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While the key aspects of genetic evolution and their clinical implications in clear cell renal-cell carcinoma (ccRCC) are well-documented, how genetic features co-evolve with the phenotype and tumor microenvironment (TME) remains elusive. Here, through joint genomic-transcriptomic analysis of 243 samples from 79 patients recruited to the TRACERx Renal study, we identify pervasive non-genetic intratumor heterogeneity, with over 40% not attributable to genetic alterations. By integrating tumor transcriptomes and phylogenetic structures, we observe convergent evolution to specific phenotypic traits, including cell proliferation, metabolic reprogramming and overexpression of putative cGAS-STING repressors amid high aneuploidy. We also uncover a co-evolution between the tumor and the T cell repertoire, as well as a longitudinal shift in the TME from an anti-tumor to an immunosuppressive state, linked to the acquisition of recurrently late ccRCC drivers 9p loss and SETD2 mutations. Our study reveals clinically-relevant and hitherto underappreciated non-genetic evolution patterns in ccRCC.

Context: Immune-oncology strategies are revolutionising the perioperative treatment in several tumour types. The perioperative setting of renal cell carcinoma (RCC) is an evolving field, and the advent of immunotherapy is producing significant advances., Objective: To critically review the potential pros and cons of adjuvant and neoadjuvant immune-based therapeutic strategies in RCC, and to provide insights for future research in this field., Evidence Acquisition: We performed a collaborative narrative review of the existing literature., Evidence Synthesis: Adjuvant immunotherapy with pembrolizumab is a new standard of care for patients at a higher risk of recurrence after nephrectomy, demonstrating a disease-free survival and overall survival benefit in the phase 3 KEYNOTE-564 trial. Current data do not support neoadjuvant therapy use outside clinical trials. While both adjuvant and neoadjuvant immune-based approaches are driven by robust biological rationale, neoadjuvant immunotherapy may enable a stronger and more durable antitumour immune response. If neoadjuvant single-agent immune checkpoint inhibitors demonstrated limited activity on the primary tumour, immune-based combinations may show increased activity. Overtreatment and a risk of relevant toxicity for patients who are cured by surgery alone are common concerns for both neoadjuvant and adjuvant strategies. Biomarkers helping patient selection and treatment deintensification are lacking in RCC. No results from randomised trials comparing neoadjuvant or perioperative immune-based therapy with adjuvant immunotherapy are available., Conclusions: Adjuvant immunotherapy is a new standard of care in RCC. Both neoadjuvant and adjuvant immunotherapy strategies have potential advantages and disadvantages. Optimising perioperative treatment strategies is nuanced, with the role of neoadjuvant immune-based therapies yet to be defined. Given strong biological rationale for a pre/perioperative approach, there is a need for prospective clinical trials to determine clinical efficacy. Research investigating biomarkers aiding patient selection and treatment deintensification strategies is needed., Patient Summary: Immunotherapy is transforming the treatment of kidney cancer. In this review, we looked at the studies investigating immunotherapy strategies before and/or after surgery for patients with kidney cancer to assess potential pros and cons. We concluded that both neoadjuvant and adjuvant immunotherapy strategies may have potential advantages and disadvantages. While immunotherapy administered after surgery is already a standard of care, immunotherapy before surgery should be better investigated in future studies. Future trials should also focus on the selection of patients in order to spare toxicity for patients who will be cured by surgery alone., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Clear cell renal cell carcinoma (ccRCC) is the most common form of kidney cancer, but a comprehensive description of its genomic landscape is lacking. We report the whole genome sequencing of 778 ccRCC patients enrolled in the 100,000 Genomes Project, providing for a detailed description of the somatic mutational landscape of ccRCC. We identify candidate driver genes, which as well as emphasising the major role of epigenetic regulation in ccRCC highlight additional biological pathways extending opportunities for therapeutic interventions. Genomic characterisation identified patients with divergent clinical outcome; higher number of structural copy number alterations associated with poorer prognosis, whereas VHL mutations were independently associated with a better prognosis. The observations that higher T-cell infiltration is associated with better overall survival and that genetically predicted immune evasion is not common supports the rationale for immunotherapy. These findings should inform personalised surveillance and treatment strategies for ccRCC patients., (© 2024. The Author(s).)

