Test Pattern Research Articles

Real-world data on ALK rearrangement test in Chinese advanced non-small cell lung cancer (RATICAL): a nationwide multicenter retrospective study.

Anaplastic lymphoma kinase (ALK) test in advanced non-small cell lung cancer (NSCLC) can help physicians provide target therapies for patients harboring ALK gene rearrangement. This study aimed to investigate the real-world test patterns and positive rates of ALK gene rearrangements in advanced NSCLC. In this real-world study (ChiCTR2000030266), patients with advanced NSCLC who underwent an ALK rearrangement test in 30 medical centers in China between October 1, 2018 and December 31, 2019 were retrospectively analyzed. Interpretation training was conducted before the study was initiated. Quality controls were performed at participating centers using immunohistochemistry (IHC)-VENTANA-D5F3. The positive ALK gene rearrangement rate and consistency rate were calculated. The associated clinicopathological characteristics of ALK gene rearrangement were investigated as well. The overall ALK gene rearrangement rate was 6.7% in 23,689 patients with advanced NSCLC and 8.2% in 17,436 patients with advanced lung adenocarcinoma. The quality control analysis of IHC-VENTANA-D5F3 revealed an intra-hospital consistency rate of 98.2% (879/895) and an inter-hospital consistency rate of 99.2% (646/651). IHC-VENTANA-D5F3 was used in 53.6%, real-time polymerase chain reaction (RT-PCR) in 25.4%, next-generation sequencing (NGS) in 18.3%, and fluorescence in-situ hybridization (FISH) in 15.9% in the adenocarcinoma subgroup. For specimens tested with multiple methods, the consistency rates confirmed by IHC-VENTANA-D5F3 were 98.0% (822/839) for FISH, 98.7% (1,222/1,238) for NGS, and 91.3% (146/160) for RT-PCR. The overall ALK gene rearrangement rates were higher in females, patients of ≤ 35 years old, never smokers, tumor cellularity of > 50, and metastatic specimens used for testing in the total NSCLC population and adenocarcinoma subgroup (all P < 0.05). This study highlights the real-world variability and challenges of ALK test in advanced NSCLC, demonstrating a predominant use of IHC-VENTANA-D5F3 with high consistency and distinct clinicopathological features in ALK-positive patients. These findings underscore the need for a consensus on optimal test practices and support the development of refined ALK test strategies to enhance diagnostic accuracy and therapeutic decision-making in NSCLC.

The Performance of the Current Algorithm of HIV Diagnosis.

We aimed to evaluate the performance of the current algorithm the HIV diagnosis that has been performed for four years. Results of HIV Ag/Ab tests, anti-HIV 1/2 confirmatory tests, HIV-1 RNA tests and the time for official results to be approved were evaluated. The relationship of HIV Ag/Ab tests, anti-HIV 1/2 confirmation tests and HIV-1 RNA PCR tests, their result times and suitability to the algorithm were examined at Izmir Dokuz Eylül University between May 2017 and June 2021. HIV Ag/Ab ELISA was reactive repetitively in 165/54628 (0.30%) serum samples. Anti-HIV 1/2 confirmation test was reactive in 54.42% (80/147) of samples. The most common pattern (18.2%) in the confirmation tests was the positivity of the antibodies against gp160 - gp41 envelope glycoproteins together. The mean reporting time of the confirmation test result was 3h 50 min after the ELISA test. The mean reporting time of the HIV-1 RNA PCR was 12.79 d (±10.22) after the ELISA test and 12.63 (± 10.12) day after the confirmation test. In ROC analysis, the estimated rate of the ELISA test for the confirmation test was highest when S/CO was >13.16 (sensitivity: 97.59 %, specificity: 97.59%). The confirmation test in the current algorithm enabled the rapid test results, early diagnosis of HIV and early antiretroviral therapy. To use the new algorithm effectively, decentralization of the validation tests would be appropriate.

