Canadian Cancer Centers Research Articles

Evolution in the diagnosis and treatment of carcinoma of unknown primary: a multicenter Canadian analysis

Abstract Background Guidelines for the management of patients with cancer of unknown primary (CUP), who have metastatic disease without an identified primary tumor site, have evolved. We sought to describe the diagnostic work-up and outcomes of patients with CUP in Canada over the last decade. We also sought to identify factors associated with improved prognosis in CUP, including primary tumor site identification, identification of “favorable subtypes,” and concordance with published guidelines. Methods With ethics board approval, patients with histologically confirmed CUP between 2012 and 2021 in 3 Canadian cancer centers were reviewed and clinicopathological variables retrospectively collected. The primary endpoint was to describe significant trends in CUP diagnosis and management over the decade using linear regression models. Univariable (UVA) and multivariable (MVA) logistic regression analyses identified variables correlated with primary site identification and overall survival (OS). Kaplan–Meier curves with the log-rank test were used to compare OS outcomes. Results In total, 907 patients were included, with a median follow-up of 5.1 months. There was an increase in both 5-year survival and identification of primary tumors over the decade. Diagnostic tests including next-generation sequencing were independently associated with primary site identification on UVA. However, primary site identification was not found to be predictive of survival; instead, patients with “favorable subtypes” of CUP had significantly longer OS. Conclusions Survival in patients with CUP in Canada has been increasing over the last decade. Identifying the primary site does not influence survival, and efforts should be focused on discovering novel “favorable subtypes” which have superior outcomes.

59 Measurement of Occupational Radon Levels Over Two Seasons in the Radiation Therapy Department at a Canadian Cancer Centre

59 Measurement of Occupational Radon Levels Over Two Seasons in the Radiation Therapy Department at a Canadian Cancer Centre

Real-World Outcomes of Atezolizumab with Bevacizumab Treatment in Hepatocellular Carcinoma Patients: Effectiveness, Esophagogastroduodenoscopy Utilization and Bleeding Complications.

The IMbrave150 trial established atezolizumab with bevacizumab (A+B) as standard care for hepatocellular carcinoma (HCC), recommending an esophagogastroduodenoscopy (EGD) within 6 months of treatment initiation to prevent bleeding from esophagogastric varices. The necessity of mandatory EGD for all patients remains unclear. We retrospectively analyzed 112 HCC patients treated with A+B at five Canadian cancer centers from 1 July 2020 to 31 August 2022. A+B was the first-line therapy for 90% of patients, with median overall survival at 20.3 months and progression-free survival at 9.6 months. There was no survival difference between patients with bleeding and those without. Before A+B, 71% (n = 79) of patients underwent an EGD within 6 months, revealing varices in 41% (n = 32) and requiring intervention in 19% (n = 15). The overall bleeding rate was 15% (n = 17), with GI-specific bleeding occurring in 5% (n = 17). In the EGD group, GI-specific bleeding was 6% (n = 5) while in the non-EGD group, it was 3% (n = 1). Non-GI bleeding was observed in 10% (n = 11) of patients. Outcomes for HCC patients treated with A+B in Canada were comparable to IMbrave150. There was no increase in GI bleeding in patients without pre-treatment EGD, possibly supporting a selective EGD approach.

Neoadjuvant immuno-chemotherapy in resectable non-small cell lung cancer: A retrospective cohort study.

