Citations

Mayo Clinic

Clear

4508 citation(s) found for "Oh, Scott".

The Association of Microplastics in Peripheral Blood and Pulmonary Disease: A Pilot Study
Helgeson, Scott A. , Alaws, Hossny, Ibrahim, Mohamed I. , Lee, Augustine S., Vlecken, Danielle H. W. , Baig, Hassan , Lee, Augustine S. , Lee, Augustine S , Baig, Hassan Z , Helgeson, Scott A , Vlecken, Danielle H. W.

Journal of Xenobiotics | April 29, 2026 | Volume: 16 | Issue: 3 | Pages: 72

10.3390/jox16030072 | PMID 42201067 Get It

Microplastics may pose health risks, particularly for chronic lung diseases. Clarifying the link between circulating microplastics and pulmonary disease is vital for shaping research and interventions. The objective of this study was to evaluate whether microplastics in peripheral blood are associated with COPD or IPF vs. no lung disease. In this pilot prospective case-control study, participants were grouped as control (n = 10), COPD (n = 9), or IPF (n = 10). Relevant comorbidities and exposures were obtained from records and questionnaires. All underwent standardized blood collection (PlasticTox©). Samples were analyzed for total microplastic concentration, stratified by size (<10 µm, 10–30 µm, 30–70 µm). The primary outcome was to show a difference in total microplastic burden between lung disease and controls. Secondary measures were to determine size-specific concentrations and associations with demographic variables and smoking history. Among 29 participants (median age 70 (IQR 64–80); 14 women (48.3%)), COPD/IPF groups had significantly higher total microplastic concentrations vs. controls (median 26.0 vs. 3.5 particles/100 µL; p < 0.01). Particle burdens <10 µm and 10–30 µm were particularly elevated (both p < 0.01). After adjusting for smoking, only the <10 µm fraction remained independently associated with lung disease (adjusted odds ratio 1.94 (95% CI, 1.23–7.04)). In this pilot exploratory study, individuals with COPD or IPF showed greater circulating microplastic levels than controls. These findings should be interpreted as hypothesis-generating, and larger analytically validated studies are needed to clarify directionality, causal mechanisms, contamination control, and the clinical relevance of circulating microplastic burden.
Assessment of Duration of Sliding Sign in Routine Pelvic Ultrasound Studies
Ojieabu, Christabel , Clingan, Mary J., Caserta, Melanie P. , Clingan, M. Jennings , Young, Scott W. , Patel, Maitray D.

Ultrasound Quarterly | April 27, 2026 | Volume: 42 | Issue: 2 | Pages: No page available

10.1097/ruq.0000000000000739 | PMID 42044514 Get It

This study aims to evaluate the implementation of the uterine sliding sign in routine pelvic ultrasound examinations for improving the diagnosis of deep endometriosis. A retrospective analysis was conducted at Mayo Clinic’s Florida and Arizona campuses, including 200 premenopausal and perimenopausal women with chronic pelvic pain, infertility, or suspected endometriosis. Sonographers performed a uterine sliding maneuver during transvaginal ultrasound, and the acquisition times were recorded. Sonographer experience and the time required to perform the sliding sign were analyzed using Microsoft Excel. The median acquisition time for the uterine sliding sign was 26 seconds, with no statistically significant difference based on sonographer experience. The addition of this maneuver extended the ultrasound examination by <1 minute on average, regardless of sonographer experience level. Incorporating the uterine sliding sign into routine pelvic ultrasound protocols is a quick and efficient method that enhances the detection of deep endometriosis, potentially reducing the significant diagnostic delay associated with endometriosis. This study supports the feasibility and minimal time impact of implementing the Society of Radiologists in Ultrasound (SRU) recommendations for augmented pelvic ultrasound in clinical practice.
Circulating Tumor DNA Assessment of Disease Response in Large B-Cell Lymphoma: Lisocabtagene Maraleucel Versus Autologous Stem Cell Transplantation Standard Therapy
Stepan, Lara , Ansari, Sahar , Abramson, Jeremy, Okal, Abood, Dell’Aringa, Justine, Thompson, Ethan G., Crotta, Alessandro, Chow, Victor A. , Kamdar, Manali , Solomon, Scott R. , Johnston, Patrick B. , Glaß, Bertram , Mutsaers, Pim , Arnason, Jon, Mielke, Stephan , Hernandez-Ilizaliturri, Francisco, Bachanová, Veronika , Chabon, Jacob J. , Alizadeh, Ash A. , Peiser, Leanne, Abramson, Jeremy S. , Abramson, Jeremy S , Shadman, Mazyar , Izutsu, Koji , Bachanova, Veronika , Ibrahimi, Sami , Kurtz, David M , Alizadeh, Ash A , Peiser, Leanne , Kamdar, Manali , Mielke, Stephan , Ansari, Sahar, Arnason, Jon , Shadman, Mazyar , Hernandez‐Ilizaliturri, Francisco J. , Izutsu, Koji , Ibrahimi, Sami , Kurtz, David M.

