Amyloid Positron Emission Tomography and Subsequent Health Care Use Among Medicare Beneficiaries With Mild Cognitive Impairment or Dementia

Importance

Results of amyloid positron emission tomography (PET) have been shown to change the management of patients with mild cognitive impairment (MCI) or dementia who meet Appropriate Use Criteria (AUC).

Objective

To determine if amyloid PET is associated with reduced hospitalizations and emergency department (ED) visits over 12 months in patients with MCI or dementia.

Design, Setting, and Participants

This nonrandomized controlled trial analyzed participants in the Imaging Dementia-Evidence for Amyloid Scanning (IDEAS) study, an open-label, multisite, longitudinal study that enrolled participants between February 2016 and December 2017 and followed up through December 2018. These participants were recruited at 595 clinical sites that provide specialty memory care across the US. Eligible participants were Medicare beneficiaries 65 years or older with a diagnosis of MCI or dementia within the past 24 months who met published AUC for amyloid PET. Each IDEAS study participant was matched to a control Medicare beneficiary who had not undergone amyloid PET. Data analysis was conducted on December 13, 2022.

Exposure

Participants underwent amyloid PET at imaging centers.

Main Outcomes and Measures

The primary end points were the proportions of patients with 12-month inpatient hospital admissions and ED visits. One of 4 secondary end points was the rate of hospitalizations and rate of ED visits in participants with positive vs negative amyloid PET results. Health care use was ascertained from Medicare claims data.

Results

The 2 cohorts (IDEAS study participants and controls) each comprised 12 684 adults, including 6467 females (51.0%) with a median (IQR) age of 77 (73-81) years. Over 12 months, 24.0% of the IDEAS study participants were hospitalized, compared with 25.1% of the matched control cohort, for a relative reduction of -4.49% (97.5% CI, -9.09% to 0.34%). The 12-month ED visit rates were nearly identical between the 2 cohorts (44.8% in both IDEAS study and control cohorts) for a relative reduction of -0.12% (97.5% CI, -3.19% to 3.05%). Both outcomes fell short of the prespecified effect size of 10% or greater relative reduction. Overall, 1467 of 6848 participants (21.4%) with positive amyloid PET scans were hospitalized within 12 months compared with 1081 of 4209 participants (25.7%) with negative amyloid PET scans (adjusted odds ratio, 0.83; 95% CI, 0.78-0.89).

Conclusions and Relevance

Results of this nonrandomized controlled trial showed that use of amyloid PET was not associated with a significant reduction in 12-month hospitalizations or ED visits. Rates of hospitalization were lower in patients with positive vs negative amyloid PET results.

Utilization of Diagnostic Procedures After Lung Cancer Screening in the National Lung Screening Trial

OBJECTIVE

To examine utilization patterns of diagnostic procedures after lung cancer screening among participants enrolled in the National Lung Screening Trial.

METHODS

Using a sample of National Lung Screening Trial participants with abstracted medical records, we assessed utilization of imaging, invasive, and surgical procedures after lung cancer screening. Missing data were imputed using multiple imputation by chained equations. For each procedure type, we examined utilization within a year after the screening or until the next screen, whichever came first, across arms (low-dose CT [LDCT] versus chest X-ray [CXR]) and by screening results. We also explored factors associated with having these procedures using multivariable negative binomial regressions.

RESULTS

After baseline screening, our sample had 176.5 and 46.7 procedures per 100 person-years for those with a false-positive and negative result, respectively. Invasive and surgical procedures were relatively infrequent. Among those who screened positive, follow-up imaging and invasive procedures were 25% and 34% less frequent in those screened with LDCT, compared with CXR. Postscreening utilization of invasive and surgical procedures was 37% and 34% lower at the first incidence screen compared with baseline. Participants with positive results at baseline were six times more likely to undergo additional imaging than those with normal findings.

DISCUSSION

Use of imaging and invasive procedures to evaluate abnormal findings varied by screening modality, with a lower rate for LDCT than CXR. Invasive and surgical workup were less prevalent after subsequent screening examinations compared with baseline screening. Utilization was associated with older age but not gender, race or ethnicity, insurance status, or income.

Impact of Muscle Measures on Outcome in Patients Receiving Endocrine Therapy for Metastatic Breast Cancer: Analysis of ECOG-ACRIN E2112

BACKGROUND

Observational data investigating the relationship between body habitus and outcomes in breast cancer have been variable and inconsistent, largely centered in the curative setting and focused on weight-based metrics. This study evaluated the impact of muscle measures on outcomes in patients with metastatic breast cancer receiving endocrine-based therapy.

METHODS

Baseline CT scans were collected from ECOG-ACRIN E2112, a randomized phase III placebo-controlled study of exemestane with or without entinostat. A CT cross-sectional image at the L3 level was extracted to obtain skeletal muscle mass and attenuation. Low muscle mass (LMM) was defined as skeletal muscle index <41 cm2/m2 and low muscle attenuation (LMA) as muscle density <25 HU or <33 HU if overweight/obese by body mass index (BMI). Multivariable Cox proportional hazard models determined the association between LMM or LMA and progression-free survival (PFS) and overall survival (OS). Correlations between LMM, LMA, and patient-reported outcomes were determined using 2-sample t tests.

RESULTS

Analyzable CT scans and follow-up data were available for 540 of 608 patients. LMM was present in 39% (n=212) of patients and LMA in 56% (n=301). Those with LMA were more likely to have obesity and worse performance status. LMM was not associated with survival (PFS hazard ratio [HR]: 1.13, P=.23; OS HR: 1.05, P=.68), nor was LMA (PFS HR: 1.01, P=.93; OS HR: 1.00, P=.99). BMI was not associated with survival. LMA, but not LMM, was associated with increased frequency of patient-reported muscle aches.

CONCLUSIONS

Both low muscle mass and density are prevalent in patients with hormone receptor-positive metastatic breast cancer. Muscle measures correlated with obesity and performance status; however, neither muscle mass nor attenuation were associated with prognosis. Further work is needed to refine body composition measurements and select optimal cutoffs with meaningful endpoints in specific breast cancer populations, particularly those living with metastatic disease.

Estimating the area under the ROC curve when transporting a prediction model to a target population

We propose methods for estimating the area under the receiver operating characteristic (ROC) curve (AUC) of a prediction model in a target population that differs from the source population that provided the data used for original model development. If covariates that are associated with model performance, as measured by the AUC, have a different distribution in the source and target populations, then AUC estimators that only use data from the source population will not reflect model performance in the target population. Here, we provide identification results for the AUC in the target population when outcome and covariate data are available from the sample of the source population, but only covariate data are available from the sample of the target population. In this setting, we propose three estimators for the AUC in the target population and show that they are consistent and asymptotically normal. We evaluate the finite-sample performance of the estimators using simulations and use them to estimate the AUC in a nationally representative target population from the National Health and Nutrition Examination Survey for a lung cancer risk prediction model developed using source population data from the National Lung Screening Trial.

Survival analysis using deep learning with medical imaging

There is widespread interest in using deep learning to build prediction models for medical imaging data. These deep learning methods capture the local structure of the image and require no manual feature extraction. Despite the importance of modeling survival in the context of medical data analysis, research on deep learning methods for modeling the relationship of imaging and time-to-event data is still under-developed. We provide an overview of deep learning methods for time-to-event outcomes and compare several deep learning methods to Cox model based methods through the analysis of a histology dataset of gliomas.

Role of calibration in uncertainty-based referral for deep learning

The uncertainty in predictions from deep neural network analysis of medical imaging is challenging to assess but potentially important to include in subsequent decision-making. Using data from diabetic retinopathy detection, we present an empirical evaluation of the role of model calibration in uncertainty-based referral, an approach that prioritizes referral of observations based on the magnitude of a measure of uncertainty. We consider several configurations of network architecture, methods for uncertainty estimation, and training data size. We identify a strong relationship between the effectiveness of uncertainty-based referral and having a well-calibrated model. This is especially relevant as complex deep neural networks tend to have high calibration errors. Finally, we show that post-calibration of the neural network helps uncertainty-based referral with identifying hard-to-classify observations.

