Nova Scotia Cancer Centre

BackgroundAccurate Hounsfield units (HU) are critical for dose calculation and anatomical visualization, but are often affected by dental artifacts in head and neck (H&N) cancer patients. The HyperSight cone‐beam computed tomography (CBCT) platform provides improved image quality over previous CBCT platforms and offers metal artifact reduction (iCBCT MAR) reconstruction.PurposeThis study evaluates the quality of HyperSight CBCT images compared to current clinical standards: TrueBeam CBCT for image guidance and fan‐beam CT (FBCT) from a CT simulator for treatment planning, using images captured during H&N cancer treatment.MethodsImages for 30 H&N cancer patients were acquired on a HyperSight CBCT, conventional TrueBeam and FBCT, with 24 patients exhibiting metal dental artifacts. The HyperSight images were reconstructed using iCBCT MAR and iterative (iCBCT Acuros) algorithms. The four image sets were rigidly registered and compared using the artifact index (AI) measured in the oral cavity and the percentile range (PR) measured in the oral cavity, brain, brainstem and eyes to assess image non‐uniformity. The HU accuracy was calculated relative to FBCT (baseline) for soft tissues (oral cavity, brainstem, submandibular and parotid glands), and bone (mandible). The contrast relative to baseline was evaluated between the oral cavity and nearby structures. Image‐based metrics were computed relative to FBCT including structural similarity index measure (SSIM), mean‐square error (MSE) and peak signal‐to‐noise ratio (PSNR).ResultsThe HyperSight iCBCT MAR images showed a significant reduction in AI values compared to the other images (p < 0.0004), but higher PR values indicating decreased HU uniformity compared to HyperSight iCBCT Acuros and FBCT (p < 0.0002). The soft‐tissue HU and contrast values were significantly closer to baseline in both HyperSight images compared to TrueBeam (HU: p < 0.001, contrast: p < 0.001). For soft‐tissue the HU mean absolute deviation (MAD) from baseline was 16 ± 10 HU for HyperSight iCBCT Acuros, 15 ± 10 HU for HyperSight iCBCT MAR, and 35 ± 22 HU for TrueBeam. For bone, the HU MAD from baseline was 153 ± 233 HU, 185 ± 268 HU, and 214 ± 212 HU, respectively. The HyperSight iCBCT Acuros algorithm achieved significantly superior SSIM, MSE, and PSNR metrics compared to TrueBeam and HyperSight iCBCT MAR in regions with large amounts of bone and air.ConclusionsHyperSight iCBCT MAR significantly reduced artifacts compared to HyperSight iCBCT Acuros, TrueBeam and FBCT, making it particularly beneficial for patients with metal implants. Both HyperSight reconstructions demonstrated improved soft‐tissue HU accuracy and contrast compared to TrueBeam, however the iCBCT Acuros algorithm may be preferred when metal‐induced artifacts are not a concern. These results support the suitability of HyperSight images in adaptive treatment workflows requiring accurate image quality, even with severe metal artifacts.

Staphylococcus aureus (SA) screening and decolonization is a guideline-recommended treatment for the prevention of surgical site infections in cardiac surgery. This study aimed to formally assess the barriers and facilitators associated with its implementation. Targeted SA screening and decolonization started at our institution in November 2022. To assess barriers and facilitators to implementation, we conducted focus group interviews informed by the Consolidated Framework for Implementation Research at approximately 6 months after initiation of the intervention. We also regularly collected quantitative data on missed screening and/or decolonization to address gaps in uptake. This was reviewed at 6-month and 1-year time points. Adjustments to implementation were regularly made to address barriers. At 1 year, 563 nonurgent inpatients and 232 outpatients were consulted to cardiac surgery. Ninety-five percent of the inpatients and 91% of the outpatients considered for cardiac surgery were screened appropriately. Of the patients accepted for cardiac surgery, 50% of positive inpatients underwent decolonization in the first 6 months prior to focus groups compared to 67% in the subsequent 6 months. For outpatients, 77% were decolonized in the first 6 months, compared to 79% in the subsequent 6 months. Major barriers to implementation included delays in receiving screening results, difficulty meeting screening and decolonization timelines, and staffing turnover. SA screening and decolonization was successfully implemented as a standard of care at our institution with the aid of an implementation science framework. By engaging care partners and healthcare staff throughout the implementation process and regularly addressing barriers, we developed a sustainable SA screening and decolonization program. Adjustments are ongoing to increase and sustain decolonization uptake.