Journal of Clinical Oncology | April 27, 2026 | Volume: 44 | Issue: 19 | Pages: 1767-1773

10.1200/jco-25-03051 | PMID 42044466 Get It

We report correlative circulating tumor DNA (ctDNA) analyses from TRANSFORM (ClinicalTrials.gov identifier: NCT03575351 ) evaluating lisocabtagene maraleucel (liso-cel) versus standard of care (salvage immunochemotherapy, high-dose chemotherapy, autologous stem cell transplantation [ASCT]) in second-line large B-cell lymphoma (LBCL). ctDNA association with efficacy was investigated at predefined time points (random assignment, day 43, day 64, and day 126 [3 months after liso-cel, approximately 2 months after ASCT]) for 136 patients using ultrasensitive PhasED-Seq. ctDNA clearance (measurable residual disease [MRD] neg ) predicted longer event-free survival (EFS) at all time points in both arms, with significantly more liso-cel–treated patients achieving MRD neg . Liso-cel demonstrated superior outcomes versus ASCT, including longer EFS, progression-free survival (PFS), and duration of response among patients in complete response (CR) and MRD neg . ctDNA re-emergence in patients with CR after ASCT confirmed its potential in predicting relapse. MRD neg remained significantly associated with EFS after adjusting for positron emission tomography (PET) response, while interaction testing revealed a significant interaction between PET status and treatment arm for EFS. Liso-cel achieved deeper, more durable molecular clearance by ctDNA, consistent with superior EFS and PFS versus ASCT for second-line LBCL treatment. ctDNA-MRD provided prognostic value beyond PET, supporting its role as a complementary biomarker for treatment response and relapse prediction.
Machine Learning Models Using Hospital Admission Characteristics Do Not Optimally Predict Nosocomial Infection Development in a Global Cirrhosis Cohort
Silvey, Scott , Choudhury, Ashok , Kamath, Patrick S. , Wong, Florence , Hayes, P C, Seto, Wai‐Kay , Singhal, Garima, Jothimani, Dinesh , Asrani, Sumeet, Gadano, Adrián , Dinçer, Dinc , Adebayo, Daneille, Doyle, Adam, Debzi, Nabil , Shaw, Jawaid , Barutçu, Sezgin , Lah, Ponan Claude Regis, Duarte‐Rojo, Andrés , Turan, Dilara , Wang, Lei, Velazquez, René Malé, Aghayaeva, Sevda, Córdova-Gallardo, J, Xu, Bin, Gao, Haibing , Elangovan, Harendran, Fung, James, Rajorya, Neil, Wang, X I A O Y U, Katchman, Helena , Jiang, Yongfang, Thanapirom, Kessarin , Eapen, CE, Dhiman, Radha K. , Lu, Mingqin, Su, Minghua , Hueso, Sarai Gonzalez, Aberra, Hanna , Fisseha, Henok , Tan, Hiang Keat , Zhao, Caiyan , Zhang, Ningping, MacQuillan, Gerry, Pereira, Gustavo, Reddy, K. Rajender , Topazian, Mark, Torre, A Ullate De La, Silva, Mario, Bush, Brian J., Bajaj, Jasmohan S. , Chaudhary, Ashok , Xie, Qing , Wong, Florence , Arora, Umang , Gadano, Adrian , Dincer, Dinc , Velarde-Ruiz Velasco, José Antonio , Kulkarni, Anand V , Shaw, Jawaid , Desalgn, Hailemicheal , Bettinger, Dominik , Regis Lah, Ponan Claude , Duarte-Rojo, Andres , Turan, Dilara , Zheng, Xin , Demirtas, Coskun , Liu, Chenghai , Cordova-Gallardo, Jacqueline , Nagral, Aabha , Gao, Haibing , Katchmann, Helena , Praharaj, Dibyalochan , Mahadeva, Sanjiv , Eapen, C E , Dhiman, Radha K , Lu, Mingqin , Arrese, Marco , Su, Minghua , Hueso, Sarai Gonzalez , Aberra, Hanna , Fisseha, Henok , Tan, Hiang Keat , Zhao, Caiyan , Zhang, Ningping , Taneja, Sunil , Sonavane, Amey , Saraya, Anoop , Gofton, Cameron , Pereira, Gustavo , Rajender Reddy, K , Sarin, Shiv Kumar , Cao, Zhujun , Topazian, Mark D , Idilman, Ramazan , Torre, Aldo , George, Jacob , BUSH, BRIAN J. , Bajaj, Jasmohan S , Seto, Wai-Kay , Singhal, Garima, Asrani, Sumeet K. , Farias, Alberto Queiróz , Velasco, J.A. Velarde-Ruiz , Kulkarni, Anand V. , Desalegn, Hailemichael , Karasu, Zeki A. , Fung, James , Rajoriya, Neil , Zheng, Katina , Arrese, Marco , Zhu, Chuanwu , Taneja, Sunil , Aravinthan, Aloysious Dominic , MacQuillan, Gerry C., Idılman, Ramazan , George, Jacob , Alvares-da-Silva, Mario Reis

