Reducing diagnostic delays in acute hepatic porphyria using health records data and machine learning.

BACKGROUND: Acute hepatic porphyria (AHP) is a group of rare but treatable conditions associated with diagnostic delays of 15 years on average. The advent of electronic health records (EHR) data and machine learning (ML) may improve the timely recognition of rare diseases like AHP. However, prediction models can be difficult to train given the limited case numbers, unstructured EHR data, and selection biases intrinsic to healthcare delivery. We sought to train and characterize models for identifying patients with AHP. METHODS: This diagnostic study used structured and notes-based EHR data from 2 centers at the University of California, UCSF (2012-2022) and UCLA (2019-2022). The data were split into 2 cohorts (referral and diagnosis) and used to develop models that predict (1) who will be referred for testing of acute porphyria, among those who presented with abdominal pain (a cardinal symptom of AHP), and (2) who will test positive, among those referred. The referral cohort consisted of 747 patients referred for testing and 99 849 contemporaneous patients who were not. The diagnosis cohort consisted of 72 confirmed AHP cases and 347 patients who tested negative. The case cohort was 81% female and 6-75 years old at the time of diagnosis. Candidate models used a range of architectures. Feature selection was semi-automated and incorporated publicly available data from knowledge graphs. Our primary outcome was the F-score on an outcome-stratified test set. RESULTS: The best center-specific referral models achieved an F-score of 86%-91%. The best diagnosis model achieved an F-score of 92%. To further test our model, we contacted 372 current patients who lack an AHP diagnosis but were predicted by our models as potentially having it (≥10% probability of referral, ≥50% of testing positive). However, we were only able to recruit 10 of these patients for biochemical testing, all of whom were negative. Nonetheless, post hoc evaluations suggested that these models could identify 71% of cases earlier than their diagnosis date, saving 1.2 years. CONCLUSIONS: ML can reduce diagnostic delays in AHP and other rare diseases. Robust recruitment strategies and multicenter coordination will be needed to validate these models before they can be deployed.

Mutational spectrum and genotype-phenotype correlation in Mexican patients with infantile-onset and late-onset Pompe disease.

BACKGROUND: Pompe Disease (PD) is a metabolic myopathy caused by variants in the GAA gene, resulting in deficient enzymatic activity. We aimed to characterize the clinical features and related genetic variants in a series of Mexican patients. METHODS: We performed a retrospective study of clinical records of patients diagnosed with LOPD, IOPD or pseudodeficiency. RESULTS: Twenty-nine patients were included in the study, comprising these three forms. Overall, age of symptom onset was 0.1 to 43 years old. The most frequent variant identified was c.-32-13T>G, which was detected in 14 alleles. Among the 23 different variants identified in the GAA gene, 14 were classified as pathogenic, 5 were likely pathogenic, and 1 was a variant of uncertain significance. Two variants were inherited in cis arrangement and 2 were pseudodeficiency-related benign alleles. We identified two novel variants (c.1615 G>A and c.1076-20_1076-4delAAGTCGGCGTTGGCCTG). CONCLUSION: To the best of our knowledge, this series represent the largest phenotypic and genotypic characterization of patients with PD in Mexico. Patients within our series exhibited a combination of LOPD and IOPD associated variants, which may be related to genetic diversity within Mexican population. Further population-wide studies are required to better characterize the incidence of this disease in Mexican population.

Congenital syndromic Chiari-like malformation (CSCM) in Holstein cattle: towards unravelling of possible genetic causes.

