RESUMEN Introduccion: El tumor trabecular hialinizante de tiroides es una condicion clinica incidental, infrecuente, de comportamiento incierto, representa un reto diagnostico y terapeutico debido a que es dificil diferenciarlo de otros tumores tiroideos como el carcinoma papilar y medular por sus similitudes histologicas. Reporte de caso: Paciente de 53 anos quien acudio a consulta por crecimiento de la glandula tiroidea y disfagia. Se realizaron estudios diagnosticos previos los cuales orientaron hacia una condicion benigna sin embargo por progresion de sintomas se decidio realizar tiroidectomia total. La histopatologia de la masa reporto carcinoma medular y en la inmunohistoquimica como hallazgo incidental se realiza diagnostico final de adenoma trabecular hialinizante de tiroides. Discusion: El tumor trabecular hialinizante de tiroides presenta un desafio continuo, por lo cual es necesario realizar pruebas inmunohistoquimicas que permitan realizar la diferenciacion. El abordaje quirurgico no es claro debido a su comportamiento incierto y a que las publicaciones que existen no son claras acerca del pronostico y manejo. Conclusiones: El tumor trabecular hialinizante de tiroides es una enfermedad con bajas tasas de incidencia, frecuentemente mal diagnosticado y sobre el cual no existe informacion clara acerca de su manejo. El seguimiento clinico de estos pacientes y futuros estudios observacionales nos permitira obtener conclusiones a futuro sobre su comportamiento y pronostico. Palabras Clave: Nodulo Tiroideo, Adenoma Trabecular, Carcinoma Medular, Carcinoma Papilar. Hyalinizing trabecular tumor of thyroid gland: diagnostic challenge, case report ABSTRACT Introduction: The hyalinized trabecular tumor of thyroids is a clinical condition, rarely frequent of uncertain behavior and difficult diagnosis due to the fact that is hard to differentiate it from other thyroid tumors such as the papillary and medullar carcinoma due to its histological similarities. Case report: 53 year old patient who attended medical consult because of an irregular growth in the thyroids gland and the dysphagia, previous diagnose studies were made and led to a benign pathology, but for symptomatology it was decided to make a total thyroidectomy. The histopathology of the mass reported a medullar carcinoma and in the immune-histo-chemistry as an incidental finding a final diagnose was made, showing a hyalinized trabecular adenoma of thyroids. Discussion: The hyalinized trabecular tumor of thyroids presented diagnosis and therapeutic challenges. Duo to is necessary necessary to make immune-histo-chemistry tests. The surgical approach is not clear because of its uncertain behavior and the lack of studies that report its forecast and treatment. Conclusion: The hyalinized trabecular tumor of thyroids is a disease with low rates of incidence, usually badly diagnosed, over which there is no clear existing information for its treatment. The clinical surveillance of these patients and future observational studies will allow us to make some conclusions in the future regarding its behavior and forecast. Keywords: Thyroid Nodule, Adenoma Trabecular, Carcinoma Medullary, Carcinoma Papillary. Forma de citar: Diaz Acosta JC, Forero Porras PL, Guarin Supelano DA, Alarcon Tarazona ML, Rangel Cantillo D. Tumor trabecular hialinizante de glandula tiroides: un reto diagnostico, a proposito de un caso. Rev.univ.ind.santander.salud 2014; 46(2):189-193.