Citations

Abstract Endoscopic sleeve gastroplasty (ESG) facilitates 13.6%–16.2% total body weight loss (TBWL) at 12 months, but falls short of that seen with surgical vertical sleeve gastrectomy, in part owing to the retention of the gastric fundus. In adults with obesity, gastric fundal mucosal ablation (GFMA) reduces fasting plasma ghrelin (FPG), hunger, cravings, and accommodation. Combined GFMA-ESG could improve TBWL. This study aimed to evaluate the effectiveness and safety of sequential GFMA followed by ESG in adults with obesity, building on previously published 6-month results of GFMA alone. This was a prospective, first-in-human, two-phase clinical trial. Ten participants underwent GFMA, followed by ESG at month 6, and were followed for 12 months post-ESG (18 months total). GFMA was performed using hybrid argon plasma coagulation to lift and ablate the entire gastric fundal mucosa. ESG was performed using standard full-thickness endoscopic suturing of the gastric body. The primary end point was TBWL; secondary end points were safety and changes in FPG, maximum tolerated volume (MTV), and validated appetite questionnaires. Mean TBWL was 22.5% (SD 8.3%) at month 18. Hunger-related behaviors and eating self-efficacy showed sustained improvements. FPG was decreased at month 6 and returned toward baseline by month 18, while MTV remained suppressed. No serious adverse events occurred. Sequential GFMA-ESG is safe and induces substantial weight loss, reduced MTV of ingested nutrients, and improved behavioral measures. This combination approach builds on prior traditional ESG and GFMA-only results and may represent a promising advancement of endoscopic therapeutic options for weight loss.

Abstract Introduction: The Duffy null variant (genotype or phenotype) is associated with lower circulating absolute neutrophil counts (ANC) without increased risk for infection. It is found in ~66% of people identifying as Black or African American vs <1% of people of Asian or European ancestry. Many ANC reference intervals (RI) are not representative of the Duffy null population. There are no adult Duffy null WBC RI and no pediatric Duffy null ANC or WBC RI. Thus, we aimed to assess Duffy null ANC and WBC distributions as well as develop WBC and ANC RI for adults and pediatrics. Methods: Twenty-three sites across the United States collected samples with all sites excluding participants with conditions or medications that could impact ANC or WBC. Only Duffy null participants were included. Sex, race, ethnicity, age, sample collection type, practice setting, Duffy testing method, ANC, and WBC were recorded. The non-parametric method for determining lower limit of normal (LLN), upper limit of normal (ULN), and 90% confidence intervals (CI) around the limits was performed according to the Clinical and Laboratory Standards Institute guidelines. Specific ULN and LLN are not reported as these are preliminary data. The Mann-Whitney U test was used to compare sex and prior data; differences by age groups were assessed with Kruskal-Wallis test. Results: 316 participants 18+ years-old (y/o) were assessed of whom 62.3% (n=197) are female, 97.5% (n=308) identified as Black or African American, and 94.9% (n=300) identified as non-Hispanic. Median age was 47 y/o (IQR: 32-60.5). Median ANC was 2600/uL (IQR: 1860-3530; range: 400-7400); 28.6% (n=90) of participants had ANC <2000/uL, 13.6% (n=43) had ANC <1500/uL, and 2.5% (n=8) had <1000/uL. The 90% CI around the LLN was 810-1070/uL and 5570-7130/uL around the ULN. Consistent with prior data, there was a difference in median ANC by sex (male: 2400/uL; female: 2710/uL; p=0.02). There was no significant difference between this ANC data and previously published Duffy null ANC data (p=0.28). Median WBC was 5.4x109/L (IQR: 4.4-6.5; range: 2.10-11.64) with 4.1% (n=13) of participants with WBC <3.0x109/L. The 90% CI around the LLN is 3.68-4.30x109/L and 11.02-12.97x109/L around the ULN. 515 participants between 0-17 y/o were assessed with 51.8% (n=267) females, 94.8% (n=488) identified as Black or African American, and 94.0% (n=484) identified as non-Hispanic. Among pediatric participants, 56.8% (n=291) had ANC <2000/uL, 38.7% (n=198) had ANC <1500/uL, and 14.4% (n=74) had ANC <1000/uL. For those <1 y/o (n=29), median ANC was 950/uL (IQR: 840-1360; range: 111-3910). There are currently too few samples to predict ULN and LLN. Median WBC was 8.85x109/L (IQR: 7.03-10.16; range: 4.17-13.53). For those 1-5 y/o (n=143), median ANC was 1735/uL (IQR: 1100-2550; range: 207-5810) with a 90% CI around the LLN of 207-820/uL and 4020-5810/uL around the ULN. Median WBC was 6.72x109/L (IQR: 5.64-8.25; range: 3.68-12.97). For those 6-11 y/o (n=128), median ANC was 1590/uL (IQR: 1090-2470; range: 420-5490) with a 90% CI around the LLN of 420-910/uL and 4340-5490/uL around the ULN. Median WBC was 5.42x109/L (IQR: 4.45-6.70; range: 2.80-10.50). For those 12-17 y/o (n=215), median ANC was 2190/uL (IQR: 1460-2930; range: 204-5850) with a 90% CI around the LLN of 540-930/uL and 4350-5510/uL around the ULN. Median WBC was 5.06x109/L (IQR: 4.26-6.20; range of 2.04-9.91). There is a significant difference in ANC by age category (p<0.0001). Conclusion: This is the first report of healthy pediatric Duffy null ANC and WBC data and the first large-scale verification of adult Duffy null ANC and WBC data. Final RI are expected in September 2025. Among adults with the Duffy null phenotype, ANC LLN are likely between 810-1070/uL. Pediatric ANC LLN are likely as low as 207-820/uL (1-5 y/o), 420-910/uL (6-11 y/o), and 540-930/uL (12-17 y/o). These findings redefine “normal” as a significant proportion of healthy participants have ANC or WBC below current RI or below thresholds typically defined as disease. Limitations include heterogeneous sample populations and collection methods. Future analyses will assess differences between collection sites or methods. Ultimately, this work lays the foundation for a more scientifically sound and equitable approach to medical care by ensuring that RI accurately reflects health for the entire community. Healthcare systems are strongly encouraged to adopt Duffy null-specific ANC and WBC RI.

