Disparities in clinical trial enrollment at a Canadian comprehensive cancer center: A 15-year retrospective study

INTRODUCTION

Disparities in clinical trials (CTs) enrollment perpetuate inequities in treatment access and outcomes, but there is a paucity of Canadian data. The objective of this study was to examine disparities in cancer CT enrollment at a large Canadian comprehensive cancer center.

METHODS

Retrospective study of CT enrollment among new patient consultations from 2006 to 2019, with follow-up to 2021 (N = 154,880), with the primary outcome of enrollment as a binary variable. Factors associated with CT enrollment were evaluated using multivariable Bayesian hierarchical logistic regression with random effects for most responsible physician (MRP) and geography, adjusted for patient characteristics (sex, age, language, geography, and primary care provider [PCP]), area-level marginalization (residential instability, material deprivation, dependency, and ethnic concentration), disease (cancer site and stage), and MRP (department, sex, language, and training). A sensitivity analysis of the cumulative incidence of enrollment was conducted to account for differences in disease type and follow-up length.

RESULTS

CT enrollment was 11.2% overall, with a 15-year cumulative incidence of 18%. 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), ≥65 years (AOR vs. <40, 0.61; 95% CI, 0.56-0.66), non-English speakers (0.72; 95% CI, 0.67-0.77), living ≥250 km away (AOR vs. <15 km, 0.71; 95% CI, 0.62-0.80), and without a PCP. Disease characteristics accounted for the largest proportion of observed variation (20.8%), with significantly greater odds of enrollment in patients with genitourinary cancers and late-stage disease.

CONCLUSION

Significant sociodemographic disparities were observed, suggesting the need for targeted strategies to increase diversity in access to cancer CTs in Canada.

Evaluating the impact of a national geriatric mental health ECHO educational program on healthcare providers' practice

Project Extension for Community Healthcare Outcomes (ECHO) enables healthcare providers to share knowledge and best practices via telementoring. The ECHO model builds provider capacity and improves care for patients with a variety of health conditions. This study describes a Canada-wide National ECHO pilot project in the area of geriatric mental health and reports on the program's impact on providers' care practices. A mixed-methods approach was used to analyze surveys completed by participating healthcare providers. Program evaluation measured satisfaction, achievement of learning objectives, awareness of issues related to geriatric mental health, and comfort and self-efficacy working with older adults. The program led to a statistically significant increase in participants' awareness of issues related to support for older adults with mental illness and comfort and self-efficacy in managing these patients in their own practice. The National ECHO pilot project was successful in building healthcare providers' capacity to care for older adults with mental health issues and positively impacting their practice. These findings support using the ECHO model to provide ongoing geriatric mental health education for clinicians from across Canada and beyond.

A Prospective Study of Machine Learning-Assisted Radiation Therapy Planning for Patients Receiving 54 Gy to the Brain

PURPOSE

The capacity for machine learning (ML) to facilitate radiation therapy (RT) planning for primary brain tumors has not been described. We evaluated ML-assisted RT planning with regard to clinical acceptability, dosimetric outcomes, and planning efficiency for adults and children with primary brain tumors.

METHODS AND MATERIALS

In this prospective study, children and adults receiving 54 Gy fractionated RT for a primary brain tumor were enrolled. For each patient, one ML-assisted RT plan was created and compared with 1 or 2 plans created using standard ("manual") planning procedures. Plans were evaluated by the treating oncologist, who was blinded to the method of plan creation. The primary endpoint was the proportion of ML plans that were clinically acceptable for treatment. Secondary endpoints included the frequency with which ML plans were selected as preferable for treatment, and dosimetric differences between ML and manual plans.

