A combined analysis of two prospective randomised studies exploring the impact of extended post-radiation temozolomide on survival outcomes in newly diagnosed glioblastoma

PURPOSE

The optimal duration of post-radiation temozolomide in newly diagnosed glioblastoma remains unclear, with no published phase III randomised trials. Standard-of-care stipulates 6 months. However, in routine care, it is often extended to 12 months, despite lacking robust supporting data.

METHODS

GEINO14-01 (Spain) and EX-TEM (Australia) studies enrolled glioblastoma patients without progression at the end of 6 months post-radiation temozolomide. Participants were randomised 1:1 to six additional months of temozolomide or observation. Primary endpoint was 6-month progression free survival from date of randomisation (6mPFS). Secondary endpoints included overall survival (OS) and toxicity. 204 patients were required to detect an improvement in 6mPFS from 50 to 60% (80% power). Neither study recruited sufficient patients. We performed a combined analysis of individual patient data.

RESULTS

205 patients were recruited: 159 in GEINO14-01 (2014-2018) and 46 in EX-TEM (2019-2022). Median follow-up was 20.0 and 14.5 months. Baseline characteristics were balanced. There was no significant improvement in 6mPFS (57.2% vs 64.0%, OR0.75, p = 0.4), nor across any subgroups, including MGMT methylated; PFS (HR0.92, p = 0.59, median 7.8 vs 9.7 months); or OS (HR1.03, p = 0.87, median 20.1 vs 19.4 months). During treatment extension, 64% experienced any grade adverse event, mainly fatigue and gastrointestinal (both 54%). Only a minority required treatment changes: 4.5% dose delay, 7.5% dose reduction, 1.5% temozolomide discontinuation.

CONCLUSION

For glioblastoma patients, extending post-radiation temozolomide from 6 to 12 months is well tolerated but does not improve 6mPFS. We could not identify any subset that benefitted from extended treatment. Six months should remain standard-of-care.

Comparative genomic analysis of Fischer F344 rat livers exposed for 90 days to 3-methylfuran or its parental compound furan

Furan is a naturally forming compound found in heat-processed foods such as coffee, canned meats, and jarred baby food. It is concurrently found with analogues including 2-methylfuran (2-MF) and 3-methylfuran (3-MF), and toxicity studies demonstrate all are potent liver toxins. Toxicity studies found 3-MF is more toxic than either furan, or 2-MF. The present analysis assesses the transcriptional response in liver samples taken from male Fischer (F344) rats exposed to furan or 3-MF from 0 to 2.0 and 0-1.0 mg/kg bw/day, respectively, for 90 days. Transcriptional analyses found decreased liver function and fatty acid metabolism are common responses to both furan and 3-MF exposure. Furan liver injury promotes a ductular reaction through Hippo and TGFB signalling, which combined with increased immune response results in ameliorating perturbed bile acid homeostasis in treated rats. Failure to activate these pathways in 3-MF exposed rats and decreased p53 activity leads to cholestasis, and increased toxicity. Finally, BMD analysis indicate many of the most sensitive pathways affected by furan and 3-MF exposure relate to metabolism - malate dehydrogenase and glucose metabolism with BMDLs of 0.03 and 0.01 mg/kg bw/day for furan and 3-MF exposure, respectively, which agrees with BMDLs previously reported for apical and microarray data.

A resonant sextuplet of sub-Neptunes transiting the bright star HD 110067

Planets with radii between that of the Earth and Neptune (hereafter referred to as 'sub-Neptunes') are found in close-in orbits around more than half of all Sun-like stars1,2. However, their composition, formation and evolution remain poorly understood3. The study of multiplanetary systems offers an opportunity to investigate the outcomes of planet formation and evolution while controlling for initial conditions and environment. Those in resonance (with their orbital periods related by a ratio of small integers) are particularly valuable because they imply a system architecture practically unchanged since its birth. Here we present the observations of six transiting planets around the bright nearby star HD 110067. We find that the planets follow a chain of resonant orbits. A dynamical study of the innermost planet triplet allowed the prediction and later confirmation of the orbits of the rest of the planets in the system. The six planets are found to be sub-Neptunes with radii ranging from 1.94R⊕ to 2.85R⊕. Three of the planets have measured masses, yielding low bulk densities that suggest the presence of large hydrogen-dominated atmospheres.

The management of hepatocellular carcinoma. Current expert opinion and recommendations derived from the 24th ESMO/World Congress on Gastrointestinal Cancer, Barcelona, 2022

This article summarises expert discussion on the management of patients with hepatocellular carcinoma (HCC), which took place during the 24th World Gastrointestinal Cancer Congress (WGICC) in Barcelona, July 2022. A multidisciplinary approach is mandatory to ensure an optimal diagnosis and staging of HCC, planning of curative and therapeutic options, including surgical, embolisation, ablative strategies, or systemic therapy. Furthermore, in many patients with HCC, underlying liver cirrhosis represents a challenge and influences the therapeutic options.

A49 TWO NOVEL LIVE BIOTHERAPEUTIC PRODUCTS PROTECT DSS-EXPOSED MICE FROM ACUTE COLITIS WHEN COMPARED TO 5-ASA

Background

Live biotherapeutic products (LBPs) offer a more rationalized and multitargeted approach to treating gastrointestinal diseases. BioColoniz and BioPersist are two LBPs derived from the parental strains L. reuteri and E. coli Nissle 1917 (EcN), respectively. The parental strains are known to offer some benefit in preventing relapses in IBD patients however the results are heterogeneous. To overcome this, the parental strains were approached as LBPs by introducing traits to thrive under the inflammatory conditions of the colon. Therefore, our aim is to characterize the role of these LBPs in IBD.

Purpose

To evaluate the therapeutic effect of the LBPs BioColoniz and BioPersist in an acute model of colitis.

Method

Female C57Bl/6 mice were treated with BioColoniz or BioPersist via oral gavage for three consecutive days prior to DSS challenge. Then mice were exposed to 3.5% DSS via drinking water for seven days. As controls, we also included mice treated with vehicle or the parental strains L. reuteri or EcN. In order to compare the effect of LBPs in the onset of acute colitis to current maintenance therapies for UC, we also exposed another group of mice to DSS and simultaneously administer 5-ASA. Mice were monitored daily for signs of disease and at the end of the experiment, colon tissue was collected for histopathological and molecular analysis.