e20077 Background: Neoadjuvant (NA) nivolumab-chemotherapy (nivo-chemo) has shown an improved survival and pathological complete response (pCR) rate, vs chemo alone, in early-stage, resectable non-small cell lung cancer (NSCLC). Nevertheless, there is a paucity of real-world data. Methods: We performed a real-world, retrospective analysis of outcomes and toxicities in patients with resectable NSCLC (stage IB-IIIA; EGFR/ALK alterations excluded) treated with three cycles of NA nivo-chemo followed by surgery at a single, tertiary-level Canadian cancer centre from September 2022 to September 2023. Results: Fifteen patients were treated with NA nivo-chemo. The median age was 70 years (range, 58 to 78) and 66% were males. 20% (n-3) and 40% (n-6) had N1 and N2 nodes, respectively. All patients completed three cycles of NA nivo-chemo. Objective response rate was 73% (n-11); including 1 complete response. Progression was noted in two patients (the CT predated initiation of treatment by more than 8 weeks in these patients). The median time to surgery was 10.6 weeks (range, 6-17.5). 80% patients (n-12) had a surgery (1 pneumonectomy, 11 lobectomies); and of these, 83% (n-10) are on surveillance while two patients had an event (death or progression). All (n-11) had R0 resection except one. 33% patients (n-5) had a pCR, including two with stage IIIA disease (PDL1 TPS < 1% in three patients, PDL1 TPS ≥ 50% in two patients). 60% patients were started at a reduced chemo dose in cycle 1. 25% patients required further dose reduction. Grade 3 or 4 toxicities were seen in 25% patients (n-4) (neutropenia (n-2), febrile neutropenia (n-1) and pneumonitis (n-1)). Surgical complications were seen in 33% patients (n-5), including death in one patient due to postoperative intrathoracic bleed. Conclusions: NA nivo-chemo in resectable NSCLC is safe and associated with improved pCR rate. A few patients may progress on NA treatment or have a grade 3-5 toxicity precluding curative surgery. Hence, individualized informed decisions should be made. There is an unmet need of biomarkers/models that can predict pCR/toxicity for better patient selection. [Table: see text]

The Association of Ethnicity and Oncologic Outcomes for Oral Cavity Squamous Cell Carcinoma (OSCC).

(1) Background: To compare oncologic outcomes of South Asian (SA) patients treated for oral squamous cell carcinoma (OSCC) to the general population. (2) Methods: Adult patients who underwent surgical resection of OSCC +/- adjuvant treatment between 2009 and 2022 (N = 697) at a regional cancer centre in Canada were included. SA patients, identified using a validated method, were compared to non-SA patients. Kaplan-Meier methods were used to compare the primary outcomes, disease-specific survival (DSS) and recurrence-free survival (RFS) across baseline univariate characteristics, including betel nut consumption. Median follow-up time was 36.4 months. Cox proportional hazard models were used to identify independent predictors of survival with significance set at p < 0.05. (3) Results: SA patients (9% of cohort, N = 64) were significantly younger and had lower rates of smoking and alcohol consumption compared to non-SA patients (p < 0.05). SA patients had a two-fold higher risk of recurrence and significantly worse disease-specific survival, even after adjusting for stage and high-risk features [RFS: HR 2.01 (1.28-3.14), DSS: HR 1.79 (1.12-2.88)]. The consumption of betel nut was not associated with outcomes. (4) Conclusions: SA patients had significantly worse oncologic outcomes, even after controlling for known predictors of poor prognosis. These findings are novel and can inform personalized treatment decisions and influence public health policies when managing patients with different ethnic backgrounds.

Enhanced Recovery After Surgery in Immediate DIEP Flap Breast Reconstruction: Reducing Length of Stay and Opioid Use

Background: To improve patient outcomes amid reduced healthcare resources during the COVID-19 pandemic, a single Canadian cancer center implemented an Enhanced Recovery After Surgery (ERAS) protocol for autologous DIEP flap breast reconstruction. Methods: This retrospective cohort study included 100 consecutive patients undergoing microsurgical breast reconstruction with DIEP flaps using the ERAS protocol and 100 patients using a standard protocol. Primary outcomes were the hospital length of stay and opioid use. Secondary outcomes included postoperative complications, laxative and antiemetic consumption. Results: In this study, 80% of the patients had immediate reconstruction, while the remaining patients received either delayed immediate or delayed reconstruction. Patients in the ERAS group had shorter hospital stays (2.8 vs 4.5 days; P &lt; 0.001) and lower total opioid use (50.2 vs 136.3 mg; P &lt; 0.001). This reduction was also observed when breaking down opiates per day of hospitalization (30.2 vs 18.2 mg; P &lt; 0.001), and in the first 24 postoperatively hours (35.7 vs 67.6 mg; P &lt; 0.001). The control group had a higher incidence of postoperative complications, including seroma, partial and total flap necrosis, compared to the ERAS group. However, readmission rates were similar between the two groups. Conclusion: Implementing the ERAS protocol for DIEP flap breast reconstruction can significantly reduce hospital length of stay and postoperative opioid requirements without increasing the risk of adverse events. This pattern holds true for immediate reconstructions with DIEP flaps.

