Citations

Abstract Richter syndrome (RS), an aggressive lymphoma that develops in patients with chronic lymphocytic leukemia (CLL), is a striking example of histologic transformation. While recent therapeutic advances have transformed the treatment landscape of CLL and lymphoma, RS remains associated with dismal overall survival. Despite an advanced genomic and molecular characterization of CLL over the past decade, the current understanding of the genetic factors driving evolution of CLL to RS is limited. To decipher the genetics underlying this transformation, we have performed an integrative analysis of exome, genome and transcriptome data generated from matched RS and CLL samples from a discovery cohort of 53 patients with newly diagnosed RS of DLBCL histology. Through computational deconvolution of CLL and RS clones, we constructed phylogenetic relationships and traced evolution of CLL to RS, confirming both clonal related (87%) and unrelated cases (13%). In addition to identifying recognized RS-risk genetic lesions, we discovered novel RS-specific alterations, including 5 putative somatic driver genes (IRF2BP2, SRSF1, B2M, DNMT3A and EZH2), frequent copy number alterations beyond del(9p21)(CDKN2A/B), (including amp(7q21.2) (CDK6), amp(9p24) (PDL1/L2), and amp(1q23)(MCL1)), and recurrent whole genome duplication and chromothripsis. Integration of exome and genome sequencing data led to the identification of distinct molecular subtypes of RS with prognostic importance. To confirm these molecular subtypes, a validation cohort of 47 RS cases has been assembled with paired exome and transcriptome data. To further investigate the stepwise clonal evolution of CLL to RS, we performed single-cell RNA-sequencing on biopsy samples obtained at diagnosis from 5 individuals with clonally related transformation. Using a novel tool, CNVSingle, we inferred allele specific single-cell copy number alterations that enabled identification of the single-cell clusters representing distinct CLL and RS genetic subclones as well as intermediate, or transitional, evolutionary states. RS cells displayed gene expression enriched in pathways of MYC targets and cell cycle, in line with similar analysis on bulk transcriptomes. Finally, by ultra-low pass (ULP)-WGS sequencing of plasma samples from RS patients, we demonstrate detection of RS tumor DNA in plasma months prior to initial clinical diagnosis (n=3 of 6) or post-allogeneic stem cell transplant relapse (n=2 of 2). cfDNA is thus a promising tool for early detection of emerging RS and RS relapse as well as for non-invasive detection surrounding diagnosis. Altogether, our study defines RS-specific alterations and provides a molecular definition of RS, identifies distinct genetic subtypes of RS with prognostic significance, traces the evolutionary path to RS and suggests future strategies for improved detection. Citation Format: Erin M Parry, Ignaty Leshchiner, Romain Guieze, Connor Johnson, Eugen Tausch, Sameer A Parikh, Camilla K Lemvigh, Conor Messer, Filippo Utro, Chaya Levovitz, Kahn Rhrissorrakrai, Matthew S Davids, Julien Broseus, Shuqiang Li, Ziao Lin, Binyamin A Knisbacher, Christof Schneider, Laura Z Rassenti, Thomas J Kipps, Nitin Jain, William Wierda, Florence Cymbalista, Neil E Kay, Kenneth J Livak, Brian P Danysh, Chip Stewart, Donna Neuberg, Jennifer R Brown, Laxmi Paridi, Stephan Stilgenbauer, Gaddy Getz, Catherine Wu. Evolutionary history of transformation from chronic lymphocytic leukemia to Richter syndrome [abstract]. In: Proceedings of the Third AACR International Meeting: Advances in Malignant Lymphoma: Maximizing the Basic-Translational Interface for Clinical Application; 2022 Jun 23-26; Boston, MA. Philadelphia (PA): AACR; Blood Cancer Discov 2022;3(5_Suppl):Abstract nr A13.