Result(s)

The administration of BioColoniz and BioPersist delayed and decreased the colitic phenotype of mice exposed to DSS. Differences in signs of disease, such as diarrhea and weight loss, were evident by day 4 for vehicle or 5-ASA groups, whereas mice in the LBPs groups were still gaining weight. When analyzing the histopathological changes, mice in the LBPs groups presented lower scores when compared to the vehicle and 5-ASA groups. Specifically, mice treated early with BioColoniz or BioPersist presented a more preserved mucosal architecture with visible crypts. Although 5-ASA-treated mice still had vestiges of crypts, the damage in the mucosal architecture was more severe, similar to the observed in mice treated with the parental strains EcN and L. reuteri. We also looked at the expression of proinflammatory cytokines, finding an increase in TNFα, IFNγ, and IL-17a in mice treated with 5-ASA but not in mice treated with LBPs. However, the expression of protective factors such as mucin Muc2 or the antimicrobial peptide Reg3γ was similarly high in 5-ASA and LBP-treated mice when compared to vehicle or parental strains groups, suggesting some therapeutic commonalities between 5-ASA and our LBPs.

Conclusion(s)

The early administration of the LBPs BioColoniz and BioPersist protect mice from severe acute colitis, being more protective than 5-ASA. Since some differences and similarities were observed between the LBPs- and 5-ASA-treated mice, such as crypt preservation versus increased expression of some protective factors, the next step will aim to identify which mechanisms are specifically triggered by the LBPs.

Disclosure of Interest

None Declared

Qualitative examination of collaboration in team-based primary care during the COVID-19 pandemic

OBJECTIVE

The objective of this study was to describe Ontario primary care teams' experiences with collaboration during the COVID-19 pandemic. Descriptive qualitative methods using focus groups conducted virtually for data collection.

SETTING

Primary care teams located in Ontario, Canada.

PARTICIPANTS

Our study conducted 11 focus groups with 10 primary care teams, with a total of 48 participants reflecting a diverse range of interprofessional healthcare providers and administrators working in primary care.

RESULTS

Three themes were identified using thematic analysis: (1) prepandemic team functioning facilitated adaptation, (2) new processes of team interactions and collaboration, and (3) team as a foundation of support.

CONCLUSIONS

Results revealed the importance of collaboration for provider well-being, and the challenges of providing collaborative team-based primary care in the pandemic context. Caution against converting primary care collaboration to predominantly virtual modalities postpandemic is recommended. Further research on team functioning during the COVID-19 pandemic in other healthcare organisations will offer additional insight regarding how primary care teams can work collaboratively in a postpandemic environment.

The experience of primary care teams during the early phase of COVID-19: A qualitative study of primary care practice leaders in Ontario, Canada

BACKGROUND

The COVID-19 pandemic has caused a rapid shift to virtual care in primary care practices around the globe. There has been little focus on the experiences of interprofessional teams through the lens of primary care practice leaders. The objective of this study was to examine the experience of primary care teams during the first wave of the COVID-19 pandemic from the perspective of primary care leadership.

METHODS

Qualitative study using qualitative description methods. Executive Directors of interprofessional primary care teams belonging to the Association of Family Health Teams of Ontario (AFHTO) were invited to participate. Executive Directors were interviewed and the interview transcripts were analyzed using thematic analysis.

RESULTS

Seventy-one Executive Directors from across all regions of Ontario were interviewed for the study, representing 37% of the AFHTO member clinics. Four themes were identified in the data: i) Complexities of Virtual Care, ii) Continuation of In-person Care, iii) Supporting Patients at Risk, and iv) Stepping up and into New Roles.

CONCLUSIONS

Primary care teams rapidly mobilized to deliver the majority of their care virtually, while continuing to provide in-person and home care as required. Major challenges to virtual care included technological infrastructure and unfamiliarity with virtual platforms. Advantages to virtual care included convenience and time savings. Virtual care will likely continue to be an important mode of primary care delivery moving forward.

Long-term impact of persistent vegetations at 6 month followup after treatment of infective endocarditis: a substudy of the Partial Oral vs Intravenous Antibiotic Treatment of Endocarditis (POET) tria

Background

Our knowledge of changes in vegetation size throughout the course of infective endocarditis (IE) and the impact of persistent vegetations on mortality or embolization after completed antibiotic treatment is sparse. No study has previously investigated the prevalence or clinical impact of persistent vegetations on transthoracic echocardiography (TTE) at 6-months follow-up after ended IE treatment.

Purpose

To investigate the association between persistent vegetations at the 6-months TTE after treatment for IE and long-term prognosis as assessed in the POET trial.

Methods

The POET trial was a nationwide, multicenter RCT, randomizing 400 patients to either partial oral or intravenous (IV) antibiotic treatment of left-sided IE, after initial stabilization of infection using conventional IV therapy.

A persistent vegetation was defined as a vegetation seen on 6-months follow-up TTE (4–7 months) after ended antibiotic treatment for IE. In the POET trial, primary outcome was defined as 1) all-cause mortality, 2) unplanned cardiac surgery, 3) embolic events or 4) relapse of bacteremia, in the 5-year follow-up period. Patients without TTE due to death or lack of available TTE were excluded.

Results

Out of 400 patients, 20 were excluded due to death during 6-months follow-up, and 201 were excluded due to unavailable TTE, leaving 179 TTEs for analysis.

At 6-months follow-up, a persistent vegetation was seen in 30 patients (16.7%, 21 males (70%), mean age 69.6 years (SD 7.7)) (Table 1). Seventeen patients (56.7%) had a persistent vegetation on the aortic valve and 13 patients (43.3%) on the mitral valve. More patients without a persistent vegetation had undergone initial surgical treatment of IE than those with a vegetation (57.7 vs 23.3%, p=0.001). In all surgically treated patients with persistent vegetation at 6-months follow-up, the vegetation was found on another valve than the operated valve.

The composite primary outcome from 6-months follow-up and until 5-year follow-up occurred in 8 patients (26.7%) with a persistent vegetation, compared to 38 patients (25.5%) (p=1.00) without. (Table 2) In patients randomized for peroral treatment, no significant difference in prevalence of persistent vegetation was found (15 patients (50%) with persistent vegetations vs. 74 patients (49.7%) without, p=1.00).

Conclusion

The occurrence of persistent vegetations at 6 months follow-up was 16.7%. There was no association between persistent vegetations at 6-months follow-up and the occurrence of the primary outcome after 5 years follow-up, suggesting that the risk associated with residual vegetations after end of antibiotic treatment is negligible after 6-months.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): The Danish Heart Foundation

Sex-related differences in sternocleidomastoid muscle morphology in healthy young adults: A cross-sectional magnetic resonance imaging measurement study

BACKGROUND

Changes in sternocleidomastoid (SCM) muscle cross-sectional area (CSA) and volume may contribute to neck-related concussion symptoms and whiplash-associated disorders. Magnetic resonance imaging (MRI) data on healthy SCM morphology can provide information that may lead to targeted treatment protocols.

