Drug Discov Today. 2025 Apr;30(4):104346. doi: 10.1016/j.drudis.2025.104346. Epub 2025 Mar 28.

ABSTRACT

Ultra-rare diseases, particularly those that affect a few hundred patients worldwide, are of little commercial interest to the pharmaceutical industry. Patient-led organizations have made remarkable progress in funding the early-stage, academic development of therapies for such neglected ultra-rare conditions. But the long and difficult path to translate most academic proof-of-concept studies into approved medicines means that very few therapies ever reach patients. Here, we discuss some of the roadblocks to the development of therapeutics for conditions of limited commercial interest and propose ways to overcome these obstacles.

PMID:40158837 | DOI:10.1016/j.drudis.2025.104346

Echocardiography. 2025 Apr;42(4):e70142. doi: 10.1111/echo.70142.

ABSTRACT

Left main coronary artery atresia (LMCAA) is a rare congenital coronary anomaly and sometimes presents with non-specific clinical symptoms that make the diagnosis challenging. We are presenting an interesting case that required multimodality imaging to establish the diagnosis.

PMID:40159450 | DOI:10.1111/echo.70142

Bull Cancer. 2025 Mar;112(3S1):3S107-3S116. doi: 10.1016/S0007-4551(25)00164-X.

ABSTRACT

In Europe, a rare cancer is defined as having an incidence rate of less than 6/100,000. Rare lung cancers encompass many entities defined by the 2021 WHO classification of thoracic tumors, and represent around 10% of all lung cancers. Rare lung cancers involve several histological types (carcinoma, sarcoma and lymphoma), each of which comprises several entities. The management of these patients with rare cancers requires specific medical expertise at every level (diagnosis, treatment and follow-up). These patients should therefore be referred to expert centers affiliated with national networks, giving them appropriate care and better access to innovative treatments. The deployment of systematic molecular characterization of these tumors has allowed for the identification and better characterization of specific entities. Some entities are specific to the lung, while others are more commonly found in other organs. In this review, we will only consider malignant lung tumors with an incidence of less than 1%.

PMID:40155070 | DOI:10.1016/S0007-4551(25)00164-X

PLoS One. 2025 Mar 28;20(3):e0304540. doi: 10.1371/journal.pone.0304540. eCollection 2025.

ABSTRACT

The primary objective is to identify which observational research methods have been used in the last 5 years in rare disease drug evaluation and how they are applied to generate adequate evidence regarding the real-world effectiveness or safety of rare disease drugs. Rare disease is an umbrella term for a condition which affects < 200,000 people each year and despite the rarity of these conditions, collectively they encompass approximately 7000 different conditions. With the striking number of rare conditions, many pharmaceutical manufacturers are introducing an increased number of drugs to treat them. However, due to small patient populations, heterogeneity and other factors related to rare diseases, there are feasibility concerns regarding the generation of adequate efficacy and safety evidence using conventional randomized controlled trials (RCTs). Recently, real-world evidence generated through observational (or real-world) studies has been proposed to address some of the feasibility concerns with RCTs by measuring drug effectiveness or safety in the real-world setting. However, there remain methodological concerns due to a lack of randomization/masking. This proposed scoping review aims to identify which observational research methods in the last 5 years are used in rare disease drug evaluation to address methodological concerns and how they are applied to generate evidence on drug effectiveness or safety. Articles must be primary observational or real-world studies reporting rare disease drug effectiveness or safety published within the five years preceding this review. Literature reviews, meta-analyses, randomized control trials, case series, case reports, opinion pieces, conference abstracts, and studies with unavailable full-text articles will be excluded. The search strategy will combine the following key search concepts: rare disease, drugs for rare disease and observational/real-world studies. The search will be conducted in MEDLINE and EMBASE. Review registration number: Open Science Framework, https://osf.io/f3wpv.

PMID:40153394 | DOI:10.1371/journal.pone.0304540

BMC Cancer. 2025 Mar 28;25(1):558. doi: 10.1186/s12885-025-13934-2.

ABSTRACT

BACKGROUND: Cancers affecting < 6/100,000/year are classified as rare, but they account for up to 25% of all cancers and are associated with worse 5-year survival than common cancers. Early-phase clinical trials (EPCTs) may represent a viable treatment option for patients with rare cancers as they have evolved significantly with novel designs and the increasing use of precision medicine.

