Poor Concordance Between Cancer Antigen-125 and RECIST Assessment for Progression in Patients With Platinum-Sensitive Relapsed Ovarian Cancer on Maintenance Therapy With a Poly(ADP-ribose) Polymerase Inhibitor.

PURPOSE: Cancer antigen-125 (CA-125) is recommended by treatment guidelines and widely used to diagnose ovarian cancer recurrence. The value of CA-125 as a surrogate for disease progression (PD) and its concordance with radiologic progression are unclear, particularly for women with platinum-sensitive relapsed ovarian cancer (PSROC) who have responded to chemotherapy and treated with maintenance poly(ADP-ribose) polymerase inhibitor (PARPi). METHODS: In this pooled analysis of four randomized trials of maintenance PARPi or placebo (Study 19, SOLO2, ARIEL3, and NOVA), we extracted data on CA-125 PD as defined by Gynecologic Cancer InterGroup criteria and RECIST v1.1. We evaluated the concordance between CA-125 and RECIST PD and reported on the negative predictive value (NPV) and positive predictive value (PPV). RESULTS: Of 1,262 participants (n = 818 PARPi, n = 444 placebo), 403 (32%) had CA-125 PD, and of these, 366 had concordant RECIST PD (PPV, 91% [95% CI, 88 to 93]). However, of 859 (68%) without CA-125 PD, 382 also did not have RECIST PD (NPV, 44% [95% CI, 41 to 48]). Within the treatment arms, PPV remained high (PARPi, 91% [95% CI, 86 to 94]; placebo, 91% [95% CI, 86 to 95]) but NPV was lower on placebo (PARPi, 53% [95% CI, 49 to 57]; placebo, 25% [95% CI, 20 to 31]). Of 477 with RECIST-only PD, most (95%) had a normal CA-125 at the start of maintenance therapy and the majority (n = 304, 64%) had CA-125 that remained within normal range. Solid organ recurrence without peritoneal disease was more common in those with RECIST-only PD than in those with CA-125 and RECIST PD (36% v 24%; P < .001). CONCLUSION: In patients with PSROC treated with maintenance PARPi, almost half with RECIST PD did not have CA-125 PD, challenging current guidelines. Periodic computed tomography imaging should be considered as part of surveillance, particularly in those with a normal CA-125 at the start of maintenance therapy and on treatment.

Framework for the Use of External Controls to Evaluate Treatment Outcomes in Precision Oncology Trials.

Advances in genomics have enabled anticancer therapies to be tailored to target specific genomic alterations. Single-arm trials (SATs), including those incorporated within umbrella, basket, and platform trials, are widely adopted when it is not feasible to conduct randomized controlled trials in rare biomarker-defined subpopulations. External controls (ECs), defined as control arm data derived outside the clinical trial, have gained renewed interest as a strategy to supplement evidence generated from SATs to allow comparative analysis. There are increasing examples demonstrating the application of EC in precision oncology trials. The prospective application of EC in conducting comparative studies is associated with distinct methodological challenges, the specific considerations for EC use in biomarker-defined subpopulations have not been adequately discussed, and a formal framework is yet to be established. In this review, we present a framework for conducting a prospective comparative analysis using EC. Key steps are (1) defining the purpose of using EC to address the study question, (2) determining if the external data are fit for purpose, (3) developing a transparent study protocol and a statistical analysis plan, and (iv) interpreting results and drawing conclusions on the basis of a prespecified hypothesis. We specify the considerations required for the biomarker-defined subpopulations, which include (1) specifying the comparator and biomarker status of the comparator group, (2) defining lines of treatment, (3) assessment of the biomarker testing panels used, and (4) assessment of cohort stratification in tumor-agnostic studies. We further discuss novel clinical trial designs and statistical techniques leveraging EC to propose future directions to advance evidence generation and facilitate drug development in precision oncology.

Characteristics and post-metastasis survival of recurrent metastatic breast cancer over time - An Australian population-based record linkage study, 2001-2016.