OBJECTIVES

To examine sex-related differences in MRI-based SCM CSA, SCM volume and neck area in healthy young adults, to analyze associations between measurements and participant variables and to assess inter-rater reliability for measurement quantification.

DESIGN

Cross-sectional study.

METHODS

13 males and 14 females underwent MRI scans. Slices obtained from C3-C7 were analyzed by three raters. SCM CSA at C4, total SCM volume from C3-C7 and neck area at C4 were quantified. Measurements were calculated as absolute and normalized values by body mass. Multivariable regression was used to analyze associations between normalized measurement values and participant variables. Inter-rater reliability was determined using intraclass correlation coefficients (ICC).

RESULTS

Females had significantly lower normalized overall average SCM CSA (mean difference 1.3 mm²/kg (95% CI 0.4-2.2, p = 0.006) and total SCM volume (mean difference 140.8 mm3/kg (95% CI 66.1-215.5, p < 0.001) than males. Regression models indicated female sex was associated with lower normalized overall average SCM CSA (p = 0.004) and total SCM volume (p < 0.001). Inter-rater reliability was excellent for SCM CSA (ICC_3,3 = 0.909), SCM volume (ICC_3,3 = 0.910) and neck area (ICC_3,3 = 0.995).

CONCLUSIONS

These results enhance our understanding of sex-related differences in SCM morphology and will inform future research and clinical practice related to cervical muscle injury.

Changing Parental Knowledge and Treatment Acceptance for ADHD: A Pilot Study

This pilot study assessed the feasibility and potential effectiveness of a single-session workshop in modifying parental beliefs/knowledge about attention-deficit/hyperactivity disorder (ADHD) in children and impact on treatment acceptance/utilization. Concerns raised by school professionals about lack of treatment follow-through after ADHD diagnosis and parental misinformation about medication usage catalyzed this project. A single-group pre-post quasi-experimental design was used. Sixty-eight parents completed ADHD knowledge/belief scales and stress inventories, and pre-ADHD and post-ADHD information workshop. Follow-up calls were made after the workshop to assess treatment utilization. Parents/caregivers experienced significant knowledge and belief changes regarding medication efficacy, willingness to accept physician treatment recommendations, and rejection of non-empirically based treatments. Follow-up data showed that 41% of contacted participants met with physicians to discuss medication utilization and behavioral treatments. Brief, one-session psycho-educational workshops were feasible and impacted parental beliefs and behaviors regarding scientifically supported interventions for ADHD.

The impact of cultural stress and gender norms on alcohol use severity among Latino immigrant men

Alcohol misuse affects 15 million people in the United States. Compared to White men, Latino men have disproportionately higher rates of both alcohol misuse and negative alcohol-related consequences (e.g. drunk driving, liver disease, alcohol dependence, HIV/AIDS). This cross sectional study examined how cultural stressors [immigration stress and negative context of reception (NCR)] coupled with traditional Latino male gender norms (machismo and caballerismo) influences alcohol use severity (AUS) among adult Latino immigrant men. Data for the present study was collected between 2017 and 2018 from 279 Cuban, Central American, and South American adult Latino men who immigrated to the US approximately 10 years prior. Results from hierarchical multiple regression analysis revealed higher levels of perceived NCR (β = 0.15, p  = .01), and machismo (β = 0.16, p = .02) were associated with greater AUS. Significant interaction effects were found between both cultural stressors and machismo [immigration stress x machismo (β = 0.22, p < .001); NCR x machismo (β = 0.22, p < .001)] whereby higher levels of machismo strengthened the association between cultural stress and AUS. Findings from the present study can inform culturally appropriate interventions aimed at mitigating alcohol use among Latino immigrant men.

Recommendations for virtual care in primary care practices: a survey of patients across Ontario, Canada

Context: The onset of COVID-19 has required the rapid adoption of virtual services in primary care (PC) practices, and virtual care delivery is likely to continue to some extent post-pandemic. Objective: To understand patient experience with synchronous virtual (telephone (Tel)/Video) appointments and elicit recommendations for its future use. Design: Mixed method, including patient survey co-developed with stakeholders and implemented online Feb-Mar 2021 with large promotional efforts through social media, patient and caregiver organizations, and other networks. We report on the survey results. Eligibility: 1+ virtual encounter in PC. Outcome measures: A) Patient experience scale (12/17 questions for Tel/Video) covering 4 sub-dimensions; B) Access related questions. Questions had 5-point Likert scale items (strongly disagree (-2) to strongly agree (+2)) and were converted into percentage (potential range -100%, +100%) Setting : Ontario, Canada which offers universal coverage for PC visits with no co-payment. Results: 534 eligible respondents (402/18/114 had Tel/Video/both): Females (78%), < 55 years (61%), white (75%), employed (61%), bachelor's degree (74%), family income > 100k (52%). Encounters evaluated were with family physicians (vs other health professionals) for 75%/46% of Tel/Video encounters. A) Patient Experience (Tel/Video) overall score: 75%/78%; Sub-dimensions: technology: 92%/84%, patient-provider relationship: 83%/86%, quality of care: 66%/66%, whole-person care: 43%/53%. Factors associated with a statistically significant(*) > 10% higher overall score in tel and/or video were: non-females: (8%*/14%*), French speaking (13%*/16%*), patient-provider relationship >1 year (16%*/7%), provider age < 50 (5%/15%*), having the choice of appointment time (15%*/21%*). Wanting to show problem to the provider was associated with a lower scores (-23%*/NA). B) Access Respondents overwhelmingly reported that Tel/Video visits reduced time (97%/97%), costs (81%/85%), and was more convenient (91%/91%). The majority wanted Tel (69%) and Video (71%) visits at least as often as in person visits post-covid. Only 5% did not want any future virtual care. Conclusions: Patient experience was largely positive and is influenced by patient/provider factors. Patients and providers may benefit from support/training to optimize care experience. We are now evaluating whether the reasons for visits influences care experience.