METHODS: A retrospective study of patients with rare cancers referred to a large EPCT team at a UK specialist centre over 5 years (2016-2020) was conducted. Patient demographics, medical and oncological history, genomic variants, EPCT participation, responses and survival outcomes were analysed.

RESULTS: In total, 240 patients with rare cancers were included. The mean age at diagnosis was 51.7 years (range 16-84), 54.2% of the patients were female. The most frequent rare cancers originated from the digestive system (27.1%), female genital tract (20%) and head and neck (H + N) (18.3%). Molecular profiling was offered to 45.5% of the population, median number of gene alterations was 3 per patient (range 1-20) while actionable gene alterations were reported in 60.2% (n = 50) of those with identified gene aberrations. Fifty-one patients participated in EPCTs, with 39.2% achieving SD and 11.8% PR. Median PFS for trial participants was three months (95% CI 1.12 - 4.88) while median OS in the trial patients was 16 months (95% CI 9.10 - 22.90) compared to 7 months for non-trial participants (95% CI 5.50 - 8.51). Finally, poor Royal Marsden Hospital (RMH) prognostic score (2-3) was correlated with worse survival when controlling for age and sex (HR 1.714, 95% CI 1.19 - 2.46, p = 0.004).

CONCLUSIONS: Participation of patients with rare cancers in EPCTs may be associated with a survival benefit and lead to the development of new treatments for these patients. Moreover, expanded use of precision medicine is paramount as it can inform targeted treatment selection in this heterogenous group.

PMID:40148757 | DOI:10.1186/s12885-025-13934-2

Genome Res. 2025 Apr 14;35(4):755-768. doi: 10.1101/gr.279414.124.

ABSTRACT

Solve-RD is a pan-European rare disease (RD) research program that aims to identify disease-causing genetic variants in previously undiagnosed RD families. We utilized 10-fold coverage HiFi long-read sequencing (LRS) for detecting causative structural variants (SVs), single-nucleotide variants (SNVs), insertion-deletions (indels), and short tandem repeat (STR) expansions in previously studied RD families without a clear molecular diagnosis. Our cohort includes 293 individuals from 114 genetically undiagnosed RD families selected by European Reference Network (ERN) experts. Of these, 21 families were affected by so-called "unsolvable" syndromes for which genetic causes remain unknown and for which prior testing was not a prerequisite. The remaining 93 families had at least one individual affected by a rare neurological, neuromuscular, or epilepsy disorder without a genetic diagnosis despite extensive prior testing. Clinical interpretation and orthogonal validation of variants in known disease genes yielded 12 novel genetic diagnoses due to de novo and rare inherited SNVs, indels, SVs, and STR expansions. In an additional five families, we identified a candidate disease-causing variant, including an MCF2/FGF13 fusion and a PSMA3 deletion. However, no common genetic cause was identified in any of the "unsolvable" syndromes. Taken together, we found (likely) disease-causing genetic variants in 11.8% of previously unsolved families and additional candidate disease-causing SVs in another 5.4% of these families. In conclusion, our results demonstrate the potential added value of HiFi long-read genome sequencing in undiagnosed rare diseases.

PMID:40138663 | DOI:10.1101/gr.279414.124

Soc Sci Med. 2025 May;372:117958. doi: 10.1016/j.socscimed.2025.117958. Epub 2025 Mar 14.

ABSTRACT

Rare disease organisations can play a crucial role in shaping the medical and scientific landscape. This article draws from interviews with sixteen founders of UK-based, rare disease organisations, all of whom were patients, parents or family members, to understand their experiences and commitment to the organisation and its community. First, we explore the work involved in creating a professional community and addressing the challenge of expert capacity-building for rare diseases. We then utilise the concept of 'translation' to emphasise the efforts of founders at an intermediate stage, for example encouraging health professionals to collaborate and realise that a project is achievable. Third, we consider the personal implications for the founders in their efforts to develop and sustain the organisation. Founders' biographies are intimately entwined with the establishment and development of their organisation, and we highlight how they are fundamentally shaped by the necessity of their hard work, skills and passion. Finally, we recognise that although some of the efforts of founders are undervalued both socially and economically, the founders themselves understand their work and role as crucial to the organisation's long-term success.

PMID:40138978 | DOI:10.1016/j.socscimed.2025.117958

Pediatr Blood Cancer. 2025 Jun;72(6):e31667. doi: 10.1002/pbc.31667. Epub 2025 Mar 25.

