Endocrine Abstracts

Background: The thyroid pyramidal lobe (TPL) represents a normal anatomical variation of the thyroid gland. Intraoperative TPL identification is of paramount significance, taking into account that the remnant TPL leads to higher thyroglobulin, could contain thyroid carcinoma foci and lead to recurrence.

Methods: We conducted a prospective single-center, single-operator study to identify TPL in 1275 consecutive patients undergoing thyroid ultrasound for any indication. We extended the standard technique to actively search for TPL. The findings reported were presence and site of the TPL, presence of incidentally discovered nodules in TPL and thyroglossal duct cysts (TGDC). We excluded patients who underwent thyroid surgery or radioiodine therapy.

Results: Of the 1275 consecutive patients (1011 female), TPL was identified in 584 (45.8%), 12 (0.9%) had TGDC, 2 had hemiagenesis of the left thyroid lobe, 1 had thyroid agenesis with ectopic thyroid tissue. 227 patients (38.9%) presented with left-sided TPL, 220 (37.7%) with right-sided, 111 (19%) with median line and 26 (4.5%) with bilateral TPL. In 27 patients (4.6%), we identified incidental asymptomatic nodular lesions or possibly pseudonodular lesions (in some cases probably structural heterogeneity due to autoimmune thyroid disease) within TPL.

Conclusions: We suggest to routinely screen for thyroglossal duct remnants (TPL or TGDC) during thyroid ultrasound. This may reduce the rate of postoperative remnant TPL, obtain lower postoperative thyroglobulin levels and potentially lead to less frequent radioiodine therapy indication. Incidental discovery of thyroid nodules within TPL could also play important role in patient management. The investigation is not time-consuming (average time <10 seconds) and could be considered a cost-effective strategy.