RESULTS

A total of 116 manual plans and 61 ML plans were evaluated across 61 patients. Ninety-four percent of ML plans and 93% of manual plans were judged to be clinically acceptable (P = 1.0). Overall, the quality of ML plans was similar to manual plans. ML plans comprised 34.5% of all plans evaluated and were selected for treatment in 36.1% of cases (P = .82). Similar tumor target coverage was achieved between both planning methods. Normal brain (brain minus planning target volume) received an average of 1 Gy less mean dose with ML plans (compared with manual plans, P < .001). ML plans required an average of 45.8 minutes less time to create, compared with manual plans (P < .001).

CONCLUSIONS

ML-assisted automated planning creates high-quality plans for patients with brain tumors, including children. Plans created with ML assistance delivered slightly less dose to normal brain tissues and can be designed in less time.

Connectedness to the young adult cancer community and post-traumatic growth: A young adults with cancer in their prime study

OBJECTIVE

For young adults (YAs) with cancer, connecting with peer cancer survivors can provide a unique sense of community and may enhance post-traumatic growth (PTG). This study examined the relationship between connectedness to the YA cancer community and PTG among YAs, independent of overall social support.

METHODS

Data were obtained from the young adults with cancer in their prime study, a cross-Canada survey of YA cancer survivors. Participants were stratified by level of social support into two groups (low/high). Multivariable logistic regression was used to examine the association between PTG and connectedness to the YA community adjusting for respondent characteristics, and the interaction between support and connectedness.

RESULTS

Of 444 respondents, mean age was 34.2 (SD = 6.0), time-since-diagnosis was 4.8 years (SD = 5.4), and 87% were female. Over two-thirds of respondents (71%) reported feeling connected to the YA community. Level of connectedness to the YA community did not differ by social support group, and interaction between social support and connectedness to the YA community was not significant. In the adjusted regression, connectedness to the YA community (aOR = 2.29, 95% CI: 1.10-4.91), high social support (aOR = 2.98, 95% CI: 1.36-6.74), greater time-since-diagnosis (aOR = 1.09, 95% CI: 1.04-1.15) and female sex (aOR = 2.21, 95% CI: 1.23-4.04) were associated with greater odds of moderate-to-high PTG.

CONCLUSIONS

Feeling connected to a community of YA cancer peers was associated with moderate-to-high PTG among YAs, independent of overall perceived social support. Future efforts should increase access to YA cancer communities and foster a sense of connectedness among YAs with cancer.

Anal Cancers in Previously Screened Versus Unscreened Patients: Tumor Stage and Treatment Outcomes

BACKGROUND

Targeted screening programs for patients at high risk for anal squamous-cell carcinoma have been proposed; however, the evidence in support of screening remains unclear.

OBJECTIVE

This study aimed to determine whether screening high-risk patients (predominantly those living with HIV) detected squamous-cell carcinoma at an earlier stage compared to the routine practice of not screening.

DESIGN

This is a cohort study.

SETTINGS

This study was conducted at a quaternary care center in Canada.

PATIENTS

Included patients were at least 18 years old with a pathologic diagnosis of invasive anal squamous-cell carcinoma between 2002 and 2022.

INTERVENTIONS

Patients diagnosed through a high-risk screening program were compared to those who did not undergo screening.

MAIN OUTCOME MEASURES

The primary outcome was clinical stage at presentation, categorized as T1N0M0 vs other. Secondary outcomes included treatments received, treatment failure, and overall survival.

RESULTS

A total of 612 patients with anal squamous-cell carcinoma were included, with 26 of those patients diagnosed through a screening program. Patients with screen-detected cancers had greater odds of presenting with T1N0M0 tumors compared to unscreened patients (18 [69.2%] vs 84 [14.3%]; adjusted OR 9.95; 95% CI, 3.95-25.08). A propensity score-matched sensitivity analysis found similar results (OR 11.13; 95% CI, 4.67-26.52). Screened patients had greater odds of treatment with wide local excision alone, as opposed to any combination of chemotherapy, radiation therapy, and surgery (3 [12.5%] vs 18 [3.2%]; OR 4.38; 95% CI, 1.20-16.04). There were no statistically significant differences in treatment failure or overall survival between groups.