BACKGROUND: Chiari malformation type II (CMII) was originally reported in humans as a rare disorder characterized by the downward herniation of the hindbrain and towering cerebellum. The congenital brain malformation is usually accompanied by spina bifida, a congenital spinal anomaly resulting from incomplete closure of the dorsal aspect of the spinal neural tube, and occasionally by other lesions. A similar disorder has been reported in several animal species, including cattle, particularly as a congenital syndrome. A cause of congenital syndromic Chiari-like malformation (CSCM) in cattle has not been reported to date. We collected a series of 14 CSCM-affected Holstein calves (13 purebred, one Red Danish Dairy F1 cross) and performed whole-genome sequencing (WGS). WGS was performed on 33 cattle, including eight cases with parents (trio-based; group 1), three cases with one parent (group 2), and three single cases (solo-based; group 3). RESULTS: Sequencing-based genome-wide association study of the 13 Holstein calves with CSCM and 166 controls revealed no significantly associated genome region. Assuming a single Holstein breed-specific recessive allele, no region of shared homozygosity was detected suggesting heterogeneity. Subsequent filtering for protein-changing variants that were only homozygous in the genomes of the individual cases allowed the identification of two missense variants affecting different genes, SHC4 in case 4 in group 1 and WDR45B in case 13 in group 3. Furthermore, these two variants were only observed in Holstein cattle when querying WGS data of > 5,100 animals. Alternatively, potential de novo mutational events were assessed in each case. Filtering for heterozygous private protein-changing variants identified one DYNC1H1 frameshift variant as a candidate causal dominant acting allele in case 12 in group 3. Finally, the presence of larger structural DNA variants and chromosomal abnormalities was investigated in all cases. Depth of coverage analysis revealed two different partial monosomies of chromosome 2 segments in cases 1 and 7 in group 1 and a trisomy of chromosome 12 in the WDR45B homozygous case 13 in group 3. CONCLUSIONS: This study presents for the first time a detailed genomic evaluation of CSCM in Holstein cattle and suggests an unexpected genetic and allelic heterogeneity considering the mode of inheritance, as well as the type of variant. For the first time, we propose candidate causal variants that may explain bovine CSCM in a certain proportion of affected calves. We present cattle as a large animal model for human CMII and propose new genes and genomic variants as possible causes for related diseases in both animals and humans.

Connect-ROD - development and qualitative evaluation of a community-based group intervention to support well-being in patients with a rare or orphan disease.

BACKGROUND: Patients living with various rare or orphan diseases (ROD) experience common psychosocial difficulties. Those need emerge from a combination of factors, such as the large variety of patients and the rarity of resources, as well as concentrated efforts on physical health needs that yielded increases in life expectancy and quality in patients. A gap is therefore rising in the consideration of psychosocial needs of patients, such as coping with the impacts of physical limitations, reducing social isolation and distress. To contribute to address this gap, we developed, pilot-tested and evaluated the acceptability, feasibility, implementation, and short-term effects of Connect-ROD, an online group intervention to support adult patients with a ROD (AP-ROD), which aims to improve coping mechanisms, reinforce sense of control, and support personal goals of AP-ROD. A qualitative study comprising of in-depth pretests, post-test interviews and standardized questionnaires, was conducted with 14 participants in two consecutive intervention groups. RESULTS: The Connect-ROD intervention is strongly anchored in acceptance and commitment therapy as well as community psychology approaches. A pilot test allowed us to improve on the initial structure and to produce a manualized 10-week program delivered online, made up of 2-h sessions comprising formal activities, exchanges and homework. The evaluation showed satisfactory acceptability and accessibility, compliant delivery by facilitators, and promising short-term effects on personal objectives, sense of control, coping mechanisms, symptom management, acceptance of the emotions associated with the disease, distress, self-efficacy, social support and connectedness. The program did not show short-term effects on overall quality of life. CONCLUSION: It is recommended that Connect-ROD is evaluated on a larger scale. It seems promising to support various AP-ROD who live with the complex psychosocial consequences of their disease.

Identifying dysregulated regions in amyotrophic lateral sclerosis through chromatin accessibility outliers.