Early life environmental exposures have a minor impact on the gut ecosystem following a natural birth

A growing body of evidence suggests that the environment is an important source of colonizing bacteria for the gastrointestinal tract of C-section delivered infants, who undergo multiple birth-related interventions; however, the extent to which environmental microbes impact vaginally delivered infants remains unclear. Here we investigated the impact of rural and urban environmental exposures on microbial establishment and immunity in vaginally delivered mice. We simulated rural and urban home environments by adding soil types to cages from breeding to weaning. Our aims were to determine the impact of rural and urban soil exposures on the gut microbiome in young mice and to understand whether these changes persisted into adulthood. Host immune cytokines and microbial short-chain fatty acids were quantified to understand the impact on immunity. We found that early-life soil exposure had a minor effect on the richness of the neonatal gut microbiota contributing 5% and 9% variation in the bacterial community structure between mice during early-life and adulthood, respectively. Exposure to urban soil increased Clostridiaceae and propionic acid which persisted into adulthood. While soil exposure had a limited effect on the gut taxa, systemic cytokine and chemokine profiles were altered in adulthood. The findings presented here show that unlike in C-section deliveries previously reported, environmental exposures following a natural birth have a limited impact on the gut microbial taxa but potentially play an important role in immune-mediated disease susceptibility later in life.

The Delivery of Patient Care in Ontario's Family Health Teams during the First Wave of the COVID-19 Pandemic

OBJECTIVE

The objective of this paper was to identify continuations and changes in care delivery methods in primary care teams during the COVID-19 pandemic.

DESIGN

The study used a cross-sectional, web-based survey comprising close-ended and open-ended questions.

SETTING

The setting comprised family health teams (FHTs) across Ontario, Canada.

PARTICIPANTS

The participants included executive directors of FHTs or designates of their choosing.

SURVEY

Descriptive statistics were derived from responses to close-ended questions, and responses to open-ended questions were coded using thematic analysis.

RESULTS

With 93 participants, the response rate was 48%. Participants reported the continuation of in-person care, the implementation of virtual care across FHTs and collaboration within these teams and their communities.

Bone infection: a clinical priority for clinicians, scientists and educators

Bone infection has received increasing attention in recent years as one of the main outstanding clinical problems in orthopaedic-trauma surgery that has not been successfully addressed. In fact, infection may develop across a spectrum of patient types regardless of the level of perioperative management, including antibiotic prophylaxis. Some of the main unknown factors that may be involved, and the main targets for future intervention, include more accurate and less invasive diagnostic options, more thorough and accurate debridement protocols, and more potent and targeted antimicrobials. The underlying biology dominates the clinical management of bone infections, with features such as biofilm formation, osteolysis and vascularisation being particularly influential. Based on the persistence of this problem, an improved understanding of the basic biology is deemed necessary to enable innovation in the field. Furthermore, from the clinical side, better evidence, documentation and outreach will be required to translate these innovations to the patient. This review presents the findings and progress of the AO Trauma Clinical Priority Program on the topic of bone infection.

Phenotypic presentation trends of transthyretin amyloid cardiomyopathy: are we getting better?

Introduction

Transthyretin amyloid cardiomyopathy (ATTR-CM) is being increasingly recognized due to recent advances in non-invasive imaging notably bone scintigraphy and newer effective therapies - particularly tafamidis, which was shown to improve survival and decrease heart failure hospitalizations in the ATTR-ACT trial. Earlier tafamidis use appeared to be more beneficial, as reflected by NYHA class I and II patients being associated with lower mortality and hospitalizations compared to NYHA class III. Increased awareness will likely lead to an increasing number of ATTR-CM patients being diagnosed with concerns regarding applicability of ATTR-ACT criteria on these patients.

Purpose

To investigate ATTR-CM phenotypic presentation trends based on initial clinical, biomarkers and transthoracic echocardiographic (TTE) data.

Methods

From 2005–2020, 116 ATTR-CM patients were seen at our amyloidosis center, who were stratified into 3 time periods based on the date of diagnosis: Early (21 patients, pre-2016), Mid (46 patients, 2016–2018), and Recent (49 patients, 2018–2020). ATTR-CM diagnosis was established based on the standard criteria of confirmed ATTR variant + typical TTE features; histological confirmation endomyocardial biopsy; or typical diffuse cardiac tracer uptake on bone scintigraphy while ruling out light chain amyloidosis. With less typical imaging, cardiac MRI typically served as a confirmatory test prior to pursuing histological confirmation. Demographics, cardiac biomarkers, diagnostic method used, and TTE variables that raise the suspicion of ATTR-CM were compared across time periods using one-way ANOVA test and Fischer's exact test.

Results

There was a significant change in the predominant method of diagnosis with the majority of patients in the Early time period diagnosed by endomyocardial biopsy, whereas in the Recent time period the majority of patients were diagnosed via pyrophosphate scintigraphy (Figure). Despite increasing number of patients being diagnosed, the clinical phenotype at diagnosis did not change significantly with similar proportion of patients NYHA class I/II, median daily diuretic dose, biomarkers, having at least one heart failure hospitalization prior to diagnosis, and similar TTE phenotype (Table). Only the age at diagnosis significantly increased across time periods. Women represented the minority of patients across all time periods.

Conclusion

Despite the increased awareness of ATTR-CM, there have been no major changes in the clinical, cardiac biomarker, or TTE phenotype on presentation in patients referred to our center for suspicion or a diagnosis of ATTR-CM. Our findings challenge the assumption that patients with ATTR-CM are being identified earlier with milder phenotypes. Women with ATTR-CM likely remain largely undiagnosed in our community. Continued education and knowledge dissemination are essential to identify ATTR-CM patients earlier to achieve better outcomes in this population.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Pranav Chandrashekar is supported by an educational grant from Pfizer, Inc paid to Oregon Health and Science University. Table 1

Primary care teams' experiences of delivering mental health care during the COVID-19 pandemic: a qualitative study

Background

Integrated primary care teams are ideally positioned to support the mental health care needs arising during the COVID-19 pandemic. Understanding how COVID-19 has affected mental health care delivery within primary care settings will be critical to inform future policy and practice decisions during the later phases of the pandemic and beyond. The objective of our study was to describe the impact of the COVID-19 pandemic on primary care teams’ delivery of mental health care.

Methods

A qualitative study using focus groups conducted with primary care teams in Ontario, Canada. Focus group data was analysed using thematic analysis.

Results

We conducted 11 focus groups with 10 primary care teams and a total of 48 participants. With respect to the impact of the COVID-19 pandemic on mental health care in primary care teams, we identified three key themes: i) the high demand for mental health care, ii) the rapid transformation to virtual care, and iii) the impact on providers.

Conclusions

From the outset of the COVID-19 pandemic, primary care quickly responded to the rising mental health care demands of their patients. Despite the numerous challenges they faced with the rapid transition to virtual care, primary care teams have persevered. It is essential that policy and decision-makers take note of the toll that these demands have placed on providers. There is an immediate need to enhance primary care’s capacity for mental health care for the duration of the pandemic and beyond.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-021-01496-8.

