Citations

ABSTRACT Current laboratory testing for Lyme disease (LD) relies on serology. We evaluated the performance of standard two-tiered testing (STTT) and modified two-tiered testing (MTTT) algorithms using samples obtained from well-characterized patients with early LD in the U.S. East Coast and Upper Midwest. Participants with signs and symptoms of early LD (cases) and controls were enrolled by Lyme Disease Biobank. We compared the performance of four FDA-cleared STTT or MTTT algorithms using serum samples from 251 participants (107 cases, 69 with a convalescent draw; 144 endemic controls). At the initial blood draw, algorithm sensitivity ranged from 22% to 36%, with specificity ranging from 98% to 100%. MTTT algorithms showed higher sensitivity compared with STTT algorithms ( P ≤ 0.05). One STTT algorithm was less sensitive than the other ( P = 0.035), and there was no significant difference in sensitivity between MTTT algorithms. There was also discordance between algorithms; only 22 of the 45 samples classified as laboratory confirmed by Lyme Disease Biobank testing were positive using all algorithms evaluated. Likelihood of positive two-tiered serology among cases with a suspected erythema migrans (EM) skin lesion increased with longer lesion duration and/or when presenting with >1 constitutional symptom. Participants with suspected EM without constitutional symptoms were unlikely to test positive by any algorithm evaluated. Testing convalescent samples did not improve LD detection, and seroconversion was rare. While MTTT confirmed more early LD cases than STTT, all two-tiered algorithms evaluated were insensitive in this population. Novel diagnostics that improve laboratory confirmation for early LD are urgently needed. IMPORTANCE This study confirms that two-tiered serologic testing algorithms are insensitive in early Lyme disease, particularly within the first 2 weeks after symptom onset or when erythema migrans is not accompanied by constitutional symptoms. It also demonstrates that seroconversion is rare after antibiotic treatment. These results highlight the need for novel diagnostics for early Lyme disease that do not rely on serologic testing.

The 6th edition of the WHO Classification of Breast Tumours introduces both major and minor changes based on recent advances in our understanding of breast biology, developments in diagnostic modalities, identification of specific molecular targets and new treatment regimens necessitating modifications to pathology reporting and tumour biomarker categorisation. This review summarises the main changes that strive towards a classification of global relevance. In invasive carcinoma, predictive factors increasingly inform modern breast cancer treatment. The 6th edition provides an update on HER2 reporting categories following the DESTINY‐Breast 04 and 06 trials. Terminologies used to classify invasive tumours are clarified, with the term ‘variant’ now reserved for molecular/genetic alterations. Invasive lobular carcinoma (ILC) with extracellular mucin is recognised as a new diagnostic entity with prognostic implications. The diagnosis of mucinous carcinoma (MC) is reserved for mucin secreting carcinomas with grade 1 or 2 morphology and a favourable biomarker profile. The diagnosis of malignant phyllodes tumours requires only four of the original five adverse histological criteria. Classification of neuroendocrine tumours (NETs) is revised, recognising that the unified model, promoted in the 5th edition, is difficult to apply to the breast. New approaches to the classification of adenomyoepithelioma are discussed but the 5th edition system is broadly retained. A new section on ‘Small Diagnostic Samples’ outlines the merits of non‐operative biopsy diagnosis, the B coding system and the importance of multidisciplinary review. Changes to diagnostic practice and the emerging role of artificial intelligence, with advantages and challenges, are discussed in a new section on ‘Digital Pathology’.