Real-world treatment outcomes in patients with advanced renal cell carcinoma who receive axitinib plus pembrolizumab in the first-line setting in Canadian cancer centers.

Real-world treatment outcomes in patients with advanced renal cell carcinoma who receive axitinib plus pembrolizumab in the first-line setting in Canadian cancer centers.

A pre-implementation examination of barriers and facilitators of an electronic prospective surveillance model for cancer rehabilitation: a qualitative study

BackgroundAn electronic Prospective Surveillance Model (ePSM) uses patient-reported outcomes to monitor symptoms along the cancer pathway for timely identification and treatment. Randomized controlled trials show that ePSMs can effectively manage treatment-related adverse effects. However, an understanding of optimal approaches for implementing these systems into routine cancer care is limited. This study aimed to identify barriers and facilitators prior to the implementation of an ePSM to inform the selection of implementation strategies.MethodsA qualitative study using virtual focus groups and individual interviews was conducted with cancer survivors, oncology healthcare providers, and clinic leadership across four cancer centres in Canada. The Consolidated Framework for Implementation Research (CFIR) guided the interviews and analysis of barriers and facilitators based on five domains (intervention characteristics, individual characteristics, inner setting, outer setting, and process).ResultsWe conducted 13 focus groups and nine individual interviews with 13 patient participants and 56 clinic staff. Of the 39 CFIR constructs, 18 were identified as relevant determinants to the implementation. The adaptability, relative advantage, and complexity of an ePSM emerged as key intervention-level factors that could influence implementation. Knowledge of the system was important at the individual level. Within the inner setting, major determinants were the potential fit of an ePSM with clinical workflows (compatibility) and the resources that could be dedicated to the implementation effort (readiness for implementation). In the outer setting, meeting the needs of patients and the availability of rehabilitation supports were key determinants. Engaging various stakeholders was critical at the process level.ConclusionsImproving the implementation of ePSMs in routine cancer care has the potential to facilitate early identification and management of treatment-related adverse effects, thereby improving quality of life. This study provides insight into important factors that may influence the implementation of an ePSM, which can be used to select appropriate implementation strategies to address these factors.

Tumor volumes in T3 supraglottic cancers treated with radiotherapy in the modern era: A study of the Canadian Head & Neck Collaborative Research Initiative.

To evaluate the association of primary tumor volume (TV) with overall survival (OS) and disease-free survival (DFS) in T3 N0-3M0 supraglottic cancers treated with intensity-modulated radiotherapy (IMRT). This was a retrospective cohort study involving 239 patients diagnosed with T3 N0-3M0 supraglottic cancers between 2002 and 2018 from seven regional cancer centers in Canada. Clinical data were obtained from the patient records. Supraglottic TV was measured by neuroradiologists on diagnostic imaging. Kaplan-Meier method was used for survival probabilities, and a restricted cubic spline Cox proportional hazards regression analysis was used to analyze TV associations with OS and DFS. Mean (SD) of participants was 65.2 (9.4) years; 176 (73.6%) participants were male. 90 (38%) were N0, and 151 (64%) received concurrent systemic therapy. Mean TV (SD) was 11.37 (12.11) cm3 . With mean follow up (SD) of 3.28 (2.60) years, 2-year OS was 72.7% (95% CI 66.9%-78.9%) and DFS was 53.6% (47.4%-60.6%). Increasing TV was associated (per cm3 increase) with worse OS (HR, 1.01, 95% CI 1.00-1.02, p < 0.01) and DFS (HR, 1.01, 95% CI 1.00-1.02, p = 0.02). Increasing primary tumor volume is associated with worse OS and DFS in T3 supraglottic cancers treated with IMRT, with no clear threshold. The findings suggest that patients with larger tumors and poor baseline laryngeal function may benefit from upfront laryngectomy with adjuvant radiotherapy.