A phase I study of binimetinib (MEK 162), a MEK inhibitor, plus carboplatin and pemetrexed chemotherapy in non-squamous non-small cell lung cancer

INTRODUCTION

MEK inhibition is a potential therapeutic strategy in non-small cell lung cancer (NSCLC). This phase I study evaluates the MEK inhibitor binimetinib plus carboplatin and pemetrexed in stage IV non-squamous NSCLC patients (NCT02185690).

METHODS

A standard 3 + 3 dose-escalation design was used. Binimetinib 30 mg BID (dose level 1 [DL1]) or 45 mg BID (dose level 2 [DL2]) was given with standard doses of carboplatin and pemetrexed using an intermittent dosing schedule. The primary outcome was determination of the recommended phase II dose (RP2D) and safety of binimetinib. Secondary outcomes included efficacy, pharmacokinetics, and an exploratory analysis of response based on mutation subtype.

RESULTS

Thirteen patients (6 DL1, 7 DL2) were enrolled: 7 KRAS, 5 EGFR, and 1 NRAS mutation. The RP2D was binimetinib 30 mg BID. Eight patients (61.5%) had grade 3/4 adverse events, with dose limiting toxicities in 2 patients at DL2. Twelve patients were evaluated for response, with an investigator-assessed objective response rate (ORR) of 50% (95% CI 21.1%-78.9%; ORR 33.3% by independent-review, IR), and disease control rate 83.3% (95% CI 51.6%-97.9%). Median progression free survival (PFS) was 4.5 months (95% CI 2.6 months-NA), with a 6-month and 12-month PFS rate of 38.5% (95% CI 19.3%-76.5%) and 25.6% (95% CI 8.9%-73.6%), respectively. In an exploratory analysis, KRAS/NRAS-mutated patients had an ORR of 62.5% (ORR 37.5% by IR) vs. 25% in KRAS/NRAS wild-type patients. In MAP2K1-mutated patients, the ORR was 42.8%.

CONCLUSION

The addition of binimetinib to carboplatin and pemetrexed appears to have manageable toxicity with evidence of activity in advanced non-squamous NSCLC.

Prognostic significance of genome-wide DNA methylation profiles within the randomised, phase 3, EORTC CATNON trial on non-1p/19q deleted anaplastic glioma

Background

Survival in patients with IDH1/2-mutant (mt) anaplastic astrocytomas is highly variable. We have used the prospective phase 3 CATNON trial to identify molecular factors related to outcome in IDH1/2mt anaplastic astrocytoma patients.

Methods

The CATNON trial randomized 751 adult patients with newly diagnosed 1p/19q non-codeleted anaplastic glioma to 59.4 Gy radiotherapy +/− concurrent and/or adjuvant temozolomide. The presence of necrosis and/or microvascular proliferation was scored at central pathology review. Infinium MethylationEPIC BeadChip arrays were used for genome-wide DNA methylation analysis and the determination of copy number variations (CNV). Two DNA methylation-based tumor classifiers were used for risk stratification. Next-generation sequencing (NGS) was performed using 1 of the 2 glioma-tailored NGS panels. The primary endpoint was overall survival measured from the date of randomization.

Results

Full analysis (genome-wide DNA methylation and NGS) was successfully performed on 654 tumors. Of these, 432 tumors were IDH1/2mt anaplastic astrocytomas. Both epigenetic classifiers identified poor prognosis patients that partially overlapped. A predictive prognostic Cox proportional hazard model identified that independent prognostic factors for IDH1/2mt anaplastic astrocytoma patients included; age, mini-mental state examination score, treatment with concurrent and/or adjuvant temozolomide, the epigenetic classifiers, PDGFRA amplification, CDKN2A/B homozygous deletion, PI3K mutations, and total CNV load. Independent recursive partitioning analysis highlights the importance of these factors for patient prognostication.

Conclusion

Both clinical and molecular factors identify IDH1/2mt anaplastic astrocytoma patients with worse outcome. These results will further refine the current WHO criteria for glioma classification.

Interprofessional primary care during COVID-19: a survey of the provider perspective

BACKGROUND

Interprofessional primary care (IPC) teams provide comprehensive and coordinated care and are ideally equipped to support those populations most at risk of adverse health outcomes during the COVID-19 pandemic, including older adults, and patients with chronic physical and mental health conditions. There has been little focus on the experiences of healthcare teams and no studies have examined IPC practice during the early phase of the COVID-19 pandemic. The objective of the study was to describe the state of interprofessional health provider practice within IPC teams during the COVID-19 pandemic.

METHODS

Observational cross-sectional design. A web-based survey was deployed to IPC providers working in team-based primary care clinics in the province of Ontario, Canada. The survey included 26 close-ended and six open-ended questions. Close-ended questions were analyzed using descriptive statistics. Content analysis was used to analyze the open-ended questions.

RESULTS

445 surveys were included in the final analysis. Service delivery shifted from in-person care (77% pre-COVID-19) to telephone (76.5% during the COVID-19 pandemic). Less than half of the respondents (40%) reported receiving any training for virtual delivery. Wait times to access team members were reported to have decreased. There has also been a shift in what IPC providers report as the most commonly seen conditions, with increases in visits related to mental health concerns, acute infections (including COVID-19), social isolation, and resource navigation. Respondents also reported a reduction in healthcare provision for multiple chronic conditions including diabetes, cardiovascular disease, and chronic pain.

CONCLUSIONS

IPC teams are rapidly shifting their practice to supporting their patients during the pandemic. A surge in mental health issues has been seen and is expected to continue to increase in response to COVID-19. Understanding early experiences can help plan for future pandemic waves.

Endodontic implications of a patient with arteriovenous malformation: a case report and literature review

AIM

To present the endodontic management of a patient diagnosed with a high-flow arteriovenous malformation (AVM) requiring root canal treatment and to discuss the relevant endodontic literature for this rare but significant problem.

SUMMARY

AVM is a complex communication of an artery and a vein in which the oxygenated blood is forced away from the intended tissue. The incidence of its occurrence in the face and neck is rare, and when present, the most common sign is gingival bleeding. Arteriovenous malformation is both a diagnostic and therapeutic challenge for dentists. Also, there is ambiguity regarding the precautions to be taken whilst doing endodontic procedures in such cases. Hence, there is a need to understand the disease process and its implications in order to prevent life-threatening complications during treatment. This case report highlights the successful endodontic management of a cariously exposed right maxillary second premolar in a patient diagnosed with high-flow AVM. On an orthopantomogram, the AVM was spreading in the left submandibular space involving the left ramus area. The clinical findings of limited mouth opening with inter-appointment swelling and trismus during treatment made the case unusual and challenging. This paper addresses the current understanding of the classification, diagnosis, clinical features and endodontic management, together with specific guidelines and recommendations whilst performing endodontic procedures in AVM cases.