American Journal of Gastroenterology | April 27, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.14309/ajg.0000000000004031 | PMID 42043180 Get It

INTRODUCTION: Nosocomial infections (NIs) in cirrhosis are associated with high mortality but could be preventable. Logistic regression (LR) models have failed to identify high-risk patients. We aimed to develop machine learning (ML) models to predict NI. METHODS: The CLEARED consortium consists of prospectively enrolled cirrhosis inpatients from >120 centers. Using day-of-admission clinical data, 3 ML approaches (random forest [RF], extreme gradient boosting, and neural networks [NNs]) were used to predict NI. Data were split 80:20 for training and testing stratified by the outcome. Models were compared using area under the receiver operating characteristic curve (AUC). RESULTS: In total, 8,263 patients (55.90 ± 13.34 years; 64.1% men) from 127 centers in 37 countries were included. NI developed in 869 (10.5%), a median of 6 (4–11) days of postadmission. Major NIs were respiratory (29.6%) and urinary tract infection (15.7%), and spontaneous bacterial peritonitis (13.5%). NIs occurred more frequently in patients from low/low-middle income countries and those with severe liver disease, alcohol etiology, and admission infections. NIs were associated with inpatient mortality (31.9% vs 8.1%, P < 0.001) and liver transplantation (4.8% vs 1.9%, P < 0.001). Although the RF model (AUC 0.69) showed good calibration (Brier score 0.09), outperforming extreme gradient boosting, neural network, and LR models (AUC 0.66 for all; LR comparison P = 0.043), no model achieved AUC ≥0.80 for clinical utility. At 10% predicted probability threshold, the RF model demonstrated only 75.4% sensitivity, 52.9% specificity, and 15.9% positive predictive value (PPV). DISCUSSION: NIs cannot be accurately predicted from day-of-admission data using ML models, even in a large, prospective, global cirrhosis cohort. Every hospitalized patient with cirrhosis should receive protocolized infection control measures.
Drivers of Labor and Supply Cost Variation in Anterior Cruciate Ligament Reconstruction
Mun, Jeffrey , Dean, Michael C. , Gillinov, Stephen M. , Poutre, Rachel L. , Chenna, Srish S. , Allen, Brandon J. , Treloar, Joshua, Satalich, James R., Martin, Scott D., Mun, Jeffrey S , Treloar, Joshua A , Dean, M. Wingerchuk , Poutre, Rachel L. , Chenna, Srish S. , Etges, Ana Paula Beck da Silva , Satalich, James R. , Martin, Scott D.