Adverse childhood experiences of Korean mothers with young children: a latent class analysis

ABSTRACT Background: Adverse childhood experiences (ACEs) have negative impacts on women with children, including psychosocial and general health problems. However, there is limited research investigating ACEs identifying the characteristics of distinct subgroups according to the frequency of ACEs. Objective: Utilizing the national dataset of the Family with Children Life Experience 2017, this study aimed to classify patterns of ACEs based on the total number of types of ACEs and the types of predominant events, and to examine differences in general and psychological characteristics, as well as experiences of violence in adulthood among the classes identified. Method: A total of 460 Korean mothers raising infants or toddlers participated. Latent class analysis was performed to classify the patterns of ACEs, while t-tests and Chi-square tests were used to examine differences in general and psychological characteristics and experiences of violence between the ACEs subgroups. Results: The participants were classified into two subgroups: the ‘high-ACEs group’ and the ‘low-ACEs group’. The high-ACEs group exhibited higher rates of child abuse, workplace violence perpetration and victimization, as well as lower self-esteem, higher depression levels, and increased suicidal thoughts compared to those of the low-ACEs group. Conclusion: The findings highlight the significant role of ACEs on the formation of an individual’s psychological characteristics and their propensity to experience additional violence even into adulthood, as perpetrators and as victims. It is noteworthy how the influence of ACEs extends across generations through child abuse. These findings offer insights for developing interventions aimed at mitigating the negative effects of experiences of violence on mothers raising young children.

Detection of Typhoid Fever by Immuno Chromatographic Test (ICT) and Antibiotic Susceptibility Pattern of Salmonella Typhi in Chittagong Metropoliton City

Typhoid fever caused by the Salmonella typhi is a disease of global distribution and one of the major health problems in many developing countries. In this study, clinically suspected thirty five patients were enrolled from different diagnostic centers of Chittagong city. We evaluated the reliability of Immuno Chromatographic Test (ICT) compared to different diagnostic methods like blood/serum culture and serological/Widal test for early detection of the disease. A total of 18 (51.43%) and 20 (57.14%) samples were found positive in culture method and Widal test, respectively, whereas 31 (88.57%) were found positive in ICT. Moreover, 13 culture negative and 11 Widal test negative samples were found positive in ICT. As the ICT showed satisfactory results compared to the other methods used in this survey, it can be considered as a reliable method for the early detection of typhoid infection. The study revealed several antibiotic resistant patterns by standard disc diffusion method, 12 (66.66%) out of 18 culture positives were found multi-drug resistant. The Chittagong Univ. J. B. Sci.,Vol. 10(1 &amp;2):53-70, 2020

Summary and Roadmap of Breast Cancer Research in the Veterans Affairs.

Women are the largest growing population of Veterans within the U.S. Department of Veterans Affairs (VA) Health Care System. Among women Veterans, breast cancer is the most common malignancy (30% of all cancers), yet little is known about the unique needs of women Veterans with cancer and how to provide them with high quality care. The VA health care system has initiated multiple system-wide systemic efforts, including launching the Breast and Gynecologic Cancer System of Excellence (BGSOE) to address this knowledge gap. This report summarizes the outcomes of the inaugural 2023 VA Women's Cancer Research Conference, which assembled 37 multidisciplinary clinicians, scientists, the VA and civilian partners with a shared goal of advancing VA breast cancer research. Conference objectives were to build a collective vision for improving: (1) referral patterns for breast cancer treatment and patient-level outcomes and (2) molecular and genetic testing patterns across the breast cancer continuum among women Veterans. The meeting hosted 15 speakers at the Houston VA Medical Center. Future research priorities for women Veterans with cancer were identified from discussions and a post-conference survey. We then administered a 13-question post-conference survey to conference attendees. Respondents ranked the research priorities. The survey results show that the cross-cutting cancer research priorities designed to transform cancer care for women Veterans at the VA fit into 5 broad areas of study, including (1) care quality for treatment, (2) improving treatment, (3) care quality of molecular and genetic testing, (4) risk reduction through risk assessment and germline genetic testing, and (5) establishing strategic partnerships. Our data elucidate areas for further investigation to improve the delivery of cancer care.

A Multifaceted Assessment of Benign Prostatic Hyperplasia Practice and AUA Guideline Adherence.

