Citations

666 Background: In the phase 3 CABINET trial (NCT03375320), cabozantinib (CABO) significantly prolonged median progression-free survival (PFS) compared to placebo (PB) in patients with advanced, previously treated, progressive extrapancreatic NET (epNET) [HR 0.38 (95% CI, 0.25-0.59, P<0.0001)] and pancreatic NET (pNET) [HR 0.23 (95% CI, 0.12-0.42, P<0.0001)] (Chan et al., NEJM, 2024). In this analysis, we focus on outcomes of patients with epNET arising in the GI tract. Methods: Patients with locally advanced or metastatic epNET or pNET were randomized 2:1 in separate cohorts to receive CABO 60 mg daily vs PB. The epNET cohort included patients with tumors arising in the GI tract (not including pancreas), lung, unknown primary, and other rare primary sites. In this subgroup analysis of the epNET cohort, patients with GI NET were included. Eligibility included progression by RECIST within 12 months (mo) prior to registration, ≥ 1 prior systemic therapy. Primary endpoint: PFS by blinded independent central review (BICR). Secondary endpoints: objective response rate, overall survival, safety. Results: 116 of the 203 patients in the epNET cohort had GI NET (CABO, n=70; PB, n=46). Median age was 66 yrs; females: 46%; G1/G2/G3/unknown grade: 35%/57%/6%/2%. ECOG performance status: 0/1-2: 43%/57%. White race: 86%. The most common primary tumor locations were ileum/cecum (54%), small intestine with location not specified (20%); non-cecum colon or rectum (11%), stomach (4%); duodenum (3%); jejunum and nonspecified midgut site (3% each). Prior systemic therapies included somatostatin analogs (SSA) (100%), everolimus (59%); Lu-177 dotatate (77%); temozolomide +/- capecitabine (16%). In patients with GI NET, CABO was associated with improved PFS by BICR compared to PB (stratified HR, 0.50; 95% CI: 0.28-0.88, 1-sided stratified log-rank P=0.007). Median PFS with cabozantinib was 8.5 mo (95% CI, 6.0-16.7) compared to 5.6 mo (95% CI, 3.9-11.0) with PB. CABO demonstrated potential benefit in patients with midgut GI NET and across clinical factors including grade, functional status related to hormone secretion, concurrent SSA use, and prior therapy with Lu-177 dotatate or everolimus. The most frequent grade 3/4 adverse events attributed to therapy with CABO included hypertension (19%), diarrhea (13%), fatigue (10%). Conclusions: CABO is associated with improvement in PFS compared to PB in patients with advanced GI NET. Potential benefit was observed across clinical factors including grade, functional status, concurrent SSA, and prior treatment. The safety profile for CABO in patients with GI NET is consistent with that previously reported. Support: U10CA180821, U10CA180882; U10CA180820 (ECOG-ACRIN), U10CA180868 (NRG Oncology), U10CA180888 (SWOG); Exelixis; https://acknowledgments.alliancefound.org . Clinical trial information: NCT03375320 .

TPS309 Background: Patients with oligometastatic colorectal cancer (CRC) often experience long-term progression-free survival and overall survival (OS) following aggressive local treatment of isolated metastases, especially in the liver. However, the effectiveness of local ablative therapies, such as microwave ablation (MWA) and stereotactic body radiation therapy (SBRT), in patients with inoperable limited metastatic CRC or those with additional metastases outside the liver or lungs, remains uncertain. Despite the historical use of local therapy for oligometastatic CRC, often influenced by provider bias rather than strong evidence, questions persist about the potential benefits of applying this approach to patients with more extensive disease. This trial aims to address this clinical challenge by evaluating the safety and efficacy of adding total ablative therapy (TAT) of all disease sites to standard systemic treatment in patients with limited metastatic CRC. Methods: A022101/NRG-GI009 is a randomized phase III study within the National Clinical Trials Network, set to enroll 364 patients with newly diagnosed metastatic CRC (BRAF wild-type, microsatellite stable). Patients with liver-only metastatic disease are excluded. Pre-registration during first-line systemic therapy induction is encouraged. Eligible lesions must be treatable with surgical resection, MWA, and/or SBRT. Patients without significant radiographic progression after 12-39 weeks of first-line systemic therapy, with 4 or fewer disease sites post-induction chemotherapy, will be randomized 1:1. Randomization will be stratified by the number of metastatic organ sites (1-2 vs. 3-4), timing of metastatic disease diagnosis (de novo vs. secondary), and the presence of metastatic disease outside the liver/lungs in at least one site. Patients in Arm 1 will receive TAT, targeting all metastatic sites with a combination of surgical resection, MWA, and/or SBRT, followed by standard systemic therapy. Patients in Arm 2 will continue with standard systemic therapy alone. The choice of systemic therapy is at the discretion of the medical oncologist and may include continued therapy, maintenance chemotherapy, or observation. The primary endpoint is OS, with secondary endpoints including event-free survival, treatment-related toxicities, and local recurrence. Exploratory biomarker analyses will also be conducted. The study requires 346 evaluable patients across the two arms to demonstrate an OS improvement with a hazard ratio of 0.7, providing 80% power with a one-sided alpha of 5%. The trial employs a group sequential design with two interim analyses (at 25% and 50% of events) to assess futility. The trial began in January 2023, and patient recruitment is ongoing. Clinical trial information: NCT05673148 .

