1.59). Counselling positively influenced symptom score (SMD -0.53, 95% confidence interval -0.76 to -0.29), whereas hyperbaric oxygen therapy showed conflicting results. Sucralfate combined with APC increased endoscopic markers of moderate-severe bleeding versus APC alone (risk ratio 2.26, 95% confidence interval 1.12 to 4.55). No definite conclusions on pain, incontinence, diarrhoea, tenesmus or quality of life interventions were confirmed. CONCLUSIONS: Small study sizes, methodological quality and heterogeneity limit support of any individual intervention. APC and 4% formalin seem to be promising interventions, with further larger randomised controlled trials now warranted.

Commentary: Core Descriptor Sets Using Consensus Methods Support 'Table One' Consistency.

Inconsistent reporting of patient characteristics in clinical research hampers reproducibility and limits analysis opportunities. This paper proposes condition-specific 'Core Descriptor Sets'(CDSs) comprising key factors like demographics, disease severity, comorbidities, and prognosis to standardise Table 1 reporting. Development entails stakeholder involvement, systematic identification of descriptors, value rating, and consensus-building using multiple Delphi rounds. Final agreement comes at an expert meeting. Benefits include easier cross-study comparison for example through individual patient meta-analysis, facilitated by comparison of consistently reported individual data rather than group level analysis. This may also support routine data analyses, subgroup and risk identification, and reduced research waste. CDSs describe cohorts thoroughly while minimising research burden. They are intended to enable improved clinical characterisation, personalisation, reproducibility, data sharing and knowledge building.

A Taxonomically-verified and Vouchered Checklist of the Vascular Plants of the Republic of Guinea.

The Checklist of the Vascular Plants of the Republic of Guinea (CVPRG) is a specimen-based, expert-validated knowledge product, which provides a concise synthesis and overview of current knowledge on 3901 vascular plant species documented from Guinea (Conakry), West Africa, including their accepted names and synonyms, as well as their distribution and status within Guinea (indigenous or introduced, endemic or not). The CVPRG is generated automatically from the Guinea Collections Database and the Guinea Names Backbone Database, both developed and maintained at the Royal Botanic Gardens, Kew, in collaboration with the staff of the National Herbarium of Guinea. A total of 3505 indigenous vascular plant species are reported of which 3328 are flowering plants (angiosperms); this represents a 26% increase in known indigenous angiosperms since the last floristic overview. Intended as a reference for scientists documenting the diversity and distribution of the Guinea flora, the CVPRG will also inform those seeking to safeguard the rich plant diversity of Guinea and the societal, ecological and economic benefits accruing from these biological resources.

Age-related hearing loss and mild cognitive impairment: a meta-analysis and systematic review of population-based studies.

BACKGROUND: The aim of this study was to identify any relationship between hearing loss and mild cognitive impairment. METHOD: This was a systematic review and meta-analysis of randomised controlled trials conducted using Medline and the Cochrane Library up to 24 June 2020. Prospective, cohort and cross-sectional, and observational studies that reported on the relationship between mild cognitive impairment and hearing loss were included. RESULTS: A total of 34 studies reporting data on 48 017 participants were included. Twenty-three studies observed a significant association between hearing loss and mild cognitive impairment. The pooled risk ratio across all studies of prevalence of mild cognitive impairment in people with hearing loss was 1.44 (random-effects; 95 per cent CI = 1.27-1.64; p < 0.00001; I2 = 0 per cent). Significantly more people with mild cognitive impairment had peripheral hearing loss compared with those without (risk ratio, 1.40 random-effects; 95 per cent CI = 1.10-1.77; p = 0.005; I2 = 0 per cent). When the incidence was studied, significantly more people with peripheral hearing loss had mild cognitive impairment compared with those without (risk ratio = 2.06 random-effects; 95 per cent CI = 1.35-3.15; p = 0.0008; I2 = 97 per cent); however; a high level of statistical heterogeneity was evident. CONCLUSION: Most of the studies included in this systematic review observed a significant association between hearing loss and mild cognitive impairment.

Antioxidants in the chemoprevention of colorectal cancer and colorectal adenomas in the general population: a systematic review and meta-analysis.

AIM: Antioxidants, such as vitamin A, C and E, selenium and ß-carotene, have been proposed as possible agents in the chemoprevention of colorectal cancer and have been the subject of recent trials and reviews. This review aimed to assess the present evidence on the effect of antioxidants on the incidence of colorectal neoplasms in the general population. METHOD: A systematic review of randomized controlled trials was undertaken comparing antioxidants alone or in combination with other agents vs placebo. The following databases were searched for published and unpublished literature: Cochrane Library, MEDLINE, PreMEDLINE, CINAHL, EMBASE, Web of Science, and Biological Abstracts and Research Registers. Studies were quality appraised and extracted. Meta-analysis was performed. RESULTS: Twelve studies were identified as relevant. In the nine comparing antioxidants with no antioxidants (n=148 922), there was no difference in the incidence of colorectal cancer [relative risk (RR) 1.00, 95% confidence interval (CI) 0.88-1.13]. One study assessed the effect of antioxidants on adenoma formation (n=15 538) and did not demonstrate a statistically significant effect (RR 1.47, 95% CI 0.97-2.23). Of 14 discrete analyses for different combinations of antioxidants, only one reported a statistically significant increase in relative risk of adenoma formation in participants receiving vitamin E (RR 1.74, 95% CI 1.09-1.79, P=0.02) or vitamin E plus ß-carotene (RR 1.63, 95% CI 1.01-2.63, P=0.04). Effectiveness did not seem to differ between healthy populations, participants with cardiovascular risk factors or populations exposed to smoking or asbestos. CONCLUSION: The review demonstrates that antioxidants (vitamin A, C and E, selenium and ß-carotene), as single agents, in combination with other antioxidants or in combination with other agents, are not effective in the chemoprevention of colorectal neoplasia in the general population. This questions their involvement in future randomized controlled trials of chemoprevention in colorectal cancer.