KEY LEARNING POINTS

The classification and oral manifestations of AVM must be known and understood. Practitioners should be aware of the radiographic appearance of AVM. Recommended precautions should be taken when carrying out restorative and endodontic procedures in a patient with AVM. Antibiotic prophylaxis may be considered before endodontic treatment in a patient with AVM. Multidisciplinary treatment planning may be required.

The evolving treatment landscape of hepatocellular carcinoma: more choices, more responsibility

Hepatocellular carcinoma (hcc) is the 4th most common cause of cancer-related deaths worldwide1 [...]

Accurate detection of atrial fibrillation using a smartphone remains uncertain: a systematic review and meta-analysis

Introduction

Early diagnosis of atrial fibrillation (AF) is essential to reduce complications such as stroke, and improve patient quality of life. Novel screening techniques using smartphone camera photoplethysmography (PPG) can be used for AF detection, but their clinical applicability remains unclear.

Purpose

To assess the diagnostic accuracy of smartphone PPG compared to conventional ECG for AF detection.

Methods

We performed a systematic review of MEDLINE, EMBASE, Cochrane library, and other databases (1980-October 2019), including any study or abstract where smartphone finger-tip PPG was compared with a reference ECG (1, 3 or 12-lead). Outcomes were sensitivity (SE), specificity (SP), positive and negative predictive value (PPV; NPV) and overall accuracy. Bivariate hierarchical random effects meta-analysis was performed for studies with confidence intervals for SE and SP, and funnel plots were used to identify publication bias. Study quality was assessed using the established QUADAS-2 tool by two independent graders.

Results

1350 publications were screened, of which 17 studies were included in the systematic review (7 full text publications and 10 abstracts), providing 21 comparisons of accuracy for AF detection. Most studies were based in secondary care and small (range n=33 to 1095), with a total of 5469 participants including 1384 with AF. Only 4 studies were multicentre. Smartphone applications used were Cardiio Rhythm, Fibricheck, Preventicus and Heartbeats, with 7 studies not specifying the tool used. Overall SE and SP for AF detection were high, ranging from 76 to 100%, and 85 to 100% respectively. PPV ranged from 54 to 100% and NPV from 77 to 100%, with overall accuracy between 61 and 99%. The meta-analysis included 12 comparisons from 10 studies (n=2714; 936 with AF). The pooled SE was 93% (95% CI 90–96%) and SP 97% (95% CI 95–99%); Figure 1A. QUADAS-2 assessment demonstrated poor quality of studies overall, with a high or unclear risk of bias in at least one domain for all studies. There was clear evidence of publication bias; Figure 1B.

Conclusions

PPG offers the potential for large scale, non-invasive, patient-led screening of AF. However, current evidence is limited to biased, low quality studies often with unrealistic results for AF detection. These are insufficient to advise clinicians on the true value of current smartphone PPG technology.

Figure 1. Meta-analysis & publication bias

Funding Acknowledgement

Type of funding source: Public grant(s) – EU funding. Main funding source(s): BigData@Heart EU/EFPIA IMI 116074.

Time saving, simple and reproducible method to quantify left ventricular function in patients with atrial fibrillation

Introduction

Echocardiography is essential for the management of patients with atrial fibrillation (AF), but current methods are time consuming and lack any evidence of reproducibility.

Purpose

To compare conventional averaging of consecutive beats with an index beat approach, where systolic and diastolic measurements are taken once after two prior beats with a similar RR interval (not more than 60 ms difference).

Methods

Transthoracic echocardiography was performed using a standardized and blinded protocol in patients enrolled into the RAte control Therapy Evaluation in permanent AF randomised controlled trial (RATE-AF; NCT02391337). AF was confirmed in all patients with a preceding 12-lead ECG. A minimum of 30-beat loops were recorded. Left ventricular function was determined using the recommended averaging of 5 and 10 beats and using the index beat method, with observers blinded to clinical details. Complete loops were used to calculate the within-beat coefficient of variation (CV) and intraclass correlation coefficient (ICC) for Simpson's biplane left ventricular ejection fraction (LVEF), global longitudinal strain (GLS) and filling pressure (E/e').

Results

160 patients (median age 75 years (IQR 69–82); 46% female) were included, with median heart rate 100 beats/min (IQR 86–112). For LVEF, the index beat had the lowest CV of 32% compared to 51% for 5 consecutive beats and 53% for 10 consecutive beats (p&lt;0.001). The index beat also had the lowest CV for GLS (26% versus 43% and 42%; p&lt;0.001) and E/e' (25% versus 41% and 41%; p&lt;0.001; see Figure for ICC comparison). Intra-operator reproducibility, assessed by the same operator from two different recordings in 50 patients, was superior for the index beat with GLS bias −0.5 and narrow limits of agreement (−3.6 to 2.6), compared to −1.0 for 10 consecutive beats (−4.0 to 2.0). For inter-operator variability, assessed in 18 random patients, the index beat also showed the smallest bias with narrow confidence intervals (CI). Using a single index beat did not impact on the validity of LVEF, GLS or E/e' measurement when correlated with natriuretic peptides. Index beat analysis substantially shortened analysis time; 35 seconds (95% CI 35 to 39 seconds) for measuring E/e' with the index beat versus 98 seconds (95% CI 92 to 104 seconds) for 10 consecutive beats (see Figure).

Conclusion

Index beat determination of left ventricular function improves reproducibility, saves time and does not compromise validity compared to conventional quantification in patients with heart failure and AF. After independent validation, the index beat method should be adopted into routine clinical practice.

Comparison for measurement of E/e'

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Institute of Health Research UK

Hemoglobin level at stabilization is associated with long-term all-cause mortality in patients with left-sided endocarditis, a POET substudy

Background

Left-sided infectious endocarditis (IE) has a high 1-year mortality. Anemia is a common finding in patients with IE, yet little is known about frequency, severity, and associated outcomes in this setting.

Purpose

To examine the relationship between Hemoglobin (Hgb) level measured at IE stabilization (time of randomization) in the Partial Oral versus intravenous Antibiotic Treatment of Endocarditis (POET) trial - and long-term all-cause mortality.

Methods

In the POET trial, 400 patients with left-sided IE were randomized, after medical and/or surgical stabilization, to conventional antibiotic treatment or partial oral treatment. Only non-surgically treated patients were considered in this study. Patients were divided by quartiles into four groups based on Hgb level at randomization.