Guidelines for benign prostatic hyperplasia (BPH) were initially formulated by the AUA to provide evidence-based reasoning for the management and care of men suffering from lower urinary tract symptoms due to BPH. Recommendations for a urinalysis and validated symptom questionnaire (AUA Symptom Score [AUASS]/International Prostate Symptom Score [IPSS]) have been long standing, making these data points a metric for examining guidelines adherence. A survey assessed providers' awareness of AUA BPH guidelines and practice patterns, and was sent to a randomly selected portion of the AUA membership. The AUA Quality (AQUA) Registry was queried to assess testing and practice patterns. Of 4884 invitations sent, 404 responses were received. Most survey respondents (91.8%) indicate they intend to get a urinalysis at initial evaluation. AQUA data found urinalysis was obtained in only 22.8% of patients. Symptom questionnaire use increased with increasing guideline familiarity, with 95.7% of those who are "extremely familiar" routinely using AUASS/IPSS compared to only 69.4% who are "somewhat familiar" (P < .005). Utilization increased by a factor of 2.7 (P < .005) for each increment in familiarity. The lowest use of AUASS/IPSS was in the group within 5 years of finishing training (P = .069). Discrepancies are noted between our practice survey and AQUA data. The AUASS/IPSS is less commonly used by providers with less guideline familiarity and in providers with the least clinical experience. The intent to obtain urinalysis is high; however, actual testing is unfortunately infrequent. These findings could point toward the need for increasing education of providers with regard to clinical guidelines.

Clinical characteristics and treatment patterns of patients with NTRK fusion-positive solid tumors: A multisite cohort study at US academic cancer centers.

Neurotrophic tyrosine receptor kinase (NTRK) gene fusions are rare oncogenic drivers prevalent in 0.3% of solid tumors. They are most common in salivary gland cancer (2.6%), thyroid cancer (1.6%), and soft-tissue sarcoma (1.5%). Currently, there are 2 US Food and Drug Administration-approved targeted therapies for NTRK gene fusions: larotrectinib, approved in 2018, and entrectinib, approved in 2019. To date, the real-world uptake of tyrosine receptor kinase inhibitor (TRKi) use for NTRK-positive solid tumors in academic cancer centers remains largely unknown. To describe the demographics, clinical and genomic characteristics, and testing and treatment patterns of patients with NTRK-positive solid tumors treated at US academic cancer centers. This was a retrospective chart review study conducted in academic cancer centers in the United States. All patients diagnosed with an NTRK fusion-positive (NTRK1, NTRK2, NTRK3) solid tumor (any stage) and who received cancer treatment at participating sites between January 1, 2012, and July 1, 2023, were included in this study. Patient demographics, clinical characteristics, genomic characteristics, NTRK testing data, and treatment patterns were collected from electronic medical records and analyzed using descriptive statistics as appropriate. In total, 6 centers contributed data for 55 patients with NTRK-positive tumors. The mean age was 49.3 (SD = 20.5) years, 51% patients were female, and the majority were White (78%). The median duration of time from cancer diagnosis to NTRK testing was 85 days (IQR = 44-978). At the time of NTRK testing, 64% of patients had stage IV disease, compared with 33% at cancer diagnosis. Prevalent cancer types in the overall cohort included head and neck (15%), thyroid (15%), brain (13%), lung (13%), and colorectal (11%). NTRK1 fusions were most common (45%), followed by NTRK3 (40%) and NTRK2 (15%). Across all lines of therapy, 51% of patients (n = 28) received a TRKi. Among TRKi-treated patients, 71% had stage IV disease at TRKi initiation. The median time from positive NTRK test to initiation of TRKi was 48 days (IQR = 9-207). TRKis were commonly given as first-line (30%) or second-line (48%) therapies. Median duration of therapy was 610 (IQR = 182-764) days for TRKi use and 207.5 (IQR = 42-539) days for all other first-line therapies. This study reports on contemporary real-world NTRK testing patterns and use of TRKis in solid tumors, including time between NTRK testing and initiation of TRKi therapy and duration of TRKi therapy.

Cost-effectiveness of large-panel next-generation sequencing in guiding first-line treatment decisions for patients with nonsquamous advanced non-small cell lung cancer.

