Parental Assessment of Infantile Hemangioma Cosmetic Clinical Outcomes: Results of the Spanish Hemangioma Nationwide Prospective Cohort.

BACKGROUND: Functional impairment is the main consideration when it comes to choosing therapy for infantile hemangiomas (IH). However, since most hemangiomas are treated for cosmetic reasons, it is important to know the cosmetic outcome assessed by the parents. OBJECTIVE: To evaluate the aesthetic outcomes of IH, considering the characteristics of the lesions and the treatments used. PATIENTS AND METHODS: The Spanish Infantile Hemangioma Nationwide Prospective Cohort (2016-2022) recruited all consecutive patients diagnosed with IH in 12 Spanish hospitals. The children included had two photos of the IH lesion (at both baseline and at the end of the study). A panel of parents blindly assessed all available photos using a scale from 0 (worst cosmetic outcomes) to 10 (best cosmetic outcomes). The different scores - both before and after treatment - as well as the outcomes percent considered excellent (>9) were described and compared. We analyzed the effect of receiving different therapies and performed causal model analyses estimating the mean treatment effect of parents' assessments. RESULTS: The median follow-up was 3.1 years. A total of 824 photos were evaluated. Baseline aesthetic impact was higher in the propranolol group vs the topical timolol and observation treatment groups (1.85 vs 3.14 vs 3.66 respectively; p<0.001). After treatment, the aesthetic impact was similar between both treatment groups (7.59 vs 7.93 vs 7.90; p>0.2). The causal model could only be applied to the comparison between topical timolol and observation, revealing no differences whatsoever. CONCLUSION: This is the first prospective cohort to analyze the aesthetic outcome of IH. The final aesthetic results of the three therapies were similar, with nearly 40% of patients achieving excellent aesthetic outcomes.

[Translated article] Requirements for Accessing New Dermatology Drugs in Spain: Results of the EQUIDAD Study.

BACKGROUND: Although the Spanish Ministry of Health prepares national therapeutic positioning reports (TPRs) and drug reimbursement policies, each of the country's 17 autonomous communities (ACs) is responsible for health care services and prescription requirements in its territory. The aim of the EQUIDAD study was to describe and explore potential differences in prescription requirements for new dermatology drugs across the autonomous communities. MATERIAL AND METHODS: Cross-sectional study conducted in April and May, 2023. Two dermatologists with management responsibilities from each autonomous community reported on territorial and more local prescription requirements for drugs covered by national TPRs issued between 2016 and 2022. RESULTS: Thirty-three researchers from 17 autonomous communities participated. The data submitted revealed between-community inequities in access to new drugs. Overall, 64.7% of the regions imposed additional prescription requirements to those mentioned in the TPRs for psoriasis. This percentage was lower for atopic dermatitis (35.3%) and melanoma (11.8%). The most common requirement for accessing a new drug was a previous prescription for another drug. Differences and additional requirements were also detected at the local level (i.e., differences between hospitals within the same autonomous community). CONCLUSIONS: Spain's autonomous communities have multiple regional and local prescription requirements that are not aligned with national TPR recommendations. These differences result in inequitable access to new drugs for both patients and practitioners across Spain.

Requirements for Accessing New Dermatology Drugs in Spain: Results of the EQUIDAD Study. / Condicionantes de acceso a nuevos medicamentos dermatológicos en España: resultados del proyecto EQUIDAD.