Journal of Bone and Joint Surgery | April 23, 2026 | Volume: 108 | Issue: 11 | Pages: 852-859

10.2106/jbjs.25.00667 | PMID 42024715 Get It

Background: Understanding drivers of supply and labor cost variation in orthopaedic surgery is crucial to provide value-based care. Time-driven activity-based costing (TDABC) is a more accurate methodology for capturing costs of care than traditional methods. Anterior cruciate ligament reconstruction (ACLR) is one of the most performed outpatient procedures within orthopaedic surgery. The purpose of this study was to characterize the cost composition of ACLR and identify factors that drive cost variation. Methods: Cost data for supplies and time-based personnel usage were extracted from electronic health records and were used to calculate costs using TDABC. TDABC methodology was applied to calculate the cost of personnel usage by multiplying the duration and associated cost per minute. Descriptive statistics and mixed-effects modeling were used to determine cost drivers. Results: This study included 861 patients who underwent ACLR at 8 hospitals. The mean patient age (and standard deviation) was 31.1 ± 11.6 years. Of the 861 patients, 350 were male and 511 were female; 85.6% of patients were White, 8.1% were Asian, and 3.4% were Black. There was 3.2-fold variation in supply costs ($2,950) and 1.6-fold variation in labor costs ($940) between the 10th and 90th percentiles. Overall, supply costs accounted for 58.2% of total costs, whereas labor costs comprised the remaining 41.8%. The intraoperative phase was the greatest generator of total cost (89.7%). After adjusting for surgeon and hospital variability, variation in total cost was most effectively explained by graft type, primary surgery status, and meniscal repair (conditional R 2 = 0.84; marginal R 2 = 0.27). On subanalysis, patients undergoing allograft ACLR had significantly higher total costs, implant costs, and age compared with those undergoing ACLR with any autograft type (all p < 0.01). Conclusions: The most notable drivers of labor and supply cost variation were graft type, surgeon, surgery center, primary surgery status, and concomitant meniscal repair. Understanding modifiable cost drivers may aid health systems in designing value-based pathways, implant formularies, and surgeon education programs. Future studies may integrate cost with outcome measures for a more holistic view of value. Level of Evidence: Economic and Decision Analysis Level III . See Instructions for Authors for a complete description of levels of evidence.
A Collaborative Best Practice Guide for Promoting AI Vendor Transparency in Health Care — The HAIP AI Vendor Disclosure Framework
Kpodzro, Sena , Hasan, Alifia , Thomas, Ciera , Draugelis, Michael , Jeffries, Scott Morgan , Beecy, Ashley , Stroum, Corinne , Valladares, Alexandra , Eigen, Zev J. , Tobey, Danny , Vidal, David , Mulligan, Deirdre , Balu, Suresh , Kim, Jee Young , Lifson, Mark A. , Sendak, Mark , Kim, Jee Young , Hasan, Alifia , Thomas, Ciera , Draugelis, Michael , Jeffries, Scott Morgan , Beecy, Ashley , Valladares, Alexandra , Tobey, Danny , Vidal, David E , Lifson, Mark A , Balu, Suresh

NEJM AI | April 23, 2026 | Volume: 3 | Issue: 5 | Pages: No page available

10.1056/aip2500985 | PMID 42932684 Get It

Characterizing Neurological Status and Outcomes During Inpatient Rehabilitation in Persons With Nontraumatic Spinal Cord Injury: Early Findings From a Spinal Cord Injury Model Systems Feasibility Study
Shem, Kazuko , Snider, Brittany , Guemez, Ana Valeria Aguirre, Kirshblum, Steven, Sikka, Seema , Reeves, Ronald K. , Engel‐Haber, Einat , Aguirre-Güemez, Ana Valeria, Kirshblum, Steven

Topics in Spinal Cord Injury Rehabilitation | April 22, 2026 | Volume: 32 | Issue: Supplement1 | Pages: 188-199