Clinical impact of unsuccessful subcutaneous administration of octreotide LAR instead of intramuscular administration in patients with metastatic gastroenteropancreatic neuroendocrine tumors.

Octreotide LAR is a long-acting somatostatin analogue (SSA) used in the management of metastatic gastroenteropancreatic neuroendocrine tumors (GEP NETs). It requires intramuscular (IM) injection. Missed IM injections cause subcutaneous nodules (SCNs) on radiologic images. We reviewed the rates of SCNs in a real-world cohort of GEP NETs receiving octreotide LAR and explored treatment outcomes. Patients commencing octreotide LAR between August 5, 2010 and March 8, 2018 at a single cancer center in Canada were identified from pharmacy records. Patients were included if they had a computed tomography (CT) scan performed at the time of progression and a preceding CT with pelvis included to enable assessment for the presence of nodules. Fisher's exact test was used to examine predictors of SCNs, and Kaplan-Meier curves summarized differences in progression free (PFS) and overall survival (OS) that were compared with log-rank tests. Of 243 patients receiving octreotide LAR, 45 had all required CT images available for central review. SCNs were found in 20/45 (44%) of patients on the last scan showing stable disease before progression and were numerically but not statistically more likely in females (OR: 2.36, 95% CI: 0.66-8.29, p = .23). There was an increased risk of SCNs in patients with a skin-to-muscle distance >38 mm (the length of an octreotide LAR needle) on CT (OR: 5.09, 95% CI: 1.39-16.6, p = .018) and a trend toward increased risk in obese patients (OR: 5.71, 95% CI: 1.26-23.4, p = .061). PFS (HR: 1.01, 95% CI: 0.56-1.78, p = .98) and OS (HR: 0.86, 95% CI: 0.41-1.8, p = .70) was similar between those with/without SCNs. In conclusion, almost half of patients receiving octreotide LAR had SCNs; however, missed administration of SSA did not appear to result in worse survival in this small study. Factors such as sex, younger age skin-to-muscle distance, and obesity may affect SCN development and should be considered when choosing an SSA.

Minding the gaps: assessing and addressing clinical research core competencies across a network of Canadian cancer centres.

The Canadian Cancer Clinical Trials Network (3CTN, the Network), established in 2014 to address the decline in academic cancer clinical trials' (ACCT) activity, has successfully achieved incremental year-over-year accrual targets as well as implemented recognized performance measures and supports for improving efficiency and quality of trial activities at member sites across Canada. As part of efforts to address ongoing challenges of staff recruitment, retention, and turnover in academic institutions that have been more recently exacerbated by the pandemic, the Network's Performance Strategy Sub-Committee (PSC) oversaw surveys of site clinical research professionals intended to capture workforce development status and identify knowledge gaps using the Joint Task Force Core Competency Framework (JTF CCF) as the standard basis for assessment. Accountable to the 3CTN Management Committee, the PSC consists of clinical research operations experts across Canada responsible for overseeing implementation and monitoring progress of this initiative. Staff at 3CTN's adult sites evaluated and reported trial personnel core competencies and gaps according to each domain/leveled competency statement of the framework. The most frequently noted competency gaps were in the domains of: Investigational Product Development and Regulation (28%); Scientific Concepts and Research Design (16%); and Study and Site Management (14%). Reported data was compiled and represented in the 3CTN Core Competency Report, developed as a web-based, interactive tool enabling members and stakeholders to filter data to enumerate and quantify workforce competency gaps at their site, within their node of affiliated sites, or across the national Network. Concurrently, an environmental scan and review of education resources was conducted and reviewed by the PSC. Embedded links to curated learning and development resources were incorporated into the report and associated with each domain/leveled competency statement to provide ready access to high-quality learning and development resources where needed. In the remaining years of its current strategic plan, 3CTN will continue to monitor, develop collaborative initiatives to target prioritized clinical research competency gaps and create opportunities for ongoing assessment and reporting by sites to capture changes in workforce core competencies over time.