Clinical practice guidelines recommend broad-panel genomic profiling to identify actionable genomic alterations for patients with advanced non-small cell lung cancer (aNSCLC). To assess the cost-effectiveness of large-panel next-generation sequencing (LP-NGS) compared with current empirical single-gene test (SGT) patterns to inform first-line treatment decisions for patients with aNSCLC from a US commercial payer perspective, accounting for the effect of testing turnaround time and time to treatment initiation. We developed a discrete-event simulation model to estimate the impact of LP-NGS vs SGT for patients with nonsquamous aNSCLC. Discrete events and timing included testing patterns, receipt of the initial test result, treatment initiation (targeted vs nontargeted therapies), switching, retesting, rebiopsies, clinical trial participation, progression on therapy, and death. LP-NGS and SGT cohorts each comprised 100,000 adults with aNSCLC simulated over a 5-year postdiagnosis period, assumed to have the same distribution of genomic alterations. The model predicted the proportion of patients receiving appropriate first-line therapy according to clinical practice guidelines. Economic outcomes included expected life-years gained, quality-adjusted life-years, and the total costs of care over 5 years. Sensitivity and scenario analyses explored the robustness of the base-case model results. In the base-case model, LP-NGS was likely to identify more alterations than SGT. Total 5-year costs per patient were $539,658 for LP-NGS and $544,550 for SGT (net difference, $4,892 lower costs per patient for LP-NGS), which is likely to be cost-effective 95.1% of the time. The most influential model parameters on the 5-year total costs of care were preprogression nondrug medical costs on nontargeted therapy, NGS turnaround time, and clinical trial participation. This study suggests that LP-NGS to guide first-line treatment decisions is clinically more appropriate (more likely to identify alterations and subsequently allocate patients to clinically appropriate therapy) and provides a dominant cost-effectiveness treatment strategy over 5 years for patients with newly diagnosed aNSCLC in the United States.

Synthesis of high conformalty Ti-Six-N films using (CH3)3CCl and SiH4; density functional theory simulation and film characterization

The step coverage of the atomic layer deposition (ALD) of Ti-N thin films was improved by the addition of (CH3)3CCl, and Si atoms were added during the Ti-N deposition to form a Ti-Six-N thin film. By ALD, four to eight cycles of the gas (CH3)3CCl/TiCl4/NH3 formed the Ti-N layer and, subsequently, one to two cycles of the gas SiH4/NH3 added Si atoms to formed the Ti-Six-N layer. The ALD process was repeated to form a thin film Ti-Six-N 150 Å (bilayer of (Ti-N) 80 Å + (Six-N) 70 Å) while adjusting the amounts of (CH3)3CCl and SiH4. The crystallinity of Ti-N was studied by X-ray diffraction (XRD), and its composition was studied using X-ray photoelectron spectroscopy and secondary ion mass spectrometry. The composition of the Ti-Six-N film was studied using electron energy loss spectroscopy and selected area electron diffraction, and its roughness was confirmed using atomic force microscopy. Transmission electron microscope was used to measures the thickness and composition of the Ti-Six-N film through location in a test pattern with an aspect ratio of 50:1. Step coverage improved to 99.9 % compared to conventional ALD Ti-N when using (CH3)3CCl. Additionally, (CH3)3CCl was more effective at lower temperatures (460 °C compared to 530 °C), and the effect of the (CH3)3CCl flow rate was saturated above 300 sccm.As the amount of (CH3)3CCl increased, the growth per cycle decreased from 0.29 Å/cycle to 0.15 Å/cycle. The addition of Si to the Ti-N film facilitated leakage gain by increasing the difference in the work function between the electrode and the capacitor, material but may have the side effect of pillar bending due to a decrease in crystallinity and hardness. We verified that the XRD (200)/(111) peak ratio decreased as the Si content increased. As a result, the optimal conditions for electrode Ti-Six-N were confirmed as follows: 300 sccm (CH3)3CCl Ti-N, SiH4 10 sccm Six-N combination.Furthermore, the Ti-Six-N layer can serve as the bottom electrode of a capacitor reduce the manufacturing process steps, and be a candidate for a solution for the electrode of the capacitor of a 5 nm node memory device.

X-Ray Multibeam Ptychography at up to 20 keV: Nano-Lithography Enhances X-Ray Nano-Imaging.

Hard X-rays are needed for non-destructive nano-imaging of solid matter. Synchrotron radiation facilities (SRF) provide the highest-quality images with single-digit nm resolution using advanced techniques such as X-ray ptychography. However, the resolution or field of view is ultimately constrained by the available coherent flux. To address this, the beam's incoherent fraction can be exploited using multiple parallel beams in an X-ray multibeam ptychography (MBP) approach. This expands the domain of X-ray ptychography to larger samples or more rapid measurements. Both qualities favor the study of complex composite or functional samples, such as catalysts, energy materials, or electronic devices. The challenge of performing ptychography at high energy and with many parallel beams must be overcome to extract the full advantages for extended samples while minimizing beam attenuation. Here, that challenge is overcome by creating a lens array using cutting-edge laser printing technology and applying it to perform scanning with MBP with up to 12 beams and at photon energies of 13 and 20 keV. This exceeds the measurement limits of conventional hard X-ray ptychography without compromising image quality for various samples: Siemens star test pattern, Ni/Al2O3 catalyst, microchip, and gold nano-crystalclusters.