AbstractObjectivesThe assessment of physical function is fundamental in the management of patients with idiopathic inflammatory myopathies (IIMs). We aimed to investigate the physical function of patients with IIMs compared with those with non-IIM autoimmune rheumatic diseases (AIRDs) utilizing Patient-Reported Outcome Measurement Information System (PROMIS) Physical Function (PF) data obtained in the COVAD study, an international self-reported e-survey assessing the safety of COVID-19 vaccines in AIRDs.MethodsDemographics, AIRD diagnosis, disease activity, and PROMIS PF short form-10a data were extracted from the COVAD database. PROMIS PF-10a scores were compared between disease categories and stratified by disease activity. Factors affecting PROMIS PF-10a scores other than disease activity were identified by multivariable regression analysis in patients with inactive disease.ResultsA total of 1057 IIM patients, 3635 non-IIM AIRD patients and 3981 healthy controls (HCs) responded to the COVAD e-survey from April to August 2021. Using a binomial regression model, the predicted mean of PROMIS PF-10a scores was significantly lower in IIM patients compared with non-IIM AIRD patients or HCs [36.3 (95% CI 35.5, 37.1) vs 41.3 (95% CI 40.2, 42.5) vs 46.2 (95% CI 45.8, 46.6), P < 0.001], irrespective of disease activity. The independent factors for lower PROMIS PF-10a scores in patients with inactive disease were older age, female, longer disease duration, and a diagnosis of inclusion body myositis or polymyositis.ConclusionPhysical function is significantly impaired in IIMs compared with non-IIM AIRDs or HCs, even in patients with inactive disease. Our study highlights a critical need for better strategies to minimize functional disability in patients with IIMs.

ObjectiveSome patients with rheumatic diseases might be at higher risk for coronavirus disease 2019 (COVID‐19) acute respiratory distress syndrome (ARDS). We aimed to develop a prediction model for COVID‐19 ARDS in this population and to create a simple risk score calculator for use in clinical settings.MethodsData were derived from the COVID‐19 Global Rheumatology Alliance Registry from March 24, 2020, to May 12, 2021. Seven machine learning classifiers were trained on ARDS outcomes using 83 variables obtained at COVID‐19 diagnosis. Predictive performance was assessed in a US test set and was validated in patients from four countries with independent registries using area under the curve (AUC), accuracy, sensitivity, and specificity. A simple risk score calculator was developed using a regression model incorporating the most influential predictors from the best performing classifier.ResultsThe study included 8633 patients from 74 countries, of whom 523 (6%) had ARDS. Gradient boosting had the highest mean AUC (0.78; 95% confidence interval [CI]: 0.67‐0.88) and was considered the top performing classifier. Ten predictors were identified as key risk factors and were included in a regression model. The regression model that predicted ARDS with 71% (95% CI: 61%‐83%) sensitivity in the test set, and with sensitivities ranging from 61% to 80% in countries with independent registries, was used to develop the risk score calculator.ConclusionWe were able to predict ARDS with good sensitivity using information readily available at COVID‐19 diagnosis. The proposed risk score calculator has the potential to guide risk stratification for treatments, such as monoclonal antibodies, that have potential to reduce COVID‐19 disease progression.

Obstructive sleep apnea (OSA), a disease associated with excessive sleepiness and increased cardiovascular risk, affects an estimated 1 billion people worldwide. The present study examined proteomic biomarkers indicative of presence, severity, and treatment response in OSA. Participants (n = 1391) of the Stanford Technology Analytics and Genomics in Sleep study had blood collected and completed an overnight polysomnography for scoring the apnea–hypopnea index (AHI). A highly multiplexed aptamer-based array (SomaScan) was used to quantify 5000 proteins in all plasma samples. Two separate intervention-based cohorts with sleep apnea (n = 41) provided samples pre- and post-continuous/positive airway pressure (CPAP/PAP). Multivariate analyses identified 84 proteins (47 positively, 37 negatively) associated with AHI after correction for multiple testing. Of the top 15 features from a machine learning classifier for AHI ≥ 15 vs. AHI < 15 (Area Under the Curve (AUC) = 0.74), 8 were significant markers of both AHI and OSA from multivariate analyses. Exploration of pre- and post-intervention analysis identified 5 of the 84 proteins to be significantly decreased following CPAP/PAP treatment, with pathways involving endothelial function, blood coagulation, and inflammatory response. The present study identified PAI-1, tPA, and sE-Selectin as key biomarkers and suggests that endothelial dysfunction and increased coagulopathy are important consequences of OSA, which may explain the association with cardiovascular disease and stroke.