Abstract Introduction: Epoxy fatty acid (EpFA) mechanisms of hormone therapy resistance (HTR) in ER+HER2- breast cancer (BC) are poorly understood. EETs are EpFAs that contribute to BC progression and HTR by promoting oxidative phosphorylation (OXPHOS). However, it remains unclear how EETs contribute to HTR. In this study, two fulvestrant resistant (FR) subclones of the letrozole resistant (LR) MCF-7AC1 line were isolated (termed LR/FR) and were incidentally resistant to the CDKi palbociclib (PR) (termed MCF-7AC1 LR/FR/PR or multiply resistant - MCF-7AC1 MR). These HTR cell lines exhibited CYP3A4 upregulation (2.3- to 4.3-fold) and increased cellular (±)14,15-EET levels, which were suppressed by biguanide treatment (P<0.05). Structure activity studies led to the design of hexyl cuban-1-yl biguanide (HCB) and fluorinated HCB derivatives C5F2-HCB and C6F3-HCB, which inhibited CYP3A4-mediated EET biosynthesis and growth of the HTR lines. HCB fluorination improved pharmacokinetics (PK) and toxicity. Methods: HCB and fluorinated HCBs were tested for impact on EET biosynthesis, OXPHOS, PK, and growth inhibition and reversal of hypoxia in the MCF-7AC1 MR tumor model. Results: Fulvestrant selection for MCF-7AC1 MR cell lines resulted in undetectable cyclin D1 and estrogen receptor (ERα) expression, while cyclin E1, CDK4, CDK6, CYP3A4, and c-MYC were upregulated (P<0.001). MCF-7 MR cells demonstrated 1.8, 1.4, and 1.2- fold higher levels of (±)8,9, (±)11,12, and (±)14,15-EET compared to parental MCF-7 cells (P<0.05). The most potent fluorinated HCB, C6F3-HCB, suppressed cellular levels of (±)8,9-EET, (±)11,12-EET, and (±)14,15-EET by 53-60% (P<0.029). The MCF-7AC1 MR cells were more potently inhibited by HCBs and fluorinated derivatives compared to the MCF-7 cell line. Comparing an MCF-7 MR line vs. MCF-7, HCB exhibited IC50 values of 4.1 vs. 7.0 uM, C5F2-HCB 10 vs. 25 uM, and C6F3-HCB 5.4 vs. 12 uM (P values all <0.05). C5F2-HCB exhibited the best PK and treatment of the MCF-7AC1 MR xenograft model showed reversal of hypoxia (P<0.05) and transient inhibition by C5F2-HCB (P=0.025 at 20 days). P/F also transiently inhibited this model (P=0.006 at 20 days). C5F2-HCB and P/F showed synergy in vitro (CI=0.46) leading to testing of C5F2-HCB/P/F in vivo enabled by acceptable toxicity of the triplet in mice. This combination showed synergy in vivo vs. standard of care palbociclib/fulvestrant by nonparametric statistical tests (Mann Whitney; P=0.0389; Kolmogorov-Smirnov; P=0.0473), providing a pathway for possible clinical development of the combination. Conclusions: MR BC cell lines exhibit upregulation of CYP3A4 and biosynthesis of EETs, indicating a role for EETs in HTR. The C5F2-HCB/P/F exhibits activity against the highly resistant MCF-7 MR xenograft with acceptable toxicity indicating an avenue for clinical development. Citation Format: Zhijun Guo, Jianxun Lei, Christian T. Wells, Allison M. Makovec, Andrew C. Yates, Swaathi Jayaraman, John R. Hawse, Joshua A. McCarra, Qing Cao, Michael J. Pryzbilla, Brenda L. Koniar, Beverly J. Norris, Craig M. Florey, Robert J. Schumacher, Michael A. Farrar, Kaylee L. Schwertfeger, Elizabeth A. Ambrose, Henry Wong, Gunda I. Georg, Antonino D'Assoro, Matthew P. Goetz, David A. Potter. Fluorinated cuban-1-yl biguanides overcome hormone therapy resistance to standard of care fulvestrant, and palbociclib [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(8_Suppl):Abstract nr LB196.

Background/Objectives: While doxorubicin (DOX) and trastuzumab (TRZ) improve overall survival in women with breast cancer, these two anti-cancer drugs increase the risk of developing heart failure. As a novel and largely unexplored approach, our aim was to evaluate whether the prophylactic use of the sodium-glucose co-transporter 2 inhibitor empagliflozin (EMPA), with and without the angiotensin converting enzyme inhibitor perindopril (PER), is cardioprotective in preventing DOX + TRZ-mediated cardiotoxicity. Methods: In a chronic in vivo murine model, female mice received prophylactic treatment with PER (3 mg/kg), EMPA (10 mg/kg), or EMPA + PER via oral gavage for a total of 3 weeks as a run-in period prior to weekly administration of DOX + TRZ (8 mg/kg and 3 mg/kg, respectively) intraperitoneally for an additional 3 weeks (total of 6 weeks). Results: In mice treated with DOX + TRZ, the left ventricular ejection fraction (LVEF) decreased from 75 ± 2% at baseline to 40 ± 4% at week 6. Prophylactic treatment with either PER, EMPA, or EMPA+PER improved LVEF to 58 ± 3%, 66 ± 3%, and 67 ± 4% at week 6, respectively (p < 0.05). Histological analyses confirmed significant disruption of myofibrils, vacuolization, and loss of sarcomere integrity in the DOX + TRZ-treated mice. Prophylactic administration with PER, EMPA, or EMPA + PER, however, improved myofibril integrity at week 6 in mice receiving DOX + TRZ. Finally, although the Bax/Bcl-xL ratio was significantly elevated by 1.5-fold in mice treated with DOX + TRZ, this marker of apoptosis was attenuated by prophylactic treatment with either PER, EMPA, or EMPA + PER. Conclusions: Prophylactic administration of EMPA mitigated adverse cardiovascular remodeling in a chronic in vivo model of DOX + TRZ-mediated cardiotoxicity.