HSD8 Homologous Recombination Repair Testing Patterns and Barriers in Metastatic Hormone-Sensitive and Metastatic Castration-Resistant Prostate Cancer across Europe: A Real-World Survey

HSD8 Homologous Recombination Repair Testing Patterns and Barriers in Metastatic Hormone-Sensitive and Metastatic Castration-Resistant Prostate Cancer across Europe: A Real-World Survey

TEE4EHR: Transformer event encoder for better representation learning in electronic health records

Irregular sampling of time series in electronic health records (EHRs) is one of the main challenges for developing machine learning models. Additionally, the pattern of missing values in certain clinical variables is not at random but depends on the decisions of clinicians and the state of the patient. Point process is a mathematical framework for analyzing event sequence data consistent with irregular sampling patterns. Our model, TEE4EHR, is a transformer event encoder (TEE) with point process loss that encodes the pattern of laboratory tests in EHRs. The utility of our TEE has been investigated in various benchmark event sequence datasets. Additionally, we conduct experiments on two real-world EHR databases to provide a more comprehensive evaluation of our model. Firstly, in a self-supervised learning approach, the TEE is jointly learned with an existing attention-based deep neural network, which gives superior performance in negative log-likelihood and future event prediction. Besides, we propose an algorithm for aggregating attention weights to reveal the events’ interactions. Secondly, we transfer and freeze the learned TEE to the downstream task for the outcome prediction, where it outperforms state-of-the-art models for handling irregularly sampled time series. Furthermore, our results demonstrate that our approach can improve representation learning in EHRs and be useful for clinical prediction tasks.

Mask 3D parameter optimization for improving imaging contrast of plasmonic lithography

Based on plasmonic lithography (PL) technology, and aiming at the special nano-optical effect of metal/dielectric multilayer composites and mask three-dimensional (M3D) effect, a method for optimizing mask parameters is proposed. As a common analytic formula, the optical transfer function method has been introduced to analyze the imaging process. In order to include the M3D effect, FDTD is used to quantitatively calculate the PL imaging results, and the aerial image (AI) intensity and the light intensity contrast of AI in the photoresist layer can be obtained. The simulation results suggest that the imaging resolution and light intensity contrast can be improved by optimizing the M3D parameters such as the sidewall angle, thickness, and material of the mask absorber. For the line space test pattern with critical dimension = 150 nm and pitch = 300 nm, the results indicate that the optimal sidewall angle is 40°, resulting in an increase in the light intensity contrast of 344%. The light intensity contrast with a mask thickness of 70 nm is improved by 11% when compared to a mask thickness of 60 nm. The use of Ta and opaque MoSi on glass as the mask absorber material improves the light intensity contrast to varying degrees compared to the Cr mask.

Effective stewardship strategies to enhance appropriateness of refer-out test requests in a Canadian tertiary centre laboratory

ObjectivesSpecialized testing conducted in reference laboratories is costly and often not optimally directed. Since 2016, our institution has worked to ensure the appropriateness of refer-out (RO) tests. We examine the impact of utilization initiatives on the patterns of requests and completed tests. Design and methodsIn 2016, 81 RO tests were selected for a more rigorous approval process. Physicians not pre-approved for testing received a prompt to consult with laboratory subject matter experts (SMEs) for further detail. After review, SMEs provided responses, approving or rejecting requests based on clinical relevance. Stewardship activities also included: repatriating tests locally, preferring Canadian over foreign institutions, unbundling tests, distributing educational memos, and introducing staged testing. We collected data on the number of requested (NoR) and number of completed (NoC) tests in 2015, before the implementation of the new vetting procedures, and for the post-implementation phase from 2016−2022. ResultsFor 62 targeted RO tests (including trace metals, vitamins, antibodies, and endocrine-related tests), there was a 33% reduction in NoR and a 51% reduction in NoC in 2022 compared to 2015. The total savings for the study period based on NoC was $807,736. The NoC rate for Neuronal antibody tests decreased to 48.6% in 2022, with cost savings of $17,123, and an additional $50,000 saved by changing the testing site. Insourcing apolipoprotein B and fecal calprotectin tests resulted in cost savings of $3,380 and $3,371, respectively, in 2022. ConclusionsAutomated messaging followed by a formal review of RO test requests is an effective utilization strategy that prevents redundant or clinically unjustified testing. This approach leads to significant economic savings and is expected to improve the efficiency of patient care.

