Thyrolipoma presentation as a huge multinodular goiter; A case report of an extremely rare entity

Importance and importance: Thyroid lipomatosis is a rare entity of thyroid gland lesions. The exact etiopathogenesis of this condition is unknown. Most patients presented with compression symptoms. Radiological investigations such as neck ultrasonography (U/S) and computed tomography (CT) are crucial to evaluate and diagnose fat-containing thyroid tumors, while the definitive diagnosis is achieved by the histopathological study.

Case presentation: A 78-year-old female patient, with a background medical history of diabetes mellitus type II and chronic kidney disease, presented to our hospital with a seven-month history of large-sized neck swelling. On physical examination, the neck mass was firm, nodular, hard in consistency, and asymmetrical. The neck swelling was associated with swallowing difficulties and minimal voice changes. Laboratory investigations were unremarkable. Neck U/S showed thyroid goiter. FNA and FNAC were also done. Then, neck CT was performed, and bilateral lobulated fat density was detected. So, a total thyroidectomy was performed, and the resected specimen was sent for histopathology studies. The postoperative period was uneventful.

Clinical discussion: Diffuse thyroid lipomatosis is an unusual non-neoplastic lesion. The clinical features of thyro-lipomatosis include compression symptoms. Radiological tools and cytology aid in diagnosis demonstration but the specific diagnosis is achieved by histopathology.

Conclusion: Due to the rare etiologic origin and unknown pathogenesis of thyrolipoma, we report the case of a 78-year-old female patient with enlarged neck swelling, found to be thyroid lipomatosis.