Introduction Frontline therapy for pts with follicular lymphoma (FL) is not based on the molecular profile of the tumor. The PI3K pathway is central to FL biology, but the molecular profile of tumors most sensitive to PI3K inhibition (PI3Ki) is unknown. Copanlisib inhibits both PI3Kα and δ isoforms, and we hypothesized that most pts with treatment naïve FL will have PI3Ki-sensitive tumors and durable complete responses (CRs) may be achievable with short durations of targeted therapy. A gene expression profiling (GEP) predictor utilizes a combination of the expression of 45 selected informative genes and an additional 19 housekeeping genes to identify FL pts at high-risk for early progression within 24 months (Wright et al. ASH Annual Meeting2022). We also hypothesized that copanlisib would induce durable CRs in high-risk pts by the GEP assay. Here, we report a preliminary analysis of an ongoing “window of opportunity” study of copanlisib followed by response-adapted copanlisib and rituximab in treatment-naïve pts with FL (NCT03789240). Methods Pts with untreated grade 1-2, 3A FL, ≥stage 2 are eligible if systemic therapy is indicated: symptoms, progressive lymphadenopathy, or organ compromise. Prior radiation is permitted. Eligibility includes age ≥18 and adequate organ function unless due to lymphoma. HIV, CMV, Hep B or C, and autoimmune conditions are excluded. Pts first receive copanlisib 60mg on days 1, 8, and 15 of a 28-day “window of opportunity” to explore the activity of copanlisib. Following the window, pts receive 6 cycles of copanlisib 60mg on days 1, 8, and 15 of a 28-day cycle along with rituximab 375mg weekly x 4 then on day 1 of each cycle and response is assessed with FDG-PET and CT scans. Pts without response after C6 are taken off study and those with a partial response (PR) can continue for an additional 6 cycles and then stop therapy. Pts who achieve a CR after 6 cycles stop therapy. No maintenance is given. Supportive care includesPCP prophylaxis. The primary endpoint is the CR rate with secondary endpoints of safety, duration of CR, and PFS. Exploratory objectives include identification of a predictive signature of PI3Ki response and the response rate in high-risk pts identified by the GEP assay. Results Twenty-eight pts have enrolled. Median age was 56y (range, 24-80). Seventeen (61%) and 12 (43%) pts had high-risk FLIPI and FLIPI-2 scores ≥3, respectively; 6 (21%) pts had Grade 3A FL, and 17 (61%) pts met two or more GELF criteria. After copanlisib monotherapy in the window, 27 (96%) pts had tumor reductions by CT with a median change of -38% (-62% to +16%) (Figure 1). Among 22 pts who completed 6 cycles, 21 (96%) responded, including 9 (41%) pts with PR and 12 (55%) pts with CR. Of 9 pts with PR who received an additional 6 cycles of therapy, only 1 (11%) converted to a CR bringing the overall CR rate to 59% (13/22 pts). After a median follow-up of 25.8 months, the 2-year PFS was 43.2% (95% CI, 20.7-64.0%). The median duration of CR was 29.7 months (95% CI, 6.3 months - not estimable) with 8 (62%) CRs ongoing (Figure 2). Toxicity was evaluated in 28 pts across 220 cycles. Most common were rash (64%), mucositis (50%), and nausea/vomiting (50%), all G1-2 except 1 (4%) pt with G3 mucositis. The most common ≥G3 toxicities were neutropenia and infections in 5 (18%) pts each. ≥G3 neutropenia occurred in 10 (5%) cycles, responded to therapy interruption and/or growth factors, and did not require dose reduction. Two (8%) pts had copanlisib dose reduced, 1 (4%) each due to rash and mucositis. Therapy was prematurely discontinued in 5 pts: 3 due to COVID-19, 1 for hepatotoxicity that resolved, and 1 due to infusion reaction to rituximab. Nine of 24 (38%) pts were poor risk by the GEP assay. Complete responses were observed in 71%, 67%, and 57% of pts categorized as high-risk by FLIPI, FLIPI-2, and GEP assay, respectively. The CR rate was not affected by bulky disease (any LN >7cm; p=1.00), high-risk FLIPI (p=0.19), high-risk FLIPI-2 (p=0.67), poor-risk GEP (p=1.00), or metabolic tumor volume (p=0.33). Conclusion Nearly all pts with treatment naïve FL have PI3Ki-responsive tumors, and the combination of copanlisib with rituximab achieved a CR rate of 59% at the end of induction therapy. The median duration of CR is nearly 30 months, including ongoing remissions without maintenance. CRs were observed in pts deemed high-risk by the GEP assay and FLIPI score. The safety profile is excellent, with mostly G1-2 toxicities manageable with supportive care.