BACKGROUND: Although the Spanish Ministry of Health prepares national therapeutic positioning reports (TPRs) and drug reimbursement policies, each of the country's 17 autonomous communities (ACs) is responsible for health care services and prescription requirements in its territory. The aim of the EQUIDAD study was to describe and explore potential differences in prescription requirements for new dermatology drugs across the autonomous communities. MATERIAL AND METHODS: Cross-sectional study conducted in April and May, 2023. Two dermatologists with management responsibilities from each autonomous community reported on territorial and more local prescription requirements for drugs covered by national TPRs issued between 2016 and 2022. RESULTS: Thirty-three researchers from 17 autonomous communities participated. The data submitted revealed between-community inequities in access to new drugs. Overall, 64.7% of the regions imposed additional prescription requirements to those mentioned in the TPRs for psoriasis. This percentage was lower for atopic dermatitis (35.3%) and melanoma (11.8%). The most common requirement for accessing a new drug was a previous prescription for another drug. Differences and additional requirements were also detected at the local level (i.e., differences between hospitals within the same autonomous community). CONCLUSIONS: Spain's autonomous communities have multiple regional and local prescription requirements that are not aligned with national TPR recommendations. These differences result in inequitable access to new drugs for both patients and practitioners across Spain.

Nonvenereal Infections in Spanish Dermatology Clinics: Results of the DIADERM Study. / Enfermedades infecciosas no venéreas atendidas en consultas de Dermatología en España: resultados del estudio DIADERM.

BACKGROUND AND OBJECTIVE: The burden of nonvenereal infections in Spanish dermatology practice has not yet been evaluated. The aim of this study was to analyze the overall weight of these infections in outpatient dermatology caseloads. MATERIAL AND METHODS: Observational cross-sectional study of diagnoses made by a random selection of dermatologists from the Spanish Association of Dermatology and Venereology (AEDV) working in outpatient dermatology clinics. The data were obtained through the anonymous DIADERM survey. Diagnoses of infectious diseases were selected using codes from the International Classification of Diseases, Tenth Revision. After excluding sexually transmitted infections, the diagnoses were classified into 22 groups. RESULTS: Spanish dermatologists diagnosed an estimated 16190 (95% CI, 9338-23042) nonvenereal infections on average per week, a figure that accounted for 9.33% of the dermatology caseload. The most common diagnostic groups were nonanogenital viral warts (7475 diagnoses, 46.17% of nonvenereal infections), dermatophytosis (3336, 20.61%), and other viral infections (1592, 9.84%), which included Molluscum contagiosum infections. Nonvenereal infections were more common than noninfectious dermatologic conditions in private clinics (P<.0020) and adults (P<.00001). Patients with these infections were also more likely to be discharged than those with other conditions in both public (P<.0004) and private (P<.0002) practices. CONCLUSIONS: Nonvenereal infections are frequent in dermatology. They are the third most common reason for outpatient visits, behind actinic keratosis and nonmelanoma skin cancer. By enhancing the participation of dermatologists in the management of skin infections and encouraging interactions with other specialists, we will be able to carve out a niche in an area we have scarcely ventured into to date.

Primary Cutaneous Lymphoma Registry of the Spanish Academy of Dermatology and Venereology (AEDV): Data for the First 5 Years. / Registro de linfomas cutáneos primarios (RELCP) de la AEDV: datos tras 5 años de funcionamiento.

BACKGROUND AND OBJECTIVE: Primary cutaneous lymphomas (PCL) are uncommon. Observations based on the first year of data from the Spanish Registry of Primary Cutaneous Lymphomas (RELCP, in its Spanish abbreviation) of the Spanish Academy of Dermatology and Venereology (AEDV) were published in February 2018. This report covers RELCP data for the first 5 years. PATIENTS AND METHODS: RELCP data were collected prospectively and included diagnosis, treatments, tests, and the current status of patients. We compiled descriptive statistics of the data registered during the first 5 years. RESULTS: Information on 2020 patients treated at 33 Spanish hospitals had been included in the RELCP by December 2021. Fifty-nine percent of the patients were men; the mean age was 62.2 years. The lymphomas were grouped into 4 large diagnostic categories: mycosis fungoides/Sézary syndrome, 1112 patients (55%); primary B-cell cutaneous lymphoma, 547 patients (27.1%); primary CD30+lymphoproliferative disorders, 222 patients (11%), and other T-cell lymphomas, 116 patients (5.8%). Nearly 75% of the tumors were registered in stage I. After treatment, 43.5% achieved complete remission and 27% were stable at the time of writing. Treatments prescribed were topical corticosteroids (1369 [67.8%]), phototherapy (890 patients [44.1%]), surgery (412 patients [20.4%]), and radiotherapy (384 patients [19%]). CONCLUSION: The characteristics of cutaneous lymphomas in Spain are similar to those reported for other series. The large size of the RELCP registry at 5 years has allowed us to give more precise descriptive statistics than in the first year. This registry facilitates the clinical research of the AEDV's lymphoma interest group, which has already published articles based on the RELCP data.

