Respiratory syncytial virus knowledge, attitudes, and perceptions among adults in the United States

Respiratory syncytial virus (RSV) is associated with considerable morbidity and mortality among older adults (aged ≥60 years) and adults with certain chronic conditions in the United States (US). Despite this burden, no previous studies have assessed the knowledge, attitudes, and perceptions (KAP) of RSV among these populations. This study evaluates RSV-related KAP among US adults at increased risk of severe RSV infection. A cross-sectional, web-based survey was administered from May to June 2022 to better understand respiratory infection- and RSV-related KAP among US adults who are at risk of severe RSV infection. The survey included ≥200 adults in each of 4 subgroups: adults aged 60-89 years, and adults aged 18-59 years with ≥1 chronic cardiovascular condition, chronic pulmonary condition, or diabetes mellitus. Survey responses were analyzed descriptively overall and by subgroup, with exploratory logistic regression modeling used to evaluate characteristics associated with RSV awareness and concern. Among the 827 survey respondents, only 43.3% had ever heard of RSV (n = 358/827). The study identified key knowledge gaps (e.g. bacterial vs. viral nature of respiratory infections, RSV seasonality, common RSV symptoms, extent to which RSV causes respiratory infections in specific patient populations). Although 33.7% of RSV-aware adults (n = 120/356) reported being worried/very worried about RSV, 67.3% (n = 241/358) rarely consider RSV as a potential cause of their cold/flu-like symptoms. Results from this study highlight important knowledge gaps related to RSV, perceived risk, and severity of RSV. Findings can be used to support the development of tailored education efforts to support RSV prevention.

Patient-reported outcomes in capmatinib-treated patients with METex14-mutated advanced NSCLC: Results from the GEOMETRY mono-1 study

INTRODUCTION

Capmatinib, a MET inhibitor, showed substantial antitumour activity with manageable side effects in patients with MET exon 14 (METex14)-mutated advanced non-small cell lung cancer (aNSCLC) in the GEOMETRY mono-1 study. We report patient-reported outcomes (PROs) from this study.

METHODS

Enrolled treatment-naïve (1L) or pre-treated (2L⁺) patients with aNSCLC with a METex14-skipping mutation received 400 mg capmatinib twice daily during 21-day treatment cycles. PROs were collected at baseline and every six weeks thereafter using EORTC QLQ-C30 global health status/quality of life (GHS/QoL), QLQ-LC13 symptoms, and EQ-5D-5L visual analogue scale (VAS) questionnaires.

RESULTS

As of 6 January 2020, 27/28 1L and 65/69 2L⁺ patients had completed PROs at baseline; compliance rates remained >70%. Cough improved early, with meaningful improvements (≥10-point change from baseline) observed throughout cycles (mean change from baseline [SD] by week 7: 1L -13.0 [39.9], 2L⁺ -8.2 [28.4]; week 43: 1L -28.2 [26.7], 2L⁺ -10.5 [27.3]). QoL, assessed by GHS/QoL and VAS, improved by week 7 in 1L and 2L⁺ patients, with improvements generally sustained over time. Median time to definitive deterioration (TTDD) in GHS/QoL was 16.6 months (95% CI: 9.7, not estimable [NE]) in 1L and 12.4 months (95% CI: 4.2, 19.4) in 2L⁺ patients. Median TTDD for dyspnoea was 19.4 months (95% CI: 12.4, NE) and 22.1 months (95% CI: 9.9, NE) for 1L and 2L⁺ patients, respectively, and NE for cough and chest pain.

CONCLUSIONS

Capmatinib was associated with clinically meaningful improvements in cough and preserved QoL, further supporting its use in patients with METex14-mutated aNSCLC.

TRIAL REGISTRATION

ClinicalTrials.gov registry number: NCT02414139.

Engaging the Asian American Community to Address Cancer Burden: Experiences and Lessons Learned

BACKGROUND

Reducing cancer health disparities in Asian Americans requires orchestrated efforts and partnerships.

OBJECTIVES

To describe the approach used by the University of Texas MD Anderson Cancer Center, HOPE Clinic, and Asian American organizations to understand and engage Houston's Asian American communities in cancer research, as well as to share lessons learned.

METHODS

The community-academic-medical partnership used community-based research principles to build the partnership, form the community advisory board, conduct a community needs assessment, and offer cancer prevention engagement and education.

RESULTS

Some lessons learned included balancing language needs with limited resources, incorporating more time and resources to conduct health research in an ethnically diverse community, and promoting awareness of research and its role in cancer prevention in Asian American communities.

CONCLUSIONS

Community-academic-medical partnerships are promising ways to engage the community, draw on combined expertise, and create research and programs that are scientifically strong and meaningful to the community.

1288. US Healthcare Provider Perspectives on the initiation of cabotegravir and rilpivirine long-acting (CAB+RPV LA) in an observational real-world study (BEYOND)

Background

CAB+RPV LA is a complete regimen for treatment of virologically suppressed people with HIV (PWH). As an injectable therapeutic administered by a healthcare provider (HCP), CAB+RPV LA may alleviate challenges with adherence to daily oral therapy and reduce fear of HIV status disclosure with oral treatment. Real world perspectives from HCPs and PWH are needed to enable successful delivery of this treatment in US healthcare settings.

Methods

BEYOND is a 2 year prospective, observational, real-world study of utilization, outcomes, and experience of PWH initiating CAB+RPV LA across 30 US sites. HCPs at participating sites (treaters, injectors, drug acquisition/reimbursement staff) completed surveys at site activation (Sep 2021-Feb 2022; with follow-up surveys planned at 6, 12, 24 months) evaluating experiences to date with implementation of CAB+RPV LA at their sites.

Results

HCPs from 24 sites responded to the initial survey (Table 1). 75% of HCPs estimated that ≥25% of their PWH are eligible for CAB+RPV LA, and 71% of sites are proactively discussing the regimen with ≥25% of PWH. The majority (79%) of treaters reported they were extremely/very positive about administering CAB+RPV LA. Over 90% of injectors reported a positive overall opinion about administering CAB+RPV LA, and 86% reported the injections were easy to administer. Most (87%) HCPs reported injection visits taking ≤45 minutes, including waiting time. Over 95% of sites have patient reminder systems; 86% will manually identify missed injections and all reported manual follow up by site staff. All sites utilizing the injection education video on the external HCP website (n=15/15) found it helpful and 94% (n=16/17) utilizing reimbursement specialists found them to be helpful. In their experience to date, most clinics reported only needing to increase coordination with the pharmacy team and add injection training to implement CAB+RPV LA. The most frequently reported benefits of implementing CAB+RPV LA by HCPs included assurance of patient adherence and patient engagement in their HIV treatment (Table 2).