ABSTRACTUniparental Disomy (UPD) occurs when both copies of a chromosome or chromosomal segment originate from only one parent. Mosaic genome‐wide UPD (mos gwUPD) is typically identified in cases of fetal demise and placental dysplasia or in prenatal cases, where imprinting effects are associated with abnormal ultrasound findings. Children with mos gwUPD and clinical features due to UPD‐associated imprinting effects (especially Beckwith‐Wiedemann syndrome) have been reported; however, reports of adults with mos gwUPD are rare. Here we describe mos gwUPD in two apparently healthy pregnant adult women. Carrier testing noted variants with skewed allelic ratios outside of the normal heterozygous range, prompting further testing. Single nucleotide polymorphism (SNP) microarray identified mosaicism for gwUPD in both individuals, present at 85% and 90%, respectively, in blood, with varying percentages in other tissues. Neither woman displayed clinical features that would be expected with gwUPD at the time of testing, although retrospective careful personal history was consistent. Both women had uneventful pregnancies and delivered full‐term healthy infants. These two cases demonstrate that mos gwUPD can be an incidental finding identified in apparently healthy adult women. Clinical follow‐up is important for tumor monitoring, genetic counseling, and monitoring of future pregnancies due to mos gwUPD in the maternal endometrial tissue.

Abstract Fibrolamellar carcinoma (FLC) is a rare, usually lethal primary liver tumor that affects children, adolescents and young adults. Sequencing of FLC tumors in hepatocytes reveals that in 99% of the patients there is one recurrent genomic alteration: A deletion of 400 kB. This produces DNAJB1::PRKACA, a fusion of the first exon of DNAJB1 with the 2nd – 10th exons of PRKACA, the catalytic subunit of protein kinase A (PKA). PKA exists as a holoenzyme of two catalytic subunits and two regulatory subunits. The regulatory subunit both inhibits the catalytic and localizes it in the cell. Calibrated mass spectrometry shows that in normal liver there is always an excess of regulatory>catalytic subunits, but in the adjacent FLC tumor tissue there is an excess of catalytic>regulatory subunits. Different biochemistry assays and proximity ligation reveal both free catalytic, unbound to regulatory subunits, and an increase of kinase activity in the tumor cells. Much of the increase of catalytic subunit is in the nucleus. Transducing primary human hepatocytes (PHH) with DNAJB1::PRKACA is sufficient to recapitulate the transcriptome of FLC tumors. Transduction of PHH with just the wt PRKACA is also sufficient to recapitulate the transcriptome of FLC tumors. Thus, just increasing the level of kinase is sufficient, there is nothing special about the fusion domain. From our tissue repository we have four patients who have a tumor that looks like FLC but does not have a fusion to the catalytic subunit. The only alteration in these patients is loss of regulatory subunit. The transcriptome of these patient tumors is indistinguishable from that of classic DNAJB1::PRKACA FLC in hepatocytes. Additionally, we have a few dozen patients who have either DNAJB1::PRKACA or another fusion, ATP1B1::PRKACA in the ductal cells of their liver (producing cholangiocarcinomas) or ductal cells of their pancreas (producing IOPN, Intraductal Oncolytic Pancreatic Neoplasms). The transcriptome of these patients clusters with the transcriptome of the FLC patients with DNAJB1::PRKACA in the hepatocytes. A functional precision medicine drug repurposing screen found that the EC50 of the response of freshly resected tumors from patients to a wide panel of drugs is the same as that of FLC patients with DNAJB1::PRKACA in their hepatocytes. Based on sequencing one could conclude that patients with deletion of regulatory subunit in the hepatocytes, or expression of DNAJB1::PRKACA in the hepatocytes, or expression of DNAJB1::PRKACA or ATP1B1::PRKACA in the cholangiocytes or pancreatic ductal cells are at least three distinct diseases. An analysis of the cell biological changes reveals that they all of an increase of the ratio of catalytic:regulatory subunit, they have an increase of catalytic subunit in the nucleus, and these all result in the same changes of transcriptome and the same drug-response profile. Thus, looking beyond sequencing to the cellular changes leads to a different conclusion, that maybe they should be considered the same disease. Citation Format: Sanford Simon, Mahsa Shirani, David Requena, Denise Ng, Gadi Lalazar, Solomon Levin, Michael S. Torbenson, Aatur D. Singhi, Henrik Molina, Charles M. Rice, Philip Coffino, Barbara A. Lyons. Precision medicine for the fusion protein driven cancer, fibrolamellar carcinoma (FLC): Beyond sequencing [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pediatric Cancer Research; 2024 Sep 5-8; Toronto, Ontario, Canada. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl):Abstract nr B022.

PURPOSE Long-term outcomes of patients with stage I human epidermal growth factor receptor 2 (HER2)–positive breast cancer receiving adjuvant trastuzumab emtansine (T-DM1) remain undefined, and prognostic predictors represent an unmet need. METHODS In the ATEMPT phase II trial, patients with stage I centrally confirmed HER2-positive breast cancer were randomly assigned 3:1 to adjuvant T-DM1 for 1 year or paclitaxel plus trastuzumab (TH). Coprimary objectives were to compare the incidence of clinically relevant toxicities between arms and to evaluate invasive disease-free survival (iDFS) with T-DM1. Correlative analyses included the HER2DX genomic tool, multiomic evaluations of HER2 heterogeneity, and predictors of thrombocytopenia. RESULTS After a median follow-up of 5.8 years, 11 iDFS events were observed in the T-DM1 arm, consistent with a 5-year iDFS of 97.0% (95% CI, 95.2 to 98.7). At 5 years, the recurrence-free interval (RFI) was 98.3% (95% CI, 97.0 to 99.7), the overall survival was 97.8% (95% CI, 96.3 to 99.3), and the breast cancer-specific survival was 99.4% (95% CI, 98.6 to 100). Comparable iDFS was observed with T-DM1 irrespective of tumor size, hormone receptor status, centrally determined HER2 immunohistochemical score, and receipt of T-DM1 for more or less than 6 months. Although ATEMPT was not powered for this end point, the 5-year iDFS in the TH arm was 91.1%. Among patients with sufficient tissue for HER2DX testing (n = 187), 5-year outcomes significantly differed according to HER2DX risk score, with better RFI (98.1% v 81.8%, hazard ratio [HR], 0.10, P = .01) and iDFS (96.3% v 81.8%, HR, 0.20, P = .047) among patients with HER2DX low-risk versus high-risk tumors, respectively. CONCLUSION Adjuvant T-DM1 for 1 year leads to outstanding long-term outcomes for patients with stage I HER2-positive breast cancer. A high HER2DX risk score predicted a higher risk of recurrence in ATEMPT.

