Aróstegui Aguilar, JDiago, ACarrillo Gijón, RFernández Figueras, MFraga, JGarcía Herrera, AGarrido, MIdoate Gastearena, M ÁChristian Laga, ÁLlamas-Velasco, MMartínez Campayo, NMonteagudo, COnrubia, JPérez Muñoz, NRíos-Martín, J JRíos-Viñuela, ERodríguez Peralto, J LRozas Muñoz, ESanmartín, OSantonja, CSantos-Briz, ÁSaus, CSuárez Peñaranda, J MVelasco Benito, VBeato Merino, M JFernandez-Flores, A2023-02-092023-02-092021-04-20http://hdl.handle.net/10668/17618This series of 2 articles on dermatopathologic diagnoses reviews conditions in which granulomas form. Part 1 clarifies concepts, discusses the presentation of different types of granulomas and giant cells, and considers a large variety of noninfectious diseases. Some granulomatous diseases have a metabolic origin, as in necrobiosis lipoidica. Others, such as granulomatous mycosis fungoides, are related to lymphomas. Still others, such as rosacea, are so common that dermatologists see them nearly daily in clinical practice.enAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/Célula de LanghansCélula de ToutonCélula giganteGiant Langhans cellGiant cellGranulomaTouton giant cellXanthogranulomaXantogranulomaresearch article33887235open access10.1016/j.ad.2021.04.0022173-5778https://doi.org/10.1016/j.ad.2021.04.002