ABSTRACT

BACKGROUND: Although research has improved the prognosis of childhood cancer, many challenges remain, especially for high-risk, recurrent, and rare cancers. The recognition that diverse cancer types may share molecular alterations that can be therapeutically targeted has stimulated "precision medicine" approaches in research. Understanding parent and patient interest in genomic-derived therapeutic options in the clinical setting is limited and offers a potential for improved care.

METHODS: A qualitative study was conducted to explore how young adult (YA) patients and parents of children and adolescent patients regard targeted therapy options. These patients had high-risk, recurrent, or rare cancer for which there was no known curative therapy and were enrolled in a study evaluating investigational genomic tumor profiling. Clinical data were retrieved from medical records, and interviews were conducted.

RESULTS: Seventeen participants were interviewed (11 parents and six YA patients). Six themes emerged: (i) Genomic Understanding, (ii) Partnerships in Decision-Making, (iii) Connection with and Trust in Providers, (iv) Quality-of-Life (QOL) Considerations, (v) Understanding of Prognosis, and (vi) Nurturing Hope. Treatment decision-making is complex and depends on the connection (with providers and others), understanding (of prognosis, genomic literacy), care goals (QOL considerations), and planning for the future (hope).

CONCLUSIONS: Participants favored partnership in decision-making, expressed trust in their providers, and recognized the value of research. Engaging parents and YA patients in the planning of precision medicine translational research may be a path to designing an integrated research and care model that maximizes translational research implemented in real time, leading to improved outcomes.

PMID:40130678 | DOI:10.1002/pbc.31667

Proc Natl Acad Sci U S A. 2025 Apr;122(13):e2420343122. doi: 10.1073/pnas.2420343122. Epub 2025 Mar 24.

ABSTRACT

Congenital heart disease (CHD) is a leading cause of infant mortality. We analyzed de novo mutations (DNMs) and very rare transmitted/unphased damaging variants in 248 prespecified genes in 11,555 CHD probands. The results identified 60 genes with a significant burden of heterozygous damaging variants. Variants in these genes accounted for CHD in 10.1% of probands with similar contributions from de novo and transmitted variants in parent-offspring trios that showed incomplete penetrance. DNMs in these genes accounted for 58% of the signal from DNMs. Thirty-three genes were linked to a single CHD subtype while 12 genes were associated with 2 to 4 subtypes. Seven genes were only associated with isolated CHD, while 37 were associated with 1 or more extracardiac abnormalities. Genes selectively expressed in the cardiomyocyte lineage were associated with isolated CHD, while those widely expressed in the brain were also associated with neurodevelopmental delay (NDD). Missense variants introducing or removing cysteines in epidermal growth factor (EGF)-like domains of NOTCH1 were enriched in tetralogy of Fallot and conotruncal defects, unlike the broader CHD spectrum seen with loss of function variants. Transmitted damaging missense variants in MYH6 were enriched in multiple CHD phenotypes and account for ~1% of all probands. Probands with characteristic mutations causing syndromic CHD were frequently not diagnosed clinically, often due to missing cardinal phenotypes. CHD genes that were positively or negatively associated with development of NDD suggest clinical value of genetic testing. These findings expand the understanding of CHD genetics and support the use of molecular diagnostics in CHD.

PMID:40127276 | DOI:10.1073/pnas.2420343122

J Am Podiatr Med Assoc. 2025 Jan-Feb;115(1):23-182. doi: 10.7547/23-182.

ABSTRACT

Osteolipoma is a rare lipoma variant characterized by mature osseus metaplasia within mature adipose tissue, most commonly found in the head and neck, and seldom reported in the extremities. We present a case of a large osteolipoma of the posterior ankle associated with antecedent trauma. These tumors are typically slow growing and can be associated with pain and stiffness, depending on tumor size and location. Treatment is surgical excision, and recurrence is not reported. Interdisciplinary care involving radiology, pathology, and the surgical service is necessary for proper diagnosis and treatment of this rare benign neoplasm.

PMID:40126985 | DOI:10.7547/23-182

J Pediatr Hematol Oncol. 2025 Apr 1;47(3):109-114. doi: 10.1097/MPH.0000000000003008. Epub 2025 Mar 24.

