A Phase II Basket Trial of Dual Anti-CTLA-4 and Anti-PD-1 Blockade in Rare Tumors (DART SWOG 1609) in Patients with Nonpancreatic Neuroendocrine Tumors.

PurposeImmune checkpoint blockade has improved outcomes across tumor types; little is known about the efficacy of these agents in rare tumors. We report the results of the (nonpancreatic) neuroendocrine neoplasm cohort of SWOG S1609 dual anti-CTLA-4 and anti-PD-1 blockade in rare tumors (DART).Patients and methodsWe performed a prospective, open-label, multicenter phase II clinical trial of ipilimumab plus nivolumab across multiple rare tumor cohorts, with the (nonpancreatic) neuroendocrine cohort reported here. Response assessment by grade was not prespecified. The primary endpoint was overall response rate [ORR; RECIST v1.1; complete response (CR) and partial response (PR)]; secondary endpoints included progression-free survival (PFS), overall survival (OS), stable disease >6 months, and toxicity.ResultsThirty-two eligible patients received therapy; 18 (56%) had high-grade disease. Most common primary sites were gastrointestinal (47%; N = 15) and lung (19%; N = 6). The overall ORR was 25% [95% confidence interval (CI) 13-64%; CR, 3%, N = 1; PR, 22%, N = 7]. Patients with high-grade neuroendocrine carcinoma had an ORR of 44% (8/18 patients) versus 0% in low/intermediate grade tumors (0/14 patients; P = 0.004). The 6-month PFS was 31% (95% CI, 19%-52%); median OS was 11 months (95% CI, 6-∞). The most common toxicities were hypothyroidism (31%), fatigue (28%), and nausea (28%), with alanine aminotransferase elevation (9%) as the most common grade 3/4 immune-related adverse event, and no grade 5 events.ConclusionsIpilimumab plus nivolumab demonstrated a 44% ORR in patients with nonpancreatic high-grade neuroendocrine carcinoma, with 0% ORR in low/intermediate grade disease

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Global, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378–521), affecting 3·40 billion (3·20–3·62) individuals (43·1%, 40·5–45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7–26·7) between 1990 and 2021. Age-standardised rates of deaths per 100 000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6–38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5–32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7–2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed

COVID-19 Outcomes Among Participants in the NHLBI Myelodysplastic Syndromes (MDS) Natural History Study