Abstract Fibrolamellar hepatocellular carcinoma (FLC) is a rare liver cancer that is driven by the fusion of DNAJB1 and PRKACA, the catalytic subunit of protein kinase A (PKA). PKA activity is controlled through regulatory proteins that both inhibit catalytic activity and control localization, and an excess of regulatory subunits ensures PRKACA activity is inhibited. Here, we found an increase in the ratio of catalytic to regulatory units in FLC patient tumors driven by DNAJB1::PRKACA using mass spectrometry, biochemistry, and immunofluorescence, with increased nuclear localization of the kinase. Overexpression of DNAJB1::PRKACA, ATP1B1::PRKACA, or PRKACA, but not catalytically inactive kinase, caused similar transcriptomic changes in primary human hepatocytes, recapitulating the changes observed in FLC. Consistently, tumors in patients missing a regulatory subunit or harboring an ATP1B1::PRKACA fusion were indistinguishable from FLC based on the histopathological, transcriptomic, and drug–response profiles. Together, these findings indicate that the DNAJB1 domain of DNAJB1::PRKACA is not required for FLC. Instead, changes in PKA activity and localization determine the FLC phenotype. Significance: Alterations leading to unconstrained protein kinase A signaling, regardless of the presence or absence of PRKACA fusions, drive the phenotypes of fibrolamellar hepatocellular carcinoma, reshaping understanding of the pathogenesis of this rare liver cancer.

Abstract Background: The ATEMPT trial primary analysis found that one year of adjuvant trastuzumab emtansine (T-DM1) achieved a 3-year iDFS of 97.8% for patients with stage I HER2+ breast cancer, but was not associated with fewer clinically relevant toxicities (CRTs) compared with paclitaxel and trastuzumab (TH). In this end-of-study analysis, we report 5-year survival outcomes and correlative analyses from the trial. Methods: Patients with stage I centrally confirmed HER2+ breast cancer were randomly assigned 3:1 to adjuvant T-DM1 for one year or TH and received T-DM1 3.6 mg/kg IV every 3 weeks for 17 cycles or paclitaxel 80 mg/m2 IV with weekly trastuzumab IV followed by trastuzumab for 9 months. The co-primary objectives were to compare the incidence of CRTs between the 2 arms and to evaluate iDFS in patients receiving T-DM1. To investigate proteomic correlates of recurrence, spatial proteomic analyses were performed on samples from 13 patients experiencing iDFS events (cases) and 24 matched controls using the NanoString GeoMx Digital Spatial Profiler. The impact of HER2 heterogeneity on outcomes was investigated among 17 cases and 51 matched controls by fluorescence in-situ hybridization (FISH). HER2 genetic heterogeneity was assessed by scrutinizing the whole tumor area and defined as the occurrence of HER2 gene amplification in >5% but < 50% invasive tumor cells. The risk of recurrence was evaluated centrally with the HER2DX genomic assay from 225 primary tumor samples. Germline whole genome sequencing (WGS) was conducted among 55 patients experiencing T-DM1-induced thrombocytopenia and/or bleeding and 55 matched controls to identify genomic correlates for this