ABSTRACT

BACKGROUND: Congenital CD59 deficiency is a rare genetic disorder marked by chronic hemolysis, recurrent cerebrovascular events, and chronic inflammatory demyelinating polyneuropathy (CIDP). In a specific clinic, 3 siblings from a consanguineously married family were diagnosed with this condition, suggesting a genetic predisposition in their village where endogamous marriages are common.

MATERIALS AND METHODS: Genetic screening was conducted on 71 individuals from the village, including relatives of the diagnosed siblings, to investigate the prevalence and genetic transmission of the disorder.

RESULTS: The screening identified 18 carriers of the genetic mutation and revealed 2 additional siblings of the index patient with the disease. A past case of a cousin with a similar clinical history was also uncovered.

CONCLUSION: The findings highlight the increased risk of genetic disorders like CD59 deficiency in populations with frequent consanguineous marriages. The study underscores the importance of genetic counseling and preventive measures in such communities to mitigate the risk of congenital disorders.

PMID:40126046 | DOI:10.1097/MPH.0000000000003008

Drug Discov Today. 2025 Apr;30(4):104343. doi: 10.1016/j.drudis.2025.104343. Epub 2025 Mar 22.

ABSTRACT

Drug-device combinations (DDCs) are therapeutic products that integrate drugs with medical devices to enhance treatment efficacy and/or safety. These combinations hold significant promise for rare diseases, which affect millions of patients globally, by improving drug delivery, targeting specific organs, and reducing side effects. However, the regulatory framework for DDCs remains complex and lacks specific incentives for rare diseases, unlike orphan drugs. This review examines regulatory approaches and case studies of DDCs in rare diseases, and highlights specific challenges and untapped opportunities. Moreover, the publication discusses recommendations to overcome these challenges through tailored policies and incentives to unlock the potential of DDCs in the context of rare diseases.

PMID:40122448 | DOI:10.1016/j.drudis.2025.104343

Orphanet J Rare Dis. 2025 Mar 22;20(1):141. doi: 10.1186/s13023-025-03619-1.

ABSTRACT

BACKGROUND: Chronic singultus lasting longer than one month is a rare disease. Due to its low prevalence, generating evidence about it is difficult. Patients with chronic diseases struggle with considerable restrictions in their quality of life. Chronic hiccups can lead to problems such as insomnia, anorexia, fatigue, exhaustion, weight loss, and depression. The aim of this study was to gain a better understanding of the quality of life of patients with chronic singultus and their experiences in contact with the healthcare system and with the general population.

METHODS: The data were collected using semi-structured interviews. The data analysis was carried out using qualitative structuring content analysis according to Kuckartz and Rädiker. Reliability was ensured by joint interprofessional evaluation of the interviews by experts, considering different perspectives.

RESULTS: Interviews from 20 patients with chronic singultus were analyzed. Analysis yielded 43 categories that could be assigned to five main topics. The disease burden of the patients was high. In addition to physical symptoms such as concomitant gastroenterological symptoms, shortness of breath, and fatigue, psychosocial consequences such as shame, social withdrawal, anxiety, depression, and even suicidality led to reduced quality of life.

CONCLUSIONS: Ignorance and helplessness among healthcare stakeholders in the case of chronic singultus could lead to a marginalization of the disease and patients. Referring patients to a center with the appropriate expertise can help to avoid underuse, overuse, or misuse of healthcare. Therefore, the awareness of the disease among stakeholders must raise.

PMID:40121512 | DOI:10.1186/s13023-025-03619-1

BMC Bioinformatics. 2025 Mar 22;26(1):87. doi: 10.1186/s12859-025-06105-4.

ABSTRACT

BACKGROUND: Computational approaches to support rare disease diagnosis are challenging to build, requiring the integration of complex data types such as ontologies, gene-to-phenotype associations, and cross-species data into variant and gene prioritisation algorithms (VGPAs). However, the performance of VGPAs has been difficult to measure and is impacted by many factors, for example, ontology structure, annotation completeness or changes to the underlying algorithm. Assertions of the capabilities of VGPAs are often not reproducible, in part because there is no standardised, empirical framework and openly available patient data to assess the efficacy of VGPAs-ultimately hindering the development of effective prioritisation tools.

RESULTS: In this paper, we present our benchmarking tool, PhEval, which aims to provide a standardised and empirical framework to evaluate phenotype-driven VGPAs. The inclusion of standardised test corpora and test corpus generation tools in the PhEval suite of tools allows open benchmarking and comparison of methods on standardised data sets.