6080 Background: Alterations in RET are targetable oncogenic drivers in TC. Pralsetinib is a highly potent, selective RET inhibitor, with demonstrated efficacy in pts with RET-altered TC. In a previous analysis of the Phase I/II ARROW trial (NCT03037385; data cutoff: 22 May 2020), overall response rates [ORR; measurable-disease population] with pralsetinib at 400 mg once daily (QD) were 60% (33/55) and 71% (15/21) in pts with RET-mutant medullary TC ( RET-mutant MTC) who had received prior multikinase inhibitors cabozantinib and/or vandetanib (C/V), and those who were treatment naïve, respectively, and 89% (8/9) in pts with previously treated RET fusion-positive TC ( RET-fp TC). Here we report an updated analysis of these cohorts in the intention-to-treat (ITT) population. Methods: Adult pts with RET-altered locally advanced/metastatic TC who had enrolled in ARROW and initiated pralsetinib at 400 mg QD, were included. Phase II primary endpoints: ORR (by blinded independent central review, per RECIST v1.1) and safety. Efficacy endpoints for this analysis were assessed in the ITT population. Safety was assessed in all pts with RET-altered TC who initiated pralsetinib at 400 mg QD. Enrolment cutoff: 23 August 2020 for the ITT population; data cutoff: 12 April 2021. Results: The ITT population comprised 145 pts with RET-mutant MTC (with or without prior systemic therapy, including C/V) and 22 pts with RET-fp TC, 21 of whom had received prior systemic therapy (including multikinase inhibitor[s] and/or radioactive iodine). In pts with RET-mutant MTC who had received prior C/V (n = 67), ORR was 51% (34/67; 95% CI 38–63; 2 complete responses [CR]; 32 partial responses [PR]), median duration of response (DoR) was 25.8 months (95% CI 18.0–not reached [NR]) and median progression-free survival (PFS) was 24.9 months (95% CI 19.7–31.2). In treatment-naïve pts with RET-mutant MTC, ORR was 72% (48/67; 95% CI 59–82; 4 CR; 44 PR), and median DoR and median PFS were not reached. In pts with previously treated RET-fp TC, ORR was 86% (18/21; 95% CI 64–97; 3 CR; 15 PR), median DoR was 17.5 months (95% CI 16.0–NR) and median PFS was 19.4 months (95% CI 13.0–NR). Median overall survival (OS) was not reached in any of the cohorts. The safety population comprised 172 pts with RET-altered TC treated at 400 mg QD. The most common treatment-related adverse events (TRAEs) were increased aspartate aminotransferase (n = 67; 39%), anemia (n = 60; 35%), hypertension (n = 57; 33%) and decreased white blood cell count (n = 52; 30%). Serious TRAEs were reported in 27 pts (16%); the most frequent was pneumonitis (n = 5; 3%). Nine pts (5%) discontinued pralsetinib due to a TRAE and one patient ( < 1%) died due to a TRAE ( pneumocystis jirovecii pneumonia) following 44 days ( < 3 cycles) on pralsetinib. Conclusions: In this updated analysis including more pts, pralsetinib continues to be efficacious with a manageable safety profile in pts with RET-altered TC. Clinical trial information: NCT03037385.

Abstract Richter’s syndrome (RS) arising from chronic lymphocytic leukemia (CLL) is a striking example of an aggressive malignant histology that emerges from indolent cancer. RS is a major barrier to disease control in CLL and is associated with poor clinical outcomes and limited survival. The genetic basis of RS is poorly understood, and its relationship to the antecedent CLL remains incompletely characterized. To study RS, we performed whole-exome sequencing (WES) on samples collected from 52 patients with RS of diffuse large B cell lymphoma (DLBCL) histology. For this genomic characterization, samples from 42 patients were analyzed as ‘trios’ (matched germline, CLL and RS tissue DNA) and those from 10 as ‘duos’ (matched CLL and RS DNA). Beyond addressing contamination of CLL DNA in the germline sample, we developed methods for discriminating between the RS and CLL clones which often coexist in the same samples. The discovery cohort revealed that RS and CLL were clonally-related in 45/52 (87%) cases based on WES analysis, with a distinct RS clone emerging from a CLL subclone. The remaining 13% were determined to be clonally unrelated. RS clones presented ~3x higher rates of additional mutations than the ancestral CLL clones from which they developed. We identified novel RS somatic driver mutations (in IRF2BP2, SRSF1, B2M, DNMT3A and others), a high rate of copy number variations with recurrent deletions (e.g., del(17p) [TP53], del(13q14.3), del(7q36), and del(15q13.11) [MGA], del(9p21.3) [CDKN2A/B], del(16q12.2)), focal amplifications (amp(7q21.2) [CDK6], amp(8q24.2) [RECQL4, MYC], amp(13q31.2) [ERCC5], and frequent whole genome duplication. To further investigate RS and CLL clonal evolution, we performed single-cell RNA-sequencing on biopsies at the time of RS diagnosis in 5 individuals with clonally related transformation. Using our novel tool, CNVSingle, we inferred allele specific single-cell copy number alterations, yielding cluster-specific copy number profiles that matched the WES results of individual subclones of the RS and CLL populations. This enabled mapping genetic clones to specific expression patterns. Finally, we devised and tested a methodology that uses cfDNA for early detection of emerging Richter’s disease and have successfully identified Richter‘s tumor DNA in the blood several months prior to the clinical diagnosis. Our study thus defines drivers, distinct molecular subtypes and evolutionary path to RS and suggests strategies for its improved detection. Citation Format: Erin M. Parry, Ignaty Leshchiner, Romain Guièze, Connor Johnson, Eugen Tausch, Sameer Parikh, Camilla Lemvigh, Conor Messer, Daniel Rosebrock, Filippo Utro, Chaya Levovitz, Kahn Rhrissorrakrai, Matthew Davids, Raquel A. Jacobs, Kara Slowik, Julien Broseus, Shanye Yin, Shuqiang Li, Geoff Fell, Ziao Lin, Binyamin A. Knisbacher, Neil Ruthen, Dimitri Livitz, Christof Schneider, Jialin Ma, Julian Hess, Laura Z. Rassenti, Thomas J. Kipps, Nitin Jain, William Wierda, Florence Cymbalista, Neil E. Kay, Kenneth J. Livak, Brian P. Danysh, Chip Stewart, Donna Neuberg, Jennifer R. Brown, Laxmi Parida, Stephan Stilgenbauer, Gad Getz, Catherine J. Wu. Evolutionary history of transformation from chronic lymphocytic leukemia to Richter’s syndrome [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4007.