Clear cell renal cell carcinoma (ccRCC) is the most common form of kidney cancer, but a comprehensive description of its genomic landscape is lacking. We report the whole genome sequencing of 778 ccRCC patients enrolled in the 100,000 Genomes Project, providing the most detailed somatic mutational landscape to date. We identify new driver genes, which as well as emphasising the major role of epigenetic regulation in ccRCC highlight additional biological pathways extending opportunities for drug repurposing. Genomic characterisation identified patients with divergent clinical outcome; higher number of structural copy number alterations associated with poorer prognosis, whereas VHL mutations were independently associated with a better prognosis. The twin observations that higher T-cell infiltration is associated with better outcome and that genetically predicted immune evasion is not common supports the rationale for immunotherapy. These findings should inform personalised surveillance and treatment strategies for ccRCC patients., Competing Interests: DECLARATION OF INTERESTS S.T. has received speaking fees from Roche, AstraZeneca, Novartis and Ipsen. ST has the following patents filed: Indel mutations as a therapeutic target and predictive biomarker PCTGB2018/051892 and PCTGB2018/051893 and Clear Cell Renal Cell Carcinoma Biomarkers P113326GB. None of the other authors have a conflict of interest.

Understanding the evolutionary pathways to metastasis and resistance to immune-checkpoint inhibitors (ICI) in melanoma is critical for improving outcomes. Here, we present the most comprehensive intrapatient metastatic melanoma dataset assembled to date as part of the Posthumous Evaluation of Advanced Cancer Environment (PEACE) research autopsy program, including 222 exome sequencing, 493 panel-sequenced, 161 RNA sequencing, and 22 single-cell whole-genome sequencing samples from 14 ICI-treated patients. We observed frequent whole-genome doubling and widespread loss of heterozygosity, often involving antigen-presentation machinery. We found KIT extrachromosomal DNA may have contributed to the lack of response to KIT inhibitors of a KIT-driven melanoma. At the lesion-level, MYC amplifications were enriched in ICI nonresponders. Single-cell sequencing revealed polyclonal seeding of metastases originating from clones with different ploidy in one patient. Finally, we observed that brain metastases that diverged early in molecular evolution emerge late in disease. Overall, our study illustrates the diverse evolutionary landscape of advanced melanoma., Significance: Despite treatment advances, melanoma remains a deadly disease at stage IV. Through research autopsy and dense sampling of metastases combined with extensive multiomic profiling, our study elucidates the many mechanisms that melanomas use to evade treatment and the immune system, whether through mutations, widespread copy-number alterations, or extrachromosomal DNA. See related commentary by Shain, p. 1294. This article is highlighted in the In This Issue feature, p. 1275., (©2023 The Authors; Published by the American Association for Cancer Research.)

Patients with blood cancer continue to have a greater risk of inadequate immune responses following three COVID-19 vaccine doses and risk of severe COVID-19 disease. In the context of the CAPTURE study (NCT03226886), we report immune responses in 80 patients with blood cancer who received a fourth dose of BNT162b2. We measured neutralizing antibody titers (NAbTs) using a live virus microneutralization assay against wild-type (WT), Delta, and Omicron BA.1 and BA.2 and T cell responses against WT and Omicron BA.1 using an activation-induced marker (AIM) assay. The proportion of patients with detectable NAb titers and T cell responses after the fourth vaccine dose increased compared with that after the third vaccine dose. Patients who received B cell-depleting therapies within the 12 months before vaccination have the greatest risk of not having detectable NAbT. In addition, we report immune responses in 57 patients with breakthrough infections after vaccination., Competing Interests: Declaration of interests The authors declare no competing interest., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Patients with cancer have higher COVID-19 morbidity and mortality. Here we present the prospective CAPTURE study, integrating longitudinal immune profiling with clinical annotation. Of 357 patients with cancer, 118 were SARS-CoV-2 positive, 94 were symptomatic and 2 died of COVID-19. In this cohort, 83% patients had S1-reactive antibodies and 82% had neutralizing antibodies against wild type SARS-CoV-2, whereas neutralizing antibody titers against the Alpha, Beta and Delta variants were substantially reduced. S1-reactive antibody levels decreased in 13% of patients, whereas neutralizing antibody titers remained stable for up to 329 days. Patients also had detectable SARS-CoV-2-specific T cells and CD4 + responses correlating with S1-reactive antibody levels, although patients with hematological malignancies had impaired immune responses that were disease and treatment specific, but presented compensatory cellular responses, further supported by clinical recovery in all but one patient. Overall, these findings advance the understanding of the nature and duration of the immune response to SARS-CoV-2 in patients with cancer., (© 2021. The Author(s).)