CONCLUSIONS: PhEval and the standardised test corpora solve the issues of patient data availability and experimental tooling configuration when benchmarking and comparing rare disease VGPAs. By providing standardised data on patient cohorts from real-world case-reports and controlling the configuration of evaluated VGPAs, PhEval enables transparent, portable, comparable and reproducible benchmarking of VGPAs. As these tools are often a key component of many rare disease diagnostic pipelines, a thorough and standardised method of assessment is essential for improving patient diagnosis and care.

PMID:40121479 | DOI:10.1186/s12859-025-06105-4

Orphanet J Rare Dis. 2025 Mar 20;20(1):138. doi: 10.1186/s13023-025-03633-3.

ABSTRACT

BACKGROUND: Adults with rare disorders experience multiple psychosocial risk factors beyond their medical symptoms, including impaired quality of life, social isolation, loneliness, and mental health problems. These risk factors were amplified during the COVID-19 pandemic, when health care appointments and social/vocational activities were reduced or cancelled. There is a lack of longitudinal data tracking this population over time, making the long term consequences uncertain.

METHODS: We conducted a monthly survey of 58 adults aged between 19 and 71 years (M = 45.1 years, SD = 12.6) with rare disorders across 13 months during the COVID-19 pandemic in Norway. We measured symptoms of anxiety and depression with the Hopkins Symptom Checklist-5. Covid fear was measured with the Coronavirus Anxiety Scale. We examined the mental health and covid fear trajectories across the 13 months with multi-level growth curve models with repeated measures at Level 1 and individuals at Level 2. To account for differences in governmental restrictions throughout the 13 months, we used the stringency index from The Oxford Covid-19 Government Response Tracker.

RESULTS: The growth models indicated stable levels of anxiety and depression over 13 months that were elevated compared to existing population data and were unpredicted by pandemic restrictions. The level of covid fear was significantly associated with the levels of anxious and depressive symptoms.

CONCLUSIONS: The current study found elevated and stable trajectories of mental health symptoms throughout the pandemic for persons with rare disorders. This highlights the necessity of investigating the long-lasting influence of the pandemic on mental health among individuals with rare disorders.

PMID:40114232 | DOI:10.1186/s13023-025-03633-3

Genome Res. 2025 Apr 14;35(4):914-928. doi: 10.1101/gr.279323.124.

ABSTRACT

Rare structural variants (SVs)-insertions, deletions, and complex rearrangements-can cause Mendelian disease, yet they remain difficult to accurately detect and interpret. We sequenced and analyzed Oxford Nanopore Technologies long-read genomes of 68 individuals from the undiagnosed disease network (UDN) with no previously identified diagnostic mutations from short-read sequencing. Using our optimized SV detection pipelines and 571 control long-read genomes, we detected 716 long-read rare (MAF < 0.01) SV alleles per genome on average, achieving a 2.4× increase from short reads. To characterize the functional effects of rare SVs, we assessed their relationship with gene expression from blood or fibroblasts from the same individuals and found that rare SVs overlapping enhancers were enriched (LOR = 0.46) near expression outliers. We also evaluated tandem repeat expansions (TREs) and found 14 rare TREs per genome; notably, these TREs were also enriched near overexpression outliers. To prioritize candidate functional SVs, we developed Watershed-SV, a probabilistic model that integrates expression data with SV-specific genomic annotations, which significantly outperforms baseline models that do not incorporate expression data. Watershed-SV identified a median of eight high-confidence functional SVs per UDN genome. Notably, this included compound heterozygous deletions in FAM177A1 shared by two siblings, which were likely causal for a rare neurodevelopmental disorder. Our observations demonstrate the promise of integrating long-read sequencing with gene expression toward improving the prioritization of functional SVs and TREs in rare disease patients.

PMID:40113264 | DOI:10.1101/gr.279323.124

Curr Opin Oncol. 2025 May 1;37(3):250-258. doi: 10.1097/CCO.0000000000001141. Epub 2025 Mar 19.

ABSTRACT

PURPOSE OF REVIEW: Rare cancers of the genitourinary (GU) tract are often clinically aggressive yet have few or no standard-of-care treatments. Multiple antibody-drug conjugates (ADCs) have been approved in solid malignancies. This review explores the use of ADCs in rare GU tumors in the context of biological pathways and ongoing research in solid tumors.