The high heritability of amyotrophic lateral sclerosis (ALS) contrasts with its low molecular diagnosis rate post-genetic testing, pointing to potential undiscovered genetic factors. To aid the exploration of these factors, we introduced EpiOut, an algorithm to identify chromatin accessibility outliers that are regions exhibiting divergent accessibility from the population baseline in a single or few samples. Annotation of accessible regions with histone chromatin immunoprecipitation sequencing and Hi-C indicates that outliers are concentrated in functional loci, especially among promoters interacting with active enhancers. Across different omics levels, outliers are robustly replicated, and chromatin accessibility outliers are reliable predictors of gene expression outliers and aberrant protein levels. When promoter accessibility does not align with gene expression, our results indicate that molecular aberrations are more likely to be linked to post-transcriptional regulation rather than transcriptional regulation. Our findings demonstrate that the outlier detection paradigm can uncover dysregulated regions in rare diseases. EpiOut is available at github.com/uci-cbcl/EpiOut.

A Plasma Pyrophosphate Cutoff Value for Diagnosing Pseudoxanthoma Elasticum.

Pseudoxanthoma elasticum (PXE) is a rare inherited systemic disease responsible for a juvenile peripheral arterial calcification disease. The clinical diagnosis of PXE is only based on a complex multi-organ phenotypic score and/or genetical analysis. Reduced plasma inorganic pyrophosphate concentration [PPi]p has been linked to PXE. In this study, we used a novel and accurate method to measure [PPi]p in one of the largest cohorts of PXE patients, and we reported the valuable contribution of a cutoff value to PXE diagnosis. Plasma samples and clinical records from two French reference centers for PXE (PXE Consultation Center, Angers, and FAVA-MULTI South Competent Center, Nice) were assessed. Plasma PPi were measured in 153 PXE and 46 non-PXE patients. The PPi concentrations in the plasma samples were determined by a new method combining enzymatic and ion chromatography approaches. The best match between the sensitivity and specificity (Youden index) for diagnosing PXE was determined by ROC analysis. [PPi]p were lower in PXE patients (0.92 ± 0.30 µmol/L) than in non-PXE patients (1.61 ± 0.33 µmol/L, p < 0.0001), corresponding to a mean reduction of 43 ± 19% (SD). The PPi cutoff value for diagnosing PXE in all patients was 1.2 µmol/L, with a sensitivity of 83.3% and a specificity of 91.1% (AUC = 0.93), without sex differences. In patients aged <50 years (i.e., the age period for PXE diagnosis), the cutoff PPi was 1.2 µmol/L (sensitivity, specificity, and AUC of 93%, 96%, and 0.97, respectively). The [PPi]p shows high accuracy for diagnosing PXE; thus, quantifying plasma PPi represents the first blood assay for diagnosing PXE.

Pilot Study by Liquid Biopsy in Gastrointestinal Stromal Tumors: Analysis of PDGFRA D842V Mutation and Hypermethylation of SEPT9 Presence by Digital Droplet PCR.

Tissue biopsy remains the standard for diagnosing gastrointestinal stromal tumors (GISTs), although liquid biopsy is emerging as a promising alternative in oncology. In this pilot study, we advocate for droplet digital PCR (ddPCR) to diagnose GIST in tissue samples and explore its potential for early diagnosis via liquid biopsy, focusing on the PDGFRA D842V mutation and SEPT9 hypermethylated gene. We utilized ddPCR to analyze the predominant PDGFRA mutation (D842V) in surgical tissue samples from 15 GIST patients, correlating with pathologists' diagnoses. We expanded our analysis to plasma samples to compare DNA alterations between tumor tissue and plasma, also investigating SEPT9 gene hypermethylation. We successfully detected the PDGFRA D842V mutation in GIST tissues by ddPCR. Despite various protocols to enhance mutation detection in early-stage disease, it remained challenging, likely due to the low concentration of DNA in plasma samples. Additionally, the results of Area Under the Curve (AUC) for the hypermethylated SEPT9 gene, analyzing concentration, ratio, and abundance were 0.74 (95% Confidence Interval (CI): 0.52 to 0.97), 0.77 (95% CI: 0.56 to 0.98), and 0.79 (95% CI: 0.59 to 0.99), respectively. As a rare disease, the early detection of GIST through such biomarkers is particularly crucial, offering significant potential to improve patient outcomes.