Shifting Patterns of Sputum Culture Testing and Antibiotic Usage Among Patients With Pneumonia Before and After the COVID-19 Pandemic

Abstract The coronavirus disease 2019 (COVID-19) pandemic has greatly shifted the attitude of the public and health care workers toward health care practices. Furthermore, this pandemic led to reduced diagnostic testing of various diseases worldwide. This study investigated the impact of the COVID-19 pandemic on health care practices, mainly focusing on sputum culture testing for pneumonia and how these changes affected antibiotic selection and health outcomes. We conducted a retrospective observational study at the Tokyo Medical University Ibaraki Medical Center between January 2018 and December 2021. We compared clinical outcomes during the pre–COVID-19 and post–COVID-19 periods. These outcomes included microbiological test implementation (eg, sputum culture test), length of hospital stay, and in-hospital mortality. Of the 698 patients, 384 (55.0%) were from the pre–COVID-19 period, and 314 (45.0%) were from the post–COVID-19 period. The post–COVID-19 period was associated with a lower ordering rate of sputum cultures (odds ratio [OR], 0.68; 95% confidence interval [CI], 0.50–0.93). Furthermore, the post–COVID-19 period was associated with increased use of narrow-spectrum antibiotics (OR, 1.57; 95% CI, 1.12–2.21) and a higher rate of in-hospital death (OR, 1.78; 95% CI, 1.16–2.73). The COVID-19 pandemic has prompted changes in health care–seeking behaviors, affecting health care providers' diagnostic practices and potentially influencing patient outcomes. Our study outlines the importance of adapting health care strategies during pandemics. Further studies are required to understand the complex interplay among pandemic situations, diagnostic procedures, and patient prognosis.

Trends over time in liquid biopsy testing in patients with metastatic breast cancer (MBC) across the Mayo Clinic enterprise.

e13036 Background: In January 2023, the FDA approved elacestrant for ESR1-mutated, ER+/HER2- MBC based on a companion diagnostic cell free (cf)DNA test (Guardant Health). In this study, we analyze the trends of liquid biopsy utilization at Mayo Clinic (MC) over a 3 year period to understand the impact of this drug approval on testing patterns and identify emergent alterations in patients (pts) with MBC. Methods: We extracted clinically performed Guardant 360 and Guardant 360 CDx ordered at MC sites in Rochester (MN), Florida (FL), Arizona (AZ), and across 9 additional Mayo Clinic Health System (MCHS) sites. Pts with MBC were identified using the EMR and analyzing visit diagnosis codes and staging information. Shifts in testing patterns were analyzed over a 3 year period from January 1, 2021 - December 31, 2023. Data was collected on the number of tests, serial testing, frequency of pathogenic mutations, and emergent mutations in ESR1 and PIK3CA. Chi-square test was used to compare the categorical values. Results: Between 2021-2023, 2,741 pts with MBC were seen across all sites. A total of 408 cfDNA tests were performed in 370 unique patients with MBC. Most pts (90%) had 1 test performed. The proportion of pts with MBC tested was 85/1350 (6.3%) in 2021, 77/1495 (5.2%) in 2022, and 208/1558 (13.4%) in 2023. The increased proportion of pts tested in 2023 was statistically significant compared to prior years (p&lt;0.0001), while no difference was observed between 2021 and 2022 (p 0.19). Testing patterns varied by site, with FL ordering the highest number of tests, followed by MN and AZ. Of the 34 providers practicing during the entire period seeing more than 10 MBC pts, the number of providers ordering Guardant testing increased from 15/34 (2021) and 14/34 (2022) to 20/34 (2023), though not statistically significant (p 0.15). Of the 41% with EMR-documented staging available, testing was highest in the ER+/HER2- (81.3%) subtype, followed by TNBC (13.6%) and then HER2+ (5.2%). The most commonly identified mutations identified in the first testing were PIK3CA (41.1%), TP53 (40.5%), ESR1 (30.5%), and ATM (13.2%). D538G (8.0%), Y537N (4.4%), and Y537S (3.5%) were frequent emergent mutations seen in ESR1. Conclusions: We observed an increase in cfDNA testing at the start of 2023 which aligns with the FDA approval of elacestrant. We observed variation by site and individual providers that warrants further exploration to improve cfDNA testing in MBC pts at Mayo Clinic.