Abstract Introduction: The NHLBI MDS Natural History Study (NCT02775383) is an ongoing prospective cohort study conducted across 144 sites in the U.S. and Israel intended to establish a data and biospecimen repository to advance the understanding of MDS. In response to the COVID-19 pandemic, the study also collected data on COVID-19 infection and management. Here, we report a summary of COVID-19 outcomes from participants in this study and the impact of the pandemic on study operations. Methods: This prospective cohort study initiated in June, 2016 is enrolling patients (pts) undergoing diagnostic work up for suspected or newly diagnosed MDS or MDS/myeloproliferative neoplasms (MPNs) in the setting of cytopenia. Study enrollment was paused from Mar. 27, 2020 to May 18, 2020 due to COVID-19. Previously untreated pts underwent a bone marrow assessment with a centralized histopathology review at enrollment for assignment to a longitudinal cohort (MDS, MDS/MPN overlap, idiopathic cytopenia of undetermined significance (ICUS), acute myeloid leukemia (AML) with <30% blasts, or "At-Risk" (pts with sub-threshold dysplasia, select karyotype, or select genetic mutations) for follow-up every six months; or a cross-sectional cohort (other cytopenia or cancers) with no further follow-up. COVID-19 outcomes, including tests, status, hospitalizations and treatments for COVID-19, were collected for all eligible pts. Protocol deviations related to COVID-19 were also collected. Fisher's exact test was used for comparing the proportions of pts tested or positive between groups. Results : Of 758 eligible pts with available COVID-19 data, 507 (67%) were assigned to the longitudinal cohort and 251 (33%) to the cross-sectional cohort or are pending assignment. Among longitudinal pts, 74 (15%) had ICUS, 240 (47%) MDS, 47 (9%) MDS/MPN overlap, 11 (2%) AML with <30% blasts, and 135 (27%) At-Risk for MDS. The median age over all pts was 72 years (range=21-95) and 66% were male, 92% White, 4% Black, 2% Asian, and 2% other. Among 244 pts (32%) tested for COVID-19 (Table 1), 23 (9%) were positive. Twelve (>50% of the positive pts) were in Wisconsin, California (CA), and Missouri (Figure 1), with 8 identified from Sep. to Dec. 2020, which overlaps with third waves of COVID-19 reported in CA and in the Midwest. Tests from 17 (74%) of the 23 pts were based on a polymerase chain reaction (PCR) assay. The proportion of pts positive were similar between pooled disease (ICUS, MDS, MDS/MPN, AML <30%), At-Risk, and cross-sectional groups (8%, 8%, 16%, respectively; Table 2) but the proportions tested differed significantly (39%, 28%, and 25%, respectively, p=0.004). Among all positive pts, 21 (91%) are recovering or have recovered (16 with sequelae), 1 (4%) died, and 1 outcome is unknown (Table 1). The one participant who died had MDS with excess blasts-1 (MDS-EB1, 5-9% blasts). Eight pts (35% of positive pts) required hospitalization (median duration of 7 days (range=2-17)) or treatment (tx) in response to COVID-19, 7 of whom required both. In the 8 pts who required tx for COVID-19, 4 reported Remdesivir-use, 3 of whom were diagnosed with MDS or MDS/MPN overlap. The study monthly accrual rates were similar when compared pre- vs. post-study pause (23 vs. 22 pts, respectively) but the rate of missed follow-up visits increased from 5% to 11% post-pause. About half (49%) of the 144 COVID-19-related study deviations occurred during the months the study was paused. Conclusions: In this analysis of 758 pts with MDS and related conditions, the largest reported for these diagnoses, the COVID-19 mortality rate (13%) in MDS was lower than has been reported in a smaller (n=61) case study (39%, Feld et al Blood 2020) but is similar to the rates for MDS observed annually each year prior to study pause (range=11-19%) and to the rate reported in a larger (n=2186) observational study of cancer patients (16%, Rivera et al Cancer Discov 2020). Infection rates were similar across disease groups. The pandemic also resulted in substantial study-specific challenges, including increased rate of deviations, the study being paused, and difficulty sourcing material for biospecimen processing. Data on vaccine efficacy and rates of pts with long-haul symptoms post-COVID may be of interest in future work. Figure 1 Figure 1. Disclosures Padron: BMS: Research Funding; Kura: Research Funding; Taiho: Honoraria; Stemline: Honoraria; Blueprint: Honoraria; Incyte: Research Funding. Komrokji: Novartis: Honoraria; Geron: Honoraria; Acceleron: Honoraria; Agios: Honoraria, Speakers Bureau; Abbvie: Honoraria, Speakers Bureau; JAZZ: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau. Saber: Govt. COI: Other. Al Baghdadi: Bristol-Myers Squibb: Current holder of individual stocks in a privately-held company, Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Current holder of individual stocks in a privately-held company; Epizyme: Current holder of individual stocks in a privately-held company; Heron Therapeutics: Current holder of individual stocks in a privately-held company; Morphosys: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Cardinal Health: Membership on an entity's Board of Directors or advisory committees. DeZern: Taiho: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees. Sekeres: Novartis: Membership on an entity's Board of Directors or advisory committees; Takeda/Millenium: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees

Effect of Selumetinib and MK-2206 vs Oxaliplatin and Fluorouracil in Patients With Metastatic Pancreatic Cancer After Prior Therapy: SWOG S1115 Study Randomized Clinical Trial