Analysis of Undergraduate Dermatology Syllabi at Spanish Universities: Does the Weight of Theoretical Content Match the Skin Conditions Seen in Primary Care and General Dermatology Practices? / Análisis de las características de la docencia de pregrado de Dermatología en las universidades españolas. ¿Los contenidos teóricos se aproximan a la casuística de los médicos de Atención Primaria y dermatólogos generales?

INTRODUCTION: Undergraduate dermatology courses vary in the nearly 50 Spanish medical faculties that teach the subject. This study aimed to describe the characteristics of these courses and to analyze whether the weight assigned to dermatology topics reflect the caseloads of primary care physicians and general dermatologists in the Spanish national health system. MATERIAL AND METHODS: Cross-sectional study of syllabi used in Spanish medical faculties during the 2021-2022 academic year. We determined the number of teaching hours in public and private university curricula and compared the weight of dermatology topics covered to the dermatology caseloads of primary care physicians and general dermatologists as reported in published studies. RESULTS: Most medical faculties taught dermatology for one semester. The median number of credits offered was 4.5. On average, lectures covered 24 theoretical topics, and seminars and workshops covered 9 topics. We identified a clear disparity between the percentage of time devoted to dermatology topics in course lectures and the skin conditions usually managed in primary care and general dermatology practices. DISCUSSION: The skin diseases most commonly treated by primary care physicians and general dermatologists are underrepresented in the curricula of Spanish medical faculties. The topics that should be given more weight in syllabi, or recovered for inclusion in dermatology courses, should be re-examined. Our findings show that the topics that ideally should be emphasized more are types of dermatitis, infectious skin diseases, acne, psoriasis, rashes, and the differential diagnosis of benign and malignant neoplasms. There should be additional support for the theoretical teaching of these topics.

Risk of a Second Skin Cancer in a Cohort of Patients With Nonmelanoma Skin Cancer -Basal Cell Carcinoma or Squamous Cell Carcinoma-Treated With Mohs Micrographic Surgery: A National Prospective Cohort Study. / Riesgo de aparición de segundas neoplasias cutáneas en una cohorte de pacientes diagnosticados de carcinoma queratinocítico (carcinoma basocelular y carcinoma epidermoide) tratados con cirugía de Mohs. Estudio de cohortes prospectivo nacional.