side effect. Results: A total of 497 patients who initiated protocol therapy were included in this analysis (383 T-DM1 and 114 TH). After a median follow up 5.8 years, among patients receiving T-DM1 there were a total of 11 iDFS events, with 3 distant recurrences. The 5-year iDFS for T-DM1 was 97.0% (95% CI, 95.3-98.8%), the 5-year recurrence-free interval (RFI) was 98.6% (95% CI: 97.4-99.8%) and the 5-year overall survival (OS) for T-DM1 was 97.8 % (95% CI, 96.3-99.3%). Although the study was not powered to evaluate the efficacy of TH, among the 114 patients receiving TH, a total of 9 iDFS events were observed, including 2 distant events; the 5-year iDFS with TH was 91.3% (95% CI: 86.0-96.9%), 5-year RFI was 93.3% (95% CI: 88.6-98.2%) and 5-year OS was 97.9% (95% CI: 95.2-100%). A total of 56 samples were evaluable for heterogeneity analyses, among which 14% (n=8) harbored HER2 genetic heterogeneity. Spatial proteomic analyses found that NF1 (adjusted p=0.72 × 10-6) and CTLA-4 (adjusted p=0.15 × 10-3) were significantly upregulated in primary samples from cases, while cleaved caspase 9, CD25, GITR, ICOS, p53 and PD-L2 were significantly upregulated in controls (all with adjusted p< 0.05). Germline WGS found that the top gene associations with thrombocytopenia and thrombocytopenia or bleeding were ALMS1 (p=0,19 × 10-3) and APBA3 (p=0,23 × 10-3), respectively, although none reaching the threshold for genome wide significance. rs62143195 and rs114169776 were the top single nucleotide polymorphisms associated with thrombocytopenia and thrombocytopenia or bleeding, respectively. Data on the impact of HER2 heterogeneity and of HER2DX score on survival outcomes will be presented. Conclusion: With longer follow-up, adjuvant T-DM1 confirmed outstanding long-term outcomes among patients with stage I HER2+ breast cancer, demonstrating a 5-year RFI of 98.6%. Spatial proteomic analyses identified a potential association between NF1 and CTLA-4 expression with recurrence. Details on the impact of HER2 heterogeneity and HER2DX assay on prognosis will be presented. Citation Format: Paolo Tarantino, Nabihah Tayob, Chau T Dang, Denise Yardley, Steven J. Isakoff, Vicente Valero, Meredith Faggen, Therese Mulvey, Ron Bose, Douglas Weckstein, Antonio C. Wolff, Katherine Reeder-Hayes, Hope Rugo, Bhuvaneswari Ramaswamy, Dan Zuckerman, Lowell Hart, Vijayakrishna K. Gadi, Michael Constantine, Kit Cheng, Audrey Merrill Garrett, Paul K. Marcom, Kathy S. Albain, Patricia DeFusco, Nadine Tung, Blair Ardman, Rita Nanda, Rachel C. Jankowitz, Mothaffar Rimawi, Vandana Abramson, Paula R. Pohlmann, Catherine Van Poznak, Andres Forero-Torres, Minetta C. Liu, Kathryn Ruddy, Yue Zheng, Romualdo Barroso-Sousa, Adrienne Waks, Michelle K. DeMeo, Molly K. DiLullo, Giuseppe Curigliano, Harold Burstein, Ann Partridge, Eric Winer, Giuseppe Viale, Winnie Hui, Elizabeth A. Mittendorf, Bryan P. Schneider, Aleix Prat, Ian Krop, Sara Tolaney. Adjuvant Trastuzumab Emtansine Versus Paclitaxel plus Trastuzumab for Stage I HER2+ Breast Cancer: 5-year results and correlative analyses from ATEMPT (TBCRC033) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD18-01.