10.46292/sci25-00122 | PMID 42028352 Get It

Background: The National SCI Model Systems (SCIMS) Database was established in 1973 to study longitudinal data from persons with traumatic SCI (TSCI). The SCIMS provides an ideal platform to explore the feasibility of a parallel data collection effort to understand the characteristics of individuals with nontraumatic SCI (NTSCI). In the current data collection cycle (2021-2026), all SCIMS centers gathered data specific to NTSCI. Objectives: To (1) describe the demographic and injury-specific characteristics of participants with NTSCI and (2) assess neurological changes from admission to discharge. Methods: The International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) examination data of participants with NTSCI who were enrolled at an SCIMS center were extracted from the medical records at admission and discharge from inpatient rehabilitation. Data from 178 participants with NTSCI were analyzed. Results: Among the 93 participants who had adequate ISNCSCI data on admission, only 8.6% had neurological complete injuries. More participants had paraplegia ( n = 58, 62.4%) than tetraplegia ( n = 35, 37.6%). For participants with full ISNCSCI data at both admission and discharge ( n = 47), there were significant improvements in the lower extremity motor score and pinprick and light touch scores on discharge. Conclusion: On admission to acute rehabilitation, more people with NTSCI had paraplegia than tetraplegia, and neurological incomplete injuries were more common. People with NTSCI experienced significant improvement in ISNCSCI neurological variables by the time of discharge from rehabilitation.
Atezolizumab for Alveolar Soft Part Sarcoma: A Clinical Trial Update
Chen, Alice P. , Rosenberger, Christina L. , Moore, Nancy, Foster, Jared C. , Naqash, Abdul Rafeh , Sharon, Elad , Coyne, Geraldine O’Sullivan , Schwartz, Gary K. , Riedel, Richard F. , Glod, John, Hu, James , Read, William L., Merriam, Priscilla , Deshpande, Hari A., Ladle, Brian H. , Okuno, Scott H. , Beck, Jill C., Chen, J Y, Ferry‐Galow, Katherine V., Fino, Kristin, Wilsker, Deborah, Begum, Asma , Parchment, Ralph E. , Doroshow, James H. , O'Sullivan Coyne, Geraldine , Conley, Anthony P , Burgess, Melissa A , Davis, Elizabeth J , Merriam, Priscilla , Ladle, Brian H , Okuno, Scott , Chen, James L , Ferry-Galow, Katherine V , Miller, Brandon L , Wilsker, Deborah F , Doroshow, James H , Riedel, Richard F , Sharon, Elad , Naqash, Abdul Rafeh , Schwartz, Gary K , Moore, Nancy, Glod, John , Conley, Anthony P. , Read, William, Burgess, Melissa , Davis, Elizabeth J. , Deshpande, Hari A.

Journal of Clinical Oncology | April 18, 2026 | Volume: 44 | Issue: 16 | Pages: 1490-1497