Conclusion

Early real-world data from US HCPs in this study indicates interest in and anticipated uptake of CAB+RPV LA at their sites, positive overall opinion, and multiple benefits of administering the CAB+RPV LA regimen to PWH.

Disclosures

Ricky K. Hsu, MD, Gilead: Honoraria|Merck: Honoraria|ViiV: Advisor/Consultant|ViiV: Grant/Research Support|ViiV: Honoraria John Phoenix, MSN, APRN, FNP-C, Gilead Sciences: Advisor/Consultant|Gilead Sciences: Honoraria|Gilead Sciences: speaker bureau, research funding|Janssen Pharmaceutical: Advisor/Consultant|Janssen Pharmaceutical: Honoraria|Lupin Pharmaceuticals: Advisor/Consultant|Lupin Pharmaceuticals: Honoraria|Napo pharmaceutical: Honoraria|Napo pharmaceutical: speaker bureau|Scinexis: Advisor/Consultant|Scinexis: Honoraria|ViiV Healthcare: Advisor/Consultant|ViiV Healthcare: Honoraria|ViiV Healthcare: speaker bureau, clinical research funding Gary I. Sinclair, MD, ABBVIE: Grant/Research Support|Gilead: Grant/Research Support|Janssen: Advisor/Consultant|Janssen: Grant/Research Support|Janssen: Honoraria|Merck: Grant/Research Support|Thera: Grant/Research Support|Thera: Honoraria|ViiV/GSK: Advisor/Consultant|ViiV/GSK: Grant/Research Support|ViiV/GSK: Honoraria Samir K. Gupta, MD, Gilead Sciences: Advisor/Consultant|GSK/ViiV: Advisor/Consultant|GSK/ViiV: Grant/Research Support Ana Puga, MD, FAAP, AAHIVS, Care Resource: Healthcare provider (HCP)|ViiV Healthcare: Stocks/Bonds Kaitlin Nguyen, PharmD, AAHIVE, ViiV Healthcare: Stocks/Bonds Catherine K. Schubert, PharmD, ViiV Healthcare: Stocks/Bonds Deanna Merrill, PharmD, MBA, AAHIVP, ViiV Healthcare: Salaried employee|ViiV Healthcare: Stocks/Bonds David Richardson, BA, ViiV Healthcare: ViiV provided funding to RTI for the development of the study materials, the conduct of the study, and analysis & interpretation of study results. Kate Nelson, M.Ed, ViIV: ViiV provided funding to RTI for the development of the study materials, the conduct of the study, and analysis & interpretation of study results. Maria Reynolds, MStat, ViiV Healthcare: Viiv provided funding to RTI for the development of the study materials, the conduct of the study, and analysis & interpretation of study results. Laurie Zografos, BS, Viiv: ViiV provided funding to RTI for the development of the study materials, the conduct of the study, and analysis & interpretation of study results. Ashley Jean-Louis, MPH, ViiV Healthcare: (ViiV provided funding to RTI for the development of the study materials, the conduct of the study, and analysis & interpretation of study results.) Cindy Garris, MS, ViiV Healthcare: Employee|ViiV Healthcare: Stocks/Bonds.

1602 A Quality Improvement Project on The Management of Patients with Traumatic Head Injury Presenting to A District General Hospital

Introduction

Traumatic Brain Injury (TBI) is associated with morbidity and mortality. All District General Hospitals (DGH) in West Midlands liaise with Neurosurgery centres for management of these patients through a referral system (NORSe). The aim of this study was to assess outcomes in TBI following the implementation of vital interventions.

Method

A retrospective data was collected between 1/1/2019 and 1/12/2020. We included all patients admitted with traumatic brain injury over the age of 16. We accessed the data from the hospital database, clinical notes, and NORSe. A re-audit was performed following implementations of recommendations (proforma and care of elderly input). Further data were collected prospectively.

Results

Our cohort included n1=61 patients (first cycle) and n2= 29 (second cycle). The demographic age and gender were comparable in both cycles. The median time for Neurosurgery advice was 229 minutes (IQR 60-690) in the first cycle as compared to 80 minutes (IQR 40-120, P < 0.05) and the main cause for delay was inadequate information transfer. The mortality rate was 24% (5 were attributed to sepsis), as compared to 14% in the second cycle. The median length of stay (LOS) was 4 days (IQR 3-13.5) in the first cycle, which translates to a cost of £26,815 per quarter. In comparison, LOS was 3 days (IQR 2-4), which translates to the cost of bed occupancy of £12,771 and saving of £14,043 per quarter, in the second cycle.

Conclusions

The introduction of simple interventions in a DGH can help to significantly improve patient outcomes in those admitted with Traumatic brain injury.

Patient-reported outcomes in capmatinib-treated patients with METex14-mutated advanced NSCLC: Results from the phase II GEOMETRY mono-1 study

9056

Background: Capmatinib, a potent, selective MET inhibitor, showed substantial antitumor activity and manageable tolerability in patients with METex14-mutated advanced non-small cell lung cancer (aNSCLC) in the GEOMETRY mono-1 trial (NCT02414139). Patient-reported outcomes (PROs) from this study are reported here. Methods: GEOMETRY mono-1 enrolled patients ≥18 years with METex14-mutated or MET-amplified, ALK-negative and EGFR wild-type, treatment-naïve (1L) or pre-treated (2L+) aNSCLC, to receive capmatinib orally 400 mg bid during 21-day treatment cycles. Here we report results for patients with METex14 mutations. PROs (EORTC QLQ-C30, QLQ-LC13 and EQ-5D-5L) were collected at baseline (BL) and every 6 weeks (Wks) until end of treatment. Key PROs (in patients with BL and ≥1 post-BL value) included change from BL in QLQ-C30 global health status (GHS), QLQ-LC13 symptoms (cough, chest pain and dyspnea), and EQ-5D-5L visual analogue scale (VAS), with a ≥10-point change from BL considered clinically meaningful. Time to definitive deterioration (TTDD) in QLQ-LC13 symptoms (time from treatment initiation to first date of ≥10% symptom change from BL with no later reduction) was assessed using Kaplan-Meier. QLQ-LC13 symptoms over time were explored by BIRC-assessed clinical response to capmatinib. Results: By Jan 6, 2020 cut-off, median capmatinib exposure was 48.2 (4.0 117.4) Wks and 22.1 (0.4 136.0) Wks for 1L and 2L+ patients, respectively. A total of 27/28 1L patients and 65/69 2L+ patients completed PROs at BL, and completion rate remained high (mostly > 70%) through treatment cycles. Mean [SD] BL PRO scores were moderate-to-high in 1L and 2L+ patients (GHS: 64.7 [21.6] and 58.8 [21.0.]; cough: 35.9 [32.6] and 28.7 [28.2]; chest pain: 12.8 [23.2] and 17.2 [22.7]; dyspnea: 23.5 [23.4] and 22.2 [20.8]; VAS: 67.7 [20.8] and 61.9 [18.8], respectively). Overall change from BL in PROs was maintained over time. Cough improved early, with meaningful improvements observed through cycles, notably in 1L patients (mean change from BL [SD] at Wk 7: 1L -13.0 [39.9], 2L+ -8.2 [28.4]; Wk 25: 1L -15.6 [33.0], 2L+ -6.0 [31.5]; Wk 43: 1L -28.2 [26.7], 2L+ -10.5 [27.3]). Median TTDD in GHS was 16.6 months (95% CI: 9.7, NE [not estimated]) and 12.4 months (95% CI: 4.2, 19.4) in 1L and 2L+ patients, respectively. Median TTDD for cough and chest pain was NE in both 1L and 2L+ patients, and for dyspnea was 19.4 months (95% CI: 12.4, NE) and 22.1 months (95% CI: 9.9, NE), respectively. QLQ-LC13 symptoms improved at all cycles in patients achieving clinical complete response or partial response, while symptom worsening was seen in those with no clinical response. Conclusions: Capmatinib was associated with clinically meaningful improvements in cough, delayed time to lung symptom deterioration, and preserved QoL, supporting its use as a treatment option in patients with METex14-mutated aNSCLC. Clinical trial information: NCT02414139.