OBJECTIVE: Patients with nonmelanoma skin cancer (NMSC)-ie, basal cell carcinoma (BCC) or squamous cell carcinoma (SCC)-have an increased risk of developing a second skin cancer. The aim of this study was to describe the frequency, incidence per 1000 person-years, and predictors of a second skin cancer in a cohort of patients with NMSC treated with Mohs micrographic surgery (MMS). MATERIAL AND METHODS: Prospective study of a national cohort of patients with NMSC who underwent MMS at 22 Spanish hospitals between July 2013 and February 2020; case data were recorded in the REGESMOHS registry. The study variables included demographic characteristics, frequency and incidence per 1000 person-years of second skin cancers diagnosed during the study period, and risk factors identified using mixed-effects logistic regression. RESULTS: We analyzed data for 4768 patients who underwent MMS; 4397 (92%) had BCC and 371 (8%) had SCC. Mean follow-up was 2.4 years. Overall, 1201 patients (25%) developed a second skin cancer during follow-up; 1013 of the tumors were BCCs (21%), 154 were SCCs (3%), and 20 were melanomas (0.4%). The incidence was 107 per 1000 person-years (95% CI, 101-113) for any cancer, 90 per 1000 person-years (95% CI, 85-96) for BCC, 14 (95% CI, 12-16) per 1000 person-years for SCC, and 2 (95% CI, 1-3) per 1000 person-years for melanoma. More men than women developed a subsequent skin cancer (738 [61%] vs 463 [39%]). The main risk factors were a history of multiple tumors before diagnosis (relative risk [RR], 4.6; 95% CI, 2.9-7.1), immunosuppression (RR, 2.1; 95% CI, 1.4-3.1), and male sex (RR, 1.6; 95% CI, 1.4-1.9). CONCLUSION: Patients have an increased risk of developing a second tumor after MMS treatment of NMSC. Risk factors are a history of multiple tumors at diagnosis, immunosuppression, and male sex.

What Proportion of the Spanish Dermatology Caseload Corresponds to Primarily Sexually Transmitted Infections and Other Anogenital Dermatoses? Results From the DIADERM National Random Survey. / ¿Cuánta carga asistencial suponen las infecciones de transmisión predominantemente sexual y otras dermatosis anogenitales en las consultas de Dermatología en España? Resultados del muestreo aleatorio nacional DIADERM.

BACKGROUND AND OBJECTIVE: Predominantly sexually transmitted infections (STIs) and infestations and other anogenital dermatoses are covered in the training of specialists in dermatology and venereology in Spain. This study aimed to analyze the proportion of the dermatology caseload these diseases account for within the public and private dermatological activity of the Spanish health system. MATERIAL AND METHODS: Observational cross-sectional study of time periods describing the diagnoses made in outpatient dermatology clinics, obtained through the anonymous DIADERM survey of a representative random sample of dermatologists. Based on diagnostic codes of the International Classification of Diseases, Tenth Revision, 36 related diagnoses were selected, and classified into 12 groups. RESULTS: Only 3.16% of diagnoses corresponded to STIs and other anogenital dermatoses. The most common diagnostic group was anogenital human papillomavirus infection, followed by molluscum contagiosum, and inflammatory anogenital dermatoses. Lesions with these diagnoses were usually the main reasons for first visits in the National Health Service. In private practice, the diagnoses usually came after referrals from other physicians. CONCLUSIONS: STIs and other anogenital dermatoses account for a very small proportion of the dermatology caseload in Spain, although the inclusion of molluscum contagiosum diagnoses overestimates these conditions. The fact that no STI centers or monographic STI consultations were included in the random sample of dermatology partly explains the under-representation of these areas of the specialty. A determined effort to support and promote monographic STI centres and clinics should be made.

Baseline description of the Spanish Academy of Dermatology infantile haemangioma nationwide prospective cohort. Comparison of patients treated with propranolol in routine clinical practice with previous pivotal clinical trial data. / Descripción basal de la cohorte prospectiva de hemangioma infantil a nivel nacional de la Asociación Española de Dermatología. Comparación de los pacientes tratados con propranolol en la práctica clínica rutinaria y los datos de un ensayo clínico pivotal previo.