10.1200/jco-25-02811 | PMID 41999612 Get It

We previously reported initial results of the pivotal phase II trial of atezolizumab for patients with alveolar soft part sarcoma (ASPS; ClinicalTrials.gov identifier: NCT03141684 ). Here, we report on three additional years of observation. Fifty-three patients with ASPS received atezolizumab. Median duration of response increased to 37.0 months. Objective response rate (ORR) and median progression-free survival (mPFS) remained essentially as previously reported (35.8% [95% CI, 23.1 to 50.2] and 20.8 months [IQR, 7.6-not reached], respectively). ASPSCR1::TFE3 fusion type was determined for 47/53 patients; ORR and mPFS were higher among the 41 patients expressing type 1 (43.9% [95% CI, 28.5 to 60.2] and 28.3 months [IQR, 9.2-not reached], respectively) than the six patients expressing type 2 (0% [95% CI, 0 to 45.9] and 7.5 months [IQR, 3.9-not reached], respectively, PFS HR, 3.2 [95% CI, 1.01 to 10.2]). Eleven patients chose a per-protocol drug holiday (range, 3.5-26.4 months) after ≥2 years of treatment; two experienced disease progression during the holiday. Nine eligible patients elected to receive bevacizumab plus atezolizumab after progressing on monotherapy; ORR was 0% and mPFS was 18.5 months (IQR, 7.9-21.1) in this small cohort. Long-term results support using atezolizumab to treat ASPS, even for several years; a drug holiday with careful monitoring may be an option for some patients.
Fast Antimicrobial Susceptibility Testing for Gram-Negative Bacteremia
Banerjee, Ritu, Komarow, Lauren , Li, Yixuan, Mau, Donald, Geres, Holly, Greenwood-Quaintance, Kerryl, Adler, Amos , Baliga, S, Chrysos, George , Zarkotou, Olympia , Paul, Mical, Regueiro, Dolores Sousa, Chambers, Henry, Fowler, Vance G., Patel, Robin, Group, Antibacterial Resistance Leadership, Chambers, Henry F. , Cross, Heather, Harris, Anthony D. , Duin, David van, Boucher, Helen W., Huntley, Clayton C., Raterman, Erica L., Samuel, Tamika, Moon, Kyung, Holland, Thomas L., Lodise, Thomas, Shelburne, Samuel A. , Cosgrove, Sara E., Lautenbach, Ebbing , Mehigan, Maureen, Doernberg, Sarah B. , Perdue, Sam, Singh, Tara A. , Wickward, Cathy, Souto, David A., Waller, Jason, Evans, Scott R , Banerjee, Ritu , Dodd, Andrew, Geres, Holly, Greenwood‐Quaintance, Kerryl E. , Baliga, Shrikala , Chowers, Michal , Paul, Mical, Pournaras, Spyros , Fowler, Vance G. , Patel, Robin , Evans, Scott , Hamasaki, Toshimitsu , Pettigrew, Melinda M. , Hanson, Kimberly E. , Doi, Yohei , Holland, Thomas L. , Cosgrove, Sara E. , Paterson, David L.

JAMA | April 18, 2026 | Volume: 335 | Issue: 20 | Pages: 1762

10.1001/jama.2026.5487 | PMID 41999287 Get It

Importance Novel blood culture diagnostics provide rapid antimicrobial susceptibility testing (AST) results for bacteria causing bloodstream infections (BSIs) but have unclear clinical impact. Objective To evaluate clinical outcomes of blood culture testing using a rapid AST method compared with standard AST in patients with BSIs caused by gram-negative bacilli in regions with high prevalence of antimicrobial resistance. Design, Setting, and Participants Open-label randomized clinical trial that enrolled participants from December 2023 to May 2025 (final follow-up, June 18, 2025) at 7 medical centers in Greece (n = 2), India (n = 1), Israel (n = 3), and Spain (n = 1). Hospitalized patients (adults and children) with BSIs caused by gram-negative bacilli were eligible. Statistical analysis was conducted from August 2025 to January 2026. Intervention Patients were randomized to undergo blood culture evaluation using rapid, phenotypic AST directly from positive blood cultures plus standard susceptibility testing (n = 413) vs standard susceptibility testing alone (n = 437). Local antimicrobial stewardship teams reviewed all patients and provided treatment recommendations. Main Outcomes and Measures The primary outcome was a desirability of outcome ranking (DOOR) at day 30, with 3 categories (alive without deleterious events, alive with deleterious events, and death). The difference between rapid and standard testing was summarized as the probability that the DOOR outcomes were more desirable in the rapid testing group. Superiority was concluded if the lower limit of the 95% CI exceeded 50%. Secondary outcomes included 30-day mortality, length of hospitalization, intensive care unit admission, acquisition of hospital-acquired infections, time to effective antibiotic therapy within 3 days, and time to antibiotic escalation or deescalation within 3 days. Results Of the 899 patients randomized, 850 were included in the primary outcome analysis (median [IQR] age, 72 [21] years; 43% female). The probability that DOOR outcomes were more favorable in the rapid testing group was 48.8% (95% CI, 45.3%-52.4%). Median time to effective antibiotic therapy was not different between the groups in the as-randomized population. Median time to antibiotic escalation or deescalation was faster in the rapid testing group by 14 hours (95% CI, 6-22) in the as-randomized population. There were no differences between the groups in other secondary outcomes. In the prespecified subgroup with carbapenem-resistant infections, median time to effective therapy was 9.5 hours in the rapid testing group vs 28 hours in the standard testing group (difference, −18 hours [95% CI, −42 to 6]). Conclusions and Relevance Among patients with gram-negative bacilli BSIs, rapid blood culture AST was not superior to standard testing by DOOR. When considered with other efficacy and safety outcomes, these findings may help inform the use of rapid susceptibility testing in clinical practice. Trial Registration ClinicalTrials.gov Identifier: NCT06174649
Abstract LB364: TOP1-DNA protein complex as a predictive biomarker for NKTR-102/Rucaparib combination therapy in PARP-inhibitor resistant ovarian cancer
Venkatachalam, Annapoorna , Nitschmann, Caroline C., Flatten, Karen S., Hurley, Rachel, Hou, Xiaonan, Schenider, Paula A., Goergen, Krista M., Maurer, Matthew, Heinzen, Ethan P. , Oberg, Ann L. , Weroha, S John, Hou, Xiaonan , Correia, Cristina , Haluska, Paul , Kaufmann, Scott H. , Swisher, Elizabeth M.