Long-term cancer surveillance: results from the Forteo Patient Registry Surveillance Study

The Forteo Patient Registry estimated the incidence of osteosarcoma in US patients treated with teriparatide and enrolled in the study between 2009 and 2019. No incident cases of osteosarcoma were identified among patients registered, and the crude incidence rate was 0 (95% confidence interval [CI], 0-10.2) cases per million person-years.

PURPOSE

The prospective, voluntary Forteo Patient Registry was established to estimate the incidence of osteosarcoma in patients who have received treatment with teriparatide (Forteo).

METHODS

Information on US adults prescribed teriparatide and enrolled in the Forteo Patient Registry 2009-2019 was linked with data from participating state cancer registries annually (2010-2019) to identify incident osteosarcoma cases using a standardized linkage algorithm. Teriparatide exposure was ascertained from self-reported data that included teriparatide initiation and demographics necessary to complete linkage. Osteosarcoma cases diagnosed on or after January 1, 2009, were identified by participating state cancer registries. The crude incidence rate (IR) and standardized incidence ratio (SIR) of observed cases to the expected number of cases adjusted to the background rate (3 per million person-years) and corresponding 95% CIs for the occurrence of osteosarcoma were calculated whereby the cumulative amount of person-time observed was adjusted for mortality.

RESULTS

Data for 75,247 enrolled patients (representing 361,763 cumulative person-years) were linked to each of 42 participating state cancer registries (covering 93% of the US population), which included information on 6180 cases of osteosarcoma. No matches with incident cases of osteosarcoma following registry enrollment were found. The crude IR was 0 (95% CI, 0-10.2) cases per million person-years and the SIR was 0 (95% CI, 0-3.0).

CONCLUSIONS

The ability to draw conclusions about the incidence of osteosarcoma among patients participating in the registry was limited due to the smaller than expected amount of patient follow-up time and the fact that no cases were identified.

A prospective observational study of patient-reported functioning and quality of life in advanced and metastatic breast cancer utilizing a novel mobile application

Purpose

To assess and describe patient-reported outcomes (PROs) in women with locally advanced/unresectable or metastatic breast cancer (aBC/mBC) with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR + /HER2 −) status receiving palbociclib combination therapy in a US real-world setting.

Methods

A prospective, noninterventional, multicenter longitudinal study was conducted in US patients initiating treatment with palbociclib combination therapy for HR + /HER2 − aBC/mBC. PRO data (SF-12; CES-D-10; mood; pain; fatigue; interference of aBC/mBC or its treatment on family life, social life, physical activity, energy, and productivity; overall health rating; and quality of life [QOL]) were collected via a custom-developed mobile application at daily, weekly, and cycle-based intervals. Patient medical information (demographics, clinical characteristics, treatment information, and adverse events) was collected from medical records at baseline and at the end of the 6-month follow-up period.

Results

Patients’ general health status (SF-12) remained consistent throughout treatment and was generally consistent with published norms for individuals diagnosed with cancer. The presence of depression (CES-D-10) was low and did not change substantially over time. Mean pain and fatigue scores using an 11-point numeric rating scale were low and remained stable. Patients, on average, reported neutral or positive moods. Patient-reported QOL and overall health was primarily “Good,” “Very good,” or “Excellent.” Findings were consistent regardless of patient experience with neutropenia.

Conclusions

Patients treated with palbociclib, on average, reported consistently low levels of pain and fatigue as well as good QOL and overall health that remained stable throughout the first 6 months of treatment regardless of episodes of neutropenia.

Supplementary information

The online version of this article (10.1007/s10549-020-06082-7) contains supplementary material, which is available to authorized users.

Efficacy and safety of catheter ablation for atrial fibrillation in patients with cancer

Background

Atrial fibrillation (AF) is the most common arrhythmia in patients with cancer. Management of AF in patients with cancer poses unique challenges. Long-term use of antiarrhythmic drug (AAD) therapy lacks evidence of efficacy in this population and poses risk of drug interactions. Catheter ablation is a well-established treatment modality for AAD resistant symptomatic AF and in patients with heart failure. Nevertheless, the effectiveness and safety of catheter ablation in patients with cancer is not well established.

Method

We retrospectively analyzed consecutive patients who underwent catheter ablation for AF, with either history of cancer (other than non-melanoma skin cancer) within 5-years prior or exposure to systemic anthracycline and/or thoracic radiation therapy at any time.

Results

The study included 162 patients. The mean age was 65.5 (26–84 years) years and 50% were female. Overall 133 (82%) patients had freedom from AF at 12 months following ablation. Of these 74 (54%) required post-ablation AAD, 18 (13.5%) required another ablation within the first 12 months and 9 (6.7%) required both AAD and a second ablation to maintain sinus rhythm. There were 14 adverse events (8.6%); 5 access site and 4 non-access site bleeding, 2 strokes, 2 cardiac tamponade and 1 pulmonary vein stenosis with ≈1% serious complications.