Genetic testing in cancer care: An assessment of current practice in Africa.

e13784 Background: Genetic testing provides forprecision oncologic intervention, improving outcomes and minimizing traditional cytotoxicity. It has caused a dramatic change in the oncology landscape but remains underutilized in Africa. Data on genetic alterations associated with cancer in people of African descent continue to be inadequate due to multi-layered factors such as availability and cost of testing, provider awareness and knowledge, and availability and cost of targeted therapy. With cancer projected to be the leading cause of mortality in Africa within the next two decades, identifying the current patterns of testing and reasons for low uptake is crucial for developing strategies to improve cancer care and outcomes in Africa. This study aimed to map the current utilization pattern of cancer genetic testing among oncologists in Africa. Methods: An online cross-sectional survey was administered to oncologists practicing in Africa. Responses were collected between September 2023 and January 2024 following IRB approval from the Lagos University Teaching Hospital Health Research and Ethics Committee. Surveys were administered in English and French. Results: 245 oncologists across 28 African countries participated in this study. The mean age of respondents was 41.6 (SD: 8.3), with 64.5% being male and Nigerians comprising the largest proportion (33.0%). The majority of respondents practice in public/government-owned facilities (44.1%), and 64.5% held consultant/attending positions. Survey findings showed that 69.8% of oncologists lacked confidence in understanding/interpreting genetic test results, 93.5% expressed the need for assistance in interpreting results, and 64.1% were unable to discuss findings confidently with patients. The most ordered test was BRCA1/2 (47.3%), while ABC and RB1 genes were the least commonly ordered (0.008% and 0.02%, respectively). The primary reason for ordering genetic tests (63.3%) was the potential to guide treatment planning. However, 54.7% reported not referring any patients for genetic testing in the past year. Barriers to testing included the high cost of tests (78%) and targeted therapies (60.4%). Furthermore, 67.8% of respondents lacked previous formal training in cancer genetics with nearly all respondents (97.6%) expressing interest in formal training and a preference for online courses (71.8%). Conclusions: This survey highlights the critical need to develop the capacity for understanding cancer genetic testing and targeted treatment options among oncologists in Africa. To optimize uptake, strategies must be developed to reduce testing costs through resource pooling and to reduce the high cost of targeted treatment. Oncologists should be encouraged to prioritize testing that guides actionable targets to promote the uptake of targeted treatment options in Africa.

PIK3CA testing and treatment patterns among patients with metastatic breast cancer in US community clinical practice.

e13059 Background: PIK3CA mutations are present in ~35-40% of HR+/HER2- breast cancer patients. Targeted treatments are approved and in development for patients with advanced disease, and clinical guidelines recommend biomarker testing. This retrospective cohort study characterized PIK3CA mutation testing and treatment patterns among HR+/HER2- metastatic breast cancer (mBC) patients in United States (US) community clinical practices. Methods: We used the nationwide Flatiron Health electronic health record-derived de-identified database to select patients diagnosed with HR+/HER2- mBC from January 2011 to May 2023. We described baseline characteristics of patients tested and not tested for PIK3CA mutation. We captured rates of PIK3CA mutation testing (anytime and ≤1 year) prior to starting first-line (1L), second-line (2L), and third-line (3L) treatment; test and sample types; secular trends over time; and test turnaround time (TAT). Treatment patterns for patients with a PIK3CA-mutated tumor were also described from 2019 onwards. Results: Among 14,246 HR+/HER2- mBC patients treated at community sites, 4,537 had a PIK3CA mutation test result during the study period. 25% of patients had more than one PIK3CA mutation test. Test rates increased from 2011 to 2023 for all patients starting 1L, 2L, or 3L during the study period (Table). In 2023, the percentage of patients tested anytime prior to 1L, 2L, and 3L start dates were 11% (37 of 324 patients), 52% (140 of 271 patients), and 65% (133 of 204 patients), respectively. Among tested patients, those who were tested between 1L and 2L increased from 32% in 2018 to 45% in 2023. Median time from mBC diagnosis date to first test was variable across years: 8, 10, and 3 months in 2018, 2020, and 2022, respectively. During the study period, most PIK3CA mutation tests were next-generation sequencing (NGS) (88%) and used tumor tissue (72%). Median TAT decreased from 12 days in 2018 to 7 days in 2023. Among patients with a PIK3CA-mutated tumor in 2019 and onwards who received treatment, 36% of patients received alpelisib-containing regimens. Conclusions: PIK3CA mutation testing in HR+/HER2- mBC patients has increased over time in community clinical practice, and timing has shifted to earlier lines of therapy among tested patients. However, overall testing and subsequent treatment with pathway-directed therapy are still low despite clinical guidelines, which may reflect potential gaps in access to PIK3CA mutation testing and the continued unmet need regarding available targeted agents within the current treatment landscape. [Table: see text]