RECENT FINDINGS: Few clinical trials of ADCs focus on recruiting participants with rare tumors of the GU tract, including trials testing enfortumab vedotin as monotherapy or combined with pembrolizumab, and sacituzumab govitecan as monotherapy or combined with atezolizumab. We highlight many ongoing trials of novel ADCs for advanced/metastatic solid tumors and emphasize the potential eligibility of patients with rare GU tumors for tumor-agnostic trials.

SUMMARY: ADCs are being tested in multiple solid tumors, including rare GU tumors. Ongoing preclinical research supports the use of some ADCs in several rare GU tumors and improves our understanding of their pathophysiology.

PMID:40110990 | DOI:10.1097/CCO.0000000000001141

Zhongguo Dang Dai Er Ke Za Zhi. 2025 Mar 15;27(3):373-376. doi: 10.7499/j.issn.1008-8830.2409076.

ABSTRACT

The patient is a male neonate born at term. He was admitted 16 minutes after birth due to stridor and inspiratory respiratory distress. Physical examination revealed a cleft palate, and a grade II systolic ejection murmur was audible at the left sternal border. Whole exome sequencing identified a heterozygous variant in the SON gene, c.5753-5756del (p.Val1918GlufsTer87), which was absent in either parent, indicating a de novo mutation. According to the guidelines of the American College of Medical Genetics and Genomics, this was classified as a "pathogenic variant" leading to a diagnosis of Zhu-Tokita-Takenouchi-Kim (ZTTK) syndrome. Upon admission, symptomatic supportive treatment was provided. Follow-up at the age of 8 months revealed persistent stridor; the infant could only consume small amounts of milk and was unable to sit steadily. This patient represents the youngest reported case to date, and his symptoms expand the clinical spectrum of the disease, providing valuable insights for clinical diagnosis and treatment.

PMID:40105086 | DOI:10.7499/j.issn.1008-8830.2409076

Arq Neuropsiquiatr. 2025 Feb;83(2):1-6. doi: 10.1055/s-0045-1804920. Epub 2025 Mar 19.

ABSTRACT

BACKGROUND: Patients with neuromuscular diseases (NMDs) often face swallowing difficulties (dysphagia) as part of their condition.

OBJECTIVE: To determine the prevalence of self-reported swallowing disorders in patients with rare NMDs and examine their correlation with related quality of life (QoL).

METHODS: The study included 103 patients with confirmed rare NMDs. Dysphagia risk was assessed using the validated Eating Assessment Tool-10 (EAT-10), and QoL related to swallowing was measured with the SWAL-QoL survey. Correlations between EAT-10 and SWAL-QoL scores were analyzed. Additionally, the mean questionnaire scores were compared among patients classified as dysphagic, dysphagic with high aspiration risk, and nondysphagic.

RESULTS: The estimated prevalence of dysphagia in the cohort, based on EAT-10, was 52.4%. Higher scores were significantly correlated with poorer swallowing-related QoL, except for the sleep domain. The most affected SWAL-QoL domains were burden, eating desire, eating duration, food selection, communication, fear, mental health, social functioning, and dysphagia battery score (DBS), with significant differences observed among the classifications (p < 0.001 for most domains, and p = 0.015 for eating desire). No statistically significant difference in swallowing QoL was found between sitters and walkers.

CONCLUSION: Dysphagia is a prevalent symptom in patients with rare NMDs, affecting 52.4% of the cohort and significantly impacting QoL in nearly all domains except sleep.

PMID:40107292 | DOI:10.1055/s-0045-1804920

Tokai J Exp Clin Med. 2025 Apr 20;50(1):34-36.

ABSTRACT

A 19-year-old woman with three seborrheic keratosis on her right abdomen and five seborrheic keratosis on her both buttocks is presented. That developed at the age of five and two months prior to the visit. At our initial dermatological examination, we noticed three oval, well defined, brown tumors on her right abdomen, and several round, well defined, brown nodules on her both buttocks. Dermoscopy findings showed comedo-like openings, fissures, and ridges. Histopathological examination showed hyperkeratosis and pseudohorn cysts, and basaloid keratinocytes proliferation with no dysplastic cells. These findings were consistent with SK. She was treated by cryotherapy using a liquid nitrogen spray, and her tumors and nodules dropped off entirely. Juvenile-onset of seborrheic keratosis is quite rare in East Asian countries and needs to be differentiated from keratinocytic epidermal nevus.

PMID:40105231