Histological characterization of the thyroglossal tract: implications for surgical management

OBJECTIVES: In the current report, we characterized the relationship between the central hyoid bone and the thyroglossal tract and determined the prevalence of ectopic thyroid follicles in the adjacent soft tissues. STUDY DESIGN: Retrospective pathological analysis. METHODS: The resected specimens from 104 patients who underwent a modified Sistrunk procedure with wide-field dissection were retrospectively analyzed. Under light microscopy, serial sections were examined to determine whether the thyroglossal tract passed anterior to, posterior to, or within the hyoid bone. Specimens were also examined for the presence of thyroid follicles in the periductal and pericystic soft tissues. RESULTS: In 50 cases (48%), the tract position in relation to the hyoid bone could not be identified secondary to extensive arborization, marked inflammation, specimen fragmentation or a combination of these. Thyroid follicles were observed in 9 (18%) of these specimens. In the remaining 54 cases (52%) the tract was located anterior to the central arch of the hyoid bone in 39 (72%) and posterior to it in 15 (28%). Thyroid tissue was observed in 46% of specimens (P =.004), regardless of whether the tract was anterior or posterior. CONCLUSIONS: These results demonstrate that tract position often cannot be defined, but when a portion is dominant, it is likely to be anterior to the hyoid bone. Ectopic thyroid tissue can be found in almost 50% of specimens when the tract position is identifiable. With appropriate surgical management, a recurrence rate of less than 4% can be expected, despite the presence of ductule multiplicity, marked inflammation, tract position posterior to the hyoid bone, and ectopic thyroid follicles.