[ES] Introducci?n y objetivo: La mayor?a de las tumoraciones cervicales de la l?nea media son benignas. Las m?s frecuentes son los remanentes del conducto tirogloso, que pueden presentarse en cualquier etapa de la vida. La malignizaci?n de estas lesiones es rara (1%) y casi siempre son carcinomas tiroideos bien diferenciados de estirpe papilar. Se describe un hallazgo inhabitual. Descripci?n del caso: Presentamos el caso de una paciente de 70 a?os de edad, intervenida a?os antes de tiroidectom?a total con resultado de benignidad. Consulta por una tumoraci?n de 4 cm a nivel hioideo, con diagn?stico de carcinoma folicular de tiroides tras su ex?resis. Discusi?n: La prevalencia de los carcinomas diferenciados de tiroides sobre quistes tiroglosos es muy baja, y su diagn?stico suele ser postoperatorio, con histolog?a m?s frecuentemente papilar. Es excepcional el hallazgo de carcinomas foliculares. El tratamiento es la ex?resis quir?rgica y aunque existe cierta discusi?n, habitualmente se indica tambi?n la tiroidectom?a total seg?n el manejo est?ndar de los tumores diferenciados de tiroides. Conclusi?n: Aunque las tumoraciones de la l?nea media cervical son habitualmente benignas y corresponden m?s frecuentemente a quistes del conducto tirogloso, en lesiones muy voluminosas o de comportamiento agresivo debe sospecharse malignidad. [EN] Introduction and objective: Most cervical midline tumors are benign. The most common are the remnants of the thyroglossal duct, which can occur at any age. Malignancy is rare (1%) and they are usually well differentiated papillary thyroid carcinomas. We describe an unusual finding. Case description: We present a 70 year old patient, operated years before of a total thyroidectomy with a benign outcome. She is reported because of a tumor measuring 4 cm at the hyoid level, which is diagnosed as a follicular thyroid carcinoma after surgical resection. Discussion: The prevalence of differentiated thyroid carcinoma in thyroglossal cysts is very low, and its diagnosis is usually postoperative, most frequently with papillary histology. The follicular carcinoma is an exceptional finding. The treatment is surgical excision and although there is some discussion, usually total thyroidectomy is also indicated according to the standard management of differentiated thyroid gland tumors. Conclusion: Although midline cervical tumors are usually benign and most often correspond to thyroglossal duct cysts, malignancy should be suspected in bulky lesions or those with an aggressive behavior.