LIMITATIONS

The small number of screened patients limits the power of the analysis.

CONCLUSIONS

Screening for anal squamous-cell carcinoma among high-risk populations detects cancers at an earlier stage. Patients with screen-detected cancers also had a greater likelihood of being candidates for wide local excision alone, which may have spared them the morbidity associated with chemoradiotherapy or abdominoperineal resection. See Video Abstract.

CNCERES DE ANO EN PACIENTES PREVIAMENTE DETECTADOS POR CRIBADO VERSUS NO DETECTADOS ESTADIO DEL TUMOR Y RESULTADOS DEL TRATAMIENTO

ANTECEDENTES:Se han propuesto programas de cribado dirigidos a pacientes con alto riesgo de carcinoma anal de células escamosas; sin embargo, la evidencia a favor de la detección sigue sin estar clara.OBJETIVO:Este estudio tuvo como objetivo determinar si el cribado de pacientes de alto riesgo (predominantemente aquellos que viven con el VIH) detectó el carcinoma de células escamosas en una etapa más temprana en comparación con la práctica habitual de no cribado.DISEÑO:Este es un estudio de cohortes.CONFIGURACIÓN:Este estudio se realizó en un centro de atención cuaternaria en Canadá.PACIENTES:Los pacientes incluidos tenían al menos 18 años con un diagnóstico patológico de carcinoma de células escamosas anal invasivo entre 2002 y 2022.INTERVENCIONES:Los pacientes diagnosticados mediante un programa de cribado de alto riesgo se compararon con aquellos que no se sometieron a cribado.PRINCIPALES MEDIDAS DE RESULTADO:El resultado primario fue el estadio clínico en la presentación, categorizado como T1N0M0 versus otro. Los resultados secundarios incluyeron los tratamientos recibidos, el fracaso del tratamiento y la supervivencia general.RESULTADOS:Se incluyeron un total de 612 pacientes con carcinoma anal de células escamosas, con 26 de esos pacientes diagnosticados a través de un programa de cribado. Los pacientes con cánceres detectados mediante cribado tenían mayores probabilidades de presentar tumores T1N0M0 en comparación con los pacientes no cribados (18 [69.2%] frente a 84 [14.3%]; razón de probabilidad ajustada 9.95; intervalo de confianza del 95 % 3.95 -25.08). Un análisis de sensibilidad emparejado por puntaje de propensión encontró resultados similares (odds ratio 11.13; intervalo de confianza del 95% 4.67 -26.52; p < 0.001). Los pacientes examinados tenían mayores probabilidades de recibir tratamiento con escisión local amplia sola, en comparación con cualquier combinación de quimioterapia, radiación y cirugía (3 [12.5%] frente a 18 [3.2%]; razón de probabilidad 4.38; intervalo de confianza del 95 % 1.20 -16.04). No hubo diferencias estadísticamente significativas en el fracaso del tratamiento o la supervivencia global entre los grupos.LIMITACIONES:El pequeño número de pacientes evaluados limita el poder del análisis.CONCLUSIONES:La detección del carcinoma anal de células escamosas entre las poblaciones de alto riesgo detecta los cánceres en una etapa más temprana. Los pacientes con cánceres detectados mediante cribado también tenían una mayor probabilidad de ser candidatos para una escisión local amplia sola, lo que puede haberles evitado la morbilidad asociada con la quimiorradioterapia o la resección abdominoperineal. (Traducción --Dr. Aurian Garcia Gonzalez ).

The influence of the "cancer" label on perceptions and management decisions for low-grade prostate cancer

BACKGROUND

Grade Group 1 (GG1) prostate cancer should be managed with active surveillance (AS). Global uptake of AS remains disappointingly slow and heterogeneous. Removal of cancer labels has been proposed to reduce GG1 overtreatment. We sought to determine the impact of GG1 disease terminology on individual's perceptions and decision making.