Development of an intervention to increase adherence to nebuliser treatment in adults with cystic fibrosis: CFHealthHub.

BACKGROUND: Cystic fibrosis (CF) is a life-limiting genetic condition in which daily therapies to maintain lung health are critical, yet treatment adherence is low. Previous interventions to increase adherence have been largely unsuccessful and this is likely due to a lack of focus on behavioural evidence and theory alongside input from people with CF. This intervention is based on a digital platform that collects and displays objective nebuliser adherence data. The purpose of this paper is to identify the specific components of an intervention to increase and maintain adherence to nebuliser treatments in adults with CF with a focus on reducing effort and treatment burden. METHODS: Intervention development was informed by the Behaviour Change Wheel (BCW) and person-based approach (PBA). A multidisciplinary team conducted qualitative research to inform a needs analysis, selected, and refined intervention components and methods of delivery, mapped adherence-related barriers and facilitators, associated intervention functions and behaviour change techniques, and utilised iterative feedback to develop and refine content and processes. RESULTS: Results indicated that people with CF need to understand their treatment, be able to monitor adherence, have treatment goals and feedback and confidence in their ability to adhere, have a treatment plan to develop habits for treatment, and be able to solve problems around treatment adherence. Behaviour change techniques were selected to address each of these needs and were incorporated into the digital intervention developed iteratively, alongside a manual and training for health professionals. Feedback from people with CF and clinicians helped to refine the intervention which could be tailored to individual patient needs. CONCLUSIONS: The intervention development process is underpinned by a strong theoretical framework and evidence base and was developed by a multidisciplinary team with a range of skills and expertise integrated with substantial input from patients and clinicians. This multifaceted development strategy has ensured that the intervention is usable and acceptable to people with CF and clinicians, providing the best chance of success in supporting people with CF with different needs to increase and maintain their adherence. The intervention is being tested in a randomised controlled trial across 19 UK sites.

National prospective cohort study of the burden of acute small bowel obstruction.

Background: Small bowel obstruction is a common surgical emergency, and is associated with high levels of morbidity and mortality across the world. The literature provides little information on the conservatively managed group. The aim of this study was to describe the burden of small bowel obstruction in the UK. Methods: This prospective cohort study was conducted in 131 acute hospitals in the UK between January and April 2017, delivered by trainee research collaboratives. Adult patients with a diagnosis of mechanical small bowel obstruction were included. The primary outcome was in-hospital mortality. Secondary outcomes included complications, unplanned intensive care admission and readmission within 30 days of discharge. Practice measures, including use of radiological investigations, water soluble contrast, operative and nutritional interventions, were collected. Results: Of 2341 patients identified, 693 (29·6 per cent) underwent immediate surgery (within 24 h of admission), 500 (21·4 per cent) had delayed surgery after initial conservative management, and 1148 (49·0 per cent) were managed non-operatively. The mortality rate was 6·6 per cent (6·4 per cent for non-operative management, 6·8 per cent for immediate surgery, 6·8 per cent for delayed surgery; P = 0·911). The major complication rate was 14·4 per cent overall, affecting 19·0 per cent in the immediate surgery, 23·6 per cent in the delayed surgery and 7·7 per cent in the non-operative management groups (P < 0·001). Cox regression found hernia or malignant aetiology and malnutrition to be associated with higher rates of death. Malignant aetiology, operative intervention, acute kidney injury and malnutrition were associated with increased risk of major complication. Conclusion: Small bowel obstruction represents a significant healthcare burden. Patient-level factors such as timing of surgery, acute kidney injury and nutritional status are factors that might be modified to improve outcomes.

The use of irinotecan, oxaliplatin and raltitrexed for the treatment of advanced colorectal cancer: systematic review and economic evaluation.