Coronavirus disease 2019 (COVID-19) antiviral response in a pan-tumor immune monitoring (CAPTURE) ( NCT03226886 ) is a prospective cohort study of COVID-19 immunity in patients with cancer. Here we evaluated 585 patients following administration of two doses of BNT162b2 or AZD1222 vaccines, administered 12 weeks apart. Seroconversion rates after two doses were 85% and 59% in patients with solid and hematological malignancies, respectively. A lower proportion of patients had detectable titers of neutralizing antibodies (NAbT) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOC) versus wild-type (WT) SARS-CoV-2. Patients with hematological malignancies were more likely to have undetectable NAbT and had lower median NAbT than those with solid cancers against both SARS-CoV-2 WT and VOC. By comparison with individuals without cancer, patients with hematological, but not solid, malignancies had reduced neutralizing antibody (NAb) responses. Seroconversion showed poor concordance with NAbT against VOC. Previous SARS-CoV-2 infection boosted the NAb response including against VOC, and anti-CD20 treatment was associated with undetectable NAbT. Vaccine-induced T cell responses were detected in 80% of patients and were comparable between vaccines or cancer types. Our results have implications for the management of patients with cancer during the ongoing COVID-19 pandemic., (© 2021. The Author(s).)

Owing to spatial segregation of tumor subclones, solid tumor sampling using formalin-fixed, paraffin-embedded blocks is often inadequate to represent the genomic heterogeneity of solid tumors. We present an approach, representative sampling, to dissect and homogenize leftover residual surgical tissue prior to sequencing. We also detail optional tumor cell enrichment and DNA preparation. This method, applicable only to surgically removed tumors with leftover tissue, facilitates robust sampling to avoid missing or over-representing actionable variants. For complete details on the use and execution of this protocol, please refer to Litchfield et al. (2020)., Competing Interests: L.L.G., S.S., S.M.H., C.J., A.B., and N.R.A. are employees of Roche Diagnostics. L.L.G., S.S., and N.R.A. are shareholders of Roche. Funding was provided by 10.13039/100004337Roche. Roche has submitted patent applications for methods, workflows, and applications downstream of representative sampling. S.T. has received speaking fees from Roche, AstraZeneca, Novartis, and Ipsen. S.T. has the following patents filed: Indel mutations as a therapeutic target and predictive biomarker PCTGB2018/051892 and PCTGB2018/051893 and Clear Cell Renal Cell Carcinoma Biomarkers P113326GB., (© 2021 The Authors.)

A diverse range of clinical phenotypes are observed in clear-cell renal cell carcinoma (ccRCC) with resultant therapeutic implications. Molecular characterisation underpinning the diversity observed has been qualified, where the near ubiquitous loss of the short arm of chromosome 3 precedes distinct evolutionary trajectories involving different sequences and combinations of genetic events. Primary tumours are characterised by varying degrees of intratumoural heterogeneity and chromosomal complexity associated with distinct metastatic phenotypes. An evolutionary understanding reconciles the diverse clinical phenotypes observed in metastatic ccRCC and has the potential to impact patient management. PATIENT SUMMARY: Re-tracing the evolutionary paths taken by clear-cell kidney cancer through analyses at the gene level gives an insight into genetic changes that are correlated to metastatic potential. This may provide a framework to guide therapeutic interventions, especially in identifying candidates for surgical intervention., (Crown Copyright © 2020. Published by Elsevier B.V. All rights reserved.)