Refining Diagnostic Subtypes of Peripheral T-Cell Lymphoma Using a Multiparameter Approach
Peripheral T-cell lymphoma (PTCL) encompasses a diverse group of post-thymic lymphomas, with ~40% of cases not further classifiable and designated as PTCL-not otherwise specified (PTCL-NOS). Two molecular prognostic subtypes of PTCL-NOS, PTCL-TBX21 and PTCL-GATA3, were identified through gene expression profiling (GEP). A subset of PTCL-NOS with T-follicular helper (TFH) differentiation was subsequently categorized as nodal PTCL with TFH phenotype (PTCL-TFH), also known in current classifications as nodal PTCL-TFH, NOS, or TFH lymphoma, NOS. However, the boundary between PTCL-NOS and PTCL-TFH remains poorly defined. To refine these subtypes, 101 PTCL-NOS with centralized pathology review and extensive immunophenotyping by immunohistochemistry (IHC) using 22 antibodies, digital GEP (nCounter, NanoString Inc) (n= 70), and RNA sequencing (n= 73) were included in this study. IHC was used to identify PTCL-TFH cases (those with strong expression of more than two TFH markers); the remaining patients were classified as PTCL-GATA3 and PTCL-TBX21 using pre-defined GEP signatures. Cases were reclassified into PTCL-NOS (n= 63) and PTCL-TFH (n= 38), with PTCL-NOS subclassified into PTCL-GATA3 (n= 22; 34%) and PTCL-TBX21 (n= 41; 66%) and showing significant differences in OS (p<0.001). PTCL-GATA3 was characterized by medium to large transformed cells (average= 90%, 70-100%) and had minimal tumor microenvironment (TME) (TME-poor: 100%). In contrast, PTCL-TBX21 was more heterogeneous, associated with pleomorphic cells in a polymorphous background (TME-rich: 78%), including Lennert lymphoma-like cases (22%). mRNA and CIBERSORT analysis substantiated the findings and identified a subset enriched in cytotoxic features in the PTCL-TBX21 subtype. IHC indicated that PTCL-GATA3 cases were CD4+/CD8- (83%) or CD4-/CD8- (17%) and lacked expression of CD8 or cytotoxic markers compared to PTCL-TBX21 (p<0.01). PTCL-GATA3 showed significantly higher expression of LEF1 (average= 80%), Ki67 (80%), and MYC (25%) than PTCL-TBX21 (25%, 30%, <5%, respectively, p<0.01). mRNA and protein expression of these biomarkers showed a significant positive correlation (r=0.5, p<0.001), and expectedly higher mRNA expression of LEF1 and MYC was observed in the PTCL-GATA3 versus PTCL-TBX21 (p<0.05). Strong expression of CD30 (>50% of cells) was only seen in PTCL-GATA3 cases. EBER positivity, found only in rare background cells, was not significantly different (18% of PTCL-GATA3 vs. 12% of PTCL-TBX21). Within PTCL-TBX21, we identified cytotoxic and non-cytotoxic subsets with divergent morphological, phenotypic, and clinical findings. The cytotoxic PTCL-TBX21 exhibited an activated cytotoxic phenotype (23/25, 96%), denoted by TIA1 and granzyme-B and/or perforin expression. Extranodal involvement and single-cell apoptosis were observed in 17% and 45% of the cytotoxic cases, respectively, but absent in non-cytotoxic PTCL-TBX21 cases. A trend towards higher Ki67 expression (average= 40% vs. 20%, p= 0.08) was seen in the cytotoxic subgroup. In contrast, the non-cytotoxic PTCL-TBX21 was associated with a CD4+/CD8- phenotype and higher ICOS expression (average= 30%) and CCR4 (60%) compared to the cytotoxic PTCL-TBX21 (p= 0.001). PTCL-TFH cases showed a CD4+/CD8- phenotype (90%) and rarely a CD4-/CD8- phenotype (10%). While a subset of PTCL-TFH cases had AITL-like features such as numerous clear cells and/or prominent vasculature (31% of cases), which were not seen in the other subgroups, the remaining cases exhibited morphology that was indistinguishable from other PTLC-NOS cases including sheets of transformed cells or pleomorphic cells in a polymorphous background. Morphologically, PTCL-TFH cases, like PTCL-TBX21 were associated with a rich TME (TME-rich: 75%). CIBERSORT analysis showed enrichment of plasma cells (p<0.01) in PTCL-TFH, compared to PTCL-TBX21, and validated by morphology (30% of cases vs. 5%). Expression of one TFH marker was frequent in some PTCL-NOS cases (PTCL-GATA3= 41% of cases, PTCL-TBX21-non cytotoxic= 47%, PTCL-TBX21-cytotoxic= 5%). Conclusion: Our comprehensive evaluation underscores the importance of integrating morphology, immunophenotyping, and GEP in achieving an accurate diagnosis, potentially leading to more tailored treatment strategies for PTCL. Correlation with pending whole-exome sequencing studies will be provided at the time of presentation.