Abstract To repurpose therapeutics for fibrolamellar carcinoma (FLC), we developed and validated patient-derived xenografts (PDX) from surgical resections. Most agents used clinically and inhibitors of oncogenes overexpressed in FLC showed little efficacy on PDX. A high-throughput functional drug screen found primary and metastatic FLC were vulnerable to clinically available inhibitors of TOPO1 and HDAC and to napabucasin. Napabucasin's efficacy was mediated through reactive oxygen species and inhibition of translation initiation, and specific inhibition of eIF4A was effective. The sensitivity of each PDX line inversely correlated with expression of the antiapoptotic protein Bcl-xL, and inhibition of Bcl-xL synergized with other drugs. Screening directly on cells dissociated from patient resections validated these results. This demonstrates that a direct functional screen on patient tumors provides therapeutically informative data within a clinically useful time frame. Identifying these novel therapeutic targets and combination therapies is an urgent need, as effective therapeutics for FLC are currently unavailable. Significance: Therapeutics informed by genomics have not yielded effective therapies for FLC. A functional screen identified TOPO1, HDAC inhibitors, and napabucasin as efficacious and synergistic with inhibition of Bcl-xL. Validation on cells dissociated directly from patient tumors demonstrates the ability for functional precision medicine in a solid tumor. This article is highlighted in the In This Issue feature, p. 2355

PURPOSE The ATEMPT trial was designed to determine if treatment with trastuzumab emtansine (T-DM1) caused less toxicity than paclitaxel plus trastuzumab (TH) and yielded clinically acceptable invasive disease-free survival (iDFS) among patients with stage I human epidermal growth factor receptor 2–positive (HER2+) breast cancer (BC). METHODS Patients with stage I centrally confirmed HER2+ BC were randomly assigned 3:1 to T-DM1 or TH and received T-DM1 3.6 mg/kg IV every 3 weeks for 17 cycles or T 80 mg/m 2 IV with H once every week × 12 weeks (4 mg/kg load →2 mg/kg), followed by H × 39 weeks (6 mg/kg once every 3 weeks). The co-primary objectives were to compare the incidence of clinically relevant toxicities (CRTs) in patients treated with T-DM1 versus TH and to evaluate iDFS in patients receiving T-DM1. RESULTS The analysis population includes all 497 patients who initiated protocol therapy (383 T-DM1 and 114 TH). CRTs were experienced by 46% of patients on T-DM1 and 47% of patients on TH ( P = .83). The 3-year iDFS for T-DM1 was 97.8% (95% CI, 96.3 to 99.3), which rejected the null hypothesis ( P < .0001). Serially collected patient-reported outcomes indicated that patients treated with T-DM1 had less neuropathy and alopecia and better work productivity compared with patients on TH. CONCLUSION Among patients with stage I HER2+ BC, one year of adjuvant T-DM1 was associated with excellent 3-year iDFS, but was not associated with fewer CRT compared with TH.