Abstract Background Progress in clinical trials and drug development for paediatric perianal fistulising CD (pfCD) depends upon accurate, reproducible imaging to assess disease activity and measure treatment response. We evaluated the inter- and intra-rater reliability of existing radiologic disease activity indices and anatomical classification systems previously identified as appropriate for assessment of paediatric pfCD.1 Methods A retrospective cohort (N=50) of magnetic resonance imaging (MRI) exams representing a full spectrum of paediatric (&lt;18 years) perianal CD severity was selected by a single expert paediatric radiologist. Methods described by Zou2 were used to estimate sample size. Three separate radiologists (2 paediatric) blinded to clinical information assessed pfCD in the exams using the Magnetic Resonance Novel Index for Fistula Imaging in CD (MAGNIFI-CD), Van Assche Index (VAI), modified VAI (mVAI), Paediatric MRI based Perianal Crohn’s disease (PEMPAC) index, a visual analogue scale (VAS) of overall pfCD disease severity (range, 0-100 mm), as well as with the Park’s and St. James University Hospital anatomic classification systems. Two radiologists read all exams twice, separated by 2 weeks, and 1 radiologist read the exams once (250 total reads). Intra- and inter-rater reliability was evaluated using intraclass correlation coefficients (ICC; equivalent to weighted kappa). Precision of the ICC estimates was quantified with 95% confidence intervals (CIs) obtained using clustered bootstrapping. Degree of reliability was interpreted with benchmarks proposed by Landis and Koch3. Results Median age of children was 13.5 years (IQR 11.4-16.1), and 64% were male. Median Paediatric Crohn’s Disease Activity Index score at time of imaging was 17.5 (IQR 10-32.5). Substantial (ICC&gt;0.61) inter-rater reliability was observed for MAGNIFI-CD, VAI, and mVAI (Table 1), with the highest ICCs observed for the mVAI (0.72 [0.6 to 0.79]). Moderate (ICC&gt;0.41) inter-rater reliability was observed for PEMPAC, St. James University Hospital classification, and the VAS, and fair (ICC&gt;0.21) inter-rater reliability was observed for Parks classification. Intra-rater reliability was nearly perfect (ICC&gt;0.81) for the VAS, and substantial for all indices except for Parks classification, which had moderate (0.60 [0.44 to 0.75]) intra-rater reliability (Table 1). Conclusion Most existing multi-item MRI-based disease activity indices and the St. James Hospital classification were reliable for the assessment of paediatric pfCD in our cohort. Our preliminary results suggest that the disease activity indices may have utility to measure treatment effect in paediatric pfCD clinical trials. References 1.Crowley E, Ma C, Guizzetti L, Zou G, Lewindon PJ, Gee MS, et al. Recommendations for Standardizing MRI-based Evaluation of Perianal Fistulizing Disease Activity in Pediatric Crohn's Disease Clinical Trials. Inflamm Bowel Dis. 2024;30(3):357-69. 2.Zou GY. Sample size formulas for estimating intraclass correlation coefficients with precision and assurance. Statistics in Medicine. 2012;31(29):3972-398 3.Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics. 1977;33(1):159-74.