Abstract B134: The art of science: Painting a new image of genomic research in the indigenous communities of the Southwest
Abstract Introduction: The Patient Engagement-Cancer Genome Sequencing Research Center (PE-CGS; NCI U2C CA252973) based at the University of New Mexico Comprehensive Cancer Center (UNMCCC) with partners at Mayo Clinic Comprehensive Cancer Center, the Translational Genomics Research Institute, and the Black Hills for American Indian Health Research Center are developing culturally appropriate strategies and methods to address the underrepresentation of American Indians (AIs) in genomic research. Our efforts are directed towards the implementation of tailored cancer prevention, diagnosis, and treatment strategies that reduce cancer health disparities in Tribal communities. Methods: The PE-CGS Center has three units, each tasked with specific research components to engage AI participants in participatory, clinically-meaningful genomic research: 1) the Participant Engagement Unit; 2) the Genomics Characterization Unit; and 3) the Engagement Optimization Unit (EOU). The Center also has a Tribal Advisory Committee, composed of Tribal Governors, Presidents, and tribal health advocates and experts, who provide direction on all research matters. The PE-CGS EOU uses iterative rapid-cycle research techniques to optimize engagement and shares these strategies with other units for timely implementation. To date, the EOU has developed and implemented three key efforts. First, to aid in recruiting participants for the study, the EOU tailored a series (6) of participant-facing informational materials that include artwork from a local AI artist who combined her traditional and scientific knowledge to prepare complementary imagery. Second, the EOU is currently implementing a series of semi-structured discussions to document participant perceptions on criteria including engagement, communication, and education. Lastly, the EOU implemented a survey among UNMCCC providers on their return of results processes. Results: EOU discussions are ongoing and have provided important perspectives on participant satisfaction and areas for improvement. Participants have commended study staff on their efforts to make enrollment straightforward. Participants report discussing the study with family prior to enrolling, highlighting the importance of continuing to engage with the entire community on the goals of the study. The provider return of results survey is complete (n=42/62, response rate=68%); one key finding was that providers who return somatic test results rarely provide participants with a hard copy of the results or utilize complementary materials that might enhance their explanation of the test findings. Conclusion: The EOU serves an innovative function through its rapid-cycle methods to optimize participant engagement. Although participants are generally pleased with their study participation, there are numerous opportunities for improvement. The informational materials represent a novel contribution to the field of genomic research. Efforts will continue to implement optimized processes for effective engagement of AI communities in genomic research and cancer care delivery. Citation Format: Shoshana Adler Jaffe, Kendal Jacobson, Joseph Rodman, Cindy Blair, Debra MacKenzie, Mallery Quetawki, Tamar Ginossar, V. Shane Pankratz, Andrew Sussman, Ursa Brown-Glabermen, Jeffrey Trent, Cheryl Willman, Shiraz I. Mishra. The art of science: Painting a new image of genomic research in the indigenous communities of the Southwest [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B134.