Abstract P3-05-26: Association of muscle mass and density with outcomes in patients with ER positive metastatic breast cancer: correlative analysis of ECOG-ACRIN 2112

Introduction: Observational data investigating the relationship between body habitus and survival or toxicity in breast cancer has been largely centered in the curative setting and focused on weight- based metrics, with variable and inconsistent results. Muscle is a large, active endocrine organ that affects physical function, drug metabolism, inflammation, and quality of life, but is not adequately measured by body weight alone. Very few studies have evaluated muscle measures in metastatic breast cancer (MBC) and have been focused on patients receiving cytotoxic chemotherapy. Here, we evaluate the impact of muscle mass and muscle density measured on CT scan on outcomes in patients with MBC receiving endocrine- based therapy. Methods: Baseline CT scans done at the time of study enrollment were centrally collected from participants in ECOG-ACRIN E2112, a randomized phase III study of exemestane with or without entinostat in MBC, which ultimately did not impact survival. A transverse cut at the L3 level was extracted and processed using semi-automated SliceOmatic software (Tomovision) by two independent investigators to obtain total body skeletal muscle mass and muscle attenuation. Low muscle mass was defined as skeletal muscle index (SMI, lean muscle area/height, cm2/m2) less than 41 and low skeletal muscle attenuation (SMA) was defined as average muscle density less than 41 HU, or less than 33 HU if the patient is overweight or obese by BMI. Chi-square tests were used to determine the association between SMI and SMA and other clinical characteristics, including body weight, race, and performance status. Multivariable Cox proportional hazard models were used to determine the association between low SMI or low SMA and overall survival (OS), progression free survival (PFS), and patient- reported outcomes. Results: Of the 608 patients randomized in E2112, 546 had analyzable CT scans and follow up data available. 45% (n=246) of participants had obesity by BMI (≥30); 39% (n=212) had low SMI and 56% (n=305) had low SMA. Obese patients were more likely to have higher SMI (p&lt; 0.001); however, 9.5% (n=52) of the study population had both obesity and low SMI. Low SMA was associated with higher rate of obesity and worse performance status (p&lt; 0.001), consistent with muscle quality being a predictor of functional status. Low SMI was not associated with survival outcomes (OS HR 1.04 95%CI 0.83-1.30, PFS HR 1.12 95% CI 0.92-1.36), nor was low SMA (OS HR 1.02 95%CI 0.81-1.28; PFS HR 1.02 95%CI 0.84-1.23). In addition, BMI was not related to survival outcomes. Conclusions: Low muscle mass and low muscle density are prevalent in estrogen receptor positive MBC patients. Muscle measures correlated with obesity and performance status; however, neither low SMI nor low SMA were associated with worse prognosis in this population. Further work is needed to refine body composition measurements and select optimal cutoffs and meaningful endpoints in specific breast cancer populations, particularly in those living with metastatic disease.

Citation Format: Tarah J. Ballinger, Gloria Xue, Helga S. Marques, Constantine Gatsonis, Richard Hoffman, Kathy D. Miller, Fengmin Zhao, Joseph Sparano, Roisin Connolly. Association of muscle mass and density with outcomes in patients with ER positive metastatic breast cancer: correlative analysis of ECOG-ACRIN 2112 [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-05-26.

Transporting a Prediction Model for Use in a New Target Population

We considered methods for transporting a prediction model for use in a new target population, both when outcome and covariate data for model development are available from a source population that has a different covariate distribution compared with the target population and when covariate data (but not outcome data) are available from the target population. We discuss how to tailor the prediction model to account for differences in the data distribution between the source population and the target population. We also discuss how to assess the model's performance (e.g., by estimating the mean squared prediction error) in the target population. We provide identifiability results for measures of model performance in the target population for a potentially misspecified prediction model under a sampling design where the source and the target population samples are obtained separately. We introduce the concept of prediction error modifiers that can be used to reason about tailoring measures of model performance to the target population. We illustrate the methods in simulated data and apply them to transport a prediction model for lung cancer diagnosis from the National Lung Screening Trial to the nationally representative target population of trial-eligible individuals in the National Health and Nutrition Examination Survey.

Racial and Ethnic Differences in Amyloid PET Positivity in Individuals With Mild Cognitive Impairment or Dementia: A Secondary Analysis of the Imaging Dementia-Evidence for Amyloid Scanning (IDEAS) Cohort Study

Importance

Racial and ethnic groups with higher rates of clinical Alzheimer disease (AD) are underrepresented in studies of AD biomarkers, including amyloid positron emission tomography (PET).

Objective

To compare amyloid PET positivity among a diverse cohort of individuals with mild cognitive impairment (MCI) or dementia.

Design, Setting, and Participants

Secondary analysis of the Imaging Dementia-Evidence for Amyloid Scanning (IDEAS), a single-arm multisite cohort study of Medicare beneficiaries who met appropriate-use criteria for amyloid PET imaging between February 2016 and September 2017 with follow-up through January 2018. Data were analyzed between April 2020 and January 2022. This study used 2 approaches: the McNemar test to compare amyloid PET positivity proportions between matched racial and ethnic groups and multivariable logistic regression to assess the odds of having a positive amyloid PET scan. IDEAS enrolled participants at 595 US dementia specialist practices. A total of 21 949 were enrolled and 4842 (22%) were excluded from the present analysis due to protocol violations, not receiving an amyloid PET scan, not having a positive or negative scan, or because of small numbers in some subgroups.

Exposures

In the IDEAS study, participants underwent a single amyloid PET scan.

Main Outcomes and Measures

The main outcomes were amyloid PET positivity proportions and odds.

Results

Data from 17 107 individuals (321 Asian, 635 Black, 829 Hispanic, and 15 322 White) with MCI or dementia and amyloid PET were analyzed between April 2020 and January 2022. The median (range) age of participants was 75 (65-105) years; 8769 participants (51.3%) were female and 8338 (48.7%) were male. In the optimal 1:1 matching analysis (n = 3154), White participants had a greater proportion of positive amyloid PET scans compared with Asian participants (181 of 313; 57.8%; 95% CI, 52.3-63.2 vs 142 of 313; 45.4%; 95% CI, 39.9-50.9, respectively; P = .001) and Hispanic participants (482 of 780; 61.8%; 95% CI, 58.3-65.1 vs 425 of 780; 54.5%; 95% CI, 51.0-58.0, respectively; P = .003) but not Black participants (359 of 615; 58.4%; 95% CI, 54.4-62.2 vs 333 of 615; 54.1%; 95% CI, 50.2-58.0, respectively; P = .13). In the adjusted model, the odds of having a positive amyloid PET scan were lower for Asian participants (odds ratio [OR], 0.47; 95% CI, 0.37-0.59; P < .001), Black participants (OR, 0.71; 95% CI, 0.60-0.84; P < .001), and Hispanic participants (OR, 0.68; 95% CI, 0.59-0.79; P < .001) compared with White participants.

Conclusions and Relevance

Racial and ethnic differences found in amyloid PET positivity among individuals with MCI and dementia in this study may indicate differences in underlying etiology of cognitive impairment and guide future treatment and prevention approaches.