Conclusion

The success of catheter ablation for AF and the incidence of procedure related complications in patients with a history of recent cancer or prior exposure to cardiotoxic therapies are similar to that reported in patients without a history of cancer and hence if needed, it should be considered in select patients.

Funding Acknowledgement

Type of funding source: Private hospital(s). Main funding source(s): Dr. S Ganatra is supported by Lahey Physician Research Stipend Program.

Validation of cardiovascular outcomes and risk factors in the Clinical Practice Research Datalink in the United Kingdom

Purpose

Strategies to identify and validate acute myocardial infarction (AMI) and stroke in primary‐care electronic records may impact effect measures, but to an unknown extent. Additionally, the validity of cardiovascular risk factors that could act as confounders in studies on those endpoints has not been thoroughly assessed in the United Kingdom Clinical Practice Research Datalink's (CPRD's) GOLD database. We explored the validity of algorithms to identify cardiovascular outcomes and risk factors and evaluated different outcome‐identification strategies using these algorithms for estimation of adjusted incidence rate ratios (IRRs).

Methods

First, we identified AMI, stroke, smoking, obesity, and menopausal status in a cohort treated for overactive bladder by applying computerized algorithms to primary care medical records (2004–2012). We validated these cardiovascular outcomes and risk factors with physician questionnaires (gold standard for this analysis). Second, we estimated IRRs for AMI and stroke using algorithm–identified and questionnaire–confirmed cases, comparing these with IRRs from cases identified through linkage with hospitalization/mortality data (best estimate).

Results

For AMI, the algorithm's positive predictive value (PPV) was >90%. Initial algorithms for stroke performed less well because of inclusion of codes for prevalent stroke; algorithm refinement increased PPV to 80% but decreased sensitivity by 20%. Algorithms for smoking and obesity were considered valid. IRRs based on questionnaire‐confirmed cases only were closer to IRRs estimated from hospitalization/mortality data than IRRs from algorithm‐identified cases.

Conclusions

AMI, stroke, smoking, obesity, and postmenopausal status can be accurately identified in CPRD. Physician questionnaire–validated AMI and stroke cases yield IRRs closest to the best estimate.

A-35 On-Field Dizziness and Timing of Referral to Vestibular Therapy Following Adolescent Sports-Related Concussion: Initial Findings

Objective

To examine if adolescent patients who experienced on-field dizziness immediately following sports-related concussion (SRC) and were referred to vestibular therapy (VT) in 7–9 days returned to play faster when compared to referrals made > 10 days.

Method

Registry data for an outpatient clinic specializing in adolescent SRC was analyzed. Of the 85 adolescent patients included, 67 (79%) experienced dizziness immediately following injury; 36 (54%) of which were referred to VT. Mean age at time of injury was 15.3 years; 61.1% were male (n = 22); most were injured while participating in football (38.9%), soccer (16.7%), or wrestling (13.9%). Days to initial VT evaluation from time of injury and days from VT to clearance from concussion protocol were analyzed using a Poisson regression model; age and sex were controlled.

Results

Patients referred to VT 7–9 days post-injury returned to play 16 ± 13.4 days earlier (20.7 ± 18.6 days; p < .0001) than patients who received VT 10–20 days post SRC (36.7 days±32). While non-significant, individuals referred to VT > 21 days post-injury returned to play 6 days later than those referred < 10 days (26.3 ± 32.9; p = .14).

Conclusions

Appropriate and timely referrals to VT following the presence of on-field dizziness after SRC may play an integral role in recovery, although more research in this area is needed. Initial findings suggest that when determining optimal time frame for referral to VT, 7–9 days post-injury may be most beneficial for adolescents following SRC.

Rapid, complete and sustained tumour response to the TRK inhibitor larotrectinib in an infant with recurrent, chemotherapy-refractory infantile fibrosarcoma carrying the characteristic ETV6-NTRK3 gene fusion

BACKGROUND

The ETV6-NTRK3 gene fusion is present in the majority of cases of infantile fibrosarcoma (IFS) and acts as a potent oncogenic driver. We report the very rapid, complete, and sustained response of an advanced, chemotherapy-refractory, recurrent IFS to targeted treatment with the oral tropomyosin receptor kinase (TRK) inhibitor larotrectinib.

PATIENT AND METHODS

A male infant born with a large congenital IFS of the tongue had the tumour surgically resected at age 4 days. Within 2 months, he developed extensive lymph node recurrence that progressed during two cycles of vincristine-doxorubicin-cyclophosphamide chemotherapy. At screening, a large right cervical mass was clinically visible. Magnetic resonance imaging (MRI) revealed bilateral cervical and axillary lymph node involvement as well as infiltration of the floor of the mouth. The largest lesion measured 5.5×4.5×4.4 cm (ca. 55 cm3). The patient started outpatient oral larotrectinib at 20 mg/kg twice daily at age 3.5 months.

RESULTS

After 4 days on treatment, the parents noted that the index tumour was visibly smaller and softer. The rapid tumour regression continued over the following weeks. On day 56 of treatment, the first scheduled control MRI showed the target lesion had shrunk to 1.2×1.2×0.8 cm (ca. 0.6 cm3), corresponding to a complete response according to the Response Evaluation Criteria In Solid Tumors version 1.1. This response was maintained over subsequent follow-up visits, and on day 112 at the second control MRI the target lymph node was completely normal. At last follow-up, the disease remained in complete remission after 16 months on larotrectinib, with negligible toxicity and no safety concerns.

CONCLUSION(S)

Selective TRK inhibition by larotrectinib offers a novel, highly specific and highly effective therapeutic option for IFS carrying the characteristic ETV6-NTRK3 gene fusion. Its use should be considered when surgery is not feasible. (NCT02637687).