Peri-procedural myocardial infarction/injury after percutaneous coronary intervention
Predictive Value of high-sensitivity cardiac troponin T in patients undergoing 99mTc pyrophosphate scintigraphy for suspected transthyretin amyloid cardiomyopathy
Abstract Background Transthyretin amyloid cardiomyopathy (ATTR-CM) is an increasingly recognized cause of heart failure (1,2). 99mTc- pyrophosphate cardiac scintigraphy (PYP) enables accurate, noninvasive diagnosis of ATTR-CM when coupled with appropriate clinical and laboratory evaluations to rule out light chain amyloidosis (3,4). High sensitivity cardiac troponin T (hs-cTnT) is routinely assessed for diagnostic purposes when ATTR-CM is suspected in clinical practice. Purpose To investigate the diagnostic performance of hs-cTnT in patients undergoing PYP for suspected ATTR-CM. Methods Observational study of patients undergoing PYP at a United States (US) cardiac amyloidosis referral center from 2013 to September 2022 and with at least one hs-cTnT value available within 1 year. 3-hour planar imaging followed by single photon-emission computed tomography with computed tomography was performed. Final diagnoses of ATTR-CM were validated using all clinical information. The lowest reportable clinical value for hs-cTnT in the US is <6 ng/L (limit of quantitation). Results A total of 1572 patients underwent PYP and had a hs-cTnT value available within the study period. Of these, ATTR-CM was diagnosed in 475 patients (30%). Median (IQR) hs-cTnT was 48 (31-67) ng/L in patients with ATTR-CM and 26 (13-48) ng/L in those without. The area under the curve of hs-cTnT for the diagnosis of ATTR-CM was 0.69 (0.67-0.72). Among patients with a very low hs-cTnT value, i.e. <6 ng/L (n=100, 6.4% of the overall cohort), 7 (7%) patients had a final ATTR-CM diagnosis while 93 (93%) did not. Therefore, a threshold of <6 ng/L demonstrated a negative predictive value (NPV) of 93% (IQR 88, 98) and a sensitivity of 99% (97, 100) for ruling out ATTR-CM. The highest NPV was achieved with a threshold of 12 ng/L; 269 (17%) patients had hs-cTnT below this value and, of those, only 16 (6%) had a final diagnosis of ATTR-CM. This resulted in a NPV of 94% (91, 97) and a sensitivity of 97% (95, 98) for ruling out ATTR-CM. When considering progressively increasing hs-cTnT values as potential thresholds to aid in the prediction of ATTR-CM (Figure), we observed a progressive increase in specificity (above 90% for hs-cTnT values > 95 ng/L), but the positive predictive value (PPV) remained low (below 50%). Conclusions Among patients undergoing PYP for suspected ATTR-CM at a US referral center, a very low hs-cTnT value was present in a minority of patients but demonstrated good performance in ruling out ATTR-CM. The highest NPV (94%) was achieved with a threshold of < 12 ng/L. Higher hs-cTnT values showed a good specificity, but PPV remained low. Therefore, while a very low hs-cTnT might be of help in identifying those at low risk of ATTR-CM, the ubiquitous presence of increased hs-cTnT in many of these patients suggests the need for a multiparametric diagnostic approach to make the diagnosis.hs-cTnT in patients undergoing PYP scan