AbstractBackgroundAn increasing demand of minimally‐invasive aesthetic procedures of the forehead concomitantly leads to higher numbers of adverse events. Adequate application of anatomical knowledge is required to increase safety and efficacy of different minimally‐invasive aesthetic procedures in this anatomical region.ObjectiveTo describe the layered anatomy of the forehead soft tissues with respect to their thicknesses and how they relate to different minimally‐invasive aesthetic treatments.MethodsA total of n = 85 healthy study participants (69 females and 16 males) with a mean age of 40.84 ± 10.9 years and a mean body mass index of 22.65 ± 2.6 kg/m2 were investigated with ultrasound‐based imaging to measure the thickness of different forehead soft tissues.ResultsThe mean overall soft tissue thickness of the forehead was measured to be 4.18 ± 0.7 mm for the entire study population. Increasing BMI values correlated statistically significantly with increasing thickness of all measured forehead soft tissues with exception of the frontalis muscle. On a statistically significant level, males showed thicker forehead soft tissues than females, with exception of the retrofrontalis fat and the frontalis muscle.ConclusionOn basis of the findings obtained in this study, basic treatment principles can be derived and improved for the injection of neuromodulators, hyaluronic acid as well as the application of polydiaxonane (PDO) threads and micro‐focused ultrasound. Precise knowledge and thorough understanding of the layers and soft tissues of the forehead is required to guarantee safe and effective procedures in this aesthetically important facial region.

Background: Type I tibial spine fractures are non-displaced or minimally displaced (≤ 2mm displacement) fractures of the tibial eminence and ACL insertion traditionally managed nonoperatively with immobilization. Hypothesis/Purpose: We hypothesized that type I fractures do not carry significant risk of associated injuries and therefore do not require additional interventions aside from immobilization. Methods: We reviewed 52 patients classified by their treating institution with type I tibial spine fractures presenting between January 1, 2000 and January 31, 2019 at 10 institutions. Patients of age ≤ 18 years with pre-treatment plain radiographs and at least one year of follow-up were included. Data was collected on patient demographics, injury mechanism, treatment details, presence of concomitant injuries, range of motion (ROM) at final follow-up, treatment complications, and any return to the operating room for the injured knee. Pre-treatment imaging was reviewed by four authors to assess agreement of classification among the treating institutions. Patients were subclassified into two groups to ensure outcomes represented classic type I fracture patterns. Any patient with universal agreement among the four authors that the fracture did not appear consistent with a type I classification were assigned to Type 1+ Group (T1+). All other patients were assigned to the True Type I Group (TT1). We evaluated concomitant injury, need for operative intervention, and treatment outcomes overall and for each group independently. Results: 48 patients met inclusion criteria. 40/48 were TT1 fractures, while 8/48 were T1+ fractures, indicating less than universal agreement among sports specialists in classification of these fractures. Among TT1 patients, 7 of 40 (18.4%) underwent surgical treatment, though this represented 35.7% (5/14) of those who had undergone pretreatment advanced imaging. In the T1+ group, 6 of 8 (75%) underwent surgical treatment, 50% of whom (3/6) had pretreatment advanced imaging. Overall, twelve of 48 patients (25%) had concomitant injuries, nine TT1 patients and three T1+ patients (p=0.77), with 7 concomitant injuries requiring additional surgical management. Conclusions: Classification of type I fractures can be challenging. Nonetheless, a substantial percentage of patients with these fractures (>20%) were found to have concomitant injuries by advanced pretreatment imaging, with surgical management indicated in 58.3% of these patients. Contrary to traditional thought, type I tibial spine fractures do carry a risk of associated injuries. Simple cast immobilization may not be the ideal treatment in all cases. Advanced imaging would be beneficial for those whose plan of care may initially be non-operative treatment.