Practice Patterns of Medical Oncologists: A Survey of Advance Care Planning in the Outpatient Setting

Introduction. Advance care planning (ACP) is an important part of cancer care. We determined the ACP practice patterns of medical oncologists at our academic cancer centre in Canada. Methods. Medical oncologists were invited to participate in a questionnaire in August 2019. Questions were validated by a local survey expert. Twelve multiple-choice questions were included. Results. Seventeen of the 23 eligible oncologists responded. 64% were male, and 76% were in practice for &lt;16 years. Common tumour sites treated by respondents included breast (53%), lung (24%), gastrointestinal (24%), and genitourinary (24%) cancers. Oncologists responded that components of ACP included designating a substitute decision-maker (100%), determining goals of care (100%), making decisions about cardiopulmonary resuscitation (94%), and disposition of property/finances (88%). They discuss ACP with curable vs. incurable patients 6% vs. 93% of the time. While 88% of oncologists reported it would be desirable to initiate ACP discussions in the first 3 visits, in the incurable setting, only 29% reported doing so. Patient characteristics that prompt oncologists to discuss ACP in the first 3 visits in the curative vs. incurable settings include elderly age (23% vs. 59%), poor performance status (47% vs. 88%), and short prognosis (47% vs. 88%). Oncologists thought the most appropriate time to discuss ACP in the curative setting was at the time the patient initiates it (35%), and during visits 2-3 in the incurable setting (41%). The most common barriers to discussing ACP include insufficient time (71%) and too much information for the patient (71%). Conclusions. While medical oncologists believe that discussing ACP with cancer patients in the first few outpatient visits is important, this seldom occurs due to the presence of several barriers.

133 Predictors of Staff Satisfaction, Stress, and Burnout at a Canadian Cancer Centre

133 Predictors of Staff Satisfaction, Stress, and Burnout at a Canadian Cancer Centre

Programmed Cell Death Protein 1 Inhibitors and MET Targeted Therapies in NSCLC With MET Exon 14 Skipping Mutations: Efficacy and Toxicity as Sequential Therapies

IntroductionNSCLC with MET exon 14 skipping mutation (METex14) is associated with poor outcomes. Integration of novel targeted therapies is challenging because of barriers in testing and drug access. We, therefore, sought to characterize the treatment patterns, outcomes, and emerging issues of treatment sequencing in patients with METex14-mutant NSCLC. MethodsWe reviewed all NSCLC cases with METex14 alterations between 2014 and 2020 across four Canadian cancer centers. Demographics, disease characteristics, systemic therapy, overall response rates (ORRs), survival, and toxicity were summarized. ResultsAmong 64 patients with METex14-mutant NSCLC, the median overall survival was 23.1 months: 127.0 months in stage 1, 27.3 months in resected stage 2 and 3, and 16.6 months in unresectable stage 3 or 4 disease, respectively. In patients with advanced disease, 22% were too unwell for systemic treatment. MET tyrosine kinase inhibitors (TKIs) were administered to 28 patients with an ORR of 33%, median progression-free survival of 2.7 months, and 3.8 months for selective TKIs. Programmed cell death protein-1 (PD-1) inhibitors were given to 25 patients—the ORR was 44% and progression-free survival was 10.6 months. No responses were seen with subsequent MET TKIs after initial TKI treatment. Grade 3 or higher toxicities occurred in 64% of patients who received MET TKI after PD-1 inhibitors versus 8% in those who did not receive PD-1 inhibitors. ConclusionsMany patients with advanced METex14 NSCLC were too unwell to receive treatment. PD-1 inhibitors seem effective as an initial treatment, although greater toxicity was seen with subsequent MET TKIs. Thus, timely testing for METex14 skipping and initial therapy are imperative to improving patient survival.