Diagnostic performance of the 0/2 hours ESC algorithm with high-sensitivity cardiac troponin T in an unselected community United States cohort
Abstract Background There are no robust data addressing the United States (US) experience with the 0/2 hours (h) European Society of Cardiology (ESC) algorithm using high-sensitivity cardiac troponin T (hs-cTnT). Purpose To evaluate the diagnostic performance of the 0/2h ESC-recommended absolute deltas in a US population. Methods Observational US cohort study of ED patients undergoing 0 and 2 h hs-cTnT measurements. The 99th percentiles upper reference limits (URL) used were 10 ng/L for women and 15 ng/L for men. Diagnostic outcomes were the adjudicated diagnoses of acute myocardial infarction (MI, type 1 or 2). Results A total of 1084 patients met inclusion criteria, amongst which 49% were women. Chest discomfort was reported in 521 (48%) patients. Among patients with a baseline hs-cTnT≤99th URL (n=434), 4 MIs occurred. To rule-out MI, an absolute 0-2h delta change <4 ng/L resulted in a sensitivity of 100% (95% CI: 39.8, 100) and a negative predictive value (NPV) of 100% (95% CI: 99.1, 100). To rule-in MI, an absolute 0-2h delta ≥10 ng/L had a specificity of 99.8 % (95% CI: 98.7, 99.9) and positive predictive value (PPV) of 75% (95% CI: 19.4, 99.4). Among patients with a baseline hs-cTnT >99th URL (n=650), 110 MIs occurred. In these patients, both rule-out (sensitivity 65%, NPV 91%) and rule-in (specificity 7.2%, PPV 11%) were poor using the ESC-recommended absolute deltas. Among patients with modest hs-cTnT increases (99th URL to 100 ng/L) neither the ESC-recommended absolute nor the Fourth Universal Definition of MI (UDMI)-recommended relative deltas provided acceptable performance. Among patients with marked hs-cTnT increases at presentation (>100 ng/L), a relative delta change >20% as recommended by the UDMI resulted in a superior rule-in performance, with a specificity of 92.0% (95% CI 74.0, 99.0) and PPV of 84.6% (57.4, 95.7). Conclusions In our unselected US-cohort of patients undergoing hs-cTnT, the 0/2h ESC algorithm had a good diagnostic performance in patients without myocardial injury at presentation. Conversely, in patients with myocardial injury at baseline, the ESC-recommended absolute deltas performed poorly to determine who had MI. In patients with marked hs-cTnT increases >100 ng/L at presentation, the UDMI recommended 20% relative change showed good rule-in performance.
Does a high baseline high sensitivity cardiac troponin T allow for the early diagnosis of acute myocardial infarction?