Adjusting the TMIST study design to accommodate slower than expected accrual: ECOG-ACRIN EA1151

TPS10614

Background: The ECOG-ACRIN Tomosynthesis Mammographic Imaging Screening Trial (TMIST), which opened in 2017, is a randomized trial designed to assess whether Tomosynthesis Mammography (TM) should replace Digital Mammography (DM) for breast cancer screening. It is hypothesized that women assigned to TM for 3-5 screening rounds will have fewer advanced breast cancers than the women assigned to DM. Advanced cancers are those that have distant metastases or positive nodes, are invasive tumors greater than or equal to 2.0 cm in size, or are invasive tumors greater than 1.0 cm in size that are triple negative or HER 2+. The initially planned enrollment of 164,946 women was due to be completed by the end of 2020, with follow-up concluded by 2025. There were substantial challenges in meeting this timeline, including the organizational and funding structure of the NCI National Clinical Trials Network which is dependent upon sites using their existing staffing resources (not always readily available at the time of study activation). This led to longer than anticipated start of enrollment for most interested sites and lower than anticipated annual enrollment per participating site based ultimately on the staffing support that could be allocated to manage TMIST. In addition, research staffing shortages and periodic research operations closures due to COVID-19 have also impacted enrolling TMIST sites, though unevenly, since the start of the pandemic. Enrollment plateaued at approximately 2,100 subjects per month by the end of 2020. With that accrual rate expected, the trial design was modified to reduce the sample size so that the study could be completed by 2027. Methods: With the approval of the NCI CIRB, we changed how the primary endpoint measure for TMIST is assessed from the number of advanced cancers that occur by 4.5 years after randomization to the time from randomization to occurrence of advanced cancers. All advanced cancers occurring within 7 years of randomization are now included and all participants followed for at least three years. In addition, the power of the study of the study was modified from 0.9 to 0.85, while the originally assumed effect size at 4.5 years was retained These changes allowed a reduction of sample size to 128,905, with subject recruitment projected to end in 2024. As of February 14, 2022, there are 125 sites open, 114 in the U.S. and 11 in other countries, with an additional 31 sites planning to open. As of February 14, 2022, a total of 63,845 women have been enrolled in the trial worldwide at 115 sites, with 20% of US participants self-identifying as belonging to minority racial and ethnic groups and 70% consenting to optional blood and/or buccal cell collection. Clinical trial information: NCT03233191.

A randomized phase II study of gemcitabine and nab-paclitaxel compared with 5-fluorouracil, leucovorin, and liposomal irinotecan in older patients with treatment-naïve metastatic pancreatic cancer (GIANT): ECOG-ACRIN EA2186—Trials in progress

TPS4185

Background: Evidence-based data is lacking to guide the care of older adults with newly diagnosed metastatic pancreatic cancer (mPCA). As a result, treatment approach and the selection of chemotherapy regimens are often extrapolated from data from younger patients. Furthermore, vulnerable older adults are often treated with dose adjusted regimens with limited data to support this practice. EA2186 is a phase II randomized controlled trial, and the first prospective study aiming to define the optimal treatment approach of vulnerable older adults with newly diagnosed mPCA. Methods: Patients aged 70 years and over with histologically confirmed pancreatic adenocarcinoma, evidence of metastatic disease, ECOG PS 0-2 and adequate organ function, who are considered vulnerable are eligible for this trial (accrual target 184). This study utilizes a screening geriatric assessment which characterize patients as fit, vulnerable or frail by evaluating functional status, cognition and co-morbidities. Vulnerable patients according to this screening assessment are those with mild abnormalities in functional status, comorbidities and/or cognition, or older than 80 years of age. Those patients will be randomized to receive either modified Gemcitabine/Nab-Paclitaxel or dose-reduced 5-Fluorouracil Leucovorin and Liposomal Irinotecan every 2 weeks. A comprehensive geriatric assessment (GA) and quality of life (QOL) evaluation are completed prior to initiation of therapy for all randomized patients. Follow up will continue until disease progression or withdrawal, with repeated GA and QOL assessments at each disease evaluation. Overall survival is the primary objective, with secondary objectives including progression free survival, and response rate. Enrolled patients will be stratified by age 70-74 vs ≥75, and ECOG PS 0-1 vs 2. Additional endpoints of interest for older adults include: evaluation of risk factors identified through GA, and capturing toxicities of interest for this patient population (i.e. hospitalization, deterioration in PS, and falls). Correlative studies include assessment of pro-inflammatory biomarkers or aging in the blood (IL-6 and CRP) as well as imaging evaluation of sarcopenia and body composition as predictors of treatment tolerance. Clinical trial information: NCT04233866.

Assessment of a Plasma Amyloid Probability Score to Estimate Amyloid Positron Emission Tomography Findings Among Adults With Cognitive Impairment

IMPORTANCE

The diagnostic evaluation for Alzheimer disease may be improved by a blood-based diagnostic test identifying presence of brain amyloid plaque pathology.

OBJECTIVE

To determine the clinical performance associated with a diagnostic algorithm incorporating plasma amyloid-β (Aβ) 42:40 ratio, patient age, and apoE proteotype to identify brain amyloid status.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study includes analysis from 2 independent cross-sectional cohort studies: the discovery cohort of the Plasma Test for Amyloidosis Risk Screening (PARIS) study, a prospective add-on to the Imaging Dementia-Evidence for Amyloid Scanning study, including 249 patients from 2018 to 2019, and MissionAD, a dataset of 437 biobanked patient samples obtained at screenings during 2016 to 2019. Data were analyzed from May to November 2020.

EXPOSURES

Amyloid detected in blood and by positron emission tomography (PET) imaging.

MAIN OUTCOMES AND MEASURES

The main outcome was the diagnostic performance of plasma Aβ42:40 ratio, together with apoE proteotype and age, for identifying amyloid PET status, assessed by accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC).

RESULTS

All 686 participants (mean [SD] age 73.2 [6.3] years; 368 [53.6%] men; 378 participants [55.1%] with amyloid PET findings) had symptoms of mild cognitive impairment or mild dementia. The AUC of plasma Aβ42:40 ratio for PARIS was 0.79 (95% CI, 0.73-0.85) and 0.86 (95% CI, 0.82-0.89) for MissionAD. Ratio cutoffs for Aβ42:40 based on the Youden index were similar between cohorts (PARIS: 0.089; MissionAD: 0.092). A logistic regression model (LRM) incorporating Aβ42:40 ratio, apoE proteotype, and age improved diagnostic performance within each cohort (PARIS: AUC, 0.86 [95% CI, 0.81-0.91]; MissionAD: AUC, 0.89 [95% CI, 0.86-0.92]), and overall accuracy was 78% (95% CI, 72%-83%) for PARIS and 83% (95% CI, 79%-86%) for MissionAD. The model developed on the prospectively collected samples from PARIS performed well on the MissionAD samples (AUC, 0.88 [95% CI, 0.84-0.91]; accuracy, 78% [95% CI, 74%-82%]). Training the LRM on combined cohorts yielded an AUC of 0.88 (95% CI, 0.85-0.91) and accuracy of 81% (95% CI, 78%-84%). The output of this LRM is the Amyloid Probability Score (APS). For clinical use, 2 APS cutoff values were established yielding 3 categories, with low, intermediate, and high likelihood of brain amyloid plaque pathology.

CONCLUSIONS AND RELEVANCE

These findings suggest that this blood biomarker test could allow for distinguishing individuals with brain amyloid-positive PET findings from individuals with amyloid-negative PET findings and serve as an aid for Alzheimer disease diagnosis.

rPOP: Robust PET-only processing of community acquired heterogeneous amyloid-PET data

The reference standard for amyloid-PET quantification requires structural MRI (sMRI) for preprocessing in both multi-site research studies and clinical trials. Here we describe rPOP (robust PET-Only Processing), a MATLAB-based MRI-free pipeline implementing non-linear warping and differential smoothing of amyloid-PET scans performed with any of the FDA-approved radiotracers (¹⁸F-florbetapir/FBP, ¹⁸F-florbetaben/FBB or ¹⁸F-flutemetamol/FLUTE). Each image undergoes spatial normalization based on weighted PET templates and data-driven differential smoothing, then allowing users to perform their quantification of choice. Prior to normalization, users can choose whether to automatically reset the origin of the image to the center of mass or proceed with the pipeline with the image as it is. We validate rPOP with n = 740 (514 FBP, 182 FBB, 44 FLUTE) amyloid-PET scans from the Imaging Dementia-Evidence for Amyloid Scanning - Brain Health Registry sub-study (IDEAS-BHR) and n = 1,518 scans from the Alzheimer's Disease Neuroimaging Initiative (n = 1,249 FBP, n = 269 FBB), including heterogeneous acquisition and reconstruction protocols. After running rPOP, a standard quantification to extract Standardized Uptake Value ratios and the respective Centiloids conversion was performed. rPOP-based amyloid status (using an independent pathology-based threshold of ≥24.4 Centiloid units) was compared with either local visual reads (IDEAS-BHR, n = 663 with complete valid data and reads available) or with amyloid status derived from an MRI-based PET processing pipeline (ADNI, thresholds of >20/>18 Centiloids for FBP/FBB). Finally, within the ADNI dataset, we tested the linear associations between rPOP- and MRI-based Centiloid values. rPOP achieved accurate warping for N = 2,233/2,258 (98.9%) in the first pass. Of the N = 25 warping failures, 24 were rescued with manual reorientation and origin reset prior to warping. We observed high concordance between rPOP-based amyloid status and both visual reads (IDEAS-BHR, Cohen's k = 0.72 [0.7-0.74], ∼86% concordance) or MRI-pipeline based amyloid status (ADNI, k = 0.88 [0.87-0.89], ∼94% concordance). rPOP- and MRI-pipeline based Centiloids were strongly linearly related (R²:0.95, p<0.001), with this association being significantly modulated by estimated PET resolution (β= -0.016, p<0.001). rPOP provides reliable MRI-free amyloid-PET warping and quantification, leveraging widely available software and only requiring an attenuation-corrected amyloid-PET image as input. The rPOP pipeline enables the comparison and merging of heterogeneous datasets and is publicly available at https://github.com/leoiacca/rPOP.

