Epidemiology and management of malignancies in patients with inborn errors of immunity - an ESID registry study of 19,959 patientsBogaert, Delfien J. A. (Avtor) Wolfsberger, Christina Helene (Avtor) Attarbaschi, Andishe (Avtor) Gathmann, Jonathan (Avtor) Warnatz, Klaus (Avtor) Mueller, Gabriele (Avtor) Mukhina, Anna (Avtor) Rusch, Stephan (Avtor) Kindle, Gerhard (Avtor) van Montfrans, Joris M. (Avtor) Seidel, Markus G. (Avtor) Avčin, Tadej (Sodelavec pri raziskavi) Blazina, Štefan (Sodelavec pri raziskavi) Meško Meglič, Karmen (Sodelavec pri raziskavi) Kopač, Peter (Sodelavec pri raziskavi) Markelj, Gašper (Sodelavec pri raziskavi) inborn errors of immunityIEIprimary immunodeficiencyPIDprimary immune disordermalignancycancer predisposition syndromestumor predispositionESID registryBackground Inborn errors of immunity (IEI), or primary immune disorders (PIDs), predispose individuals to infections, autoimmunity, inflammation, allergy, and malignancy. Malignancies are a major cause of morbidity and mortality in patients with IEI/PIDs, with poorer outcomes compared with the general population. Objective We sought to determine the frequency and types of malignancies in patients with IEI/PIDs and to assess clinical management approaches across Europe. Methods Descriptive analyses were performed on malignancy data within each IEI category. In addition, a European Society for Immunodeficiencies Registry survey (05/2022-03/2024) collected data on management strategies and challenges. Results Of 19,959 patients with IEI/PIDs, 1783 (8.9%) developed malignancies, of whom 27.1% presented malignancy as first manifestation of IEI/PIDs. A total of 1210 malignancies were specified; B-cell non-Hodgkin lymphoma was most common (24.2%). Detailed malignancy-IEI/PID association maps are provided. Predominantly antibody deficiencies accounted for 59.1% of malignancy cases, with a higher median age at first malignancy (43.6 years) compared with other IEI/PID categories, for example, combined immunodeficiencies with syndromic or associated features (11.7 years). Survey findings revealed that oncological treatment was modified because of IEI/PIDs in 21.5% of cases, with assumed negative impacts of IEI/PIDs on complications and outcomes (in 27.4% and 30.7%, respectively). IEI/PIDs influenced transplant decisions in 16.5% of cases. Management practices such as interdisciplinary decision finding and guideline availability were recorded. Conclusions This study provides comprehensive epidemiological data on malignancies in IEI/PIDs, highlighting the need for tailored screening and management. Survey results emphasize the real-world challenges and support the development of IEI/PID-specific oncological surveillance guidelines and treatment strategies.20262026-04-08 10:24:33Neznano28804sl