AIM: To assess population-level characteristics and post-metastasis survival of people with recurrent metastatic breast cancer (rMBC) during a period when new publicly-subsidised adjuvant and metastatic systemic therapies became available. METHODS: Record linkage study of females in NSW Cancer Registry (NSWCR) diagnosed with non-metastatic breast cancer (BC) in 2001-2002 (C1) and 2006-2007 (C2). We identified first rMBC from NSWCR, administrative hospital records, dispensed medicines and radiotherapy services (2001-2016). We used death registrations to estimate cumulative incidence of BC death. RESULTS: The analysis included 2267 women with rMBC (C1:1210, C2:1057). Compared to C1, C2 had access to adjuvant HER2-targeted therapy and were more likely to have received adjuvant chemotherapy (C1:38%, C2:47%) and aromatase inhibitors (C1:52%, C2:73%, of those dispensed endocrine therapy). Five-year probability of BC death was 65% (95%CI:62-68%) in C1 and 63% (95%CI:60-66%) in C2. Regional disease (T4 or N + ) at initial BC diagnosis (C1:62%, C2:68%), and age ≥ 70 years at first metastasis (C1:27%, C2:31%) were more common in C2 and had poorer prognosis. Five-year probability of BC death was lower in C2 than C1 for treatment-defined HER2-positive BC (C1:72% 95%CI:63-79%; C2:52% 95%CI 45-60%) and those dispensed chemotherapy alone (C1:76% 95%CI:69-82, C2:67% 95%CI:59-74%, p = 0.01), but not treatment-defined hormone receptor-positive HER2-negative BC (C1:60% 95%CI 56-63%, C2:64% 95%CI 60-68%). CONCLUSIONS: Despite less favourable prognostic characteristics in C2, BC-related survival following rMBC was similar between the two cohorts; and improved for women with HER2-positive tumours. These findings support the real-world benefits of newer treatments for rMBC.

Decline in the Incidence of Distant Recurrence of Breast Cancer: A Population-Based Health Record Linkage Study, Australia 2001-2016.

BACKGROUND: We investigated differences in cumulative incidence of first distant recurrence (DR) following non-metastatic breast cancer over a time period when new adjuvant therapies became available in Australia. METHODS: We conducted a health record linkage study of females with localized (T1-3N0) or regional (T4 or N+) breast cancer in the New South Wales Cancer Registry in 2001 to 2002 and 2006 to 2007. We linked cancer registry records with administrative records from hospitals, dispensed medicines, radiotherapy services, and death registrations to estimate the 9-year cumulative incidence of DR and describe use of adjuvant treatment. RESULTS: The study included 13,170 women (2001-2002 n = 6,338, 2006-2007 n = 6,832). The 9-year cumulative incidence of DR was 3.6% [95% confidence interval (CI), 2.3%-4.9%] lower for 2006-2007 diagnoses (15.0%) than 2001-2002 (18.6%). Differences in the annual hazard of DR between cohorts were largest in year two. DR incidence declined for localized and regional disease. Decline was largest for ages <40 years (absolute difference, 14.4%; 95% CI, 8.3%-20.6%), whereas their use of adjuvant chemotherapy (2001-2002 49%, 2006-2007 75%) and HER2-targeted therapy (2001-2002 0%, 2006-2007 16%) increased. DR did not decline for ages ≥70 years (absolute difference, 0.9%; 95% CI, -3.6%-1.8%) who had low use of adjuvant chemotherapy and HER2-targeted therapy. CONCLUSIONS: This whole-of-population study suggests that DR incidence declined over time. Decline was largest for younger ages, coinciding with changes to adjuvant breast cancer therapy. IMPACT: Study findings support the need for trials addressing questions relevant to older people and cancer registry surveillance of DR to inform cancer control programs.

Managing understandings of palliative care as more than care immediately before death: Evidence from observational analysis of consultations.