The Longitudinal Early-onset Alzheimer's Disease Study (LEADS): Framework and methodology

Patients with early-onset Alzheimer's disease (EOAD) are commonly excluded from large-scale observational and therapeutic studies due to their young age, atypical presentation, or absence of pathogenic mutations. The goals of the Longitudinal EOAD Study (LEADS) are to (1) define the clinical, imaging, and fluid biomarker characteristics of EOAD; (2) develop sensitive cognitive and biomarker measures for future clinical and research use; and (3) establish a trial-ready network. LEADS will follow 400 amyloid beta (Aβ)-positive EOAD, 200 Aβ-negative EOnonAD that meet National Institute on Aging-Alzheimer's Association (NIA-AA) criteria for mild cognitive impairment (MCI) or AD dementia, and 100 age-matched controls. Participants will undergo clinical and cognitive assessments, magnetic resonance imaging (MRI), [18 F]Florbetaben and [18 F]Flortaucipir positron emission tomography (PET), lumbar puncture, and blood draw for DNA, RNA, plasma, serum and peripheral blood mononuclear cells, and post-mortem assessment. To develop more effective AD treatments, scientists need to understand the genetic, biological, and clinical processes involved in EOAD. LEADS will develop a public resource that will enable future planning and implementation of EOAD clinical trials.

CLRM-07. INCREASING EFFICIENCY IN EARLY PHASE MULTICENTER IMAGING BIOMARKER TRIALS: EMERGING STRATEGIES FROM THE GABLE (GLIOBLASTOMA ACCELERATED BIOMARKER LEARNING ENVIRONMENT) TRIAL

Validated biomarkers that more accurately predict prognosis and/or measure disease burden in patients with high-grade gliomas would help triage which treatment strategies are most promising for evaluation in Phase III multicenter trials. Multicenter trials to evaluate imaging biomarkers in this group face particular challenges; these trials have historically been slow to accrue and have not recently succeeded in validating new imaging biomarkers useful in treatment development. Due to variability in image acquisition protocols, scanner hardware, image analysis, and interpretive schemes, promising results obtained in single centers are poor predictors of success in the multicenter setting. Multicenter preliminary data to support further evaluation of imaging biomarkers is rarely available. The need for more efficient trial designs that bring multicenter data earlier into the process of biomarker development has become increasingly clear. In this presentation, the planning process within ECOG-ACRIN’s Brain Tumor Working Group for a platform multicenter trial called GABLE (Glioblastoma Accelerated Biomarker Learning Environment trial) designed to evaluate biomarkers for distinguishing pseudoprogression from true progression in patients with newly diagnosed GBM is described. In our planning process, it was determined that efficiencies can be gained from evaluating multiple biomarker types in parallel rather than serially; in the context of the proposed trial, not only conventional imaging biomarkers but plasma biomarkers and radiomic biomarkers can be evaluated simultaneously. Patient tolerance limits the feasibility of evaluating multiple non-standard-of-care imaging biomarkers in parallel. For this group of biomarkers, a “fast-switching” serial evaluation strategy using multiple interim analyses was developed to triage out biomarkers unlikely to succeed in identifying patient groups with clinically significant differences in median survival. For biomarker triage, an endpoint of event-free survival (events of either death or NANO progression) was proposed. Simulations were used to evaluate alpha and beta error using this evaluation strategy.

Preoperative Breast MRI for Newly Diagnosed Ductal Carcinoma in Situ: Imaging Features and Performance in a Multicenter Setting (ECOG-ACRIN E4112 Trial)

Background There are limited data from clinical trials describing preoperative MRI features and performance in the evaluation of mammographically detected ductal carcinoma in situ (DCIS). Purpose To report qualitative MRI features of DCIS, MRI performance in the identification of additional disease, and associations of imaging features with pathologic, genomic, and surgical outcomes from the Eastern Cooperative Oncology Group-American College of Radiology Imaging Network (ECOG-ACRIN) E4112 trial. Materials and Methods Secondary analyses of a multicenter prospective clinical trial from the ECOG-ACRIN Cancer Research Group included women with DCIS diagnosed with conventional imaging techniques (mammography and US), confirmed via core-needle biopsy (CNB), and enrolled between March 2015 and April 2016 who were candidates for wide local excision (WLE) based on conventional imaging and clinical examination results. DCIS MRI features and pathologic features from CNB and excision were recorded. Each woman without invasive upgrade of the index DCIS at WLE received a 12-gene DCIS score. MRI performance metrics were calculated. Associations of imaging features with invasive upgrade, dichotomized DCIS score (<39 vs ≥39), and single WLE success were estimated in uni- and multivariable analyses. Results Among 339 women (median age, 60 years; interquartile range, 51-66 years), most DCIS cases showed nonmass enhancement (NME) (195 of 339 [58%]) on MRI scans with larger median size than on mammograms (19 mm vs 12 mm; P < .001). Positive predictive value of MRI-prompted CNBs was 32% (21 of 66) (95% CI: 22, 44), yielding an additional cancer detection rate of 6.2% (21 of 339) (95% CI: 4.1, 9.3). MRI false-positive rate was 14.2% (45 of 318) (95% CI: 10.7, 18.4). No imaging features were associated with invasive upgrade or DCIS score (P = .05 to P = .95). Smaller size and focal NME distribution at MRI were linked to single WLE success (P < .001). Conclusion Preoperative MRI depicted ductal carcinoma in situ (DCIS) diagnosed with conventional imaging most commonly as nonmass enhancement, with larger median span than mammography, and additional cancer detection rate of 6.2%. MRI features of this subset of DCIS did not enable prediction of pathologic or genomic outcomes. Clinical trial registration no. NCT02352883 © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Kuhl in this issue.

Predictors of surgery preference and quality of life in DCIS after breast MRI: A trial of the ECOG-ACRIN Cancer Research Group (E4112)

6564

Background: Management of ductal carcinoma in situ (DCIS) remains variable, requiring an understanding of patient preferences and concerns to enhance the treatment decision-making process. Pre-operative MRI and surgeon recommendation can further inform surgery choice. Quality of life (QoL) is also an important consideration in treatment decision-making. The aims of this study were to assess patients’ treatment preferences before and after MRI and surgeon consultation, concordance between treatment preference and surgery received, and trends in health-related QoL (HRQL) among a prospective cohort of women newly diagnosed with DCIS. Methods: A prospective nonrandomized clinical trial by the ECOG-ACRIN Cancer Research Group (E4112) enrolled women diagnosed with unilateral DCIS from 75 institutions between March 2015 and April 2016. Participants underwent either wide local excision (WLE) or mastectomy. Surveys queried patient-reported outcomes (PRO) including treatment preference and concerns, and HRQL before and after surgery. Logistic regression models were used to associate surgery preference and actual surgery received with demographic, clinical and PRO data. Change from baseline in HRQL was assessed using linear regression. Results: At study entry, age (OR 0.39, per 5-year increment, 95%CI, 0.21-0.75; p = 0.005) and treatment goals related to the importance of keeping one’s breast (OR 0.51, 95%CI 0.34-0.76; p = 0.001) and removal of the breast for peace of mind (OR 1.46, 95%CI 1.09-1.95; p = 0.01) drove surgery preference for mastectomy vs. WLE. After receipt of MRI and surgeon consultation, surgery preference was primarily mediated by MRI upstaging (OR 11.18, 95%CI 3.19-39.16; p < 0.001). Only 4% of women received a type of surgery that did not match their final treatment preference. The strongest predictors of actual surgery received were MRI upstaging (OR 15.80, 95%CI 4.85-51.46) and surgeon recommendation of mastectomy (OR 4.60, 95%CI 1.52-13.94). Receipt of a single surgery was associated with significantly improved mental health from baseline to one year after definitive surgery (p = 0.02 for mastectomy; p = 0.003 for single WLE). Self-reported Black race was an independent predictor of worsened mental (p = 0.001) and physical (p = 0.04) health at one year after definitive surgery, despite no significant racial differences in baseline HRQL. Conclusions: Our findings highlight the importance of communication between providers and patients regarding treatment preferences and goals, the clinical significance of MRI findings, and the benefits/risks of available treatment options. Future research to identify modifiable factors associated with declining mental and physical health is needed to inform targeted interventions to mitigate racial disparities and enhance HRQL in patients with DCIS.