Abstract Background Guidelines suggest that the diagnosis of acute myocardial infarction (MI) is likely when high concentrations of high-sensitivity cardiac troponin (hs-cTn) are present in the initial sample. These concentration thresholds are much higher than the 99th percentile and are said to provide a high positive predictive value (PPV) for acute MI1. Purpose Evaluate the PPV of recommended baseline hs-cTnT thresholds (>52 and >100 ng/L) for the diagnosis of acute MI from our multi-center United States (US) experience. Methods Retrospective, multicenter (n=22), observational biomarker study involving consecutive, adult patients presenting to the emergency department (ED) in whom at least 1 hs-cTnT measurement was obtained within 12 hours of presentation (CV DataMart Biomarker cohort). The primary endpoint was also evaluated in an adjudicated cohort of consecutive patients presenting to the ED with at least 1 hs-cTnT >99th percentile (ACTION cohort). These cases were adjudicated based on the Fourth Universal Definition of MI by trained physicians. The primary efficacy endpoint was the PPV of acute MI (type 1 or 2), type 1 MI and type 2 MI during index hospitalization using baseline hs-cTnT thresholds of >52 ng/L and >100 ng/L. Results The CV DataMart Biomarker cohort consisted of 143,709 patients, amongst whom 3,003 (2.1%) were diagnosed with acute MI using ICD codes. In the CV DataMart Biomarker cohort, baseline hs-cTnT concentrations of >52 ng/L and >100 ng/L resulted in PPVs of 12% (95% CI: 11, 12) and 17% (95% CI: 17, 19) for acute MI, respectively. In patients with chest pain and baseline hs-cTnT concentrations >52 ng/L, PPV for acute MI was 17% (95% CI: 15, 18), and in those with hs-cTnT concentrations >100 ng/L, PPV was 22% (95% CI: 19, 25). The adjudicated ACTION cohort consisted of 2,107 patients, amongst whom 155 (7.4%) were diagnosed with acute MI including 64 (41%) with type 1 MI and 91 (59%) with type 2 MI. In the ACTION cohort, baseline hs-cTnT concentrations of >52 ng/L and >100 ng/L resulted in PPVs of 46% (95% CI: 40, 53) and 62% (95% CI: 53, 70) for acute MI, respectively. In patients with chest pain and baseline hs-cTnT concentrations >52 ng/L, PPV was 67% (95% CI: 57, 76) for acute MI, 52% (95% CI: 41, 62) for type 1 MI and 15% (95% CI: 8.4, 24) for type 2 MI. In those with chest pain and baseline hs-cTnT concentrations >100 ng/L, PPV was 77% (95% CI: 65, 87) for acute MI, 64% (95% CI: 51, 75) for type 1 MI and 14% (95% CI 6.4, 24) for type 2 MI (Figure). Conclusion Using previously recommended high-risk hs-cTnT thresholds of 52 and 100 ng/L in US patients provides reasonable performance to rule-in acute MI when used in patients with chest pain. When used more broadly across all-comers, the diagnostic performance is poor.
Cardiac Injury After Acute Ischemic Stroke: Are Women at Increased Risk?
A-008 Comparison of Roche 5th Generation Troponin T Analytical Outlier Rates Between the e411 Analyzer Using a Biotin-sensitive Reagent and the e601 Analyzer Using Reformulated (Biotin-insensitive) Reagent
Abstract Background Analytical outliers (fliers) occur with most troponin methods and can adversely affect patient management. We compared the analytical outlier rates for the Roche 5th generation Troponin T STAT (cTnT) reformulated (biotin-insensitive) reagent using a Cobas e601 analyzer (Indianapolis, IN) to rates observed in a previous study using the biotin-sensitive reagent on a Cobas e411 analyzer. Methods Plasma separator tubes (PST) were collected from hospital patients with orders for clinical cTnT testing. PST samples were centrifuged for 3 min at 4000g and analyzed using the biotin-insensitive cTnT Gen 5 assay on a Roche Cobas e601 immunoassay system. If samples displayed measurable cTnT Gen 5 (≥6 ng/L), samples were stored at 2–8 °C within 2 h of initial measurement (N = 2555). Within 24 h of initial analysis, samples were warmed to room temperature, aliquoted, re-centrifuged at 4000g for 3 min, and cTNT was re-measured on the same analyzer. Outlier rates were compared to a previous study (N = 1997) using nearly identical study design but using biotin-sensitive Roche 5th Gen cTnT reagent on an e411 analyzer. We defined