ImportanceKRAS mutations are common in pancreatic cancer, but directly targeting the KRAS protein has thus far been unsuccessful. The aim of this trial was to block the MEK and PI3K/AKT pathways downstream of the KRAS protein as an alternate treatment strategy to slow cancer growth and prolong survival. This was the first cooperative group trial to evaluate this strategy using molecularly targeted oral combination therapy for the treatment of chemotherapy-refractory pancreatic cancer.ObjectiveTo compare selumetinib and MK-2206 vs modified FOLFOX (mFOLFOX) in patients with metastatic pancreatic cancer for whom gemcitabine-based therapy had failed.Design, setting, and participantsSWOG S1115 was a randomized phase 2 clinical trial. Between September 2012 and May 2014, 137 patients with metastatic pancreatic adenocarcinoma for whom gemcitabine-based chemotherapy had failed were randomized to selumetinib plus MK-2206 or mFOLFOX. Patients were randomized in a 1:1 fashion and stratified according to duration of prior systemic therapy and presence of liver metastases.InterventionsPatients received selumetinib 100 mg orally per day plus MK-2206 135 mg orally once per week or mFOLFOX (oxaliplatin, 85 mg/m2 intravenous, and fluorouracil, 2400 mg/m2 intravenous infusion over 46-48 hours) on days 1 and 15 of a 28-day cycle.Main outcomes and measuresThe primary end point of the study was overall survival. Secondary objectives included evaluating toxic effects, objective tumor response, and progression-free survival.ResultsThere were 58 patients in the selumetinib plus MK-2206 (experimental) arm (60% male; median [range] age, 69 [54-88] years) and 62 patients in the mFOLFOX arm (35% male; median [range] age, 65 [34-82] years). In the experimental arm, median overall survival was shorter (3.9 vs 6.7 months; HR, 1.37; 95% CI, 0.90-2.08; P = .15), as was median progression-free survival (1.9 vs 2.0 months; HR, 1.61; 95% CI, 1.07-2.43; P = .02). One vs 5 patients had a partial response and 12 vs 14 patients had stable disease in the experimental arm vs mFOLFOX arm. Grade 3 or higher toxic effects were observed in 39 patients treated with selumetinib and MK-2206 vs 23 patients treated with mFOLFOX. More patients in the experimental arm discontinued therapy due to adverse events (13 vs 7 patients).Conclusions and relevanceDual targeting of the MEK and PI3K/AKT pathways downstream of KRAS by selumetinib plus MK-2206 did not improve overall survival in patients with metastatic pancreatic adenocarcinoma for whom gemcitabine-based chemotherapy had failed. This was the first randomized prospective evaluation of mFOLFOX in the US population that showed comparable results to CONKO-003 and PANCREOX.Trial registrationclinicaltrials.gov Identifier: NCT01658943

Diagnosis of Myelodysplastic Syndromes and Related Conditions: Rates of Discordance between Local and Central Review in the NHLBI MDS Natural History Study