Indications for immune checkpoint inhibitor therapy are increasing. As the population ages, many patients receiving such drugs will be older adults. Such patients are under-represented in clinical trials, and therefore the safety of immune checkpoint inhibitors in this population has not been adequately assessed. A retrospective multicenter analysis of toxicities was performed in patients with advanced or metastatic solid cancers receiving anti-programmed cell death protein 1 (anti-PD-1) and/or anti-CTLA4 antibodies across three age cohorts (<65 years, 65-74 years and ≥75 years) using univariable and multivariable analyzes. Eligible patients (n=448) were divided into age cohorts: <65 years (n=185), 65-74 years (n=154) and ≥75 years (n=109). Fewer patients in the oldest cohort (7.3%) received an anti-CTLA4 antibody containing regimen compared with the younger cohorts (21.1% and 17.5%). There was no significant difference overall in all grade or ≥G3 toxicities between age cohorts. Significantly fewer patients in the older (65-74 years and ≥75 years) age cohorts discontinued treatment because of toxicity (10.1% and 7.4%) compared with in the <65 years cohort (20.5%; p=0.006). Using logistic regression, only treatment type (ipilimumab containing) was significantly associated with all grade toxicity. However, there was a significantly lower incidence of all-grade endocrine toxicity in the oldest cohort (11.0%) compared with the youngest cohort (22.7%, p=0.02; OR 0.43, 95% CI 0.21 to 0.87), while all-grade dermatological toxicity showed the reverse trend (28.4% vs 18.9%; OR 1.85, 95% CI 1.04 to 3.30). Results were corroborated in the sensitivity analysis using only data from patients who received PD-1 inhibitor monotherapy. This multicenter, real-world cohort demonstrates that immune checkpoint inhibitor therapy is safe and well tolerated regardless of age, with no appreciable increase in adverse events in older adult patients., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)