Telephone completion of patient self-reporting health history documents by registered nurses: a survey to evaluate its effectiveness and strategies for improvement.

Prior to the COVID-19 pandemic, cancer patients would complete their self-reporting health history documentation at their initial consultation visit. With the increase in virtual care, a program was established; whereby, a registered nurse (RN) would complete the self-reporting history with the patient by telephone prior to the initial consultation. A survey of RNs and oncologists evaluating the effectiveness of this program is presented. Outpatient RNs and medical and radiation oncologists were surveyed at a single Canadian cancer center. The surveys collected demographic information and perceptions around the successes and challenges of this program. Responses were received from 31/42 (74%) RNs and 29/48 (60%) oncologists. RNs reported calling an average of 4 patients/week, and the median time for each call was 20min. For responding RNs, 21/31 (68%) felt patients were satisfied with the process, and 18/31 (58%) were satisfied with the quality and efficacy of care they were delivering. 25/31 (81%) RNs felt the telephone calls improved care when the patient came to the clinic. All (100%) oncologists were aware of the program, and 86% (25/29) felt it saved time at the consult visit. Areas for improvement included patients completing the forms themselves and including information on current symptoms and drug insurance status. COVID-19 has resulted in many changes in oncology practice. Completion of patient self-reported health history documentation by an RN over the telephone prior to consultation visit received positive feedback from both RNs and oncologists. However, this process has considerable RN resource implications.

Real-World Analysis of Durvalumab after Chemoradiation in Stage III Non-Small-Cell Lung Cancer.

The 2017 PACIFIC trial heralded the incorporation of routine adjuvant durvalumab following curative-intent chemoradiation for stage III non-small-cell lung cancer (NSCLC). However, carefully selected clinical trial populations can differ significantly from real-world populations, which can have implications on treatment toxicities and outcomes, making it difficult to accurately counsel patients. Consequently, we performed a real-world, retrospective analysis of outcomes and toxicities in 118 patients with stage III NSCLC treated with durvalumab after platinum-based chemoradiotherapy. The data were collected from patients who underwent treatment at a single, tertiary-level Canadian cancer centre from May 2018 to October 2020. The variables collected included patient demographics, treatment specifics, progression-free survival, overall survival, and immune-related adverse events (IRAE) from durvalumab. Descriptive statistics were used for toxicity analysis, and progression-free survival and overall survival estimates were calculated using the Kaplan-Meier method. The statistical analyses indicated a 64.4% (n = 76) toxicity rate, with a 21% (n = 25) toxicity rate of grade 3+ IRAEs. The most common documented IRAEs were pneumonitis (n = 44; 40%), followed by rash (n = 20; 18%) and thyroid dysfunction (n = 17; 15%). FEV1 and DLCO were not found to be associated predictors of pneumonitis toxicity. The median PFS and OS were estimated to be >1.7 years and >2.7 years, respectively.

Small Bowel Neuroendocrine Tumors-10-Year Experience of the Ottawa Hospital (TOH).

(1) Aim: The prevalence and incidence of small bowel NETs have increased significantly over the past two decades. This study aims to report the 10-year experience of SB-NET management at a regional cancer center in Canada. (2) Materials and methods: We conducted a retrospective study of the clinical and pathological data of patients diagnosed with biopsy-proven SB-NET at The Ottawa Hospital (TOH), Ottawa, Canada between 2011 and 2021. We report the clinicopathological characteristics of these patients, as well as their outcomes data, including survival rates. (3) Results: Between 2011 and 2021, a total of 177 SB-NET cases were identified with 51% (n = 91) of cases being males. The most common sites of the tumors were the ileum 53% (n = 94), followed by the duodenum 9% (n = 16) and jejunum 7% (n = 12). Approximately 24% (n = 42) of the patients had symptoms for over six months prior to diagnosis and 18% (n = 32) had functioning SB-NET during the course of the disease. The majority of patients had locally advanced or metastatic disease at the time of presentation with stage III, and stage IV representing 42% (n = 75), and 41% (n = 73) respectively. The majority of patients 84% (n = 148) had well-differentiated histology. One hundred twenty patients underwent surgical resection of the primary tumor including 28 patients (16%) with limited metastatic disease. A total of 21 patients (18%) had recurrence after curative surgery. A total of 62 patients (35%) received first-line somatostatin analog (SSA) therapy for unresectable disease and seven patients had PRRT after progression on SSA. Five years OS was 100%, 91%, 97%, and 73% for stages I, II, III, and IV respectively. In univariate analysis, carcinoid symptoms, T stage, and differentiation were significant predictors for worse overall survival, but not RFS. (4) Conclusions: Compared to published historical controls, our study suggests improvement in the 5-year survival rate of SB-NETs over the last 10 years.

