Oncological impact of hypothyroidism and levothyroxine supplementation following hemithyroidectomy in patients with papillary thyroid carcinoma.

Abstract

We aimed to evaluate the oncological impact of hypothyroidism and levothyroxine (LT) supplementation after hemithyroidectomy in patients with papillary thyroid carcinoma (PTC). We retrospectively examined 401 patients who underwent hemithyroidectomy for classic PTC and who were postoperatively followed-up with ≥3 thyroid function measurements for ≥24 months. During 77.4 months of follow-up, 268/401 patients (66.8%) developed hypothyroidism and 19/401 patients (4.7%) showed recurrence. Recurrence rates did not differ between the euthyroidism and hypothyroidism development groups. Recurrence rates were significantly lower in the LT group than in the no-LT group, although mean postoperative thyroid-stimulating hormone (TSH) levels were not different between the two groups. Univariate and multivariate analysis showed that tumors sized >1 cm and lack of LT supplementation were significantly associated with recurrence. Postoperative hypothyroidism development was not a risk factor for PTC recurrence after hemithyroidectomy. Nevertheless, LT supplementation reduced recurrence risk without suppressing TSH.