Background: In light of the coronavirus disease 2019 (COVID-19) pandemic, cancer centres in the United Kingdom and Europe re-organised their services at an unprecedented pace, and many patients with cancer have had their treatments severely disrupted. Patients with cancer were considered at high risk on sparse evidence, and despite a small number of emerging observational studies, the true incidence and impact of COVID-19 in the 'at-risk' population of patients with cancer is yet to be defined., Methods: Epidemiological and clinical data were collected prospectively for patients attending the Royal Marsden Hospital and three network hospitals between March 1st and April 30th 2020 that were confirmed to have Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection. Significance of clinical and pathological characteristics was assessed using the Fisher's exact test and Wilcoxon rank sum test, whilst univariate and multivariate logistic regression models were used to further assess risk. The number of patients attending in March/April 2020 for face-to-face attendances was also extracted., Findings: During the 2-month study period, 867 of 13,489 (6.4%) patients met the criteria leading to swab testing. Of the total at-risk population, only 113 of 13,489 (0.84%) were swab positive, 101 of 13,489 (0.75%) required hospital admission and 29 of 13,489 (0.21%) died of COVID-19. Of the patients that attended the hospital to receive cytotoxic chemotherapy alone or in combination with other therapy, 59 of 2001 (2.9%) were admitted to the hospital for COVID-19-related issues and 20 of 2001 (1%) died. Of the patients that collected targeted treatments, 16 of 1126 (1.4%) were admitted and 1 of 1126 (0.1%) died. Of the 11 patients that had received radiotherapy, 6 of 1042 (0.6%) required inpatient admission and 2 of 1042 (0.2%) died., Interpretations: Administration of systemic anticancer therapy appears to be associated with a modest risk of severe COVID-19 infection. Based on this snapshot taken as the first wave of COVID-19 hit our practice, we conclude that continuation of active cancer treatment, even in the palliative setting, is appropriate., Competing Interests: Conflict of interest statement R.J. reports receiving grants/research support from MSD and GSK and consultation fees from Adaptimmune, Athenex, Blueprint, Clinigen, Eisai, Epizyme, Daichii, Deciphera, Immunedesign, Lilly, Merck, Pharmamar and UptoDate, outside the submitted work. S.S. reports receiving grants and personal fees from Roche, outside the submitted work. All other authors declare no competing interests., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Although thousands of solid tumors have been sequenced to date, a fundamental under-sampling bias is inherent in current methodologies. This is caused by a tissue sample input of fixed dimensions (e.g., 6 mm biopsy), which becomes grossly under-powered as tumor volume scales. Here, we demonstrate representative sequencing (Rep-Seq) as a new method to achieve unbiased tumor tissue sampling. Rep-Seq uses fixed residual tumor material, which is homogenized and subjected to next-generation sequencing. Analysis of intratumor tumor mutation burden (TMB) variability shows a high level of misclassification using current single-biopsy methods, with 20% of lung and 52% of bladder tumors having at least one biopsy with high TMB but low clonal TMB overall. Misclassification rates by contrast are reduced to 2% (lung) and 4% (bladder) when a more representative sampling methodology is used. Rep-Seq offers an improved sampling protocol for tumor profiling, with significant potential for improved clinical utility and more accurate deconvolution of clonal structure., Competing Interests: Declaration of Interests S.T. reports grants from Roche Tissue Diagnostics. K.L., S.T., and C.S. report speaker fees from Roche Tissue Diagnostics. K.L., S.S., S.T., and N.R.A. report a patent pending using Rep-Seq profiling to support detection of MRD. N.R.A., S.S., L.G., A.B., K.F.L., and S.H. have patents pending on representative sampling of solid tumors. C.S. receives grant support from Pfizer, AstraZeneca (AZ), Bristol-Myers Squibb (BMS), Roche-Ventana, Boehringer Ingelheim, and Ono. C.S. has consulted for Pfizer, Novartis, GlaxoSmithKline (GSK), Merck Sharpe & Dohme (MSD), BMS, Celgene, AZ, Illumina, Genentech, Roche-Ventana, GRAIL, Medicxi, and the Sarah Cannon Research Institute. C.S. is a shareholder of Apogen Biotechnologies, Epic Bioscience, and GRAIL and has stock options in and is co-founder of Achilles Therapeutics. Outside of the submitted work, K.L., S.T., and C.S. have a patent pending on indel burden and CPI response and a patent pending on targeting of frameshift neoantigens for personalized immunotherapy. J.L. reports institutional research support from BMS, MSD, Novartis, Pfizer, Achilles Therapeutics, Roche, Nektar Therapeutics, Covance, Immunocore, Pharmacyclics, and Aveo and consultancy support from Achilles, AZ, Boston Biomedical, BMS, Eisai, EUSA Pharma, GSK, Ipsen, Imugene, Incyte, iOnctura, Kymab, Merck Serono, MSD, Nektar, Novartis, Pierre Fabre, Pfizer, Roche/Genentech, Secarna, and Vitaccess. S.T. has received speaking fees from Astra Zeneca, Novartis, and Ipsen. S.T., K.L., and C.S. have the following patents filed: Clear Cell Renal Cell Carcinoma BiomarkersP113326GB., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Neurological adverse events from immune checkpoint inhibition are increasingly recognised, especially with combination anti-cytotoxic T-lymphocyte antigen 4 (CTLA4) and anti-programmed death receptor 1 (anti-PD-1) therapies. Their presenting symptoms and signs are often subacute and highly variable, reflecting the numerous components of the nervous system. Given the risk of substantial morbidity and mortality, it is important to inform patients of symptoms that may be of concern, and to assess any suspected toxicity promptly. As with other immune-related adverse events, the cornerstone of management is administration of corticosteroids. Specialist neurology input is vital in this group of patients to guide appropriate investigations and tailor treatment strategies., Competing Interests: Competing interests: ST acknowledges research funding and speaker fees from Ventana Medical Systems and consulting fees from Novartis. JL acknowledges institutional research support from: BMS, MSD, Novartis, Pfizer, Achilles Therapeutics, Roche, Nektar Therapeutics, Covance, Immunocore, Pharmacyclics, Aveo and consultancy fees from Achilles Therapeutics, AZ, Boston Biomedical, BMS, Eisai, EUSA Pharma, GSK, Ipsen, Imugene, Incyte, iOnctura, Kymab, Merck Serono, MSD, Nektar, Novartis, Pierre Fabre, Pfizer, Roche/Genentech, Secarna, Vitaccess, as well as support from NIHR RM/ICR Biomedical Research Centre for cancer.