Founder mutations and rare disease in the Arab world.

Founder mutations are disease-causing variants that occur frequently in geographically or culturally isolated groups whose shared ancestor(s) carried the pathogenic variant. While some disease alleles may vanish from the genetic pool due to natural selection, variants with weaker effects may survive for a long time, thereby enhancing the prevalence of some rare diseases. These are predominantly autosomal recessive diseases but can also be autosomal dominant traits with late-onset or mild phenotypes. Cultural practices, such as endogamy and consanguinity, in these isolated groups lead to higher prevalence of such rare diseases compared to the rest of the population and worldwide. In this Perspective, we define population isolates and the underlying genetic mechanisms for accumulating founder mutations. We also discuss the current and potential scientific, clinical and public-health implications of studying founder mutations in population isolates around the world, with a particular focus on the Arab population.

Epidemiology and distribution of 207 rare diseases in China: A systematic literature review.

Epidemiological data on rare diseases in China are currently limited. The objective of this study was to provide a comprehensive understanding of the prevalence and incidence of rare diseases by systematically analyzing the available epidemiological data. We conducted a comprehensive search of English and Chinese databases, the Incidence and Prevalence Database, the Chinese Rare Disease Guideline, and the Taiwan Health Promotion Administration from 2010 to 2023. We identified the top diseases and regions based on epidemiological data and present the maximum, minimum, and median prevalence and incidence values in tables and forest plots. 1,264 prevalence and incidence data were retrieved from 277 studies, guidelines and official websites, covering 110 rare diseases (53.1%) and 32 regions (94.1%). In terms of geographical regions, incidence or prevalence data were available for 32 regions (94.1%), excluding Tibet Hui Autonomous Region and Macao Special Administrative Region. In terms of rate, 60 and 77 out of 207 diseases (29.0% and 37.2%) had available incidence and prevalence data, respectively. Eight diseases had an incidence rate equal to or greater than that of 1,000 patients per million. The present study provides a comprehensive epidemiological analysis and valuable insights into the prevalence and incidence of rare diseases in China. Our findings underscore the pressing need for sustained drug research and medical support for individuals and families impacted by rare diseases.

The epidemiology and healthcare burden of rare diseases requiring hospitalisation among adult patients in Langkawi, Malaysia: Insights from a pilot study.

In Malaysia, rare diseases affect fewer than 1 in 4,000 people. As of 2020, 491 rare diseases have been recorded in Malaysia, but with limited epidemiological data. As the first study in Malaysia, this retrospective cohort study examined the epidemiology and admission-related healthcare costs for adult rare disease patients in Langkawi. Among the 38 patients, rheumatological rare diseases topped the list (39.5%). The annual admission rate for rare diseases was 0.9%. Langkawi patients had lengthy hospital stays (9.7 days) and a 7.9% mortality rate. 23.7% of patients defaulted to follow-up, and 7.9% were referred to a tertiary hospital due to inadequate equipment or speciality care. Admission costs were Malaysian Ringgits (MYR) 244,598.63 (~US Dollars (USD) 51,280), with 80.2% from medication. The average healthcare resource utilisation was MYR 6,436.81/ patient/year (~USD 1,350/patient/year).

Functional clinical motor performance tests to assess potential fall risks in patients with haemophilia: A case-control study.