ABSTRACT Background Inclusion body myositis (IBM) is the most prevalent muscle disease in adults for which no current treatment exists. The pathogenesis of IBM remains poorly defined. In this study, we aimed to explore the interplay between inflammation and mitochondrial dysfunction in IBM. Methods The study population consisted of 38 IBM patients and 22 age‐ and sex‐matched controls without a myopathy. Mean age was 62.9 years (SD = 9) in IBM group and 59.7 (10) in controls. Bulk RNA sequencing, Meso Scale Discovery electrochemiluminescence (ECL), western blotting, histochemistry and immunohistochemistry were performed on frozen muscle samples from the study participants. Results We demonstrated activation of the NLRP3 inflammasome in IBM muscle samples, with the NLRP3 inflammasome being the most upregulated pathway on RNA sequencing, along with increased expression of NLRP3 and ASC proteins in IBM group. NLRP3 RNA levels most strongly correlated with TLR7 (correlation coefficient ρ = 0.91) and complement activation‐related genes, and inversely correlated with several mitochondria‐related genes among others. On muscle histopathology, there was increased NRLP3 immunoreactivity in both inflammatory cells and muscle fibres. Mitophagy is critical for removing damaged mitochondria and preventing the formation of a vicious cycle of mitochondrial dysfunction—NLRP3 inflammasome activation. Herein, we showed altered mitophagy, as witnessed by the elevated levels of p‐S65‐Ubiquitin, a mitophagy marker, in muscle lysates from IBM patients compared to controls (median of 114.3 vs. 81.25 ECL units, p = 0.005). The p‐S65‐Ubiquitin levels were most significantly elevated in IBM males compared to male controls (136 vs. 83.5 ECL units; p = 0.013), whereas IBM females had milder nonsignificant elevation compared to female controls (97.25 vs. 69 ECL units, p = 0.31). On muscle histopathology, p‐S65‐Ubiquitin aggregates accumulated in muscle fibres that were mostly Type 2 and devoid of cytochrome‐c‐oxidase reactivity. NLRP3 RNA levels correlated with p‐S65‐Ubiquitin levels in both sexes (males: ρ = 0.48, females: ρ = 0.54) but with loss of muscle strength, as reflected by the manual motor test score, only in males (males: ρ = 0.62, females: ρ = −0.14). Lastly, we identified sex‐specific molecular pathways in IBM. Females had upregulation of pathways related to response to stress, which could conceivably offset some of the pathomechanisms of IBM, while males had upregulation of pathways related to cell adhesion and migration. Conclusions There is activation of the NLRP3 inflammasome in IBM, along with altered mitophagy, particularly in males, which is of potential therapeutic significance. These findings suggest sex‐specific mechanisms in IBM that warrant further investigation.

Abstract Aims To evaluate clinical outcomes, echocardiographic features, and the efficacy and safety of sacubitril/valsartan compared to valsartan across age groups in the PARAGON-HF trial. Methods and results A total of 4796 participants ≥50 years of age with chronic heart failure (HF) and left ventricular ejection fraction (LVEF) ≥45% were divided into three age groups: &lt;65 years (n = 825), 65–74 years (n = 1772), and ≥75 years (n = 2199). Echocardiograms of 1097 patients were analysed in a standardized fashion at a core imaging laboratory. The primary composite outcome was total HF hospitalizations and cardiovascular (CV) death. Older patients were more likely to experience primary composite outcomes (compared to patients &lt;65 years, adjusted rate ratio [aRR] for ≥75 years: 1.39, 95% confidence interval [CI] 1.21–1.61), total HF hospitalization (aRR 1.27, 95% CI 1.09–1.49), and CV death (adjusted hazard ratio [aHR] 2.04, 95% CI 1.44–2.87). Age did not modify the effect of sacubitril/valsartan compared to valsartan on primary composite endpoint (pinteraction = 0.79) in the overall population or in those with LVEF ≤57%. Older adults randomized to sacubitril/valsartan were more likely to develop hypotension compared to those receiving valsartan (pinteraction = 0.026). Older patients had smaller left ventricular chamber sizes, higher LVEF, and were more likely to have abnormal measures of diastolic function. Conclusion Older patients with HF with preserved ejection fraction had higher event rates than younger patients, more adverse events overall, and more hypotension when treated with sacubitril/valsartan; however, the treatment benefits of sacubitril/valsartan were retained in older patients.

Importance Neoadjuvant therapy (NT) is an increasingly used treatment strategy for patients with localized pancreatic ductal adenocarcinoma (PDAC). Little research has been conducted on cancer care delivery during NT, and the standards for optimal delivery of NT have not been defined. Objective To develop consensus best practices for delivering NT to patients with localized PDAC. Design, Setting, and Participants This study used a modified Delphi approach consisting of 2 rounds of voting, and a series of virtual conferences (from October to December 2023) to reach expert consensus on candidate best practice statements generated from a systematic review of the literature and expert opinion. An interdisciplinary panel was formed including 47 North American experts from surgical, medical, and radiation oncology, radiology, pathology, gastroenterology, integrative oncology, anesthesia, pharmacy, nursing, cancer care delivery research, and nutrition as well as patient and caregiver stakeholders. Main Outcome and Measures Statements that reached 75% agreement or greater were included in final consensus statements. Results Of the 47 participating panel members, 27 (57.64%) were male, and the mean (SD) age was 47.6 (8.2) years. Physicians reported completing training a mean (SD) 14.6 (8.6) years prior and seeing a mean (SD) 110.6 (38.4) patients with PDAC annually; 35 (77.7%) were in academic practice. Final consensus was reached on 82 best practices for delivering NT. Of these, 38 statements focused on pre-NT practices, including diagnosis and staging (n = 15), evaluation and optimization (n = 20), and decision-making (n = 3); 29 statements defined best practices during NT, including initiation (n = 3), delivery of therapy (n = 8), restaging practices (n = 12), and management of complications during NT (n = 6); and 15 best practices were identified to guide treatment post-NT, focusing on surgery (n = 7), pathology (n = 4), and follow-up (n = 3). Conclusions Using a modified Delphi consensus technique, best practice guidelines were developed focusing on the optimal standards for delivering NT to patients with localized PDAC. Given the prognostic importance of completing multimodality therapy, efforts to standardize and optimize the delivery of NT represent an immediate opportunity to decrease care variation and improve outcomes for patients with PDAC. Future research should focus on validating and implementing best practice standards into clinical practice.