Background: Stable osteochondritis dissecans (OCD) lesions are primarily treated nonoperatively. Nonoperative treatment includes several recommendations, including the use of an unloader brace. However, little is known about the clinical effectiveness of unloader bracing and its influence on OCD healing, return to sports, and patient-reported outcomes (PROs). The purpose of this investigation was to evaluate the impact of unloader bracing on patients with stable medial femoral condyle (MFC) OCD lesions treated nonoperatively. Purpose: To investigate the influence of valgus unloader bracing on the success of treating stable MFC OCD with nonoperative treatment strategies. Study Design: Cohort study; Level of evidence, 2. Methods: The authors used a prospective cohort of patients receiving nonoperative care for stable MFC knee OCD lesions. The primary variable of interest was the efficacy of bracing. The primary outcomes were transition from nonoperative care to surgical intervention, return-to-play (RTP) clearance, and PROs. Bivariate testing was used to determine if there were differences between groups. Chi-square testing was used to determine if there were differences in rates of transition to surgery by group. The timing of the transition by each group was assessed using a Wilcoxon rank-sum test, given the nonparametric nature of the data. Kaplan-Meier survival analysis was used to calculate time at risk, incidence rate, and survival times for each group. Results: A total of 185 knees (bracing group: 123 [66.5%] knees; no-bracing group: 62 [33.5%] knees) were analyzed. Overall, 142 (76.8%) knees were successfully treated nonoperatively. Transition to surgery occurred in 43 (23.2%) knees. There were no differences in transition to surgery by groups, with no differences seen by group. Of the knees that did not transition to surgical care, 65 (71.4%) in the bracing group and 38 (74.5%) in the no-bracing group received RTP clearance ( P = .693). PRO scores were similar between the 2 groups at the time of RTP clearance. Conclusion: The inclusion of an unloader brace in the nonoperative treatment for stable MFC OCD lesions did not decrease the likelihood of patients undergoing surgical intervention or improve their PRO scores at the time of RTP clearance. Registration: NCT02771496 (ClinicalTrials.gov identifier).

Abstract We evaluated outcomes by management type for patients with stage IA nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) in the Global NLPHL One Working Group retrospective database of 2243 patients with stages I to IV disease diagnosed from 1992 to 2021 at 38 international institutions. A total of 779 patients had stage IA disease with median age of 35 years (range, 3-89) and median follow-up of 6.1 years. The 6-year progression-free survival (PFS) and overall survival were 86.3% and 97.7%, respectively. Outcomes were analyzed for the 2 groups: complete resection and unresected disease. Patients with a complete resection and observation alone (n = 99) had a 6-year PFS of 65.5% vs 90.5% for those who received radiotherapy (RT) (n = 53). Patients with unresected disease (n = 627; 80.5%) had a 6-year PFS of 62.0% for rituximab alone (n = 31), 89.6% for RT alone (n = 325), 76.8% for ABVD (doxorubicin, bleomycin, vinblastine, dacarbazine) alone (n = 40), and 94.3% for ABVD plus RT (n = 130). A total of 127 patients relapsed (16.3%), of which 25 (19.7%) had transformation. Our analysis suggests the following: (1) RT improves the PFS in patients with completely resected disease; (2) rituximab or ABVD alone does not appear to achieve a durable response; and (3) chemotherapy was not observed to add additional PFS benefit when used in combination with RT. Thus, for stage IA NLPHL, RT alone is likely sufficient for definitive treatment.

Abstract Multiple Myeloma is the second most common hematologic malignancy among US adults and remains incurable. Immunotherapies, including bispecific T cell engagers (BiTEs) targeting BCMA, have greatly improved outcomes. However, a significant fraction of patients still fail to respond, or develop resistant disease. Conventional models of T cell cytotoxicity focus on delivery of perforin- and granzyme-containing granules following antigen recognition and T cell activation, an inefficient mode of killing that requires effector-to-target cell contact. Activated T cells, however, also secrete cytokines capable of diffusing and acting on distant targets. This raises the possibility of paracrine killing, in which these cytokines induce tumor cell death independently of cell-cell contact.Tumor necrosis factor (TNF) is a key cytokine released during T cell activation and is unique in that it can drive either cell survival or cell death. Although most cells default to cell survival and NFkB-mediated inflammation, several modulators can shift this survival signaling toward cell death. We therefore hypothesized that sensitizing Myeloma cells to TNF could enable T cell paracrine killing and enhance the efficacy of anti-Myeloma T cell immunotherapies.To test this, we first established an in vitro model of clinical response to Teclistamab, a BCMA-directed BiTE, using Multiple Myeloma cell lines that displayed sensitive, intermediate, or resistant responses to T cell killing. Combining these data with assays of cytokine sensitivity and receptor expression, we found that susceptibility to TNF-mediated cell death was a major determinant of Teclistamab sensitivity. This correlation was further supported by reduction or complete abrogation of Teclistamab T cell killing of sensitive Myeloma cell lines when soluble TNF was neutralized from these co-cultures using monoclonal antibodies. Pharmacologic inhibition and CRISPR-mediated deletion of known regulators of TNF survival-signaling further sensitized Myeloma cells to both TNF and T cell killing. In the absence of these regulators, BCMA-negative myeloma targets retained sensitivity to Teclistamab, supporting the idea that the main mechanism of cell death was indeed paracrine killing.Together, these findings establish a direct link between TNF sensitivity and T cell-mediated killing of Myeloma cells, and support TNF-driven paracrine killing as a dominant mechanism of response to Teclistamab. Enhancing this TNF-mediated death signaling may therefore represent a strategy to overcome resistance and improve clinical efficacy of T cell-based immunotherapies in Multiple Myeloma. Citation Format: Allison Carr, Elise Sintim-Aboagye, Adrian Ting, . TNF-driven paracrine killing determines the cytotoxic efficacy of Teclistamab in Myeloma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 1636.