Results

We examined 248 patients with non-surgically treated IE. Median time from diagnosis of IE to randomization was 14 days (IQ 12–19). At long-term follow-up (median 3.2 years, IQ 2.18–4.60), 71 patients had died (28.6%). Patients in the lowest quantile (Hgb ≤6.0 mmol) had a HR of 4.17 (95% CI 1.81–9.61, p&lt;0.001) for death compared to patients in the highest quantile (Hgb &gt;7.5 mmol/L). This association remained significant after multivariable adjustment for age, sex, renal disease, C-Reactive Protein, and Prosthetic heart valve (HR 2.69, 95% CI 1.11–6.50); p=0.028).

Conclusion

Low Hemoglobin level at stabilization in patients with IE was associated with an increased risk of long-term mortality. Whether intensified treatment of anemia in patients with IE could improve long-term outcome requires investigation.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): The Danish Heart Foundation, The Capital Regions Research Council

Under-mask beard cover (Singh Thattha technique) for donning respirator masks in COVID-19 patient care

Tight-fitting filtering facepiece (FFP3) face masks are essential respiratory protective equipment during aerosol-generating procedures in the coronavirus disease 2019 (COVID-19) environment, and require a fit test to assess mask–face seal competency. Facial hair is considered to be an impediment for achieving a competent seal. We describe an under-mask beard cover called the Singh Thattha technique, which obtained a pass rate of 25/27 (92.6%) by qualitative and 5/5 (100%) by quantitative fit test in full-bearded individuals. Sturdier versions of FFP3 were more effective. For individuals for whom shaving is not possible, the Singh Thattha technique could offer an effective solution to safely don respirator masks.

Impact of COVID-19 on Canadian medical oncologists and cancer care: Canadian Association of Medical Oncologists survey report

Background

The covid-19 pandemic has presented unprecedented professional and personal challenges for the oncology community. Under the auspices of the Canadian Association of Medical Oncologists, we conducted an online national survey to better understand the impact of the pandemic on the medical oncology community in Canada.

Methods

An English-language multiple-choice survey, including questions about demographics, covid-19 risk, use of personal protective equipment (ppe), personal challenges, and chemotherapy management was distributed to Canadian medical oncologists. The survey was open from 30 March to 4 April 2020, and attracted 159 responses.

Results

More than 70% of medical oncologists expressed moderate-to-extreme concern about personally contracting covid-19 and about family members or patients (or both) contracting covid-19 from them. Despite that high level of concern, considerable variability in the use of ppe in direct cancer care was reported at the time of this survey, with 33% of respondents indicating no routine ppe use at their institutions and 69% indicating uncertainty about access to adequate ppe. Of the respondents, 54% were experiencing feelings of nervousness or anxiety on most days, and 52% were having feelings of depression or hopelessness on at least some days. Concern about aging parents or family and individual wellness represented the top personal challenges identified. The management of cancer patients has been affected, with adoption of telemedicine reported by 82% of respondents, and cessation of clinical trial accrual reported by 54%. The 3 factors deemed most important for treatment decision-making were■ cancer prognosis and anticipated benefit from treatment,■ risk of treatment toxicity during scarce health care access, and■ patient risk of contracting covid-19.

Conclusions

This report describes the results of the first national survey assessing the impact of the covid-19 on Canadian medical oncologists and how they deliver systemic anticancer therapies. We hope that these data will provide a framework to address the challenges identified.

Cautious optimism-the current role of immunotherapy in gastrointestinal cancers

Immunotherapy has been described as the "fourth pillar" of oncology treatment, in conjunction with surgery, chemotherapy, and radiotherapy. However, the role of immunotherapy in gastrointestinal tumours is still evolving. Data for checkpoint inhibition in esophagogastric, hepatocellular, colorectal, and anal squamous cell carcinomas are expanding. In phase iii trials in the second-line setting, PD-1 inhibitors have demonstrated positive results for the subset of esophageal cancers that are positive for PD-L1 at a combined positive score of 10 or more. Based on results of phase ii trials, PD-1 inhibitors were approved in North America for use in PD-L1-positive chemorefractory gastric cancers, in hepatocellular carcinoma after sorafenib exposure, and in treatment-refractory deficient mismatch repair (dmmr) or high microsatellite instability (msi-h) tumours, regardless of tissue site. Combination use of PD-1 and ctla-4 inhibitors has been approved by the U.S. Food and Drug Administration for chemorefractory dmmr or msi-h colorectal cancer. Responses to checkpoint inhibition are durable, particularly in the dmmr or msi-h colorectal cancer cohort. As trials of combination immunotherapy, immunotherapy in combination with other systemic therapies, and immunotherapy in combination with other treatment modalities move forward in multiple tumour sites, cautious optimism is called for. The treatment landscape is continually changing, and expanded indications are likely to be just around the corner.

Are we finally moving toward personalized therapy in colorectal cancer?

Colorectal cancer (crc) will represent 12% of all new cancer cases and 12% of all cancer deaths in 2019, with more than 26,300 Canadians being diagnosed and 9500 Canadians dying of crc this year1.[...]

Detecting Neurodevelopmental Toxicity of Domoic Acid and Ochratoxin A Using Rat Fetal Neural Stem Cells

Currently, animal experiments in rodents are the gold standard for developmental neurotoxicity (DNT) investigations; however, testing guidelines for these experiments are insufficient in terms of animal use, time, and costs. Thus, alternative reliable approaches are needed for predicting DNT. We chose rat neural stem cells (rNSC) as a model system, and used a well-known neurotoxin, domoic acid (DA), as a model test chemical to validate the assay. This assay was used to investigate the potential neurotoxic effects of Ochratoxin A (OTA), of which the main target organ is the kidney. However, limited information is available regarding its neurotoxic effects. The effects of DA and OTA on the cytotoxicity and on the degree of differentiation of rat rNSC into astrocytes, neurons, and oligodendrocytes were monitored using cell-specific immunofluorescence staining for undifferentiated rNSC (nestin), neurospheres (nestin and A2B5), neurons (MAP2 clone M13, MAP2 clone AP18, and Doublecortin), astrocytes (GFAP), and oligodendrocytes (A2B5 and mGalc). In the absence of any chemical exposure, approximately 46% of rNSC differentiated into astrocytes and neurons, while 40% of the rNSC differentiated into oligodendrocytes. Both non-cytotoxic and cytotoxic concentrations of DA and OTA reduced the differentiation of rNSC into astrocytes, neurons, and oligodendrocytes. Furthermore, a non-cytotoxic nanomolar (0.05 µM) concentration of DA and 0.2 µM of OTA reduced the percentage differentiation of rNSC into astrocytes and neurons. Morphometric analysis showed that the highest concentration (10 μM) of DA reduced axonal length. These indicate that low, non-cytotoxic concentrations of DA and OTA can interfere with the differentiation of rNSC.