INTRODUCTION: Patients with haemophilia (PwH) are at increased risk of falls due to haemophilic arthropathy. Yet, studies on clinical tests associated with the risk of falling are scarce in PwH. AIMS: (1) To evaluate the feasibility of different clinical motor performance tests associated with the risk of falling in PwH; (2) to evaluate PwH's performance of these tests compared to a control group; (3) to identify possible influencing factors that affect performance. METHODS: Twenty-nine severe and moderate PwH (57.0 years, IQR: 48.0-61.5) and 29 healthy age- and BMI-matched control participants (CG) performed 13 different clinical tests (SPPB, timed up and go, push and release, functional reach, single-leg stance, knee and grip strength). Haemophilia joint health score (HJHS), kinesiophobia (TSK-11), subjective physical performance (HEP-Test-Q), falls efficiency (FES-I) and falls were assessed. RESULTS: No adverse events occurred. PwH showed impaired performance in all clinical tests, a lower falls efficiency and a higher HJHS than CG. PwH with higher HJHS, lower HEP-Test-Q and higher TSK-11 scores showed higher deficits. Largest discrepancies were observed in the single-leg stance with eyes open and knee extensor strength, where orthopaedically majorly affected PwH showed worse performance compared to minorly affected PwH and the CG, respectively. The prevalence of ≥1 fall in the last year was 27.6% (PwH) and 10.3% (CG). CONCLUSION: These clinical tests are feasible in PwH. Impaired joint status, a high kinesiophobia and low physical performance impair performance. These tests can be used by clinicians for gaining specific information on functional motor abilities of patients.

Case report: Sarcomatoid renal cell carcinoma masquerading as hydronephrosis.

Sarcomatoid renal cell carcinoma (SRCC), a manifestation of sarcomatoid dedifferentiation in renal cell carcinoma, is characterized by elevated invasiveness and a grim prognosis. Typically, SRCC patients present with advanced or metastatic conditions and survival rates rarely extend beyond one year. In this study, we describe a case of SRCC characterized by the patient exhibiting right flank pain without hematuria. Initially, imaging interpretations led to a diagnosis of severe hydronephrosis. Subsequently, an open right nephrectomy post-surgery confirmed the pathology of sarcomatoid renal cell carcinoma.

Clinico-Epidemiologic Profile of Non-Syndromic Congenital Ichthyosis - A Retrospective Chart Review of 107 Patients.

Background: Congenital ichthyoses are a rare Mendelian group of disorders affecting the integument with a heterogeneous clinical presentation amongst which scaling is a constant feature. There is scanty epidemiologic data regarding the clinical profile and histologic patterns of inherited ichthyosis from resource-poor countries. Aims and Objectives: The study was aimed at assessing the clinic-epidemiologic characteristics associated with the different forms of non-syndromic congenital ichthyosis. Materials and Methods: This was a retrospective chart review of ichthyosis patients that presented between July 2016 and Jun 2020. Details including demographic profile, clinical characteristics along with any relevant investigations done were included. Results: During the study period of 4 years, 107 patients with congenital non-syndromic ichthyosis were seen. The most frequent diagnosis was of common ichthyoses, followed by autosomal recessive congenital ichthyosis, epidermolytic ichthyosis and erythrokeratoderma, in decreasing order. Conclusion: Important clinical findings like erythema and the type of scales as well as histological differences including an absent or reduced granular layer in ichthyosis vulgaris can help differentiate among the clinical phenotypes of inherited non-syndromic ichthyosis especially in resource-poor settings. Also, there is a high prevalence of vitamin D deficiency and hence a need for screening for the same in all patients of congenital ichthyosis including the milder phenotypes.

Computer-assisted patient identification tool in inborn errors of metabolism - potential for rare disease patient registry and big data analysis.

BACKGROUND: Patient registries are crucial for rare disease management. However, manual registry construction is labor-intensive and often not user-friendly. Our goal is to establish Hong Kong's first computer-assisted patient identification tool for rare diseases, starting with inborn errors of metabolism (IEM). METHODS: Patient data from 2010 to 2019 was retrieved from electronic databases. Through big data analytics, patient data were filtered based on specific IEM-related biochemical and genetic tests. Clinical notes were analyzed using a rule-based natural language processing technique called regular expression. The algorithm classified each extracted paragraph as "IEM-related" or "not IEM-related." Pathologists reviewed the paragraphs for curation, and the algorithm's performance was evaluated. RESULTS: Out of 46,419 patients with IEM-related tests, the algorithm identified 100 as "IEM-related." After pathologists' validation, 96 cases were confirmed as true IEM, with 1 uncertain case and 3 false positives. A secondary ascertainment yielded a sensitivity of 92.3% compared to our previously published IEM cohort. CONCLUSIONS: Our artificial intelligence approach provides a novel method to identify IEM patients, facilitating the creation of a centralized, computer-assisted rare disease patient registry at the local and national levels. This data can potentially be accessed by multiple stakeholders for collaborative research and to enhance healthcare management for rare diseases.