Abstract Large Language Models (LLM) are being widely adopted into the medical field for their impressive ability to analyze and summarize large amounts of text data. These models enable clinicians and researchers to extract meaningful insights from complex datasets and may assist with decision making. Here we present our workflows and application of LLM for the interpretation and summarization of clinical data related to CAR-T cell therapy. Using an LLM (Gemini 2.5 pro) in the Google Cloud Computing (GCP) environment, two applications were developed to analyze CAR-T cell therapy clinical data: 1) extracting and summarizing CRS and ICANS event-related data to streamline the compliance team workflow, and 2) identifying features available at time of CAR-T infusion able to classify patients into high- or low-monitoring needs 14 days post CAR-T. Patient data (vitals, labs, hematology notes, and EKGs) were extracted from the electronic medical record (EMR) using Google BigQuery into SQL tables in GCP. For each application, relevant data fields were retrieved, formatted into JSON objects, and embedded in the LLM prompt for context-aware processing. Both applications have undergone iterative prompt engineering after analyzing the LLM output against ground truth data in the EMR. For the application extracting and summarizing CRS and ICANS events, the LLM was optimized on Mayo Clinic Rochester data. When compared to the IEC compliance database, the LLM achieved 100% accuracy and F1 score for CRS events, and 96% accuracy and 82% F1 score for ICANS events. The match rate for CRS and ICANS grades were 83% and 89% respectively. We applied the same LLM to Mayo Clinic Arizona (MCA) and Mayo Clinic Florida (MCF) cases, who document clinical notes and toxicity flowsheet differently, and achieved an accuracy (MCA: 93%, MCF:93%) and F1 score (MCA: 96%, MCF: 96%) for CRS and accuracy (MCA: 81%, MCF:82%) and F1 score (MCA: 76%, MCF: 75%) for ICANS. LLM was able to capture events missed by manual reviews. For most of the discrepancies where compliance team final adjudication is needed, LLM will be updated to flag discrepancies for review by the compliance team. For the application related to the monitoring needs 14 days post CAR-T, the LLM identified 5 categories predictive of high or low monitoring needs post CAR-T infusion (disease status, inflammatory and tumor burden markers, hematologic status, renal function and performance status). Our model achieved a sensitivity of 85.7%, specificity of 23.8%, and F1 score of 65.5% for our first cohort, compared with data extracted by the LLM from the EMR. For our second cohort, with demographics statistically similar to cohort 1 and using the same 5 categories, the LLM achieved a sensitivity of 83.3%, a specificity of 28.6%, and F1 score of 65.4%. Our workflow and applications of LLM’s provide examples and guidance to others interested in applying LLM’s for clinical and research applications. Citation Format: Emmanuel Contreras Guzman, Matthew Jankowski, Andre De Menezes Silva Corraes, Malvika Gupta, Monica L. Shaw, Madiha Iqbal, Talal Hilal, Saurabh Chhabra, Ricardo Daniel Parrondo, Jody K. Mclean, Kim R. Riester, Kayla Joseph, Melinda Tan, Holly Ross, Cleyonia Barnett, Sylvia Carter, Semy Girmay, Rachel Wolan, Milana Ramsey, Christian Downhour, Kristy Morgan, Shae Sibley, Erica Rushing, Lucy Holmes, Allison Burgstahler, Stephen M. Ansell, Hassan Alkhateeb, Matthew Hathcock, Ramona Bruno, Allison C. Rosenthal, Hemant Murthy, Patrick B. Johnston, Jonas Paludo, Yi Lin. Applications of large language models to CAR-T cell therapy clinical data using Google cloud computing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 2740.