The effect of neutropenia on patient-reported functioning and quality of life (QOL) among palbociclib participants of the MADELINE study

1064

Background: MADELINE is an observational, multicenter study of women with HR+/HER2- advanced or metastatic breast cancer who were followed for 6 months to evaluate patient reported QOL after initiating palbociclib combination therapy or other approved treatment in the US. A novel mobile application was developed to capture PROs for QOL at daily, weekly, monthly/cycle-based intervals for up to 6 months. QOL measures were evaluated to determine if palbociclib-treated patients experiencing episodes of neutropenia had associated decreases in QOL compared to patients without episodes of neutropenia. Methods: Patients completed the SF-12 and CES-D-10 at baseline and each cycle. Change from baseline was assessed using mean scores and mixed-effects models. Daily pain and fatigue severity were measured on an 11-point scale (0-10, 10 being worst possible pain/fatigue) and averaged to create weekly scores. Patients indicated weekly how breast cancer or its treatment interfered with family/social life, productivity, physical activity and energy on a 5-point scales (from not at all to a great deal). Demographic and clinical data including adverse events were recorded in an eCRF. Results: 25 sites contributed 139 patients (median [range] age 60 [34, 82]; white: 83%; ECOG 0-1: 87%). During the 6-month follow up period, 45% of patients experienced ≥1 neutropenia event (grade 1-4: 17%, 27%, 24%, 2%) and 11% had an event resulting in a dose change. Least-square (LS) mean change from baseline to end of study for the SF-12 Physical/Mental Component summaries (PCS/MCS) and the CES-D-10 showed no association between neutropenia and decreased QOL. Daily pain/fatigue was relatively stable for those with neutropenia (cycle 1, week 1: 2.8 [1.95] and 1.8 [0.95]; cycle 6, week 1: 2.4 [1.95] and 2.3 [1.59]) and those without (cycle 1, week 1: 2.2 [2.46] and 2.8 [2.39]; cycle 6, week 1: 1.6 [2.29] and 2.4 [2.22]). There was no significant change for impact of breast cancer or treatment across cycles. Conclusions: Patients with neutropenia did not experience decreased QOL compared to patients without neutropenia nor did patients as a whole experience numerically or clinically meaningful decrease in QOL throughout the follow up period. Daily PROs collected suggest a low level of pain/fatigue that did not change substantially over time. [Table: see text]

Skull fractures in forensic putrefied/skeletonised cases: The challenge of estimating the post-traumatic interval

The objective of our study was to assess the reliability of the estimation of posttraumatic survival time (PTST) in forensic cases based on microCT and histology of putrefied/dry bone samples with comparison of initial macroscopic fracture classification performed during autopsy. Macroscopic morphological patterns of bone fracture are routinely used in forensic pathology and anthropology to distinguish between antemortem, perimortem and postmortem injuries. Based on macroscopic and microscopic analysis of six craniofacial fractures, our study results illustrate the need to complete macroscopical findings and initial fracture classification with microscopic analysis to avoid any inaccuracy. MicroCT has become a powerful technique to identify early bone healing signs but histology remains the gold standard to estimate the PTST and determine vital fracture based on hemorrhage marker. Raman microspectroscopy can identify a blood clot in the fracture line.

Abstract P1-19-41: Relationship between depression status and daily and weekly mood in the MADELINE study

Background: MADELINE is an observational, multicenter study of women in the United States with advanced/metastatic breast cancer (ABC/MBC) receiving palbociclib in combination with either an aromatase inhibitor (AI) as initial endocrine therapy or fulvestrant after progression on prior endocrine therapy. A novel mobile application was used to collect real-time patient-reported outcome (PRO) data to assess patient functioning and quality of life through daily, weekly, and monthly questionnaires for 6 months.

Methods: Patients completed the Center for Epidemiologic Studies Depression Scale (CES-D-10) at each cycle; total scores range from 0 to 30, where 10 or more is considered to indicate depression. Based on CES-D-10 scores patients’ depression status could vary cycle-to-cycle. Data on patient’s mood was collected using a daily seven-level mood rating (“very sad” to “most happy”) and a weekly five-level question on breast cancer or its treatment’s negative effect on mood or emotions (“not at all” to “a great deal”). A descriptive analysis examining the relationship between depression (CES-D-10), and the two mood questions was conducted among patients with a completed baseline electronic case report form and relevant mobile app data as of May 1, 2019.

Results: Twenty-three sites contributed 137 patients (median [range] age 60 [34, 82]; white: 84%; ECOG 0-1: 87%; initiated palbociclib plus AI at enrollment: 62%). At cycle 1, 48 patients were classified as without depression (score <10) and 33 patients with depression (score >10). During week 1 of cycle 1, the average percentage of days where patients without depression reported a mood of “Neutral” was 37.8%, “Content” was 34.8%, and “Happy” was 22.9% compared to patients with depression reporting 55.2% for “Neutral”, 21.6% for “Content”, and 2.6% for “Happy”. In the same reporting period, 56% (15/27), 19% (5/27), and 4% (1/27) of patients with depression indicated breast cancer or its treatment had negatively impacted their mood or emotions “moderately”, “quite a bit”, or “a great deal” respectively whereas 13% (5/38) of patients without depression indicated it negatively impacted their mood or emotions “moderately” and 0% indicated either “quite a bit” or “a great deal”. Results were relatively similar across the cycles overall and for patients that initiated either palbociclib plus AI or palbociclib plus fulvestrant.

Conclusions: The majority of patients in the MADELINE study did not report symptoms indicating depression based on the CES-D-10 at the beginning of treatment and across cycles. Results suggest that the mood and emotions of patients with depression was more negatively impacted by breast cancer or its treatment compared with patients without depression.

Citation Format: David Richardson, Lin Zhan, Maria Reynolds, Dawn Odom, Lynn McRoy, Debanjali Mitra, Jeffrey Hargis. Relationship between depression status and daily and weekly mood in the MADELINE study [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-41.

Abstract P1-19-35: Trends in daily mood, pain, and fatigue among participants in the MADELINE study

Background: MADELINE is an observational, multicenter study of women in the United States with metastatic breast cancer (MBC) receiving palbociclib in combination with an aromatase inhibitor (AI) as initial endocrine therapy, or fulvestrant after progression on prior endocrine therapy. A novel mobile application is used to collect real-time patient-reported outcome (PRO) data to assess patient functioning and quality of life through daily, weekly, and monthly questionnaires for 6 months.

Methods: An interim analysis of select PRO data was conducted among completed and ongoing patients with a minimum of baseline mobile app and eCRF data as of May 1, 2019. PROs analyzed included daily assessments of seven-level mood rating (very sad to most happy), pain and fatigue severity measured using an 11-point (0 to 10 with 10 being the worst possible pain or fatigue) numeric rating scale (NRS), and pain location. Analyses were descriptive and daily data were averaged to create weekly scores.

Results: Twenty-three sites contributed 137 patients (mean [± standard deviation] age 59.7 ± 11.74; white: 84%; ECOG 0-1: 87%; initiated palbociclib plus AI at enrollment: 62%). At the start of cycle 1, the average percentage of days where patients reported a mood of “Neutral” was 44.5%, followed by “Content” with 26.5%; results were relatively stable across the study. The average daily level of pain was 2.3 (2.32) on the NRS during cycle 1, week 1 with no substantial numerical changes across the study [cycle 6, week 4: mean± standard deviation 2.0 (2.13)]. Pain was indicated throughout the body but reported more frequently in the lower body, legs and chest. The average daily fatigue severity on the NRS during the following time points were [mean ± standard deviation]: cycle 1, week 1: 2.8 (2.25); cycle 3, week 1: 2.5 (2.31); and cycle 6, week 1: 2.3 (1.91). Results were relatively similar for patients that initiated either palbociclib plus AI or palbociclib plus fulvestrant. Average daily pain and fatigue scores for week 1 by cycle are shown in the table.