IDeRare: a lightweight and extensible open-source phenotype and exome analysis pipeline for germline rare disease diagnosis.

Objectives: Diagnosing rare diseases is an arduous and challenging process in clinical settings, resulting in the late discovery of novel variants and referral loops. To help clinicians, we built IDeRare pipelines to accelerate phenotype-genotype analysis for patients with suspected rare diseases. Materials and Methods: IDeRare pipeline is separated into phenotype and genotype parts. The phenotype utilizes our handmade Python library, while the genotype part utilizes command line (bash) and Python script to combine bioinformatics executable and Docker image. Results: We described various implementations of IDeRare phenotype and genotype parts with real-world clinical and exome data using IDeRare, accelerating the terminology conversion process and giving insight on the diagnostic pathway based on disease linkage analysis until exome analysis and HTML-based reporting for clinicians. Conclusion: IDeRare is freely available under the BSD-3 license, obtainable via GitHub. The portability of IDeRare pipeline could be easily implemented for semi-technical users and extensible for advanced users.

Current situation of osteogenesis imperfecta in Spain: results from a Delphi study.

BACKGROUND: Osteogenesis imperfecta (OI) is a rare disease characterized by low bone mass and bone fragility, associated with an increased risk of fractures, and skeletal and extra-skeletal symptoms that results in an impairment of health-related quality of life of OI patients. Since published studies on OI in Spain are limited, this study aimed to determine the epidemiology, assessed the disease burden, management and unmet needs of OI patients in Spain. Thirty-four experts in the management of patients with osteogenesis imperfecta completed two rounds of online consultation and reported real-life experience and data from Spanish hospitals. Delphi study questionnaires were based on literature review. A working group of nationally recognized clinical experts supported the development of the study questionnaires and the final validation of results. RESULTS: The estimated prevalence of patients diagnosed with OI in Spain is 0.56:10,000 inhabitants (95%CI: 0.54-0.59), which represents that, approximately, 2,669 OI patients are currently managed in Spanish hospitals. It is estimated that approximately 269 new patients would be diagnosed with OI each year in Spain, representing an estimated incidence of 0.06 (95%CI: 0.05-0.06) per 10,000 inhabitants per year. Clinical management of OI in Spain is performed by a range of medical specialists; however, multidisciplinary care is not fully implemented. The absence of an approved curative treatment or a treatment to reduce the clinical features of the disease remains the main unmet need. CONCLUSIONS: This study provides a snapshot of the current situation of patients with OI in Spain reported by clinical experts. The results provide an estimation of the epidemiology of the disease, and complement the available evidence on disease burden, clinical management, and unmet needs of these patients in Spain.

An 'Adaptive Treatment Strategy' for Oral Vancomycin in Patients with the Orphan Disease Primary Sclerosing Cholangitis.