METHODS

Discrete choice experiments were conducted on 3 cohorts: healthy men, canonical partners (partners), and patients with GG1 (patients). Participants reported preferences in a series of vignettes with 2 scenarios each, permuting key opinion leader-endorsed descriptors: biopsy (adenocarcinoma, acinar neoplasm, prostatic acinar neoplasm of low malignant potential [PAN-LMP], prostatic acinar neoplasm of uncertain malignant potential), disease (cancer, neoplasm, tumor, growth), management decision (treatment, AS), and recurrence risk (6%, 3%, 1%, <1%). Influence on scenario selection were estimated by conditional logit models and marginal rates of substitution. Two additional validation vignettes with scenarios portraying identical descriptors except the management options were embedded into the discrete choice experiments.

RESULTS

Across cohorts (194 healthy men, 159 partners, and 159 patients), noncancer labels PAN-LMP or prostatic acinar neoplasm of uncertain malignant potential and neoplasm, tumor, or growth were favored over adenocarcinoma and cancer (P < .01), respectively. Switching adenocarcinoma and cancer labels to PAN-LMP and growth, respectively, increased AS choice by up to 17%: healthy men (15%, 95% confidence interval [CI] = 10% to 20%, from 76% to 91%, P < .001), partners (17%, 95% CI = 12% to 24%, from 65% to 82%, P < .001), and patients (7%, 95% CI = 4% to 12%, from 75% to 82%, P = .063). The main limitation is the theoretical nature of questions perhaps leading to less realistic choices.

CONCLUSIONS

"Cancer" labels negatively affect perceptions and decision making regarding GG1. Relabeling (ie, avoiding word "cancer") increases proclivity for AS and would likely improve public health.

A Prospective Study of Machine Learning-Assisted Radiotherapy Planning for Patients Receiving 54 Gy to the Brain

PURPOSE/OBJECTIVE(S)

Radiotherapy (RT) planning is presently a semi-manual, iterative, labor-intensive process which may result in unnecessary variation in plan quality. To improve treatment plan quality and decrease RT planning time, we conducted a prospective, blinded study to compare machine learning-assisted planning with conventional manual planning for patients receiving 54 Gy in 30 fractions for a primary brain tumor.

MATERIALS/METHODS

From January 31, 2022 to January 10, 2023, 40 patients receiving 54 Gy for primary CNS tumors were prospectively enrolled (median age 50 years, range 4-78 years). Patients underwent standard CT/MR simulation and target/OAR delineation by the treating radiation oncologist. Each patient had one ML plan and 1-2 manual RT plans created by different planners. The reviewing oncologist was blinded to planning method by removing optimization and IMRT/VMAT beam arrangement details from all plans, which were then rated based on clinical acceptability, target coverage, OAR sparing, conformity, and dose-fall off. One preferred plan was chosen and used for clinical treatment.

RESULTS

A total of 115 plans for 40 patients were evaluated: 40 ML plans (35% of all plans), and 75 manual plans (65% of all plans; 5 and 35 patients had 1 and 2 manual plans created, respectively). ML plans required a mean planning time of 65 min as compared to 107 min for manual plans, with a mean time savings of 41 min per patient (paired t-test p = 0.002). 97% of ML plans (95% confidence interval [CI] 85-100) and 96% of manual plans (95% CI 87-99) were designated clinically acceptable by the treating radiation oncologist. While ML-assisted plans represented 35% of plans evaluated, they were chosen as preferred for clinical treatment in 43% of cases (17/40, 95% CI 29-58, p = 0.32). Median doses to the brain (10.8 Gy vs. 11.3 Gy, Wilcoxon rank-sum p = 0.012) and brain minus PTV (9.2 Gy vs 10.0 Gy, Wilcoxon rank-sum p = 0.009) were lower with ML planning versus manual planning, respectively. Doses to other structures, including hippocampi, cochlea, pituitary and hypothalamus were not statistically different.

CONCLUSION

In this prospective study with blinded oncologist evaluation, ML-assisted RT planning for primary CNS tumors was faster than manual planning, and produced a very high rate of acceptable plans with similar or superior OAR sparing. Future work will be undertaken to iteratively refine the ML model using the preferred cases from this study.