OBJECTIVES: To evaluate three technologies for the management of advanced colorectal cancer: (1) first-line irinotecan combination [with 5-fluorouracil (5-FU)] or second-line monotherapy; (2) first- or second-line oxaliplatin combination (again, with 5-FU); and (3) raltitrexed, where 5-FU is inappropriate. To examine the role of irinotecan and oxaliplatin in reducing the extent of incurable disease before curative surgery (downstaging). SOURCES: Ten electronic bibliographic databases covering the period up to August 2004. METHODS: Searches identified existing studies of the effectiveness and economics of the technologies and any studies that evaluated any of the indications outlined above were included. Data were extracted and assessed generic components of methodological quality. Survival outcomes were meta-analysed. RESULTS: Seventeen trials were found, of varying methodological quality. Compared with 5-FU, first-line irinotecan improved overall survival (OS) by 2-4 months (p=0.0007), progression-free survival (PFS) by 2-3 months (p<0.00001) and response rates (p<0.001). It offered a different toxicity profile and no quality of life (QoL) advantage. However, second-line irinotecan compared with 5-FU improved OS by 2 months (p=0.035) and PFS by 1 month (p=0.03), and provided a better partial response rate, but with more toxicities and no QoL advantage. Compared with second-line best supportive care, irinotecan improved OS by 2 months (p=0.0001), had a different toxicity profile and maintained baseline QoL longer, but with no overall difference. The addition of oxaliplatin to second-line 5-FU is associated with a borderline significant improvement in overall survival (p<0.07); a significantly higher response rate (<0.0001); and more serious toxicities. There is no evidence for a significant difference in QoL. Schedules with treatment breaks may not reduce clinical effectiveness but reduce toxicity. The addition of oxaliplatin to second-line 5-FU also saw no improvement in OS (p<0.07), better PFS (by 2.1 months, p=0.0001), an 8.9% higher response rate (p<0.0001), more toxicities and no QoL advantage. There was no significant difference in OS or PFS between first-line irinotecan and oxaliplatin combinations except when 5-FU was delivered by bolus injection, when oxaliplatin provided better OS (p=0.032) and response rates (p=0.032), but not PFS (p=0.169). The regimens had different toxicity profiles and neither conferred a QoL advantage. When compared to 5-FU, raltitrexed is associated with no significant difference in overall or progression-free survival; no significant difference in response rates; more vomiting and nausea, but less diarrhoea and mucositis; no significant difference in, or worse QoL. Raltitrexed treatment was cut short in two out of four included trials due to excess toxic deaths. 5-FU followed by irinotecan was inferior to any other sequence. First-line irinotecan/5-FU combination improved OS and PFS, although further unplanned therapy exaggerated the OS effect size. Staged combination therapy (combination oxaliplatin followed by combination irinotecan or vice versa) provided the best OS and PFS, although there was no head-to-head comparison against other treatment plans. In the only trial to use three active chemotherapies in any staged combination, median OS was over 20 months. In another study, the longest median OS from a treatment plan using two active agents was 16.2 months. Where irinotecan or oxaliplatin were used with 5-FU to downstage people with unresectable liver metastases, studies consistently showed response rates of around 50%. Resection rates ranged from 9 to 35% with irinotecan and from 7 to 51% with oxaliplatin. In the one study that compared the regimens, oxaliplatin enabled more resections (p=0.02). Five-year OS rates of 5-26% and disease-free survival rates of 3-11% were reported in studies using oxaliplatin. Alone or in combination, 5-FU was more effective and less toxic when delivered by continuous infusion. Existing economic models were weak because of the use of unplanned second-line therapies in their trial data: the survival benefits in patients on such trials cannot be uniquely attributed to the allocated therapy. Consequently, the economic analyses are either limited to the use of PES (at best, a surrogate outcome) or are subject to confounding. Weaknesses in cost components, the absence of direct in-trial utility estimates and the limited use of sensitivity analysis were identified. Improvements to the methodologies used in existing economic studies are presented. Using data from two trials that planned treatment sequences, an independent economic evaluation of six plans compared with first-line 5-FU followed on progression by second-line irinotecan monotherapy (NHS standard treatment) is presented. 5-FU followed on progression by irinotecan combination cost 13,174 pounds per life-year gained (LYG) and 10,338 pounds per quality-adjusted life-year (QALY) gained. Irinotecan combination followed on progression by additional second-line therapies was estimated to cost 12,418 pounds per LYG and 13,630 pounds per QALY gained. 5-FU followed on progression by oxaliplatin combination was estimated to cost 23,786 pounds per LYG and 31,556 pounds per QALY gained. Oxaliplatin combination followed on progression by additional second-line therapies was estimated to cost 43,531 pounds per LYG and 67,662 pounds per QALY gained. Evaluations presented in this paragraph should be interpreted with caution owing to missing information on the costs of salvage therapies in the trial from which data were drawn. Irinotecan combination followed on progression by oxaliplatin combination cost 12,761 pounds per LYG and 16,663 pounds per QALY gained. Oxaliplatin combination followed on progression by irinotecan combination cost 16,776 pounds per LYG and 21,845 pounds per QALY gained. The evaluation suggests that these two sequences have a cost-effectiveness profile that is favourable in comparison to other therapies currently funded by the NHS. However, the differences in OS observed between the two trials from which data were taken may be a result of heterogeneous patient populations, unbalanced protocol-driven intensity biases or other differences between underlying health service delivery systems. CONCLUSIONS: Treatment with three active therapies appears most clinically effective and cost-effective. NHS routine data could be used to validate downstaging findings and a meta-analysis using individual patient-level data is suggested to validate the optimal treatment sequence.