A phase II/III study of perioperative nivolumab and ipilimumab in patients (pts) with locoregional esophageal (E) and gastroesophageal junction (GEJ) adenocarcinoma: Results of a safety run-in—A trial of the ECOG-ACRIN Cancer Research Group (EA2174)

4064

Background: E/GEJ adenocarcinoma has a high mortality rate despite curative intent therapy. The use of immune checkpoint inhibition is beneficial for treatment of this cancer in the metastatic and adjuvant settings but the role of these agents in the perioperative setting remains unclear. Here we report the results of an initial safety run-in of nivolumab when given in combination with neoadjuvant chemoradiation. Methods: Pts with a localized T1N1-3M0 or T2-3N0-2M0 E/GEJ adenocarcinoma with an ECOG PS of 0-1 and whom were deemed surgical candidates for an esophagectomy by a qualified surgeon were eligible. In step 1, pts were randomized to neoadjuvant therapy with carboplatin AUC 2 and paclitaxel 50 mg/m2 intravenously (IV) weekly x 5 along with 41.4-50.4 Gy radiation without (Arm A) or with (Arm B) nivolumab 240 mg IV during weeks 1 and 3 of treatment, followed by esophagectomy. Pts underwent a second randomization (step 2) to adjuvant nivolumab 240 mg IV every 2 weeks x 12 cycles with or without ipilimumab 1 mg/kg IV every 6 weeks during cycles 1, 4, 7 and 10. For the safety run-in, 30 pts were planned for accrual to allow for 12 evaluable pts per arm. Pts were followed for safety during neoadjuvant therapy through surgery and toxicities monitored per CTCAEv5. Pre-specified early stopping rules were defined to allow halting of the trial if deemed unsafe. Planned study accrual is 278 pts. Neoadjuvant primary endpoint is pathologic complete response rate, adjuvant primary endpoint is disease-free survival. Results: A total of 31 pts were enrolled to the safety run-in element of the study (Arm A, n = 16; Arm B n = 15). Male, 94%; White, 100%; median age, 62; esophageal adenocarcinoma, 52%; GEJ, 48%. Grade (G) 3 events occurring in more than one pt on Arm A—decreased lymphocytes (n = 5). G4 events occurring on Arm A—decreased lymphocytes (n = 1). G3 events occurring in more than one pt on Arm B—decreased lymphocytes (n = 2); anemia (n = 2); leukopenia (n = 4); hypotension (n = 2). G4 events occurring on Arm B—decreased lymphocytes (n = 3); cardiac tamponade and pericardial effusion (n = 1). Cardiac events were thought to be secondary to tumor location, not neoadjuvant treatment. On Arm B, notable G3 events seen in one pt each included colonic obstruction, wound infection and esophageal anastomotic leak. Of pts who have reached the time for surgery, 12/14 pts on Arm A and 13/13 pts on Arm B have proceeded to surgery. Of pts who have completed step 1, 7/14 pts on Arm A and 8/11 pts on Arm B have registered to step 2. Conclusions: The addition of nivolumab to carboplatin, paclitaxel and radiation in the neoadjuvant setting appears to be safe with no disproportionate level of toxicity observed between the two treatment arms. Accrual to the remainder of the trial continues with 43/278 patients accrued. Clinical trial information: NCT03604991.

Engaging the radiology community in the National Clinical Trials Network: The ECOG-ACRIN TMIST experience

TPS10609

Background: ECOG-ACRIN launched the Tomosynthesis Mammographic Imaging Screening Trial (TMIST) through the National Cancer Institute’s National Clinical Trials Network (NCTN)— a network of academic medical centers, community hospitals, and private clinical practices that are committed to participating in NCI-funded clinical trials. The NCI NCTN was developed to support rapid trial start-up of NCI-funded cancer control/prevention, cancer treatment, and non-therapeutic clinical trials that occur within the institution through centralized institutional administration and shared clinical resource allocation (personnel, lab services). TMIST is a randomized clinical trial assessing two breast cancer screening imaging modalities, tomosynthesis and digital mammography, in the population of women presenting for screening mammography and therefore requires active involvement of radiology. Methods: TMIST seeks to enroll 164,946 women, ages 45 to 74 years who present for screening mammography. Because the population under evaluation are women already scheduled for screening mammography, the mammography clinic is critical to successful recruitment as well as adherence to imaging randomization assignments over a 5-year period and therefore must be actively engaged in this trial with a breast imaging radiologist championing the trial within this service. To get active engagement of breast imaging radiologists, we needed to first make them aware of TMIST. Breast imaging radiologists that were already actively involved in the NCTN received notification of the trial through the NCTN email lists. So our goal was to come up with a strategy to reach out to breast imaging radiologists that were not active members in the NCTN. This was achieved through in-person informational sessions to introduce the trial at national and international breast imaging meetings, introduction of the trial and the workings of the NCTN network to the radiology community through articles placed in American College of Radiology (ACR) newsletters, ads promoting TMIST on ACR social media platforms, and direct email by the TMIST study chair to key radiology stakeholders. As of February 15, 2021, there are 115 sites open: 106 in the U.S. and 9 internationally with an additional 54 sites planning to open. A total of 39,366 women are enrolled in the trial with two-thirds also consenting to optional blood and/or buccal cell collection. Minority populations’ participation in the trial is over 20%. A significant drop in enrollment occurred in Spring 2020 coinciding with the suspension of mammography services globally due to COVID-19 beginning mid-March 2020. Enrollment and follow-up screening visits for TMIST restarted in May 2020 and gradually ramped back up to pre-COVID totals in September 2020. Our highest monthly accrual so far occurred in November 2020 with 2,148 subjects enrolled. Clinical trial information: NCT03233191 .

Preferred reporting items for journal and conference abstracts of systematic reviews and meta-analyses of diagnostic test accuracy studies (PRISMA-DTA for Abstracts): checklist, explanation, and elaboration

For many users of the biomedical literature, abstracts may be the only source of information about a study. Hence, abstracts should allow readers to evaluate the objectives, key design features, and main results of the study. Several evaluations have shown deficiencies in the reporting of journal and conference abstracts across study designs and research fields, including systematic reviews of diagnostic test accuracy studies. Incomplete reporting compromises the value of research to key stakeholders. The authors of this article have developed a 12 item checklist of preferred reporting items for journal and conference abstracts of systematic reviews and meta-analyses of diagnostic test accuracy studies (PRISMA-DTA for Abstracts). This article presents the checklist, examples of complete reporting, and explanations for each item of PRISMA-DTA for Abstracts.

Association Between Ambient Air Pollution and Amyloid Positron Emission Tomography Positivity in Older Adults With Cognitive Impairment

Importance

Amyloid-β (Aβ) deposition is a feature of Alzheimer disease (AD) and may be promoted by exogenous factors, such as ambient air quality.

Objective

To examine the association between the likelihood of amyloid positron emission tomography (PET) scan positivity and ambient air quality in individuals with cognitive impairment.