analytical outliers by three methods: Repeat value (after aliquoting and re-centrifugation) that differed from the initial value for all samples with measurable cTnT by a critical difference (CD): where CD = z × √2 × SDanalytical, with a z-value of 3.719 and using SD from best fit line of precision vs cTnT concentration. Precision experiments were performed using four plasma pools in 5 × 5 precision experiment on the e411 analyzer. Using the same CD but considering only initial cTnT values <100 ng/L, those are most likely to be clinically significant or lead to misinterpretation. Using CD for initial values <100 ng/L, and a fixed 10% difference between replicates for initial values ≥100 ng/L, accounting for our practice of reporting the cTnT “delta” in percent (rather than absolute) for values ≥100 ng/L. Comparisons of outlier rates between the biotin-sensitive and biotin-insensitive reagents were performed using Pearson’s chi-squared test. Results Using the CD the total number of outliers that were observed for the biotin-insensitive reagent on the e601 was 208/2555 (8.1%), compared to 68/1997 (3.4%) on the biotin-sensitive reagent measured on the e411 (P < 0.0001). Outliers were observed in 138 (6.4%) of samples with initial values < 100 ng/L using the biotin-insensitive reagent on the e601 compared to 45 (2.6%) of such samples on the e411 (P < 0.0001). Using the Z score method to define outliers for initial values <100 ng/L and a fixed 10% to define outliers for initial values ≥100 ng/L, the outlier rate was 151 (5.9%) for the biotin-insensitive reagent on the e601 compared to 53 (2.7%) on the e411 (P < 0.0001). Conclusions Analytical outliers occurred more frequently using the reformulated (biotin-insensitive) reagent on the Roche Cobas e601 analyzer, compared to outlier rates observed for biotin-sensitive reagent on the Cobas e411.
A-221 Evaluation of Apolipoprotein B Equivalent Low-density Lipoprotein Cholesterol Measurements
Abstract Background Low-density lipoprotein cholesterol (LDL-C) is the primary biomarker for assessing risk for atherosclerotic cardiovascular disease (ASCVD). However, multiple large studies have demonstrated greater accuracy using Apolipoprotein B (apoB). One obstacle to its widespread use is the lack of guideline endorsed apoB treatment targets. A recently published solution has proposed using population percentiles to calculate LDL-C using apoB values (PMID: 36366949). The LDL-C concentration correlated to an individual’s ApoB percentile may more appropriately reflect ASCVD risk compared to lipid panel LDL-C. Here we evaluated this approach using a cohort where LDL-C was measured with the gold-standard beta-quantification method (LDL-CBQ). Method Results from clinically ordered apoB, LDL-CBQ, and lipid panel were included (n = 18 852). Samples with triglycerides >1000 mg/dL or LpX were excluded. Total cholesterol, high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), and apoB were measured using Roche Cobas c501 analyzers. LDL-CBQ was performed using Beckman LE-80K ultracentrifuge and dextran sulfate-Mg/Cl precipitation. ApoB equivalent LDL-C (eqLDL-CapoB) was calculated according to linear regression of LDL-C percentiles against apoB percentiles described by the equation eqLDL-CapoB = 1.45(apoB)-25. Concordance was determined based on clinical thresholds for LDL-CBQ and eqLDL-CapoB. Results Median (IQR) apoB and LDL-CBQ was 98 (79−119) mg/dL and 120 (94−150) mg/dL, respectively. LDL-CBQ and eqLDL-CapoB were concordant in 60% of samples overall. Discordance between eqLDL-CapoB and LDL-CBQ shifted from primarily overestimating to underestimating as LDL-CBQ increased. Discordant eqLDL-CapoB was directly associated with TG and inversely associated with HDL-C. Conclusion The eqLDL-CapoB calculation is a useful tool to present apoB results in a more familiar context of LDL-C-equivalent units. The concordance findings largely confirm previously published results using eqLDL-CapoB. Furthermore, the pattern of HDL-C and TG suggests that a discordantly elevated eqLDL-CapoB is an indicator of a higher risk lipid profile. More investigation is needed to determine if eqLDL-CapoB is appropriate for widespread adoption.