P3665Prevalence of infective endocarditis in patients with positive blood cultures: a Danish nationwide study

Background

Increasing attention has been given to the risk of infective endocarditis (IE) in patients with certain blood stream infections (BSI). Previous studies have been conducted on selected patient cohorts, yet unselected data are sparse.

Purpose

To investigate the nationwide prevalence of diagnosed IE in BSIs with bacteria typically associated with IE.

Methods

By crosslinking nationwide registries from 2010–2016, we identified patients with BSIs typically associated with IE: Enterococcus faecalis, Staphylococcus, Streptococcus spp., and coagulase negative staphylococci (CoNS) and examined the concurrent IE prevalence. A trend test was used to examine temporal changes in the prevalence of IE.

Results

In total 60,119 BSIs, distributed with 15,407, 16,790, and 27,922 BSIs were identified in the periods of 2010–2011, 2012–2013, and 2014–2016, respectively.

Patients with E. Faecalis had the highest prevalence of diagnosed IE (16.3%) followed by S. aureus (10.2%), Streptococcus spp. (7.3%), and CoNS (1.6%) (Figure). During the study period, the prevalence of IE among patients with E. faecalis increased significantly (p=0.003), Male patients had higher prevalence of IE for all microorganisms investigated compared with females. A significant increase in the prevalence of IE was seen for E. faecalis, Streptococcus spp., and CoNS with increasing age.

Percent with endocarditis

Conclusion

For E. faecalis BSI, 1 in 6 had IE, for S. aureus BSI 1 in 10 had IE, and for Streptococcus spp. 1 in 14 had IE. Our results support screening for IE in patients with E. faecalis, S. aureus, or Streptococcus spp. BSI in order to offer appropriate therapy.

P3663Prevalence of infective endocarditis in patients with a left-sided heart valve prosthesis: a nationwide study

Background

Increasing attention has been given to patients with blood stream infection (BSI) and the concurrent prevalence of infective endocarditis (IE). However, there exist a gap in knowledge on the prevalence of IE among patients with a left-sided heart valve prosthesis and BSI.

Purpose

To examine the prevalence between different BSI and IE in patients with a left-sided heart valve prosthesis.

Methods

By linking Danish nationwide registries, we were able to identify patients with a left-sided prosthetic heart valve and first-time BSI of interest (Enterococcus faecalis, Staphylococcsus aureus, streptococci species (spp.), and coagulase negative staphylococci [CoNS]) in the period of 2010–2016. Concurrent admission for IE was identified from the Danish National Patient Registry in a period of up to 14 days after the BSI.

Results

A total of 1,465 patients with BSI were included (1,319 patients with an aortic valve prosthesis [82.6% bioprosthetic] and 146 patients with a mitral valve prosthesis [48.6% bioprosthetic]). Among the included patients, 244 had E. faecalis (median age: 78.3 years, 77.0% male), 301 had S. aureus (median age: 76.9 years, 69.1% male), 401 had streptococci spp. (median age: 78.0 years, 69.1% male) and 519 had CoNS (median age: 76.4 years, 64.2% male). The percentage of patients with a diagnosis of IE in relation to the BSI was 44.3%, 33.6%, 34.4%, and 7.9% for E. faecalis, S. aureus, streptococci spp., and CoNS, respectively. No difference in the overall results was seen by type of valve prosthesis, sex, or age group.

Percentage of patients with endocarditis

Conclusion

In patients with a left-sided heart valve prosthesis, IE was diagnosed in almost half of the patients with E. faecalis, in 1/3 with S. aureus or streptococci spp. and in 1 in 12 with CoNS BSI. Future studies may try to explain why some microbes are more likely to cause prosthetic heart valve endocarditis, than others are.

What is a clinically meaningful survival benefit in refractory metastatic colorectal cancer?

Assessment of the clinical benefit of cancer treatments can be highly subjective, influenced by both perspective and context. Such assessments are required in regulatory and policy decision-making, but consistency between jurisdictions is often lacking. Clear and consistent standards for determining when a treatment offers a meaningful benefit, relative to the current standard of care, can help to address issues of equity and transparency in health technology assessment. For metastatic colorectal cancer (mcrc), no standardized Canadian definition of clinically meaningful benefit has yet been proposed. Colorectal Cancer Canada therefore convened a group of medical oncologists expert in colorectal cancer to review the literature about clinical significance. The resulting consensus is intended to apply to any therapeutic agent being considered in the setting of chemotherapy-refractory mcrc. It was agreed that overall survival is the appropriate measure of clinical efficacy in chemorefractory mcrc. As quantitative targets for efficacy, an improvement of 2 months or more in median overall survival or a hazard ratio for survival of 0.75 or lower (or both) are proposed as the threshold for clinically meaningful benefit. That threshold could be influenced by a treatment's effect on quality of life. Treatment toxicity is also relevant to the assessment of clinical benefit in this setting, specifically when significant differences in treatment tolerability are evident.

Hypertension as a predictor of advanced colorectal cancer outcome and cetuximab treatment response

Background

Adrenergic receptor stimulation is involved in the development of hypertension (htn) and has been implicated in cancer progression and dissemination of metastases in various tumours, including colon cancer. Adrenergic antagonists such as beta-blockers (bbs) demonstrate inhibition of invasion and migration in colon cancer cell lines and have been associated with decreased mortality in colorectal cancer (crc). We examined the association of baseline htn and bb use with overall (os) and progression-free survival (pfs) in patients with pretreated, chemotherapy refractory, metastatic crc (mcrc). We also examined baseline htn as a predictor of cetuximab efficacy.

Methods

Using data from the Canadian Cancer Trials Group co.17 study [cetuximab vs. best supportive care (bsc)], we coded baseline htn and use of anti-htn medications, including bbs, for 572 patients. The chi-square test was used to assess the associations between those variables and baseline characteristics. Cox regression models were used for univariate and multivariate analyses of os and pfs by htn diagnosis and bb use.

Results

Baseline htn, bb use, and anti-htn medication use were not found to be prognostic for improved os. Baseline htn and bb use were not significant predictors of cetuximab benefit.

Conclusions

In chemorefractory mcrc, neither baseline htn nor bb use is a significant prognostic factor. Baseline htn and bb use are not predictive of cetuximab benefit. Further investigation to determine whether baseline htn or bb use have a similarly insignificant impact on prognosis in patients receiving earlier lines of treatment remains warranted.