Dose Reductions to Critical Brain Organs-at-Risk and Better Cognition in Children with Medulloblastoma Receiving Proton Therapy

PURPOSE/OBJECTIVE(S)

Our group previously demonstrated an improvement in cognition among children with medulloblastoma treated with proton therapy, as compared to photon therapy. However, the reason for this cognitive improvement was unclear. In this study, our aim was to determine whether dose to critical brain structures acted as a mediator of improved cognition in patients treated with proton therapy.

MATERIALS/METHODS

In this retrospective study, a cohort of 75 children with medulloblastoma from two institutions was assembled (39 photon, 36 proton). Included patients were treated with similar radiation and cognitive follow-up protocols. Study endpoints were verbal comprehension (VCI), perceptual reasoning (PRI), working memory (WMI), processing speed (PSI) indices and full-scale IQ (FSIQ). Brain structures were segmented and dose comparisons by RT modality were compared using independent t-tests. Linear mixed effects models with random intercepts were created to evaluate cognitive endpoints using R version 4.2.2.

RESULTS

Median follow-up from RT to last cognitive assessment was 4.8 years. Total dose, including RT boost, was slightly lower in the proton cohort than the photon cohort (mean, 54.6 Gy vs. 56.1 Gy, respectively, p < 0.001). Eleven children (31%) treated with proton therapy received 36 Gy CSI, while 6 children (15%) treated with photon therapy received 36 Gy CSI (p = 0.07). Children treated with proton therapy had reduced total doses to the brain (mean, D40), left and right temporal lobes (mean, D40, D50), and left and right hippocampi (mean, D40, D50 - see Table). After adjustment for age at RT and posterior fossa syndrome, higher whole brain mean dose and time since RT were associated with greater decrease in VCI (p = 0.033), higher left temporal D50 and time since RT with greater decrease in PRI (p = 0.031), higher whole brain D40 and time since RT with greater decrease in PSI (p < 0.001) and FSIQ (p = 0.030).

CONCLUSION

Our study demonstrates that proton therapy for patients with medulloblastoma reduces dose to normal brain tissues, which is associated with better intellectual outcomes. Children with medulloblastoma who undergo RT should be treated with proton therapy, if available.

Oligometastasis in Prostate Cancer: Can We Learn from Those "Excluded" from a Phase 2 Trial?

We conducted and previously published a phase 2 trial of metastasis-directed therapy (MDT) in men with recurrence of prostate cancer at a low prostate-specific antigen level following radical prostatectomy and postoperative radiotherapy. All patients had negative conventional imaging and underwent prostate-specific membrane antigen (PSMA) positron emission tomography (PET). Patients without visible disease (n = 16) or with metastatic disease not amenable to MDT (n = 19) were excluded from the interventional study. The remaining patients with disease visible on PSMA-PET received MDT (n = 37). We analyzed all three groups to identify distinct phenotypes in the era of molecular imaging-based characterization of recurrent disease. Median follow up was 37 mo (interquartile range 27.5-43.0). There was no significant difference in time to the development of metastasis on conventional imaging among the groups; however, castrate-resistant prostate cancer-free survival was significantly shorter for patients with PSMA-avid disease not amenable to MDT (p = 0.047). Our findings suggest that PSMA-PET findings can help in discriminating diverging clinical phenotypes among men with disease recurrence and negative conventional imaging after local therapies with curative intent. There is a pressing need for better characterization of this rapidly growing population of patients with recurrent disease defined by PSMA-PET to derive robust selection criteria and outcome definitions for ongoing and future studies.

Patient summary

In men with prostate cancer with rising PSA levels following surgery and radiation, a newer type of scan called PSMA-PET (prostate-specific membrane antigen positron emission tomography) can be used to characterize and differentiate the patterns of recurrence, and inform future cancer outcomes.