BACKGROUND: There are several therapeutic options for infantile haemangiomas (IH). Propranolol is used according to a pivotal trial. We aimed to describe the characteristics of IH in clinical practice, including the therapies used, and to compare the characteristics of patients treated with propranolol with those of the trial to assess its external validity. METHODS: Consecutive patients attending 12 Spanish hospitals from June 2016 to October 2019 were included (n=601). RESULTS: The mean age was 3.9 (SD:1.9) months, with a 2:1 female-to-male ratio. Most IHs were localized (82%, 495), superficial (64%, 383) and located in the face (25%, 157) and trunk (31%, 188). Median size was 17 (IR: 10-30) x 12 (IR: 7-20) mm. Complications were found in 16 (3%) patients. Treatment was initiated for 52% (311). Most patients received timolol (76%, 237); propranolol was reserved for complications or high-risk IHs. Aesthetic impairment was the main reason for starting therapy (64%, 199). Several characteristics of the patients and IHs treated with propranolol are similar to those of the pivotal clinical trial, but 1/3 of IHs did not reach the minimum diameter to meet the inclusion criteria, and important prognostic information was not reported. CONCLUSIONS: As most patients receive treatment for aesthetic impairment, there is a need to better understand the aesthetic results of therapies and to increase evidence on the use of timolol, which is currently the most common therapy. Propranolol is being used in a population generally similar to that of the trial; however, this statement cannot be definitely confirmed.

Interobserver variability in the classification of childhood maculopapular cutaneous mastocytosis.

BACKGROUND: Maculopapular cutaneous mastocytosis (MPCM) in children is classified in two variants: (i) monomorphic variant, presenting with the small macules or papules typically seen in adult patients; and (ii) polymorphic variant with larger lesions of variable size and shape, typically seen in children. The definition of polymorphic and monomorphic variants is mostly intuitive, and a validation of this classification has not been done. OBJECTIVE: To study interobserver variability in the classification of MPCM in two groups of observers: mastocytosis experts and general dermatologists. MATERIALS AND METHODS: Nineteen cases of childhood MPCM were shown blindly, for classification as monomorphic or polymorphic type, to 10 independent observers (eight dermatologists, one allergist and one haematologist) from Europe and North America with a vast experience in the management of paediatric mastocytosis. Also, the same cases were shown on a screen to 129 general dermatologists attending a meeting; their votes were registered by remote controls. The interobserver variability kappa coefficient (with 95% confidence interval) was calculated to measure the reliability of the correlation. RESULTS: The value of kappa interobserver variability coefficient for the group of 10 experts (95% confidence interval) was 0.39 (0.18-0.63), which is considered as 'fair'. The value of kappa interobserver variability coefficient for the group of 129 general dermatologists (95% confidence interval) was 0.17 (0.06-0.39), which is considered as 'slight'. A complete agreement of all 10 experts was achieved in only four of 19 cases (21.1%) The most voted choice was concordant between the two groups in only 11 of the 19 cases. CONCLUSIONS: We failed to validate the classification system of childhood MPCM in monomorphic and polymorphic types. While the rate of agreement was low for mastocytosis experts, it was nearly the agreement expected by chance in general dermatologists.

What Proportion of the Caseload at Dermatology Outpatient Clinics in Spain Do Skin Tumors Account for? Results from the DIADERM National Random Sampling Project. / ¿Cuánta carga asistencial supone la enfermedad tumoral cutánea en la actividad ambulatoria en la Dermatología española? Resultados del muestreo aleatorio nacional DIADERM.

INTRODUCTION AND OBJECTIVE: A significant part of a dermatologist's activity involves the diagnosis and management of tumors. The aim of this study was to analyze the caseload at public and private dermatology outpatient clinics in Spain to determine the proportion of tumor diagnoses. MATERIAL AND METHOD: Observational cross-sectional study of diagnoses made in dermatology outpatient clinics during 2 data-collection periods in the DIADERM study, an anonymous survey of a random, representative sample of dermatologists across Spain. Diagnoses made during the 2 periods were coded according to the CIE-10. There were 165 tumor-related codes, classified into 24 groups. For the purpose of this study, these groups were then reduced to benign melanocytic lesions, malignant melanocytic lesions, benign nonmelanocytic lesions, and malignant nonmelanocytic lesions. RESULTS: Tumors accounted for 46.2% of all diagnoses; 18.5% of the tumors were malignant (a category that included in situ forms of keratinocyte cancers). Four of the 10 most common diagnoses were of malignant tumors: in situ keratinocyte cancers, basal cell carcinoma, melanoma, and squamous cell carcinoma. Significant differences were observed between malignant and benign tumors according to type of practice (public vs. private) and geographic region. CONCLUSION: Skin cancer accounts for a significant part of the dermatologist's caseload in Spain. Differences can be observed depending on the public/private healthcare setting and other factors.