Background: When operative treatment is indicated, tibial spine fractures can be successfully managed with open or arthroscopic reduction and internal fixation. Hypothesis/Purpose: We hypothesized both approaches can lead to satisfactory outcomes for fracture healing, but that open treatment without preoperative advanced imaging can potentially lead to missed concomitant injuries. Methods: We performed an Institutional Review Board (IRB)-approved retrospective cohort study of pediatric tibial spine fractures presenting between January 1, 2000 and January 31, 2019 at 10 institutions. Patients were categorized into two cohorts based on treatment: arthroscopic reduction and internal fixation (ARIF) and open reduction and internal fixation (ORIF). Surgical outcomes, the incidence of concomitant injuries, and surgeon demographics were compared between groups. Results: There were 477 patients with tibial spine fractures who met inclusion criteria, 420 of whom (88.1%) were treated with ARIF, while 57 (11.9%) were treated with ORIF. Patients treated with ARIF were more likely to have an identified concomitant injury (41.4%) compared to those treated with ORIF (24.6%, p=0.021). Patients treated with ARIF were also more likely to have pre-treatment MRI (41.7% vs. 22.8%, p =0.010). Most concomitant injuries (74.5%) required surgical intervention. The most common treatment complications included arthrofibrosis (6.9% in ARIF patients, 7.0% in ORIF patients, p=1.00) and subsequent ACL injury (2.1% in ARIF patients and 3.5% in ORIF, p=0.86). The rate of complications, return to the operating room, and failure to return to full range of motion were similar between groups. Twenty surgeons with sports subspecialty training completed 85.0% of ARIF cases; the remaining 15.0% were performed by 12 surgeons without additional sports training. The majority (56.1%) of ORIF cases were completed by 14 surgeons without sports subspecialty training. Conclusion: This is the largest study comparing ARIF to ORIF in pediatric tibial spine fractures. This study demonstrated no difference in outcomes or nonunion following ARIF or ORIF for pediatric tibial spine fractures. There were significantly higher rates of concomitant injuries in patients treated with ARIF, however, these patients also had a higher rate of pre-treatment MRI. The majority of these concomitant injuries (74.5%) required surgical intervention. Pre-treatment MRI should be considered in the workup of tibial spine fractures to increase identification of concomitant injury. Concomitant injuries may be missed in tibial spine fractures treated with an open approach, especially in cases where preoperative advanced imaging is not obtained. Surgeon preference and training may impact treatment approach and identification and treatment of concomitant injury.

Introduction There is emerging evidence supporting the use of the radial artery (RA) as a preferred secondary conduit for coronary artery bypass grafting (CABG) as it is associated with higher rates of graft patency at 5 years when compared with saphenous vein grafts (SVG). The modified Allen’s test (MAT) is traditionally regarded as the standard of care in the assessment of ulnar artery (UA) patency prior to RA harvesting. Unfortunately, due to high false-positive rates, a substantial number of pre-CABG patients are found to have an abnormal MAT despite normal UA patency, resulting in inappropriate exclusion from RA harvesting. The SVG is generally used in its place when this occurs, resulting in potentially lower rates of long-term graft patency. Methods and analysis The CAPITAL iRADIAL-CABG trial is currently enrolling participants 18 years of age or older undergoing CABG for whom the treating physician is considering the use of an RA conduit. Eligible patients will be randomised in a 1:1 fashion to MAT or smartphone-based photoplethysmography application assessment to assess collateral palmar circulation prior to RA harvesting. The primary outcome of the trial is the use of the RA as a conduit during CABG. The primary safety outcome is postoperative palmar ischaemia as determined by clinical assessment or requirement of vascular intervention. Secondary outcomes include vascular complications, early graft failure, need for rescue percutaneous coronary intervention during the index hospitalisation and a composite cardiovascular outcome of myocardial infarction, stroke and cardiovascular death prior to discharge from hospital. A total of 236 participants are planned to be recruited. Ethics and dissemination The study was approved by the Ottawa Heart Science Network Research Ethics Board (approval number 20180865-01H). The study results will be disseminated via conference presentations and peer-reviewed publications. Trial registration number NCT03810729.