BACKGROUND: Evidence suggests that public, and some professional, understandings of palliative care are limited to care provided immediately before death, which contrasts palliative care's scope as care provided across a range of illness stages. OBJECTIVE: To examine how clinicians manage patients' understandings of palliative care during initial consultations. DESIGN: Initial palliative care consultations were video-recorded and analysed using conversation analytic methods. SETTING/PARTICIPANTS: Consultations were recorded in a specialist palliative care outpatient unit within an Australian public hospital. Participants included 20 newly referred patients and their families, and three palliative care clinicians. RESULTS: During initial consultations, it was observed that specialist palliative care clinicians frequently managed the possibility that patients may understand palliative care as limited to care provided immediately before death. Clinicians used recurrent practices that seemed designed to pre-empt and contradict patients' possible narrow understandings. When discussing the palliative care inpatient unit, clinicians recurrently explained inpatient care could include active treatment and referred to the possibility of being discharged. These practices contradict possible understandings that future admission to the inpatient unit would be solely for care immediately before death. DISCUSSION: The findings demonstrate that palliative care clinicians are aware of possible narrow understandings of their discipline among members of the public. The practices identified show how clinicians pre-emptively manage these understandings to patients newly referred to palliative care. CONCLUSIONS: These findings highlight scope for greater partnership with teams referring patients to palliative care, to assist patients in understanding the range of reasons for their referral. PATIENT OR PUBLIC CONTRIBUTION: The observational method of conversation analysis provides direct insight into matters that are relevant for patients, as raised in their consultations with clinicians. This direct evidence enables analysis of their lived experience, as it occurs, and grounds analysis in observable details of participants' conduct, rather than interpretations of subjective experiences. The patients' contributions, therefore, were to allow observation into their initial palliative care consultations.

Biopsychosocial contexts of timely and adequate prenatal care utilization among women with criminal legal involvement and opioid use disorder.

OBJECTIVE: Pregnant women with criminal legal involvement and opioid use disorder (CL-OUD) living in non-urban regions may be at risk for complex biomedical, psychological, and social barriers to prenatal care and healthy pregnancy. Yet, limited research has explored prenatal care utilization patterns among this subpopulation. This study describes the biopsychosocial factors of pregnant women with a history of criminal legal involvement and opioid use disorder (CL-OUD) associated with timely prenatal care initiation and adequate prenatal care utilization (APNCU). METHODS: Analyses were conducted on a subsample of medical record data from an observational comparative effectiveness study of medication treatment models for pregnant women with diagnosed opioid use disorder (OUD) who received prenatal care in Northern New England between 2015 and 2022. The subsample included women aged ≥ 16 years with documented criminal legal involvement. Analyses included χ2, Fisher exact tests, and multiple logistic regression to assess differences in timely prenatal care and APNCU associated with biopsychosocial factors selected by backwards stepwise regression. RESULTS: Among 317 women with CL-OUD, 203 (64.0%) received timely prenatal care and 174 (54.9%) received adequate care. Timely prenatal care was associated with having two or three prior pregnancies (aOR 2.37, 95% CI 1.07-5.20), receiving buprenorphine at care initiation (aOR 1.85, 95% CI 1.01-3.41), having stable housing (aOR 2.49, 95% CI 1.41-4.41), and being mandated to court diversion (aOR 4.06, 95% CI 1.54-10.7) or community supervision (aOR 2.05, 95% CI 1.16-3.63). APNCU was associated with having a pregnancy-related medical condition (aOR 2.17, 95% CI 1.27-3.71), receiving MOUD throughout the entire prenatal care period (aOR 3.40, 95% CI 1.45-7.94), having a higher number of psychiatric diagnoses (aOR 1.35, 95% CI 1.07-1.70), attending a rurally-located prenatal care practice (aOR 2.14, 95% CI 1.22-3.76), having stable housing (aOR 1.94, 95% CI 1.06-3.54), and being mandated to court diversion (aOR 3.11, 95% CI 1.19-8.15). CONCLUSION: While not causal, results suggest that timely and adequate prenatal care among women with CL-OUD may be supported by OUD treatment, comorbid indications for care, stable access to social resources, and maintained residence in the community (i.e., community-based alternatives to incarceration).