SPCR-04 EFFECTS OF BRAIN METASTASES ON NEUROCOGNITIVE FUNCTION: BASELINE RESULTS OF A LONGITUDINAL TRIAL

PURPOSE

Neurocognitive dysfunction is common in patients with advanced metastatic cancer. The contribution of brain metastases (BrMets) to neurocognitive outcomes is uncertain. We examined the impact of BrMets on cognitive outcomes before CNS-directed treatment and compared findings to patients with advanced metastatic cancer without BrMets. Here we present results from an ongoing prospective, longitudinal study.

METHODS

English-speaking adults followed at the brain metastases and lung cancer clinics underwent neurocognitive testing using a standardized battery (prior to cranial radiotherapy, if applicable), with follow-up assessments 3, 6, 9, 12, 18, and 24 months later. We calculated z-scores and impairment rates for composite neurocognitive function and memory, attention/working memory, processing speed and executive function domains. Impairment was defined according to International Cancer and Cognition Task Force criteria.

RESULTS

78 patients with BrMets (50% female; mean age (SD):61(11) years) and 28 patients with metastatic non-small cell lung cancer (mNSCLC) with no known BrMets (71% female; age 67(9) years) were included. Baseline neurocognitive composite scores were impaired in both groups (BrMets: 61.5%; nonBrMets: 60.7%). Impairment rates varied between groups and across domains (BrMets vs nonBrMets: memory: 35.9%vs25.0%; attention/working memory: 35.8%vs21.4%; processing speed: 10.3%vs7.1%; executive function: 44.0%vs35.7%). Subgroup comparisons between BrMets patients with mNSCLC (N=29) and mNSCLC patients without BrMets, none of whom had targetable mutations, revealed no differences in impairment rates, but BrMets patients had slower processing speed than nonBrMets patients (mean(SD): -0.6(1.4) vs -0.1(1.9); Wilcoxon signed-rank test, p = 0.043).

CONCLUSION

Neurocognitive impairment in patients with advanced cancers is common. Our preliminary findings demonstrate no clear difference in cognitive outcomes between patients with BrMets and those with advanced metastatic disease not involving the brain. Our work examining how neurocognitive outcomes evolve over time in patients with and without BrMets, and demographic, disease, and treatment variables associated with those outcomes, is ongoing.

Validation of Optical Coherence Tomography Retinal Segmentation in Neurodegenerative Disease

Purpose

This study assessed agreement between an automated spectral-domain optical coherence tomography (SD-OCT) retinal segmentation software and manually corrected segmentation to validate its use in a prospective clinical study of neurodegenerative diseases (NDD).

Methods

The sample comprised 30 subjects with NDD, including vascular cognitive impairment, frontotemporal dementia, Parkinson's disease, and Alzheimer's disease. Macular SD-OCT scans were acquired and segmented using Heidelberg Spectralis. For the central foveal B scan of each eye, eight segmentation lines were examined to determine the proportion of each line that the software erroneously delineated. Errors in four lines were manually corrected in all B scans spanning a 6-mm circle centered on the foveola. Mean volume and thickness measurements for four retinal layers (total retina, retinal nerve fiber layer [RNFL], inner retinal layers, and outer retinal layers) were obtained before and after correction.

Results

The outer plexiform layer line had one of the lowest mean error ratios (2%), while RNFL had the highest (23%). Agreement between automated software and trained observer was excellent (ICC > 0.98) for retinal thickness and volume of all layers. Mean volume differences between software and observers for the four layers ranged from −0.003 to 0.006 mm³. Mean thickness differences ranged from −1.855 to 1.859 μm.

Conclusions

Despite occasional small errors in software-generated retinal sublayer segmentation, agreement was excellent between software-derived and observer-corrected mean volume and thickness sublayer measurements.

Translational Relevance

Automated SD-OCT segmentation software generates valid measurements of retinal layer volume and thickness in NDD subjects, thereby avoiding the need to manually correct nonobvious delineation errors.