Design, Setting, and Participants

This cross-sectional study used data from the Imaging Dementia-Evidence for Amyloid Scanning Study, which included more than 18 000 US participants with cognitive impairment who received an amyloid PET scan with 1 of 3 Aβ tracers (fluorine 18 [18F]-labeled florbetapir, 18F-labeled florbetaben, or 18F-labeled flutemetamol) between February 16, 2016, and January 10, 2018. A sample of older adults with mild cognitive impairment (MCI) or dementia was selected.

Exposures

Air pollution was estimated at the patient residence using predicted fine particulate matter (PM2.5) and ground-level ozone (O3) concentrations from the Environmental Protection Agency Downscaler model. Air quality was estimated at 2002 to 2003 (early, or approximately 14 [range, 13-15] years before amyloid PET scan) and 2015 to 2016 (late, or approximately 1 [range, 0-2] years before amyloid PET scan).

Main Outcomes and Measures

Primary outcome measure was the association between air pollution and the likelihood of amyloid PET scan positivity, which was measured as odds ratios (ORs) and marginal effects, adjusting for demographic, lifestyle, and socioeconomic factors and medical comorbidities, including respiratory, cardiovascular, cerebrovascular, psychiatric, and neurological conditions.

Results

The data set included 18 178 patients, of which 10 991 (60.5%) had MCI and 7187 (39.5%) had dementia (mean [SD] age, 75.8 [6.3] years; 9333 women [51.3%]). Living in areas with higher estimated biennial PM2.5 concentrations in 2002 to 2003 was associated with a higher likelihood of amyloid PET scan positivity (adjusted OR, 1.10; 95% CI, 1.05-1.15; z score = 3.93; false discovery rate [FDR]-corrected P < .001; per 4-μg/m3 increments). Results were similar for 2015 to 2016 data (OR, 1.15; 95% CI, 1.05-1.26, z score = 3.14; FDR-corrected P = .003). An average marginal effect (AME) of +0.5% (SE = 0.1%; z score, 3.93; 95% CI, 0.3%-0.7%; FDR-corrected P < .001) probability of amyloid PET scan positivity for each 1-μg/m3 increase in PM2.5 was observed for 2002 to 2003, whereas an AME of +0.8% (SE = 0.2%; z score = 3.15; 95% CI, 0.3%-1.2%; FDR-corrected P = .002) probability was observed for 2015 to 2016. Post hoc analyses showed no effect modification by sex (2002-2003: interaction term β = 1.01 [95% CI, 0.99-1.04; z score = 1.13; FDR-corrected P = .56]; 2015-2016: β = 1.02 [95% CI, 0.98-1.07; z score = 0.91; FDR-corrected P = .56]) or clinical stage (2002-2003: interaction term β = 1.01 [95% CI, 0.99-1.03; z score = 0.77; FDR-corrected P = .58]; 2015-2016: β = 1.03; 95% CI, 0.99-1.08; z score = 1.46; FDR-corrected P = .47]). Exposure to higher O3 concentrations was not associated with amyloid PET scan positivity in both time windows.

Conclusions and Relevance

This study found that higher PM2.5 concentrations appeared to be associated with brain Aβ plaques. These findings suggest the need to consider airborne toxic pollutants associated with Aβ pathology in public health policy decisions and to inform individual lifetime risk of developing AD and dementia.

Clinical Application of Computational Methods in Precision Oncology: A Review

Importance

There is an enormous and growing amount of data available from individual cancer cases, which makes the work of clinical oncologists more demanding. This data challenge has attracted engineers to create software that aims to improve cancer diagnosis or treatment. However, the move to use computers in the oncology clinic for diagnosis or treatment has led to instances of premature or inappropriate use of computational predictive systems.

Objective

To evaluate best practices for developing and assessing the clinical utility of predictive computational methods in oncology.

Evidence Review

The National Cancer Policy Forum and the Board on Mathematical Sciences and Analytics at the National Academies of Sciences, Engineering, and Medicine hosted a workshop to examine the use of multidimensional data derived from patients with cancer and the computational methods used to analyze these data. The workshop convened diverse stakeholders and experts, including computer scientists, oncology clinicians, statisticians, patient advocates, industry leaders, ethicists, leaders of health systems (academic and community based), private and public health insurance carriers, federal agencies, and regulatory authorities. Key characteristics for successful computational oncology were considered in 3 thematic areas: (1) data quality, completeness, sharing, and privacy; (2) computational methods for analysis, interpretation, and use of oncology data; and (3) clinical infrastructure and expertise for best use of computational precision oncology.

Findings

Quality control was found to be essential across all stages, from data collection to data processing, management, and use. Collecting a standardized parsimonious data set at every cancer diagnosis and restaging could enhance reliability and completeness of clinical data for precision oncology. Data completeness refers to key data elements such as information about cancer diagnosis, treatment, and outcomes, while data quality depends on whether appropriate variables have been measured in valid and reliable ways. Collecting data from diverse populations can reduce the risk of creating invalid and biased algorithms. Computational systems that aid clinicians should be classified as software as a medical device and thus regulated according to the potential risk posed. To facilitate appropriate use of computational methods that interpret high-dimensional data in oncology, treating physicians need access to multidisciplinary teams with broad expertise and deep training among a subset of clinical oncology fellows in clinical informatics.

Conclusions and Relevance

Workshop discussions suggested best practices in demonstrating the clinical utility of predictive computational methods for diagnosing or treating cancer.

Coronary Computed Tomography Angiography Compared With Single Photon Emission Computed Tomography Myocardial Perfusion Imaging as a Guide to Optimal Medical Therapy in Patients Presenting With Stable Angina: The RESCUE Trial

Background

The RESCUE (Randomized Evaluation of Patients with Stable Angina Comparing Utilization of Noninvasive Examinations) trial was a randomized, controlled, multicenter, comparative efficacy outcomes trial designed to assess whether initial testing with coronary computed tomographic angiography (CCTA) is noninferior to single photon emission computed tomography (SPECT) myocardial perfusion imaging in directing patients with stable angina to optimal medical therapy alone or optimal medical therapy with revascularization.

Methods and Results

The end point was first major adverse cardiovascular event (MACE) (cardiac death or myocardial infarction), or revascularization. Noninferiority margin for CCTA was set a priori as a hazard ratio (HR) of 1.3 (95% CI=0, 1.605). One thousand fifty participants from 44 sites were randomized to CCTA (n=518) or SPECT (n=532). Mean follow‐up time was 16.2 (SD 7.9) months. There were no cardiac‐related deaths. In patients with a negative CCTA there was 1 acute myocardial infarction; in patients with a negative SPECT examination there were 2 acute myocardial infarctions; and for positive CCTA and SPECT, 1 acute myocardial infarction each. Participants in the CCTA arm had a similar rate of MACE or revascularization compared with those in the SPECT myocardial perfusion imaging arm, (HR, 1.03; 95% CI=0.61‐1.75) (P=0.19). CCTA segment involvement by a stenosis of ≥50% diameter was a better predictor of MACE and revascularization at 1 year (P=0.02) than the percent reversible defect size by SPECT myocardial perfusion imaging. Four (1.2%) patients with negative CCTA compared with 14 (3.2%) with negative SPECT had MACE or revascularization (P=0.03).

Conclusions

There was no difference in outcomes of patients who had stable angina and who underwent CCTA in comparison to SPECT as the first imaging test directing them to optimal medical therapy alone or with revascularization. CCTA was a better predictor of MACE and revascularization.

Registration Information

URL: https://www.clinicaltrials.gov/. Identifier: NCT01262625.

Comparing the clinical impact of pancreatic cyst surveillance programs: A trial of the ECOG-ACRIN cancer research group (EA2185)

BACKGROUND

The optimal surveillance strategy for pancreatic cysts, which occur in up to 20% of the adult population, is ill defined. The risk of malignant degeneration of these cysts is low, however the morbidity and mortality associated with pancreatic cancer are high. Two clinical surveillance guidelines are in regular use. Both the Fukuoka and American Gastroenterological Association (AGA) guidelines rely on radiographic and endoscopic imaging. They differ primarily in their recommended frequencies of interval surveillance imaging. While evidence driven clinical guidelines should promote higher quality care, competing guidelines on the same topic may provide discordant recommendations and potential reduction in the quality and/or value of care.