Infant Maternal Perinatal Advanced Care Team: A Pilot Collaboration for Families Facing a Life-Threatening Fetal Diagnosis.

Background: The Infant Maternal Perinatal Advanced Care Team program was launched in 2018 to enhance perinatal palliative care services in Toronto, Canada. Methods: Pilot patients were (1) carrying a fetus with a life-limiting diagnosis and (2) receiving care at the high-risk fetal center. Individualized care included opportunities for establishing goals, labor/delivery planning, grief support, and pediatric palliative care support. Results: A total of 107 patients were included during the two-year clinical pilot program. Of those who continued their pregnancy, 45% had care goals focused on comfort while 55% had goals focused on life prolongation. A significant proportion in both groups experienced a fetal or neonatal death. For babies who received comfort-focused care, one-third were transferred to hospice or home. Conclusions: A comprehensive perinatal palliative care pathway ensures that more families receive options of pre- and postnatal palliative care supports in varied circumstances where there is significant risk of fetal and neonatal mortality.

Informing a collaborative-care model for delivering medication assisted treatment for opioid dependence (MATOD): An analysis of pharmacist, prescriber and patient perceptions.

BACKGROUND: Demand for medication assisted treatment for opioid dependence (MATOD) in Australia exceeds capacity, particularly in rural and regional areas. There is increasing recognition that community pharmacists are well-positioned to take on expanded roles in MATOD delivery, however there has been limited Australian research exploring attitudes of pharmacists, prescribers, and patients to collaborative models of care. OBJECTIVE(S): This study aimed to better understand enablers and barriers to a collaborative model for MATOD, to inform implementation in regions where increases in treatment capacity are urgently needed. METHODS: Semi-structured telephone interviews were conducted with pharmacists (n = 11), prescribers (n = 6), and patients (n = 8) recruited from the Frankston-Mornington Peninsula region in Victoria, Australia, where transport and access to services have impacts on health care utilisation. The COM-B model was used to explore perceptions of pharmacists' capability, opportunity, and motivations for delivering collaborative care. RESULTS: There was strong motivation among healthcare professionals to participate in a collaborative model of care, with the main perceived benefits including improvements in accessibility, convenience, and continuity of care, and leverage of pharmacists' high level of patient engagement. Key barriers identified by both pharmacists and prescribers included a perceived lack of pharmacist skills in some areas (capability) and resources (opportunity) to deliver collaborative care in a community pharmacy setting. Established relationships between all stakeholders (social opportunity) and communication between pharmacists and prescribers were identified as facilitators. Barriers and facilitators aligned with seven key areas: skills, confidence, relationships, patient selection, protocols, communication and resources. CONCLUSIONS: Findings informed the development of a collaborative model that was individualised, protocol based, and supported by training and clear processes. PROJECT IMPACT: This study identifies specific barriers and facilitators to a pharmacist-prescriber collaborative model of care for MATOD. The resulting model will be tested in a hybrid implementation-effectiveness trial in the Frankston-Mornington Peninsula region.

Promoting community stakeholder engagement in research on treatment for pregnant women with opioid use disorder.

Aim: Community stakeholder engagement in research (CSER) can improve research relevance and efficiency as well as prevent harmful practices, particularly for vulnerable populations. Despite potential benefits, researchers lack familiarity with CSER methods. Methods: We describe CSER strategies used across the research continuum, including proposal development, study planning and the first years of a comparative effectiveness study of care for pregnant women with opioid use disorder. Results: We highlight successful strategies, grounded in principles of engagement, to establish and maintain stakeholder relationships, foster bidirectional communication and trust and support active participation of women with opioid use disorder in the research process. Conclusion: CSER methods support research with a disenfranchised population. Future work will evaluate the impact of CSER strategies on study outcomes and dissemination.