EuroGuiDerm Guideline on the systemic treatment of Psoriasis vulgaris - Part 2: specific clinical and comorbid situations.

This evidence- and consensus-based guideline on the treatment of psoriasis vulgaris was developed following the EuroGuiDerm Guideline and Consensus Statement Development Manual. The second part of the guideline provides guidance for specific clinical and comorbid situations such as treating psoriasis vulgaris patient with concomitant psoriatic arthritis, concomitant inflammatory bowel disease, a history of malignancies or a history of depression or suicidal ideation. It further holds recommendations for concomitant diabetes, viral hepatitis, disease affecting the heart or the kidneys as well as concomitant neurological disease. Advice on how to screen for tuberculosis and recommendations on how to manage patients with a positive tuberculosis test result are given. It further covers treatment for pregnant women or patients with a wish for a child in the near future. Information on vaccination, immunogenicity and systemic treatment during the COVID-19 pandemic is also provided.

Clinical Practice Guideline on Melanoma From the Spanish Academy of Dermatology and Venereology (AEDV). / Guía de práctica clínica de melanoma de la Academia Española de Dermatología y Venereología.

Specialist approaches to the diagnosis and treatment of melanoma have undergone many changes. This guideline aims to provide Spanish dermatologists with evidence-based information for resolving the most common doubts that arise in clinical practice. Members of the Spanish Oncologic Dermatology and Surgery Group (GEDOC) with experience treating melanoma were invited to participate in drafting the guideline. The group developed a new guideline on the basis of existing ones, using the ADAPTE collaboration process, first summarizing the care process and posing relevant clinical questions, then selecting guidelines with the best scores according to the AGREE II (Appraisal of Guidelines for Research and Evaluation) tool. Finally, the group searched the selected guidelines for answers to the clinical questions, drafted recommendations, and sent them for external review. The guideline is structured around 21 clinical questions chosen for their relevance to issues that make clinical decisions about the management of melanoma difficult. Evidence from existing guidelines was used to answer the questions. A limitation of this guide derives from the scarce evidence available for answering some questions. Moreover, some areas are changing rapidly, so recommendations must be updated often. The present guideline offers answers to clinical questions about the routine management of melanoma in clinical practice and provides dermatologists with a reference to guide decisions, taking into consideration the resources available and patient preferences.

Changing Trends in Drug Prescription and Causes of Treatment Discontinuation of First Biologic Over Ten Years in Psoriasis in the Spanish Biobadaderm Registry. / Cambios en las tendencias de la prescripción y causas de la interrupción en los tratamientos biológicos indicados en la psoriasis durante los primeros 10 años. Datos obtenidos del registro español Biobadaderm.

BACKGROUND AND OBJECTIVES: Current psoriasis guidelines do not usually include recommendations about first line classical or biologic treatment. The objectives of this study were: to describe shifts in the prescription of the first biological treatment, and to compare treatment withdrawal and rates of adverse events over ten years. MATERIAL AND METHODS: Biobadaderm registry was analyzed to describe: first biological prescription in bio-naïve patients, adverse events rate and reasons for drug withdrawal comparing three periods of time (2008-2010, 2011-2014, 2015-2018). RESULTS: Anti-TNF drugs were the most prescribed biological drug from 2008 to 2010. Ustekinumab has become the most prescribed first biologic since 2014. The main reasons for drug discontinuation were adverse events, lack of efficacy and remission. In each period any treatment was less likely to be discontinued due to any of these three reasons comparing to the previous period. CONCLUSIONS: The present study identifies trends in prescription of the first biological antipsoriatic drug in clinical practice from 2008 to 2018. It suggests that we have become more comfortable with the safety profile and more exigent with the efficacy of the drugs.