OBJECTIVES

The primary objective is to compare the clinical effectiveness of the two surveillance guidelines to identify patients most likely to benefit from pancreatic resection. Secondary objectives include comparison of resource utilization, patient reported outcomes, incidental findings are other clinical outcomes.

METHODS

4606 asymptomatic patients with newly identified pancreatic cysts ≥1 cm in diameter will be randomized 1:1 to high intensity (Fukuoka) or low intensity (AGA) surveillance. All participants will be followed prospectively for 5 years.

CONCLUSION

Differing guidelines confuse providers, patients and policymakers. This large, prospective, randomized trial will compare the clinical effectiveness and resource allocation requirements of two guidelines addressing a common clinical entity. CLINICALTRIALS.

GOV IDENTIFIER

NCT04239573.

ECOG-ACRIN tomosynthesis mammographic imaging screening trial (EA1151)

TPS1597

Background: This randomized trial is intended to determine whether tomosynthesis (TM) should replace the current standard for breast cancer (BC) screening, digital mammography (DM). It is hypothesized that the population of women assigned TM screening for 3-5 rounds will have fewer advanced cancers than the population assigned to DM screening. Methods: 164,946 women, ages 45 to 74 years who present for screening mammography and consent to participate will be enrolled across 150 sites in the US, Canada and abroad. Women will be randomized to TM or DM. The frequency and number of screening examinations over a five year period will vary based on menopausal status and whether they have specific risk factors, including - hormone use, family history of BC, deleterious genes, prior benign breast biopsy with diagnosis of LCIS or atypia any kind, or dense breasts. Blood and buccal cells will be collected from as many enrolled women as are willing to provide the samples. All breast biopsies during the trial will undergo gene expression analysis for the PAM50 and other progression pathways (PAM50-plus). All subjects enrolled will be followed long term for at least eight years. The primary endpoint is the proportion of participants who have an advanced breast cancer diagnosed at any time within 4.5 years of randomization in to the trial. Secondary endpoints include measures of diagnostic and predictive performance; rates of recall, biopsy, and interval cancers, prevalence of breast cancer subtypes, and tumor subtype based on PAM50-plus analysis. As of January 17th 2020, there are 104 sites open and 21,452 women enrolled in the trial. The DSMC last reviewed the trial in June 2019 and suggested that the trial continue as planned. Clinical trial information: NCT03233191.

A phase II/III study of perioperative nivolumab and ipilimumab in patients (pts) with locoregional esophageal (E) and gastroesophageal junction (GEJ) adenocarcinoma: A trial of the ECOG-ACRIN Cancer Research Group (EA2174)

TPS4651

Background: E/GEJ adenocarcinoma has a high mortality rate despite curative intent treatment. A pathologic complete response (pCR) is associated with better overall survival (OS) but occurs in less than 30% of pts. Immunotherapy is effective in the metastatic setting. Here we aim to evaluate the contribution of immunotherapy in the neoadjuvant and adjuvant settings in pts with locoregional E/GEJ cancer. Methods: This is a multi-center, randomized phase II/III trial. Surgical candidates with locoregional E/GEJ adenocarcinoma receive carboplatin AUC 2 IV and paclitaxel 50 mg/m2 IV, both weekly x 5 during concurrent radiation (50.4 Gy) either with or without nivolumab 240 mg IV during weeks 1 and 3, followed by surgery. Pts with no post-operative disease receive nivolumab 240 mg IV every 2 weeks for 12 cycles either with or without ipilimumab 1 mg/kg IV every 6 weeks for 4 cycles. Eligibility criteria include pts with T1-N1-3M0 or T2-3N0-2M0 disease whom are candidates for surgery, no prior chemotherapy or radiation for this disease, no prior immunotherapy, no significant autoimmune disease. Pts must be disease free for adjuvant treatment. Primary neoadjuvant endpoint is pCR rate; primary adjuvant endpoint is disease free survival (DFS). Secondary endpoints include toxicity, DFS and OS. Pre- and mid-treatment diffusion weighted imaging MRI will be conducted during the neoadjuvant portion of the study. A neoadjuvant safety run in of 30 pts is underway. Overall, 278 pts will be needed to detect an absolute improvement of 15% in pCR rate in pts receiving and not receiving neoadjuvant nivolumab and 236 pts will be needed to detect a HR of 0.65 in favor of adjuvant ipilimumab/nivolumab over nivolumab (90% power, one sided alpha of 0.10). Accrual is expected over 34 months at a rate of 8 patients per month. If favorable at interim analysis. Clinical trial information: NCT03604991 .

Comparison of Abbreviated Breast MRI vs Digital Breast Tomosynthesis for Breast Cancer Detection Among Women With Dense Breasts Undergoing Screening

IMPORTANCE

Improved screening methods for women with dense breasts are needed because of their increased risk of breast cancer and of failed early diagnosis by screening mammography.

OBJECTIVE

To compare the screening performance of abbreviated breast magnetic resonance imaging (MRI) and digital breast tomosynthesis (DBT) in women with dense breasts.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional study with longitudinal follow-up at 48 academic, community hospital, and private practice sites in the United States and Germany, conducted between December 2016 and November 2017 among average-risk women aged 40 to 75 years with heterogeneously dense or extremely dense breasts undergoing routine screening. Follow-up ascertainment of cancer diagnoses was complete through September 12, 2019.

EXPOSURES

All women underwent screening by both DBT and abbreviated breast MRI, performed in randomized order and read independently to avoid interpretation bias.

MAIN OUTCOMES AND MEASURES

The primary end point was the invasive cancer detection rate. Secondary outcomes included sensitivity, specificity, additional imaging recommendation rate, and positive predictive value (PPV) of biopsy, using invasive cancer and ductal carcinoma in situ (DCIS) to define a positive reference standard. All outcomes are reported at the participant level. Pathology of core or surgical biopsy was the reference standard for cancer detection rate and PPV; interval cancers reported until the next annual screen were included in the reference standard for sensitivity and specificity.

RESULTS

Among 1516 enrolled women, 1444 (median age, 54 [range, 40-75] years) completed both examinations and were included in the analysis. The reference standard was positive for invasive cancer with or without DCIS in 17 women and for DCIS alone in another 6. No interval cancers were observed during follow-up. Abbreviated breast MRI detected all 17 women with invasive cancer and 5 of 6 women with DCIS. Digital breast tomosynthesis detected 7 of 17 women with invasive cancer and 2 of 6 women with DCIS. The invasive cancer detection rate was 11.8 (95% CI, 7.4-18.8) per 1000 women for abbreviated breast MRI vs 4.8 (95% CI, 2.4-10.0) per 1000 women for DBT, a difference of 7 (95% CI, 2.2-11.6) per 1000 women (exact McNemar P = .002). For detection of invasive cancer and DCIS, sensitivity was 95.7% (95% CI, 79.0%-99.2%) with abbreviated breast MRI vs 39.1% (95% CI, 22.2%-59.2%) with DBT (P = .001) and specificity was 86.7% (95% CI, 84.8%-88.4%) vs 97.4% (95% CI, 96.5%-98.1%), respectively (P < .001). The additional imaging recommendation rate was 7.5% (95% CI, 6.2%-9.0%) with abbreviated breast MRI vs 10.1% (95% CI, 8.7%-11.8%) with DBT (P = .02) and the PPV was 19.6% (95% CI, 13.2%-28.2%) vs 31.0% (95% CI, 17.0%-49.7%), respectively (P = .15).

CONCLUSIONS AND RELEVANCE

Among women with dense breasts undergoing screening, abbreviated breast MRI, compared with DBT, was associated with a significantly higher rate of invasive breast cancer detection. Further research is needed to better understand the relationship between screening methods and clinical outcome.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02933489.

Association of Magnetic Resonance Imaging and a 12-Gene Expression Assay With Breast Ductal Carcinoma In Situ Treatment

Importance

Advanced diagnostics, such as magnetic resonance imaging (MRI) and gene expression profiles, are potentially useful to guide targeted treatment in patients with ductal carcinoma in situ (DCIS).

Objectives

To examine the proportion of patients who converted to mastectomy after MRI and the reasons for those conversions and to measure patient adherence to radiotherapy guided by the 12-gene DCIS score.