Conclusions: Daily reported PRO collected in the MADELINE study suggest a low level of pain and fatigue that does not change substantially over time. The most commonly reported mood ratings among patients were neutral or content.

Average daily pain and fatigue scores by cyclePalbociclib + AI(N = 85)Palbociclib + Fulvestrant(N = 52)Overall(N = 137)nMean (SD) scorenMean (SD) scorenMean (SD) scoreCycle 1/Week 1Pain842.4 (2.41)462.0 (2.16)1302.3 (2.32)Fatigue842.7 (2.31)462.9 (2.16)1302.8 (2.25)Cycle 2/Week 1Pain691.9 (2.15)411.7 (2.09)1101.8 (2.12)Fatigue692.4 (2.34)412.6 (2.37)1102.5 (2.34)Cycle 3/Week 1Pain621.9 (2.18)341.4 (1.79)961.7 (2.05)Fatigue622.6 (2.33)352.3 (2.28)972.5 (2.31)Cycle 4/Week 1Pain562.1 (2.23)271.8 (2.45)832.0 (2.29)Fatigue562.6 (2.45)272.3 (2.35)832.5 (2.41)Cycle 5/Week 1Pain491.7 (1.89)211.5 (1.78)701.7 (1.85)Fatigue492.4 (2.19)212.1 (2.03)702.3 (2.13)Cycle 6/Week 1Pain381.7 (1.97)151.8 (2.17)531.7 (2.01)Fatigue382.3 (1.89)152.6 (2.00)532.3 (1.91)

Citation Format: David Richardson, Lin Zhan, Maria Reynolds, Kelly Hollis, Lynn McRoy, Debanjali Mitra, Reshma Mahtani. Trends in daily mood, pain, and fatigue among participants in the MADELINE study [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-35.

Patient Perceptions of Unmet Medical Need in Rheumatoid Arthritis: A Cross-Sectional Survey in the USA

INTRODUCTION

Many rheumatoid arthritis (RA) patients do not achieve their treatment goals and experience symptoms that affect psychosocial outcomes and daily activities. This study aimed to identify and quantify the unmet needs perceived by US patients with RA currently taking a disease-modifying antirheumatic drug (DMARD).

METHODS

A cross-sectional, web-based survey was conducted with RA patients recruited through CreakyJoints, an online patient support community, and ArthritisPower®, an online patient research registry, from December 2017 to January 2018. Participant patients were aged ≥ 21 years, failed ≥ 1 DMARDs, and were receiving their current DMARD(s) for ≥ 6 months; they answered 50 questions about treatment history, RA symptoms, and flares and completed the Rheumatoid Arthritis Impact of Disease (RAID) questionnaire and the Treatment Satisfaction Questionnaire for Medication (TSQM). Treatment satisfaction was defined by a TSQM global satisfaction score ≥ 80.

RESULTS

Of 415 patients screened, 258 (62%) were eligible and completed the survey; 87% were women, and 87% white, with mean (SD) age of 54.5 (11.4) years. A total of 232 patients (90%) had current or past biologic DMARD (bDMARD) use, with 67% currently on a bDMARD, 65% on ≥ 1 conventional synthetic DMARD, and 40% on methotrexate. Forty-three percent of patients reported daily/almost daily use of prescription pain medications, and 44% reported a current flare. Mean (SD) TSQM scores were 59 [20] for effectiveness, 59 [26] for side effects, 72 [18] for convenience, and 65 [21] for global satisfaction. The mean (SD) RAID overall score was 5.1 (2.0) on a 0-10 scale. Only 26% (67 patients) were satisfied with their RA treatment. Patients not satisfied with treatment reported higher RAID scores overall and by domain, and approximately half reported a current flare.

CONCLUSIONS

Results from this real-world survey suggest that three-fourths of RA patients are not satisfied with treatments, which include bDMARDs. Patients continued to experience bothersome symptoms that impacted their daily activities and life. There remains a need for improved disease management among currently treated RA patients.

FUNDING

Eli Lilly and Company (Indianapolis, IN, USA).

Examining the relationship between obesity and mental health outcomes among individuals admitted to a level I trauma centre

The increased incidence of obesity in the general population translates into clinicians caring for an increased number of trauma patients with obesity. Previous research has documented the unique anatomical and physiological challenges that clinicians face when caring for trauma patients with obesity; however, little is known about psychological challenges that trauma patients with obesity may also experience in the months following injury. The aim of this study is to determine the relationship between obesity and (i) mental health, (ii) demographic and injury-related variables and (iii) quality-of-life outcomes among trauma patients between hospitalization and 3-months post-injury. This is a prospective, longitudinal study conducted between March 2012 and May 2014 at a single, level I trauma centre in the southwest United States. Inclusion criteria for this convenience sample consisted of patients who were admitted to the trauma or orthopaedic trauma service ≥24 h, medically stable, spoke English or Spanish and ≥18 years of age. In total, 455 eligible patients were consented and enrolled; 343 (70.87%) completed 3-month follow-up. The objective of this study is to investigate the relationship between obesity and mental health among trauma patients in the months following injury. Demographic and injury-related data were also collected; patients' height and weight were used to determine body mass index. Health outcomes were assessed during initial hospitalization and at 3-month follow-up and included depression, post-traumatic stress symptoms, pain and return to work. Prior to data collection, it was hypothesized that obesity would have a negative effect on mental health outcomes among patients 3 months post-injury. The final sample consisted of 343 participants; average age was 46.4 ± 17.3 years; majority male (n = 213, 63%) and Caucasian (n = 231, 69%). Patients with obesity had higher odds of screening positive for depression (odds ratio [OR] = 2.36, P = 0.02) and overweight patients had lower odds of returning to work (OR = 0.31, P = 0.01) 3 months post-injury compared to patients of normal weight (65% vs. 40%). No other significant differences were found. Results of the current study are novel in that they identify psychological challenges that overweight and trauma patients with obesity may experience. These results demonstrate the need for mental health professionals to be involved in follow-up care to extending in the months following injury.