Genetic ancestry-associated differences in genomic profiling and treatment patterns in pancreatic ductal adenocarcinoma (PDAC).

4138 Background: Prior epidemiological studies have explored race both as a population-level risk factor and as a factor influencing outcomes in PDAC. However, the impact of genetic ancestry on PDAC remains unclear. We assessed the genomic landscape, clinical care patterns, and outcomes across ancestries in a large and diverse PDAC cohort to determine the potential impact of genomics on ancestral disparities. Methods: A total of 24,948 patients diagnosed with PDAC who received tissue-biopsy based comprehensive genomic profiling (CGP; Foundation Medicine, Inc. (FMI)) as part of routine clinical care from Aug 2014-Sep 2023 were examined for genomic differences based on genetic ancestry which was determined using a SNP-based approach. The US-based de-identified Flatiron Health (FH)-FMI clinico-genomic database (CGDB) was used to assess testing and treatment patterns based on ancestry in 3,863 patients of European (EUR) and 414 patients of African (AFR) ancestry diagnosed with PDAC. Results: The genetic ancestry distribution in the overall cohort was 80.9% EUR, 10.0% AFR, 4.9% Admixed American, 3.5% East Asian, and 0.7% South Asian. AFR patients showed a slightly younger median age at biopsy than EUR (64 vs 67, p &lt; .001). KRAS, TP53, CDKN2A/ 2B and SMAD4 were the most commonly altered genes in the cohort, as expected. Compared to EUR, AFR patients were enriched in alterations in TP53 (85% vs 78%, p &lt; .001) and KRAS (95% vs 93%, p &lt; .001). While rare, alterations in GNAS, CHEK2, and BRAF were observed less frequently in AFR (1.7% vs 3.3%, 0.3% vs 1.7%, 0.9% vs 2.2%, respectively, all p &lt; .001). In the CGDB cohort, AFR patients were likely to have lower socioeconomic status (SES) compared to EUR patients (33% of AFR in the lowest SES quintile compared to 9% of EUR; p &lt; .001 across all quintiles). AFR patients were less likely to receive care at academic centers (AFR 14.8% vs EUR 22.2%, p &lt; .001) and less likely to receive an investigational drug during their cancer treatment course (5.9% vs 14.1%, p = .001). Rates of surgery (AFR 30.2% vs EUR 34.6%, p = .08), immunotherapy (3.2% vs 3.3%, p &gt; .99), and targeted therapy (4.1% vs 6.2%, p = .28) were not significantly different. While AFR patients comprised a significantly larger proportion of AFR+EUR CGP volume following the decision to implement Medicare coverage for NGS testing (10.6% after Mar 16, 2018 vs 6.6% prior, p &lt; .001), this remained below the expected based on share of the overall US population. Conclusions: To our knowledge, this is the largest study of genetic ancestry in PDAC to date. There were largely similar patterns of gene alterations across AFR and EUR ancestry groups suggesting non-genomic factors may underlie clinical outcomes disparities which have been reported in other studies. Notably, there were ancestry-based differences associated with SES and both CGP testing and clinical trial enrollment patterns, which may impact patient outcomes.

57‐2: Invited Paper: Reproducible Characterization of Automotive Full Area Local Dimming (FALD) LCDs

We research measurement conditions that allow omitting stray light blocking masks in camera‐based halo measurements of FALD LCDs. The stray light induced error is reduced by using high magnifications and stray light optimized hardware and test patterns. Our findings simplify halo measurements and enable simultaneous peak luminance and uniformity measurements.