Abstract Background Myelodysplastic syndromes (MDS) are a collection of hematopoietic disorders with widely variable prognoses and treatment options. Pathologic diagnosis can be challenging and misdiagnosis can impact patient therapy and outcome. How commonly misdiagnosis occurs, and the severity of diagnostic errors, is not known. Here, we report interim analyses of patients (pts) with cytopenia and suspected MDS from the NHLBI National MDS Natural History Study (https://thenationalmdsstudy.net ClinicalTrials.gov: NCT02775383) assessing MDS occurrence and rates of agreement on classification of MDS/MDS-related disorders by local and centralized review. Methods Pts with cytopenias and clinically suspected MDS were identified between 6/16 and 6/18 from 84 participating centers in this ongoing multi-Institutional Cooperative Group study, with a goal of recruiting 2000 MDS (WHO 2016 subcategories), MDS/MPN or low blast count acute myeloid leukemia (AML, <30% blasts without core binding factor) and 500 cases with idiopathic cytopenia of undetermined significance (ICUS) from both NCI community oncology research program (NCORP) and lead academic participating sites. Centrally submitted clinical and pathologic data and bone marrow samples were analyzed by pathologists in the central laboratory & biorepository (CL/B) blinded to the original site's diagnosis, with a third-level review for cases with disagreement between the local and CL/B assignment. Disagreements in the 5 categories detailed in Figure 1 were considered clinically meaningful. Cases were assigned to longitudinal (MDS, MDS/MPN, ICUS, low blast count AML) versus cross-sectional (other cytopenias or cancers) cohorts after central classification based on clinical, pathologic, and cytogenetic features. Interrater-agreement was evaluated with the Kappa statistic. Results Of 375 pts for whom data and samples were submitted with completed classification, 88 (23%) had MDS, 15 (4%) MDS/MPN, 12 (3%) ICUS, 23 (8%) AML, and 237 (63%) other cytopenias (Figure 1). The median age of all pts was 71 years (range, 20-92), 44% were female, and median baseline blood counts and other baseline measures are in Figure 2. MDS pts had single lineage dysplasia (SLD, 0), SLD with ring sideroblasts (RS, 9 (10%)), multi-lineage dysplasia (MLD, 17 (19%)), MLD -RS (18 (20%)), excess blasts I (EB, 14 (16%)), EBII (19 (22%)), del(5q) (6 (7%)), and MDS-U (5(6%)). IPSS-R categories were defined in 51 of 88 MDS cases (58%): Very Low (27%), Low (43%), Intermediate (27%), High (16%), and Very High (14%). Overall site/central agreement on diagnosis occurred in 225 cases (60%) with inconsistency associated with recognized site coding errors resolved in 54 cases (14%) without 3rd party review. Seventy-eight others (21%) were referred to 3rd level review; confirmation of CL/B classification occurred in 49/78 cases (63%), agreement with site in 13/78 (17%), and a different diagnosis in 16/78 (21%). Clinically meaningful changes in diagnoses between local and central review occurred 26% of the time (Figure 1, n=97/375 kappa =.53 95% CI (.45, .61)). Site assigned MDS was changed to ICUS or other cytopenia in 35% (n=34/99); and to AML in 3% (n=3/99). For cases with site assignment to other causes of cytopenias (225 of 375 cases, 60%), central assignment identified ICUS in 3, MDS/MPN overlap in 8, AML in 2 and MDS in 22, totaling a change in diagnosis in 16%. Of note, 60% (15/25) of ICUS diagnosed locally were interpreted as reactive marrow or normal according to central review. Within MDS cases diagnosed locally, the greatest discrepancy was observed in the MDS-U classification, reported 31 times (31/99 31%) but confirmed in only 2 cases (6%), with 22 (71%) found to not have MDS. Across the study when compared to local assignment, central review changed the follow-up cohort assignment for 87 pts (23%). Conclusions In this well-characterized series of pts evaluated for MDS with bone marrow biopsy and paired site/central morphologic assessment, 40% of site diagnoses were changed at central review and site coding errors were common. In 26%, the changes were clinically meaningful, potentially affecting patient treatment and prognosis. In particular, site designation of MDS-U was an unreliable classification category, which could only partially be attributed to miscoding errors at the local site. Incorporating genomics data might help refine MDS diagnoses. Disclosures Bejar: Genoptix: Consultancy; Takeda: Research Funding; Celgene: Consultancy, Honoraria; Modus Outcomes: Consultancy; Astex/Otsuka: Consultancy, Honoraria; AbbVie/Genentech: Consultancy, Honoraria; Foundation Medicine: Consultancy. Komrokji:Novartis: Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Celgene: Honoraria, Research Funding; Novartis: Honoraria, Speakers Bureau; Celgene: Honoraria, Research Funding; Novartis: Honoraria, Speakers Bureau. Scott:Agios: Consultancy; Novartis: Research Funding; Celgene: Consultancy, Research Funding; Alexion: Consultancy. Gore:Celgene: Consultancy, Research Funding. Sekeres:Opsona: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Opsona: Membership on an entity's Board of Directors or advisory committees

Discordant pathologic diagnoses of myelodysplastic neoplasms and their implications for registries and therapies.