Monte Carlo determination of k Q and k Qmsr values for the exradin A26 ionisation chamber for the Varian TrueBeam

We have calculated conversion factors, k _Q for the A26 micro ionisation chamber along with machine specific reference beam quality factors, k _Qmsr, for a number of field sizes and beam qualities for the Varian TrueBeam accelerator. The A12 ionisation chamber was simulated alongside the A26, so as to validate against known literature values. Both ionisation chambers were modelled from manufacturer data sheets and schematics. The egs_chamber Monte Carlo user code was used to simulate each absorbed dose relevant to the beam quality conversion factors k _Q and k _Qmsr. Tabulated spectra for beam energies of 4 through 25 MV were used in the k _Q calculations for both investigated chambers. Varian TrueBeam phase space files for 6 MV flattened as well as 6 and 10 MV unflattened beams were used in the simulations of the A26 chamber in field sizes from 2  ×  2 cm square to 20  ×  20 cm square in order to determine k _Qmsr values. The PDD(10)x  values of the tabulated spectra were found to be within variation between studies, with an average deviance of 0.4% from one prior study. The simulated A12 k _Q values matched the accepted literature values with an average variation of  <0.1%. The A26 k _Q values match the manufacturer provided values to within 0.5%. For all investigated field sizes the k _Qmsr values are within 0.006 of unity. There is no published data for this chamber for a direct comparison, but there is similarity between these results and results from other chambers regularly used in similar circumstances. Furthermore, the agreement of the simulated k _Q values to knowns, and the agreement of the PDD(10)x  factors would suggest the correctness and accuracy of the study.

Assessing the quality, reliability and readability of online health information regarding systemic lupus erythematosus

Introduction Systemic lupus erythematosus (SLE) has complex pathophysiology and treatments, and patients often use the internet to better understand their condition. This report systematically assesses the quality, reliability and readability of online information. Methods The search term 'systemic lupus erythematosus' was used with Google™, Bing™ and Yahoo™ search engines sequentially. The first 25 websites returned ('hits') for each search engine (total 75 websites) were compiled. The search terms 'SLE' and 'lupus' were used in separate Google searches to assess for commonality. After removal of excluded hits, websites were assessed using the DISCERN instrument, Journal of the American Medical Association benchmarks and Gunning Fog Index for quality, reliability and readability and presence of 'Health on the Net Code' (HoN) standardisation recorded. Results There was a large degree of commonality among hits from the three different search engines using the search term 'systemic lupus erythematosus', as well as hits returned for the three different search terms using Google. The mean DISCERN score was 47.7 (SD 13.2) for 'systemic lupus erythematosus', 46.4 (SD 14.2) for 'SLE' and 45.2 (SD 10.1) for 'lupus', with no statistically significant difference. The mean number of JAMA benchmarks (maximum four) present for the 'systemic lupus erythematosus', 'SLE' and 'lupus' searches was 1.3 (SD 1.2), 1.4 (SD 1.3) and 1.2 (SD 1.0), respectively, with no statistically significance difference. The average readability of hits for the three different search terms was 9.3 (SD 3.4), 10.0 (SD 3.1) and 11.1 (SD 2.7), with no statistically significant difference. Conclusion There was a large degree of commonality of hits among the different search engines and the utilised search terms but they are not synonymous. Regardless of search term, the overall quality of websites was fair, whilst reliability was poor. Websites appearing higher in searches did not score better. Presence of the HoN did not represent better quality. Readability was higher than recommended for near-universal understanding. There was no difference in quality, reliability or readability of websites using the search terms 'systemic lupus erythematosus', 'SLE' or 'lupus', with some high-scoring websites appearing in only one search term result. This study reminds clinicians to direct patients to high-quality websites rather than rely on search engines.

Angioedema in chronic spontaneous urticaria is underdiagnosed and has a substantial impact: Analyses from ASSURE-CSU

Background

ASSURE‐CSU revealed differences in physician and patient reporting of angioedema. This post hoc analysis was conducted to evaluate the actual rate of angioedema in the study population and explore differences between patients with and without angioedema.

Methods

This international observational study assessed 673 patients with inadequately controlled chronic spontaneous urticaria (CSU). Physicians abstracted angioedema data from medical records, which were compared with patient‐reported data. Patients in the Yes‐angioedema category had angioedema reported in the medical record and a patient‐reported source. For those in the No‐angioedema category, angioedema was reported in neither the medical record nor a patient‐reported source. Those in the Misaligned category had angioedema reported in only one source. Statistical comparisons between Yes‐angioedema and No‐angioedema categories were conducted for measures of CSU activity, health‐related quality of life (HRQoL), productivity and healthcare resource utilization (HCRU). Regression analyses explored the relationship between Dermatology Life Quality Index (DLQI) score and angioedema, adjusting for important covariates.

Results

Among evaluable patients, 259 (40.3%), 173 (26.9%) and 211 (32.8%) were in the Yes‐angioedema, No‐angioedema and Misaligned category, respectively. CSU activity and impact on HRQoL, productivity, and HCRU was greater for Yes‐angioedema patients than No‐angioedema patients. After covariate adjustment, mean DLQI score was significantly higher (indicating worse HRQoL) for patients with angioedema versus no angioedema (9.88 vs 7.27, P < .001). The Misaligned category had similar results with Yes‐angioedema on all outcomes.

Conclusions

Angioedema in CSU seems to be under‐reported but has significant negative impacts on HRQoL, daily activities, HCRU and work compared with no angioedema.

Screening and treatment for short cervical length in pregnancy: a physician survey in the United States

PURPOSE

To evaluate how physicians in the United States (US) screen for, define, and treat a short cervix to prevent preterm birth.

METHODS

This was a cross-sectional, web-based survey of 500 physicians treating pregnant patients with a short cervix in the US. Respondents' geographic region was monitored to ensure balance across the nine US Census divisions.

RESULTS

Respondents were predominantly obstetrician/gynecologists (86%, 429/500; mean age 49 years). Physicians reported that a median of 90% of their pregnant patients undergo cervical length screening; 81% (407/500) use transvaginal ultrasound. Physicians consult multiple evidence sources to inform their patient care, most commonly clinical guidelines (83%; 413/500) and published research (70%; 349/500). Most physicians (98%; 490/500) reported treating pregnant patients with a short cervix; 95% (474/500) use synthetic and/or natural progestogen, alone or in combination with other treatment modalities. If reimbursement was not a concern, 47% of physicians (230/500) would choose vaginal progesterone as their preferred treatment to prevent preterm birth in all patients with a short cervix, and 45% (218/500) would choose a synthetic progestogen.

CONCLUSION

US guidelines recommend transvaginal ultrasound for cervical length screening; 81% of physicians in this study reported using this method. Most physicians surveyed use progestogens to treat a short cervix, with approximately half choosing a synthetic progestin (45%) and half choosing natural progesterone (47%) as their preferred treatment, despite national guidelines recommending only vaginal natural progesterone for this indication. Additional physician education is required to implement current and best practices.