Community stakeholder engagement in research on treatment for pregnant women with opioid use disorder builds and maintains stakeholder relationships, fosters communication and trust and supports active patient participation.

Pain management in advanced cancer: physical activity as an outcome - accelerometer feasibility study.

OBJECTIVE: Cancer pain is a common distressing symptom. Numerical Pain Scales (NPS) assess pain but lack information about function and quality of life. This feasibility study assesses the use of triaxial accelerometers to measure function as an outcome measure in pain studies in advanced cancer. METHODS: Advanced cancer participants were recruited from two palliative care services, with an average pain score of ≥3 on NPS. ActiGraph wGT3X-BT Accelerometers were worn for 1 week on the wrist. Patients recorded daily pain scores, Edmonton Symptom Assessment Scale (ESAS) scores, and their daily opioid use. RESULTS: 24 participants were recruited. A total of 142 days of accelerometer data was collected (5.9 days/participant). The average daily step count was 5723.7. The average acceleration was 14.4 milligravity units/day. An average of 93 min/day total activity across all intensities was recorded. No correlation was seen between acceleration or average daily minutes in activity and total daily oral morphine equivalent, ESAS, 'average pain' score or 'worst pain' scores using spearman's correlation coefficients. Overall, participants were satisfied with the study. CONCLUSIONS: Accelerometers are a feasible method to measure activity as an outcome measure in advanced cancer. Further study is required to assess the impact of pain management strategies on function.

Next-generation sequencing, should I use anti-HER2 therapy for HER2-amplified tumors off-label? Illustrating an extrapolation framework.

Background: Next-generation sequencing is used to increase targeted treatment opportunities, particularly for patients who have exhausted standard options. Where randomized controlled trial evidence for a targeted therapy is available for molecular alterations in one tumor type, the dilemma for the clinician is whether 'matching' targeted agents should be recommended off-label for the same molecular alterations detected in other tumor types, for which no trial data are available to guide practice. To judge the likely benefits, it may be possible to extrapolate evidence from cancers where treatment benefits have been established. Methods: We present a framework for assessing the appropriateness of extrapolation using trastuzumab, an anti-HER2 antibody, for HER2-amplified tumors where trastuzumab use would be off-label as an illustrative example. Results: The following should be considered for the tumor type where trastuzumab would be off-label: (a) reliability of the NGS assay for detecting HER2 amplification; (b) criteria for defining HER2 positivity; (c) strength of evidence supporting the actionability of HER2 amplification and trastuzumab; (d) whether better clinical outcomes with trastuzumab are due to a more favorable natural history rather than trastuzumab effect; (e) signals of trastuzumab activity and whether it translates to clinically meaningful benefit; (f) whether the safety profile of trastuzumab differs from established indications; and (g) discussion points for shared decision making (SDM) to facilitate informed consent. Conclusion: We present a systematic approach for appraising evidence to support extrapolating trastuzumab benefits from established indications to off-label applications. Extrapolation criteria and areas of uncertainty to inform SDM are outlined. This framework is potentially generalizable to other tumor-agnostic biomarker-targeted therapy scenarios. It is a practical approach for clinicians to apply in routine practice and should be considered by molecular tumor boards who make off-label recommendations.

Long term risk of distant metastasis in women with non-metastatic breast cancer and survival after metastasis detection: a population-based linked health records study.

