Thyroglossal duct cyst (TGDC) is the most common congenital cervical anomaly. Although typically located in the midline, it may present with atypical locations. The main concern remains malignant transformation. The aim of this study was to describe the epidemiological, clinical, and histopathological features of TGDC.

This was a retrospective descriptive study including all cases of TGDC diagnosed at the Department of Pathology and Cytology of the Joseph Ravoahangy Andrianavalona University Hospital over a 10-year period, from January 2016 to December 2025.

During the study period, eighteen cases were identified. Patient age ranged from 1 month to 60 years, with a mean of 21.9 ± 20.8 years, and a predominance of patients older than 10 years (55.6%). The sex ratio was 0.5. The main clinical presentation was a midline cervical swelling (55.6%), while 16.7% of cases had an intrathyroidal location. Ectopic thyroid tissue was present in 27.8% of cases. Two cases of associated papillary carcinoma were identified in women aged 30 and 51 years.

 Although rare, malignant transformation of TGDC warrants systematic histopathological examination and careful follow up, particularly in adults.