Indications for delivery in pre-eclampsia

OBJECTIVE

Examine the frequency with which the most accepted indicators for delivery in pre-eclampsia are used in a population with predominantly late-onset (birth > 32 weeks) pre-eclampsia (PE).

METHODS

Retrospective cohort study using the St George Public Hospital (SGH) Hypertension in Pregnancy database. Demographic, pregnancy, and outcome details were extracted and verified by comparison with data collection sheets.

RESULTS

From 2001 to 2013, 908 women (970 babies) with PE were included, of which a subgroup of 303 women (33%) had clearly delineated delivery triggers available. This subgroup of women had similar demographic and outcome characteristics to the total PE population. In this group, the most common maternal trigger for delivery apart from gestational age 37+ weeks was difficult to control/severe hypertension (114 cases, 38%) and the most common fetal trigger intrauterine growth restriction (IUGR: 14 cases, 4%). 78 (35%) of term women had no specific delivery trigger other than gestation. A primary maternal trigger and/or associated complication was slightly more common in those delivering <37 weeks vs 37+ weeks (52 vs 38%, p = .03), while a fetal or combined maternal/fetal complication was over four times more common in preterm women (25 vs 6%, p < .001).

CONCLUSION

In our population of predominantly late-onset PE, maternal triggers for delivery (predominantly severe hypertension) far outweigh fetal triggers (predominantly IUGR). Fetal and mixed indicators for delivery were relatively more common in women delivering preterm, possibly reflecting the severity of placental dysfunction in this subgroup.

Technical Note: Response measurement for select radiation detectors in magnetic fields

PURPOSE

Dose response to applied magnetic fields for ion chambers and solid state detectors has been investigated previously for the anticipated use in linear accelerator-magnetic resonance devices. In this investigation, the authors present the measured response of selected radiation detectors when the magnetic field is applied in the same direction as the radiation beam, i.e., a longitudinal magnetic field, to verify previous simulation only data.

METHODS

The dose response of a PR06C ion chamber, PTW60003 diamond detector, and IBA PFD diode detector is measured in a longitudinal magnetic field. The detectors are irradiated with buildup caps and their long axes either parallel or perpendicular to the incident photon beam. In each case, the magnetic field dose response is reported as the ratio of detector signals with to that without an applied longitudinal magnetic field. The magnetic field dose response for each unique orientation as a function of magnetic field strength was then compared to the previous simulation only studies.

RESULTS

The measured dose response of each detector in longitudinal magnetic fields shows no discernable response up to near 0.21 T. This result was expected and matches the previously published simulation only results, showing no appreciable dose response with magnetic field.

CONCLUSIONS

Low field longitudinal magnetic fields have been shown to have little or no effect on the dose response of the detectors investigated and further lend credibility to previous simulation only studies.

Assessing United States Patient and Dermatologist Experiences with Severe Chronic Hand Eczema

OBJECTIVE

Patients with severe chronic hand eczema often have persistent symptoms that interfere with daily activities, social functioning, and employment. Many patients are refractory to topical corticosteroids. This survey-based study was performed to characterize treatment experiences, impact on productivity, and quality of life of patients with severe chronic hand eczema; understand dermatologists' severe chronic hand eczema treatment patterns.

DESIGN

A web-based survey in the United States queried pre-identified patients with severe chronic hand eczema regarding symptoms, treatment history, quality of life, work productivity, treatment satisfaction, and healthcare utilization. In a separate survey, dermatologists were asked about treatment patterns and satisfaction with currently available therapies.

RESULTS

The most commonly reported symptoms currently experienced by patients (n=163) were dryness/flaking (81%), itchiness (75%), and cracking/tearing of the skin (71%). Over the last three months, 84 percent of patients with severe chronic hand eczema self-reported using topical steroids, and 30 percent used systemic corticosteroids or retinoids. Approximately 30 percent reported impairment while working and productivity loss. Patient quality of life was negatively impacted. Dermatologists (n=125) reported most often treating severe chronic hand eczema with topical corticosteroids (99%), followed by topical immunomodulators (71%) and systemic treatments (70%). Only two percent were very satisfied with currently available products.

CONCLUSION

Patients with severe chronic hand eczema experience symptoms that negatively impact work productivity and quality of life. Few dermatologists are very satisfied with currently available severe chronic hand eczema treatment options.

Dose response of selected solid state detectors in applied homogeneous transverse and longitudinal magnetic fields

PURPOSE

MR-Linac devices under development worldwide will require standard calibration, commissioning, and quality assurance. Solid state radiation detectors are often used for dose profiles and percent depth dose measurements. The dose response of selected solid state detectors is therefore evaluated in varying transverse and longitudinal magnetic fields for this purpose.

METHODS

The Monte Carlo code PENELOPE was used to model irradiation of a PTW 60003 diamond detector and IBA PFD diode detector in the presence of a magnetic field. The field itself was varied in strength, and oriented both transversely and longitudinally with respect to the incident photon beam. The long axis of the detectors was oriented either parallel or perpendicular to the photon beam. The dose to the active volume of each detector in air was scored, and its ratio to dose with zero magnetic field strength was determined as the "dose response" in magnetic field. Measurements at low fields for both detectors in transverse magnetic fields were taken to evaluate the accuracy of the simulations. Additional simulations were performed in a water phantom to obtain few representative points for beam profile and percent depth dose measurements.

RESULTS

Simulations show significant dose response as a function of magnetic field in transverse field geometries. This response can be near 20% at 1.5 T, and it is highly dependent on the detectors' relative orientation to the magnetic field, the energy of the photon beam, and detector composition. Measurements at low transverse magnetic fields verify the simulations for both detectors in their relative orientations to radiation beam. Longitudinal magnetic fields, in contrast, show little dose response, rising slowly with magnetic field, and reaching 0.5%-1% at 1.5 T regardless of detector orientation. Water tank and in air simulation results were the same within simulation uncertainty where lateral electronic equilibrium is present and expectedly differed at the beam edge in transverse field orientations only. Due to the difference in design, the two detectors behaved differently.

CONCLUSIONS

When transverse magnetic fields are present, great care must be taken when using diamond or diode detectors. Dose response varies with relative detector orientation, magnetic field strength, and between detectors. This response can be considerable (∼20% for both detectors). Both detectors in longitudinal fields exhibit little to no dose response as a function of magnetic field. Water tank simulations seem to suggest that the diode detector is better suited to general beam commissioning, and each detector must be investigated separately.