OBJECTIVES: To estimate the long term risk of distant metastases (DM) for women with initial diagnoses of non-metastatic breast cancer; to estimate breast cancer-specific and overall survival for women with DM. DESIGN: Population-based health record linkage study. SETTING, PARTICIPANTS: Women diagnosed with localised or regional primary breast cancer recorded in the NSW Cancer Registry, 2001-2002. MAJOR OUTCOME MEASURES: Time from breast cancer diagnosis to first DM, time from first DM to death from breast cancer. SECONDARY OUTCOME: time to death from any cause. RESULTS: 6338 women were diagnosed with non-metastatic breast cancer (localised, 3885; regional, 2453; median age, 59 years [IQR, 49-69 years]). DM were recorded (to 30 September 2016) for 1432 women (23%; median age, 62 years [IQR, 51-73 years]). The 14-year cumulative DM incidence was 22.2% (95% CI, 21.1-23.2%; localised disease: 14.3% [95% CI, 13.2-15.4%]; regional disease: 34.7% [95% CI, 32.8-36.6%]). Annual hazard of DM was highest during the second year after breast cancer diagnosis (localised disease: 2.8%; 95% CI, 2.3-3.3%; regional disease: 9.1%; 95% CI, 7.8-10.3%); from year five it was about 1% for those with localised disease, from year seven about 2% for women with regional disease at diagnosis. Five years after diagnosis, the 5-year conditional probability of DM was 4.4% (95% CI, 3.7-5.1%) for women with localised and 10.4% (95% CI, 9.1-12.0%) for those with regional disease at diagnosis. Median breast cancer-specific survival from first DM record date was 28 months (95% CI, 25-31 months); the annual hazard of breast cancer death after the first DM record declined from 36% (95% CI, 33-40%) during the first year to 14% (95% CI, 11-18%) during the fourth year since detection. CONCLUSIONS: DM risk declines with time from diagnosis of non-metastatic breast cancer, and the annual risk of dying from breast cancer declines with time from initial DM detection. These findings can be used to inform patients at follow-up about changes in risk over time since diagnosis and for planning health services.

Extrapolating evidence for molecularly targeted therapies from common to rare cancers: a scoping review of methodological guidance.

OBJECTIVES: Cancer is increasingly classified according to biomarkers that drive tumour growth and therapies developed to target them. In rare biomarker-defined cancers, randomised controlled trials to adequately assess targeted therapies may be infeasible. Extrapolating existing evidence of targeted therapy from common cancers to rare cancers sharing the same biomarker may reduce evidence requirements for regulatory approval in rare cancers. It is unclear whether guidelines exist for extrapolation. We sought to identify methodological guidance for extrapolating evidence from targeted therapies used for common cancers to rare biomarker-defined cancers. DESIGN: Scoping review. DATA SOURCES: Websites of health technology assessment agencies, regulatory bodies, research groups, scientific societies and industry. EBM Reviews-Cochrane Methodology Register and Health Technology Assessment, Embase and MEDLINE databases (1946 to 11 May 2022). ELIGIBILITY CRITERIA: Papers proposing a framework or recommendations for extrapolating evidence for rare cancers, small populations and biomarker-defined cancers. DATA EXTRACTION AND SYNTHESIS: We extracted framework details where available and guidance for components of extrapolation. We used these components to structure and summarise recommendations. RESULTS: We identified 23 papers. One paper provided an extrapolation framework but was not cancer specific. Extrapolation recommendations addressed six distinct components: strategies for grouping cancers as the same biomarker-defined disease; analytical validation requirements of a biomarker test to use across cancer types; strategies to generate control data when a randomised concurrent control arm is infeasible; sources to inform biomarker clinical utility assessment in the absence of prospective clinical evidence; requirements for surrogate endpoints chosen for the rare cancer; and assessing and augmenting safety data in the rare cancer. CONCLUSIONS: In the absence of an established framework, our recommendations for components of extrapolation can be used to guide discussions about interpreting evidence to support extrapolation. The review can inform the development of an extrapolation framework for biomarker-targeted therapies in rare cancers.

Reimagining Perinatal Palliative Care: A Broader Role for Support in the Face of Uncertainty.

Perinatal medicine is confronted by a growing number of complex fetal conditions that can be diagnosed prenatally. The evolution of potentially life-prolonging interventions for the baby before and after birth contributes to prognostic uncertainty. For clinicians who counsel families in these circumstances, determining which ones might benefit from early palliative care referral can be challenging. We assert that all women carrying a fetus diagnosed with a life-threatening condition for which comfort-focused care at birth is one ethically reasonable option ought to be offered palliative care support prenatally, regardless of the chosen plan of care. Early palliative care support can contribute to informed decision making, enhance psychological and grief support, and provide opportunities for care planning that includes ways to respect and honor the life of the fetus or baby, however long it may be.