Limited medication adherence and persistence with treatment are barriers to successful management of type 2 diabetes (T2D). We searched MEDLINE, EMBASE, the Cochrane Library, the Register of Controlled Trials, PsychINFO and CINAHL for observational and interventional studies that compared the adherence or persistence associated with 2 or more glucose-lowering medications in people with T2D. Where 5 or more studies provided the same comparison, a random-effects meta-analysis was performed, reporting mean difference (MD) or odds ratio (OR) for adherence or persistence, depending on the pooled study outcomes. We included a total of 48 studies. Compared with metformin, adherence (%) was better for sulphonylureas (5 studies; MD 10.6%, 95% confidence interval [CI] 6.5-14.7) and thiazolidinediones (TZDs; 6 studies; MD 11.3%, 95% CI 2.7%-20.0%). Adherence to TZDs was marginally better than adherence to sulphonylureas (5 studies; MD 1.5%, 95% CI 0.1-2.9). Dipeptidyl peptidase-4 inhibitors had better adherence than sulphonylureas and TZDs. Glucagon-like peptide-1 receptor agonists had higher rates of discontinuation than long-acting analogue insulins (6 studies; OR 1.95; 95% CI 1.17-3.27). Long-acting insulin analogues had better persistence than human insulins (5 studies; MD 43.1 days; 95% CI 22.0-64.2). The methods used to define adherence and persistence were highly variable., (© 2017 John Wiley & Sons Ltd.)

Background: Ethnicity recording within primary care computerised medical record (CMR) systems is suboptimal, exacerbated by tangled taxonomies within current coding systems.Objective To develop a method for extending ethnicity identification using routinely collected data., Methods: We used an ontological method to maximise the reliability and prevalence of ethnicity information in the Royal College of General Practitioner's Research and Surveillance database. Clinical codes were either directly mapped to ethnicity group or utilised as proxy markers (such as language spoken) from which ethnicity could be inferred. We compared the performance of our method with the recording rates that would be identified by code lists utilised by the UK pay for the performance system, with the help of the Quality and Outcomes Framework (QOF)., Results: Data from 2,059,453 patients across 110 practices were included. The overall categorisable ethnicity using QOF codes was 36.26% (95% confidence interval (CI): 36.20%-36.33%). This rose to 48.57% (CI:48.50%-48.64%) using the described ethnicity mapping process. Mapping increased across all ethnic groups. The largest increase was seen in the white ethnicity category (30.61%; CI: 30.55%-30.67% to 40.24%; CI: 40.17%-40.30%). The highest relative increase was in the ethnic group categorised as the other (0.04%; CI: 0.03%-0.04% to 0.92%; CI: 0.91%-0.93%)., Conclusions: This mapping method substantially increases the prevalence of known ethnicity in CMR data and may aid future epidemiological research based on routine data.

Introduction: Treatment options for type 2 diabetes are becoming increasingly complex with people often prescribed multiple medications, and may include both oral and injectable therapies. There is ongoing debate about which drug classes provide the optimum second-line and third-line treatment options. In the real world, patient adherence and persistence determines medication effectiveness. A better understanding of adherence may help inform the choice of second-line and third-line drug classes., Methods and Analysis: This systematic review will compare adherence and persistence rates across the different classes of medication available to people with type 2 diabetes. It will include all identified studies comparing medication adherence or persistence between two or more glucose-lowering medications in people with type 2 diabetes. Research databases (MEDLINE, EMBASE, The Cochrane Library, The Register of Controlled Trials, PsychINFO and CINAHL) will be searched for relevant articles, using a comprehensive search strategy. All identified medication trials and observational studies will be included which compare adherence or persistence across classes of diabetes medication. The characteristics and outcomes of all the included studies will be reported along with a study quality grade, assessed using the Cochrane Risk Assessment Tool. The quality of adjustment for confounders of adherence or persistence will be reported for each study. Where multiple (n ≥ 3) studies provide compare adherence or persistence across the same 2 medication classes, a meta-analysis will be performed., Ethics and Dissemination: No ethics approval is required. This review and meta-analysis (where possible) will provide important information on the relative patient adherence and persistence, with the different classes of diabetes therapies. Once complete, the results will be made available by peer-reviewed publication., Trial Registration Number: CRD42015027865., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)