Design, Setting, and Participants

Analysis of a prospective, cohort, nonrandomized clinical trial that enrolled women with DCIS on core biopsy who were candidates for wide local excision (WLE) from 75 institutions from March 25, 2015, to April 27, 2016, through the Eastern Cooperative Oncology Group-American College of Radiology Imaging Network trial E4112.

Interventions

Participants underwent breast MRI before surgery, and subsequent management incorporated MRI findings for choice of surgery. The DCIS score was used to guide radiotherapy recommendations among women with DCIS who had WLE as the final procedure and had tumor-free excision margins of 2 mm or greater.

Main Outcomes and Measures

The primary end point was to estimate the conversion rate to mastectomy and the reason for conversion.

Results

Of 339 evaluable women (mean [SD] age, 59.1 [10.1] years; 262 [77.3%] of European descent) eligible for WLE before MRI, 65 (19.2%; 95% CI, 15.3%-23.7%) converted to mastectomy. Of these 65 patients, conversion was based on MRI findings in 25 (38.5%), patient preference in 25 (38.5%), positive margins after attempted WLE in 10 (15.4%), positive genetic test results in 3 (4.6%), and contraindication to radiotherapy in 2 (3.1%). Among the 285 who had WLE performed after MRI as the first surgical procedure, 274 (96.1%) achieved successful breast conservation. Of 171 women eligible for radiotherapy guided by DCIS score (clear margins, absence of invasive disease, and score obtained), the score was low (<39) in 82 (48.0%; 95% CI, 40.6%-55.4%) and intermediate-high (≥39) in 89 (52.0%; 95% CI, 44.6%-59.4%). Of these 171 patients, 159 (93.0%) were adherent with recommendations.

Conclusions and Relevance

Among women with DCIS who were WLE candidates based on conventional imaging, multiple factors were associated with conversion to mastectomy. This study may provide useful preliminary information required for designing a planned randomized clinical trial to determine the effect of MRI and DCIS score on surgical management, radiotherapy, overall resource use, and clinical outcomes, with the ultimate goal of achieving greater therapeutic precision.

Trial Registration

ClinicalTrials.gov identifier: NCT02352883.

Combining biomarker trajectories to improve diagnostic accuracy in prospective cohort studies with verification bias

In this paper, we develop methods to combine multiple biomarker trajectories into a composite diagnostic marker using functional data analysis (FDA) to achieve better diagnostic accuracy in monitoring disease recurrence in the setting of a prospective cohort study. In such studies, the disease status is usually verified only for patients with a positive test result in any biomarker and is missing in patients with negative test results in all biomarkers. Thus, the test result will affect disease verification, which leads to verification bias if the analysis is restricted only to the verified cases. We treat verification bias as a missing data problem. Under both missing at random (MAR) and missing not at random (MNAR) assumptions, we derive the optimal classification rules using the Neyman-Pearson lemma based on the composite diagnostic marker. We estimate thresholds adjusted for verification bias to dichotomize patients as test positive or test negative, and we evaluate the diagnostic accuracy using the verification bias corrected area under the ROC curves (AUCs). We evaluate the performance and robustness of the FDA combination approach and assess the consistency of the approach through simulation studies. In addition, we perform a sensitivity analysis of the dependency between the verification process and disease status for the approach under the MNAR assumption. We apply the proposed method on data from the Religious Orders Study and from a non-small cell lung cancer trial.

Association of Amyloid Positron Emission Tomography With Subsequent Change in Clinical Management Among Medicare Beneficiaries With Mild Cognitive Impairment or Dementia

IMPORTANCE

Amyloid positron emission tomography (PET) detects amyloid plaques in the brain, a core neuropathological feature of Alzheimer disease.

OBJECTIVE

To determine if amyloid PET is associated with subsequent changes in the management of patients with mild cognitive impairment (MCI) or dementia of uncertain etiology.

DESIGN, SETTING, AND PARTICIPANTS

The Imaging Dementia-Evidence for Amyloid Scanning (IDEAS) study was a single-group, multisite longitudinal study that assessed the association between amyloid PET and subsequent changes in clinical management for Medicare beneficiaries with MCI or dementia. Participants were required to meet published appropriate use criteria stating that etiology of cognitive impairment was unknown, Alzheimer disease was a diagnostic consideration, and knowledge of PET results was expected to change diagnosis and management. A total of 946 dementia specialists at 595 US sites enrolled 16 008 patients between February 2016 and September 2017. Patients were followed up through January 2018. Dementia specialists documented their diagnosis and management plan before PET and again 90 (±30) days after PET.

EXPOSURES

Participants underwent amyloid PET at 343 imaging centers.

MAIN OUTCOMES AND MEASURES

The primary end point was change in management between the pre- and post-PET visits, as assessed by a composite outcome that included Alzheimer disease drug therapy, other drug therapy, and counseling about safety and future planning. The study was powered to detect a 30% or greater change in the MCI and dementia groups. One of 2 secondary end points is reported: the proportion of changes in diagnosis (from Alzheimer disease to non-Alzheimer disease and vice versa) between pre- and post-PET visits.

RESULTS

Among 16 008 registered participants, 11 409 (71.3%) completed study procedures and were included in the analysis (median age, 75 years [interquartile range, 71-80]; 50.9% women; 60.5% with MCI). Amyloid PET results were positive in 3817 patients with MCI (55.3%) and 3154 patients with dementia (70.1%). The composite end point changed in 4159 of 6905 patients with MCI (60.2% [95% CI, 59.1%-61.4%]) and 2859 of 4504 patients with dementia (63.5% [95% CI, 62.1%-64.9%]), significantly exceeding the 30% threshold in each group (P < .001, 1-sided). The etiologic diagnosis changed from Alzheimer disease to non-Alzheimer disease in 2860 of 11 409 patients (25.1% [95% CI, 24.3%-25.9%]) and from non-Alzheimer disease to Alzheimer disease in 1201 of 11 409 (10.5% [95% CI, 10.0%-11.1%]).

CONCLUSIONS AND RELEVANCE

Among Medicare beneficiaries with MCI or dementia of uncertain etiology evaluated by dementia specialists, the use of amyloid PET was associated with changes in clinical management within 90 days. Further research is needed to determine whether amyloid PET is associated with improved clinical outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02420756.

Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies: The PRISMA-DTA Statement

Importance

Systematic reviews of diagnostic test accuracy synthesize data from primary diagnostic studies that have evaluated the accuracy of 1 or more index tests against a reference standard, provide estimates of test performance, allow comparisons of the accuracy of different tests, and facilitate the identification of sources of variability in test accuracy.

Objective

To develop the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) diagnostic test accuracy guideline as a stand-alone extension of the PRISMA statement. Modifications to the PRISMA statement reflect the specific requirements for reporting of systematic reviews and meta-analyses of diagnostic test accuracy studies and the abstracts for these reviews.

Design

Established standards from the Enhancing the Quality and Transparency of Health Research (EQUATOR) Network were followed for the development of the guideline. The original PRISMA statement was used as a framework on which to modify and add items. A group of 24 multidisciplinary experts used a systematic review of articles on existing reporting guidelines and methods, a 3-round Delphi process, a consensus meeting, pilot testing, and iterative refinement to develop the PRISMA diagnostic test accuracy guideline. The final version of the PRISMA diagnostic test accuracy guideline checklist was approved by the group.

Findings

The systematic review (produced 64 items) and the Delphi process (provided feedback on 7 proposed items; 1 item was later split into 2 items) identified 71 potentially relevant items for consideration. The Delphi process reduced these to 60 items that were discussed at the consensus meeting. Following the meeting, pilot testing and iterative feedback were used to generate the 27-item PRISMA diagnostic test accuracy checklist. To reflect specific or optimal contemporary systematic review methods for diagnostic test accuracy, 8 of the 27 original PRISMA items were left unchanged, 17 were modified, 2 were added, and 2 were omitted.

Conclusions and Relevance

The 27-item PRISMA diagnostic test accuracy checklist provides specific guidance for reporting of systematic reviews. The PRISMA diagnostic test accuracy guideline can facilitate the transparent reporting of reviews, and may assist in the evaluation of validity and applicability, enhance replicability of reviews, and make the results from systematic reviews of diagnostic test accuracy studies more useful.