Adverse events in the placebo arm of maintenance therapy trials in advanced ovarian cancer: A systematic review and meta-analysis.

BACKGROUND: Maintenance treatment is standard of care for front-line (FL) and platinum-sensitive recurrent ovarian cancer (PSROC) following response to chemotherapy. Adverse events (AEs) on maintenance therapies are common and usually attributable to investigational treatments but could also be unrelated. Randomised controlled trial (RCT) with blinded placebo design is the gold standard for determining the relative differences in efficacy and AEs between treatment arms. We performed a meta-analysis to quantify AE rates in placebo arms of RCTs to determine AEs not due to investigational agents. METHODS: We performed an electronic search to identify eligible RCTs in FL and PSROC settings. Data from placebo arms were extracted and pooled using the inverse variance method to determine the risk of any AE, overall and specific grade 3 or higher (G ≥ 3) AEs, and AE-related treatment delay, reduction and discontinuation. RESULTS: We identified 13 eligible RCTs (FL, N = 8; PSROC, N = 5) with 2224 patients who received placebo (FL, N = 1541; PSROC, N = 683). The majority experienced an AE of any grade (FL, 93.0%; PSROC, 95.2%). Substantial proportions experienced G ≥ 3 AEs (FL, 14.6%; PSROC, 18.2%). In the FL setting, AEs led to treatment delay in 14.4%, dose reduction in 4.1% and discontinuation in 2.6%. Findings were similar for PSROC: 8.4%, 5.5% and 2.1%, respectively. CONCLUSIONS: AEs not due to investigational agents are common in ovarian cancer patients in maintenance therapy RCTs. Potential explanations include the nocebo effect, residual toxicities from previous treatment or underlying disease. Further research is required to identify better approaches to assessing AEs in this population.

Contributions and perspectives of Indigenous Peoples to the study of mercury in the Arctic.

Arctic Indigenous Peoples are among the most exposed humans when it comes to foodborne mercury (Hg). In response, Hg monitoring and research have been on-going in the circumpolar Arctic since about 1991; this work has been mainly possible through the involvement of Arctic Indigenous Peoples. The present overview was initially conducted in the context of a broader assessment of Hg research organized by the Arctic Monitoring and Assessment Programme. This article provides examples of Indigenous Peoples' contributions to Hg monitoring and research in the Arctic, and discusses approaches that could be used, and improved upon, when carrying out future activities. Over 40 mercury projects conducted with/by Indigenous Peoples are identified for different circumpolar regions including the U.S., Canada, Greenland, Sweden, Finland, and Russia as well as instances where Indigenous Knowledge contributed to the understanding of Hg contamination in the Arctic. Perspectives and visions of future Hg research as well as recommendations are presented. The establishment of collaborative processes and partnership/co-production approaches with scientists and Indigenous Peoples, using good communication practices and transparency in research activities, are key to the success of research and monitoring activities in the Arctic. Sustainable funding for community-driven monitoring and research programs in Arctic countries would be beneficial and assist in developing more research/monitoring capacity and would promote a more holistic approach to understanding Hg in the Arctic. These activities should be well connected to circumpolar/international initiatives to ensure broader availability of the information and uptake in policy development.

Prevalence and characteristics of frequent presenters to Auburn Hospital emergency department.