Decision-making in clinical medicine ideally is based upon evidence from randomized, placebo-controlled trials (RCTs) and subsequent systematic reviews and meta-analyses. However, for orphan diseases, the expectation of having one or multiple RCTs that inform clinical guidelines or justify specific treatments can be unrealistic and subsequent therapeutic nihilism can be detrimental to patients. This article discusses the benefits of therapeutic decision-making in the context of orphan diseases, focusing on primary sclerosing cholangitis (PSC) as an example of an orphan disease with poor clinical outcomes. PSC is a rare disorder characterized by inflammation and progressive fibrosis of the bile ducts. It carries a high risk of liver failure, malignancies, and debilitating symptoms that impair quality of life. Liver transplantation is currently the only life-prolonging intervention for PSC, but it is not a curative option. The article highlights the potential benefits of treating PSC patients with oral vancomycin (OV), which has shown significant clinical responses and improved quality of life in some cases. However, access to OV therapy is limited due to the lack of RCTs supporting its use. The standard requirement of having evidence from RCTs may result in withholding potentially life-altering and/or life-saving treatments for patients with orphan diseases. Conducting RCTs is challenging in these patient populations due to difficulties in recruiting the required patient cohorts and limited commercial returns. A standardized 'adaptive treatment strategy' is proposed to address this. This approach leverages the best available evidence for specific treatments, considers individual clinical responses, and adjusts treatment over time.

International comparison of availability for orphan drugs: focused on approved orphan drugs in South Korea.

Introduction: In this study, we aimed to comparatively analyse the indicators of availability to orphan drugs in South Korea, the United States of America, Europe Union, and Japan. Methods: For 169 drugs designated as orphan drugs in South Korea between 2012 and 2021, information on the drugs designated as orphan drugs from each jurisdiction was extracted by country. Then, the availability indicators (approval time, drug lag time, and designation gap) were analysed for the drugs approved in each jurisdiction. Results: The approval rate of drugs designated as orphan drugs were 11.22% and 6.31% in the USA and EU, respectively, which was lower than that of orphan drugs in South Korea and Japan. The highest number of approved drugs was in the USA (87 drugs), EU 27 drugs, Japan 22 drugs and Korea 21 drugs. Furthermore, the approval time significantly differed between South Korea and the other countries. South Korea had a significantly different drug lag time and designation gap compared with the USA and EU. Conclusion: Our findings show that to fundamentally improve the access to treatments for rare disease, a policy of regulatory science that can comprehensively support the early stages of research and development and commercialisation is needed.

Capturing Patient Voice to Improve Outcomes That Matter to Patients with Desmoid Tumor.

Desmoid tumors (DT) are rare, intermediate-grade sarcomas characterized by locally aggressive growths that commonly occur intra-abdominally, in the abdominal wall, or in the extremities. Desmoid tumors are 2-3-fold more common in females than males, with most patients aged <40 years at diagnosis. Clinical course of DT is highly variable but rarely fatal, with median overall survival >80% at 20 years. However, patient morbidity and DT symptom burden can be high. DT significantly reduce patient quality of life, imposing substantial physical, emotional, and social burdens. Pain, fatigue, and insomnia are common symptoms; disfigurement, mobility restrictions, and, rarely, the need for amputation may also result. Despite its limited impact on survival, patients with DT may have anxiety and depression levels commensurate with those associated with malignant sarcomas. Thus, DT impose an array of significant, long-term morbidities on a young patient population. In order to evaluate the impact of these morbidities, patient-reported outcome (PRO) tools are used, which assess outcomes of importance to patients that extend beyond traditional oncology endpoints. General or oncology-related PROs can be used; although currently, the only DT-specific, validated PRO measure is the GOunder/Desmoid Tumor Research Foundation DEsmoid Symptom/Impact Scale (GODDESS©), consisting of an 11-item DT Symptom Scale (DTSS) and a 17-item DT Impact Scale (DTIS). DTSS and DTIS were secondary endpoints in DeFi, a randomized phase 3 trial of nirogacestat; blinded, pooled data from DeFi were used to validate GODDESS reliability and responsiveness as a PRO measure in DT. Another DT-specific PRO measure, the Desmoid-Type Fibromatosis Quality of Life (DTF-QoL) questionnaire, has been developed but not validated. As novel DT therapies continue to be developed, incorporating DT-specific PRO measures into clinical trials will be key to capturing patient voice, improving outcomes of importance to this unique patient population, and assisting patients and providers in selecting optimal treatment.