The Canadian Stroke Best Practice Recommendations (CSPR) 7th edition includes this new module on the diagnosis and management of vascular cognitive impairment (VCI) with or without neurodegenerative disease. An expert writing group and people with VCI lived experience (PWLE) reviewed current evidence. Existing recommendations were reviewed and revised, and new recommendations added. Sections include definitions, signs and symptoms, screening, assessment, diagnosis, pharmacological and non‐pharmacological management, secondary prevention, rehabilitation, and end‐of‐life care. PWLE were actively involved in all aspects of the development, ensuring their experiences are integrated. A unique VCI journey map, developed by PWLE, is included, and helped to motivate and anchor the recommendations. We encourage it to be displayed across healthcare settings to raise awareness and support persons with VCI. These VCI CSBPRs emphasize the need for integrated multidisciplinary care across the continuum. Evidence for the diagnosis and management of VCI continues to emerge and gaps in knowledge should drive future research.HighlightsThis Canadian Stroke Best Practice Recommendations module focuses specifically on VCI using a structured framework and validated methodology.A comprehensive set of evidence‐based recommendations is presented that addresses the continuum from symptom onset to diagnosis, management, and end of life.The recommendations consider individuals who experience VCI because of stroke or because of other vascular pathologies such as atrial fibrillation or heart failure.A journey map of an individual's experience with VCI has been developed by individuals with lived experience. It is a valuable guide to inform educational content, approaches to caring for individuals and families with VCI, and systems planning.

Most follicular cell-derived differentiated thyroid carcinomas are regarded as low-risk neoplasms prompting conservative therapeutic management. Here, we provide consensus recommendations reached by a multidisciplinary group of endocrinologists, medical oncologists, pathologists, radiation oncology specialists, a surgeon and a medication reimbursement specialist, addressing more challenging forms of this malignancy, focused on radioactive iodine (RAI)-resistant or -refractory differentiated thyroid carcinoma (RAIRTC). In this document we highlight clinical, radiographic, and molecular features providing the basis for these management plans. We distinguish differentiated thyroid cancers associated with more aggressive behavior from thyroid cancers manifesting as poorly differentiated and/or anaplastic carcinomas. Treatment algorithms based on risk-benefit assessments of different multimodal therapy approaches are also discussed. Given the scarcity of data supporting management of this rare yet aggressive disease entity, these consensus recommendations provide much needed guidance for multidisciplinary teams to optimally manage RAIRTC.

4098 Background: Advances in systemic therapy for HCC have increased treatment options, including TKIs and immunotherapy combinations. Variables that predict patient outcomes may be helpful in personalizing treatment decisions. The aim of this study was to identify predictors of short-term death (STD) and long-term survival (LTS) for HCC patients. Methods: Retrospective review of patients with advanced HCC who received a TKI or immunotherapy combinations was conducted between Aug 2018 to Aug 2022 in the Canadian provinces of British Columbia, Alberta, Nova Scotia, Manitoba, as well as from select institutions in Ontario (n = 2). Prior locoregional therapies were permitted. Variables examined were: Barcelona Clinic Liver Cancer (BCLC) stage, Child-Pugh class, albumin-bilirubin (ALBI) grade, alpha fetoprotein (AFP) level, microvascular invasion (MVI), and distant metastases. Multivariate logistic regression was used to determine independent predictors of STD (patient survival &lt; 6 months vs others) and LTS (patient survival &gt; 18 months vs others). Results: 520 patients with the following baseline characteristics were included: median age 66, 84.6% male, 87.4% ECOG performance status 0-1, 69.7% BCLC stage C, and 88.7% Child-Pugh A. First-line treatments were primarily: lenvatinib 57.3%, sorafenib 8.1%, and atezolizumab/bevacizumab 31.7%. Median progression-free survival was 7.4 months (95% CI: 6.2 to 8.4), and overall survival was 17.1 months (95% CI:, 15.1 to 18.8). Independent predictors of STD were (odds ratio): ALBI grade (2.26), MVI (2.13), and distant metastases (2.14). These three factors were also predictive for LTS: ALBI grade (0.45), MVI (0.49), and distant metastases (0.36). Child-Pugh class, AFP, and BCLC stage were not predictive of STD nor LTS (Table). Conclusions: This study supports higher ALBI grade, MVI and distant metastases as predictors of STD, while lower ALBI grade, absence of MVI and lack of distant metastases were predictive of LTS in HCC patients treated with contemporary TKIs or immunotherapy combination regimens. These predictors may help guide treatment decisions in patient populations underrepresented in clinical trials, including patients with Child-Pugh B7 score who are often excluded. [Table: see text]