Diagnosis and Treatment of Basal Cell Carcinoma in Specialized Dermatology Units: A Clinical Practice Guideline. / Carcinoma basocelular cutáneo: diagnóstico y tratamiento en atención especializada dermatológica. Guía de Práctica Clínica de la AEDV.

BACKGROUND AND OBJECTIVE: Basal cell carcinoma (BCC) is the most common skin cancer in the general population. BCC is managed in a variety of ways, and available international guidelines are difficult to put into practice in Spain. This guideline aims to improve the management of BCC based on current evidence and provide a point of reference for Spanish dermatologists. MATERIAL AND METHODS: Members of the Spanish Oncologic Dermatology and Surgery Group (GEDOC) with experience treating BCC were invited to participate in drafting this guideline. The drafters used the ADAPTE collaboration process to develop the new guideline based on existing ones, first summarizing the care pathway and posing relevant clinical questions. They then searched for guidelines, assessed them with the AGREEII (Appraisal of Guidelines for Research and Evaluation) tool, and searched the selected guidelines for answers to the clinical questions. Finally, the recommendations were drafted and submitted for external review. RESULTS: The highest-scoring guidelines were from the Association of Dermatologists, the National Comprehensive Cancer Network, the European Dermatology Forum, and the European Academy of Dermatology and Venereology. A total of 11 clinical questions were answered. CONCLUSIONS: This new guideline answers the working group's clinical questions about the routine management of BCC in Spain. It provides dermatologists with a tool they can use for decision-making while taking into consideration the resources available and patient preferences.

TREatment of ATopic eczema (TREAT) Registry Taskforce: protocol for a European safety study of dupilumab and other systemic therapies in patients with atopic eczema.

BACKGROUND: A long-term prospective observational safety study is essential to characterize fully the safety profile of systemic immunomodulating therapies for patients with atopic eczema. The TREatment of ATopic eczema (TREAT) Registry Taskforce offers a large platform to conduct such research using national registries that collect the same data using a predefined core dataset. OBJECTIVES: To present a protocol for a safety study comparing dupilumab with other systemic immunomodulating therapies in children and adults with moderate-to-severe atopic eczema, to assess the long-term safety risk of these therapies in a routine clinical care setting. METHODS: We describe a registry-embedded international observational prospective cohort study. Adult and paediatric patients who start treatment with dupilumab or another systemic immunomodulating agent for their atopic eczema will be included. The primary end point is the incidence of malignancies (excluding nonmelanoma skin cancer) compared between the treatment groups. Secondary end points include other serious adverse events and adverse events of special interest, such as eye disorders and eosinophilia. CONCLUSIONS: This protocol delineates a safety study for dupilumab in adult and paediatric patients with atopic eczema, using a standardized methodological approach across several national registries. The protocol could also be used for other novel systemic immunomodulating therapies, and could provide licensing and reimbursement authorities, pharmaceutical companies and clinicians with safety evidence from a routine clinical care setting. What's already known about this topic? There is a need for long-term data on the safety of systemic immunomodulating therapies in patients with atopic eczema. Regulatory bodies, such as the European Medicines Agency, increasingly stipulate the collection of such data as part of the licensing agreement for new treatments, to assess the new agent's long-term safety profile against established therapies. Large numbers of patients with a long duration of follow-up are necessary in order to detect rare events like malignancies. What does this study add? The TREAT Registry Taskforce offers a platform to conduct such research with a network of multiple national atopic eczema research registries. We present a protocol for an investigator-initiated multicentre safety study comparing dupilumab with other systemic immunomodulating therapies in adults and subsequently adolescents and children with moderate-to-severe atopic eczema. This protocol can be used as a framework for similar studies for other novel systemic immunomodulating therapies across both adult and paediatric populations.