Abstract The field of infectious diseases (ID) offers a rewarding career path and is widely viewed as an essential subspecialty in medicine. However, in recent years, these positive aspects have been overshadowed by concerns surrounding low fellowship match rates, undercompensation, and burnout. The Infectious Diseases Society of America Fellowship Training Program Directors Committee met in 2023, discussed the future of ID as a specialty, and sought to develop strategies to highlight the value and opportunities of ID for future generations, as well as underscore the importance of and provide tools for positive messaging to trainees about the subspecialty. This paper presents ideas generated at this meeting and is meant to serve as a reference for ID training program directors, as well as the wider ID community, in uplifting and shaping the future of the field.

Abstract Introduction Pancreatic adenocarcinoma (PDA) will be the second leading cause of cancer related death by 2030 and patient response to chemotherapy is poor with a strong likelihood of cancer recurrence. While past studies have investigated pre- and post-chemotherapy patient samples, there is a paucity of studies looking at fresh, patient matched samples which allow us to observe interpatient heterogeneity in chemotherapy response. Methods Here, we study the effects of chemotherapy on five different patients using sc-RNA sequencing of matched treatment naïve and post treatment tissue biopsies to compare the effects of chemotherapy, not only on the tumor cells, but also on the tumor microenvironment – a key contributor to tumor survival and proliferation. We utilized the Seurat v4 pipeline and CellChat v2 to observe transcriptomic differences in epithelial cells, myeloid cells, t-Cells, and fibroblasts and their corresponding putative interactions in pre- and post- treatment states. Results Unsurprisingly, we found insufficient tumor epithelial cells post-treatment to perform further analysis on due to the intended cytotoxic effects of chemotherapy. Therefore, we turned our focus to the tumor microenvironment, where we had sufficient numbers of stromal and immune cells, to investigate the effects of chemotherapy. We identified that fibroblasts changed the most consistently across all patients in response to chemotherapy. The fibroblasts clustered into three distinct groups: an immunomodulatory group, a myofibroblastic and neurotropic group, as well as a mixed group expressing genes from all three categories. Interestingly, the neurotropic fibroblast signature was universally enriched after chemotherapy in all five patients, despite having a small and clinically heterogeneous cohort. Conclusions Through an analysis of each fibroblast group in the treatment naïve and post treatment categories, we observed that a specific set of fibroblasts become less myofibroblastic and increasingly neurotropic following treatment, leading us to posit that fibroblasts altered by exposure to chemotherapy may potentially contribute to a ‘pro-tumor’ environment that supports recurrence. To test this in vitro, we treated patient derived fibroblasts with Gemcitabine and used RTPCR to analyze their relative changes in gene expression. We specifically probed for genes that were definitive of myofibroblasts and neurotropic fibroblasts and saw that post-chemotherapy exposure, neurotropic genes such as NEGR1 and NFIA were upregulated. This validated our scRNA conclusions that fibroblasts become increasingly neurotropic following treatment and then differentially interact with their surrounding environment. In future studies, we will further analyze the role these neurotropic fibroblasts play in chemoresponse and tumor recurrence. Matched samples are critical to studies of chemotherapy effects on PDA due to the fact that they allow us to deconvolute one aspect of PDA heterogenity - interpatient heterogeneity - which is a large limitation in studies of this disease. Citation Format: Aylin Z Henstridge, Padma Kadiyala, Ahmed M Elhossiny, Jianhua Liu, Vaibhav Sahai, Nicole Peterson, Jorge Machicado, Richard Kwon, Allison Schulman, Erik Wamsteker, George Philips, Martin Fernandez-Zapico, Mark Truty, Costas Lyssiotis, Timothy Frankel, Filip Bednar, Marina Pasca di Magliano, Eileen S Carpenter. Neurotropic fibroblast population increases following exposure to chemotherapy in pancreatic adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr A062.