Myelodysplastic neoplasms (MDS) are a collection of hematopoietic disorders with widely variable prognoses and treatment options. Accurate pathologic diagnoses present challenges because of interobserver variability in interpreting morphology and quantifying dysplasia. We compared local clinical site diagnoses with central, adjudicated review from 918 participants enrolled in the ongoing National Heart, Lung, and Blood Institute National MDS Natural History Study, a prospective observational cohort study of participants with suspected MDS or MDS/myeloproliferative neoplasms (MPNs). Locally, 264 (29%) were diagnosed as having MDS, 15 (2%) MDS/MPN overlap, 62 (7%) idiopathic cytopenia of undetermined significance (ICUS), 0 (0%) acute myeloid leukemia (AML) with &lt;30% blasts, and 577 (63%) as other. Approximately one-third of cases were reclassified after central review, with 266 (29%) diagnosed as MDS, 45 (5%) MDS/MPN overlap, 49 (5%) ICUS, 15 (2%) AML with &lt;30%, and 543 (59%) as other. Site miscoding errors accounted for more than half (53%) of the local misdiagnoses, leaving a true misdiagnosis rate of 15% overall, 21% for MDS. Therapies were reported in 37% of patients, including 43% of patients with MDS, 49% of patients with MDS/MPN, and 86% of patients with AML with &lt;30% blasts. Treatment rates were lower (25%) in cases with true discordance in diagnosis compared with those for whom local and central diagnoses agreed (40%), and receipt of inappropriate therapy occurred in 7% of misdiagnosed cases. Discordant diagnoses were frequent, which has implications for the accuracy of study-related and national registries and can lead to inappropriate therapy. This trial was registered at www.clinicaltrials.gov as #NCT05074550

Discordant pathologic diagnoses of myelodysplastic neoplasms and their implications for registries and therapies

Myelodysplastic neoplasms (MDS) are a collection of hematopoietic disorders with widely variable prognoses and treatment options. Accurate pathologic diagnoses present challenges because of interobserver variability in interpreting morphology and quantifying dysplasia. We compared local clinical site diagnoses with central, adjudicated review from 918 participants enrolled in the ongoing National Heart, Lung, and Blood Institute National MDS Natural History Study, a prospective observational cohort study of participants with suspected MDS or MDS/myeloproliferative neoplasms (MPNs). Locally, 264 (29%) were diagnosed as having MDS, 15 (2%) MDS/MPN overlap, 62 (7%) idiopathic cytopenia of undetermined significance (ICUS), 0 (0%) acute myeloid leukemia (AML) with <30% blasts, and 577 (63%) as other. Approximately one-third of cases were reclassified after central review, with 266 (29%) diagnosed as MDS, 45 (5%) MDS/MPN overlap, 49 (5%) ICUS, 15 (2%) AML with <30%, and 543 (59%) as other. Site miscoding errors accounted for more than half (53%) of the local misdiagnoses, leaving a true misdiagnosis rate of 15% overall, 21% for MDS. Therapies were reported in 37% of patients, including 43% of patients with MDS, 49% of patients with MDS/MPN, and 86% of patients with AML with <30% blasts. Treatment rates were lower (25%) in cases with true discordance in diagnosis compared with those for whom local and central diagnoses agreed (40%), and receipt of inappropriate therapy occurred in 7% of misdiagnosed cases. Discordant diagnoses were frequent, which has implications for the accuracy of study-related and national registries and can lead to inappropriate therapy. This trial was registered at www.clinicaltrials.gov as #NCT05074550