OBJECTIVES: Frequent presenters (FPs) to the ED are common and contribute to ED overcrowding. Our aim was to identify the proportion of FPs over a 12-month period and to investigate the sociodemographic, clinical and attendance characteristics of FPs. METHODS: A retrospective cohort study of adult patients (≥18 years) presenting to Auburn Hospital ED between 1 January 2018 to 31 December 2018. Patients with ≥4 presentations in 12 months were classified as FP. Multivariable logistic regression was used to assess associations between sociodemographic characteristics and FP. RESULTS: During the study period, there were 22 679 presentations to the ED from 16 624 adult patients. FPs represented 5.1% (95% confidence interval [CI] 4.8-5.5) of the total population, but 15.8% of the total ED visits. Median age of FPs was 46 years (interquartile range 29-72), 51.9% were males. Age over 65 was the strongest determinant of FP (odds ratio [OR] 2.33; 95% CI 2.01-2.72 adjusted for sex). FP was more likely for Arabic speakers compared to English speakers (OR 1.54; 95% CI 1.28-1.86 adjusted for age and sex) and least likely for Mandarin speakers (adjusted OR 0.40; 95% CI 0.27-0.59). CONCLUSIONS: FPs represent a significant proportion of ED visits, yet a small proportion of ED patients. Our findings suggest that identifying ways to provide targeted services to older FPs may reduce the overall rates. The differences between language groups and FP highlights the importance of social context and culture when developing targeted interventions.

Does Cannabidiol Have a Benefit as a Supportive Care Drug in Cancer?

OPINION STATEMENT: Cannabinoids have been purported as having a wide range of therapeutic uses although currently, there is minimal evidence to support these claims. Patients with advanced cancer experience many distressing symptoms, with some turning to medicinal cannabis to help alleviate these. Focus has fallen on cannabidiol (CBD) as a potential treatment for a variety of symptoms in advanced cancer due to the lack of psychoactive side effects and the potential molecular mechanisms of action associated with this cannabinoid. Many cannabinoid products are easily available in the community, and more countries are legalizing or allowing over the counter products. Studies show that CBD is generally well tolerated, but there are many potential drug interactions that have not been well studied. Few studies have specifically looked at the role of CBD in treating cancer symptoms, with most focusing on combination cannabinoid products. There are currently many unknowns associated with CBD, including which symptoms it might be best for, appropriate dosing, and route of administration. This is especially important in advanced cancer where patients often have significant organ dysfunction and frailty that could impact on the pharmacology of CBD. A small pilot study has shown promise for a role of CBD in the psychological symptoms associated with advanced cancer. Further research is currently underway to further clarify the role of CBD in this setting and to understand how best it might help our patients. Currently we advocate that CBD be used in supervised clinical trials, so that efficacy and adverse effects can be closely monitored.

Cost-Effectiveness of PET/CT Surveillance Schedules to Detect Distant Recurrence of Resected Stage III Melanoma.

OBJECTIVE: To estimate the cost-effectiveness of three surveillance imaging strategies using whole-body positron emission tomography (PET) with computed tomography (CT) (PET/CT) in a follow-up program for adults with resected stage III melanoma. METHODS: An analytic decision model was constructed to estimate the costs and benefits of PET/CT surveillance imaging performed 3-monthly, 6-monthly, or 12-monthly compared with no surveillance imaging. RESULTS: At 5 years, 3-monthly PET/CT surveillance imaging incurred a total cost of AUD 88,387 per patient, versus AUD 77,998 for 6-monthly, AUD 52,560 for 12-monthly imaging, and AUD 51,149 for no surveillance imaging. When compared with no surveillance imaging, 12-monthly PET/CT imaging was associated with a 4% increase in correctly diagnosed and treated distant disease; a 0.5% increase with 6-monthly imaging and 1% increase with 3-monthly imaging. The incremental cost-effectiveness ratio (ICER) of 12-monthly PET/CT surveillance imaging was AUD 34,362 for each additional distant recurrence correctly diagnosed and treated, compared with no surveillance imaging. For the outcome of cost per diagnostic error avoided, the no surveillance imaging strategy was the least costly and most effective. CONCLUSION: With the ICER for this strategy less than AUD 50,000 per unit of health benefit, the 12-monthly surveillance imaging strategy is considered good value for money.