Cancer Research | April 17, 2026 | Volume: 86 | Issue: 8_Supplement | Pages: LB364-LB364

10.1158/1538-7445.am2026-lb364 Get It

Abstract Despite long-standing interest in combining topoisomerase I (TOP1) poisons with PARP inhibitors (PARPis), the mechanistic basis for the variable and often unpredictable response to this strategy remains unclear. Early preclinical studies suggested that PARP inhibition amplifies TOP1 poison-induced DNA damage, implying broad therapeutic potential; however, emerging translational and clinical data—particularly in ovarian cancer—indicate that synergy is context-dependent and governed by tumor-intrinsic features that have not been fully defined.Here we assessed determinants of response in five HR proficient ovarian cancer (OC) patient-derived xenografts (PDXs) previously treated with the SN-38 prodrug etirinotecan pegol (NKTR-102) in combination with the PARPi rucaparib (C. Nitschmann, Clin. Cancer Res. 22(2) Suppl. B50, 2016). Although all models were refractory to single-agent rucaparib, 50% exhibited enhancement of NKTR-102-induced tumor regression with the addition of rucaparib. Neither PARP1 abundance nor extent of rucaparib-mediated poly(ADP-ribose) suppression correlated with therapeutic benefit. Instead, sensitization was restricted to PDXs intrinsically responsive to NKTR-102 and was strongly associated with high levels of NKTR-102-induced TOP1-DNA covalent complexes. In further analysis, 2 of 3 resistant PDXs exhibited high levels of the ABC transporter ABCG2 despite lack of previous therapy, revealing a previously underappreciated mechanism of de novo resistance that limits effective TOP1 inhibitor activity independent of homologous recombination status. Notably, NKTR-102 response did not track with platinum/taxane sensitivity, highlighting the distinct molecular circuitry governing TOP1 poison susceptibility.Collectively, these findings demonstrate that rucaparib can potentiate NKTR-102-induced regression in tumors capable of forming abundant TOP1-DNA covalent complexes. This work identifies TOP1-DNA complex trapping and lack of ABCG2 expression as mechanistic predictors of benefit, providing an updated framework for selecting patients most likely to respond to TOP1 poison/PARPi combinations and challenging the long-standing assumption that PARP inhibition can universally resensitize tumors to TOP1 poisons. Citation Format: Annapoorna Venkatachalam, Caroline C. Nitschmann, Karen S. Flatten, Rachel Hurley, Xiaonan Hou, Cristina Correia, Paula A. Schenider, Krista Goergen, Matthew Maurer, Ethan P. Heinzen, Ann L. Oberg, S John Weroha, Paul Haluska, Scott H. Kaufmann, Elizabeth M. Swisher. TOP1-DNA protein complex as a predictive biomarker for NKTR-102/Rucaparib combination therapy in PARP-inhibitor resistant ovarian cancer [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 LB364.