Resuscitation outcomes in patients with cancer: experience in a large urban cancer centre.

Hospitalized patients with cancer who experience cardiopulmonary arrest have historically low survival rates. This retrospective cohort study describes outcomes of patients at a large Canadian cancer centre who had a "code medical emergency" activated, and the use of pragmatic criteria to identify patients with poor survival following resuscitation. We included hospitalized patients with cancer who had a "code blue" activated between January 2007 and December 2018. Our primary outcome was intensive care unit (ICU) mortality. We developed pragmatic criteria to identify patients with "poor prognosis" for survival from cardiopulmonary resuscitation (CPR) based on disease status and candidacy for further cancer treatment. We used descriptive statistics to analyze the outcomes of poor prognosis patients. Two hundred and twenty-five patients had a code blue activated. The median age was 61 yr, 52% were male, and 48% had a solid tumour. Overall, 173/225 (77%) patients survived the code blue; 164 were admitted to the ICU, where 49% (81/164) died; 31% survived to hospital discharge; and 16% (n=27) were alive at one year. One hundred and twenty out of 225 (53%) required chest compressions; spontaneous circulation returned in 61% (73/120), and 12% (14/120) survived to hospital discharge. Patients meeting "poor prognosis" criteria (114, 51%) were more likely to die in the ICU (64% vs 35%; P<0.001) or in hospital (86% vs 59%; P<0.001), and more often had goals-of-care discussions prior to the code blue (46% vs 7%; P<0.001). At one year, only 2% of poor prognosis patients were alive, compared with 24% of patients who did not meet any poor prognosis criteria. Hospitalized patients with cancer requiring CPR have poor hospital and long-term outcomes. The proposed set of pragmatic criteria may be useful to identify patients unlikely to benefit from CPR and life support, to trigger early goals of care discussions, and to avoid potentially goal-discordant interventions.

Disparities in clinical trial enrolment at a Canadian comprehensive cancer centre: A 15-year retrospective study.

6550 Background: Disparities in clinical trials limit the generalizability of study findings and perpetuate disparities in treatment access and outcomes, but there is a paucity of data in the Canadian context. The objective of this study was to examine disparities in cancer clinical trial enrollment at a large, comprehensive Canadian cancer center. Methods: We conducted a retrospective cohort study of clinical trial enrollment among all newly diagnosed cancer patients (N=154,880) at the Princess Margaret Cancer Centre in Toronto, Canada (2006-2021). Multivariable Bayesian hierarchical logistic regression with random effect for most responsible physician was used to examine the correlates of clinical trial enrollment, comparing the population of enrolled and non-enrolled patients. Odds ratios were adjusted for patient variables (sex, age at diagnosis, language, geography, primary care provider), and census tract-level marginalization (residential instability, material deprivation, dependency, ethnic concentration), disease variables (cancer site and disease stage at diagnosis), and provider variables (most responsible physician (MRP), and MRP’s sex, language, medical training, and department). Results: Overall, 11.2% of patients enrolled (n=17,400) in a clinical trial, with 5-, 10-, and 15-year cumulative incidences of 12%, 15%, and 18%, respectively. Small, but significant differences were observed between enrollees and the overall patient population. Lower odds of enrollment were observed in patients who were female (adjusted odds ratio [AOR], 0.82; 95% confidence interval [CI], 0.78-0.86; p&lt;.001), ≥65 years (AOR vs &lt;40, 0.61; 95% CI, 0.56-0.65; p&lt;.001), non-English language speakers (AOR vs English, 0.72; 95% CI, 0.67-0.77; p&lt;.001), lived ≥250 km away from the cancer center (AOR vs &lt;15km, 0.71; 95% CI, 0.62-0.80; p&lt;.001), or lived in areas with greater material deprivation (AOR, 0.94; 95% CI, 0.93-0.96; p&lt;.001) or higher ethnic concentration (AOR, 0.96; 95% CI, 0.94-0.98; p&lt;.001). Greater odds of enrollment were found in patients with metastatic disease (AOR, 1.19; 95% CI, 1.13-1.25; p&lt;.001) and in those with a primary care provider (AOR, 1.69; 95% CI, 1.55-1.85; p&lt;.001). Conclusions: Disparities were observed in clinical trial enrollment, despite a publicly funded health care system. While broader prospective data collection efforts are critical to better understand the influence of patient, provider and system factors on clinical trial enrollment, these findings suggest the need for targeted strategies to increase diversity in clinical trial access.

Understanding treatment toxicity patterns through remote symptom monitoring and examining the effect of frailty in older men with metastatic prostate cancer.

12054 Background: Advancements in metastatic prostate cancer (mPC) treatments have increased survival, but using multiple lines of therapy has increased the prevalence and severity of toxicities. Older men and those living with frailty experience higher symptom burden associated with treatment. Although toxicities have been described in previous trials, much of the focus has been on pain and fatigue among fit and younger men, and only a few trials have examined the effects of frailty on toxicity. Thus, the aims of this study were to (1) understand the prevalence, duration, and changes in symptom severity among older men receiving mPC treatments; and (2) examine differences among frail and non-frail men. Methods: Men aged 65+ with mPC starting chemotherapy (chemo), androgen receptor-axis-targeted (ARAT) therapies, or radium-223 (Rad223) from two academic Canadian cancer centres were enrolled in a prospective cohort study. Participants self-reported symptoms daily using the Edmonton Symptom Assessment Scale (ESAS) for the first treatment cycle via internet or telephone. Frailty status was determined using the Vulnerable Elders Survey (VES-13). Study outcomes were the development of moderate-to-severe symptoms (ESAS≥4), their duration, and the proportion of participants who had improvements in symptom severity (ESAS&lt;4) after reporting moderate-to-severe symptoms at baseline. Outcomes were determined using descriptive statistics. Associations between symptom prevalence, duration, and frailty were assessed using t-tests and chi-square tests. Results: 90 men (mean age=77 +/- 6.1 years, 58% frail (VES-13≥3)) starting chemo (n=34), an ARAT (n=43), or Rad223 (n=13) were included. The most common moderate-to-severe symptoms across cohorts were fatigue (46.8%), insomnia (42.9%), poor wellbeing (41.2%), decreased appetite (37.1%), and pain (35.9%). These symptoms were numerically higher in frail men, but differences between frail and non-frail were only statistically significant for poor wellbeing (62.5% in frail vs. 31.4% in non-frail, p=0.039). On average, poor wellbeing lasted 6.5 days (SD=7.6) days, decreased appetite lasted 5.5 days (SD=4.9), fatigue lasted 5.1 days (SD=7.3), pain lasted 4.7 days (SD=5.6), and insomnia lasted 4.6 days (SD=6.2) across cohorts. Fatigue and pain lasted numerically longer in frail men whereas insomnia, poor wellbeing, and decreased appetite lasted numerically longer in non-frail men, but these differences were not statistically significant. Among participants who reported moderate-to-severe symptoms at baseline, 15.4%, 10.7%, 7.7%, 5.3% and 3.6% had improvements in pain, appetite, wellbeing, insomnia, and fatigue, respectively. Conclusions: Understanding temporal patterns of symptoms and the impact of frailty in older men receiving mPC treatments may help inform supportive care approaches. Clinical trial information: NCT04193657 .