Patient-specific factors, patient preference, and nodule size as implications in the initial surgery of high risk indeterminate thyroid nodules.

Purpose: To evaluate the frequency of total thyroidectomy (TT) for thyroid nodules cytologically classified as high-risk indeterminate (TIR3B) and to explore the impact of patient specific factors (PSFs) (some clinical variables) associated with TT for follicular thyroid carcinoma (FTC). Moreover, we aim to investigate the nodule size as a factor influencing the risk of malignancy (ROM) and the risk of aggressiveness of FTC.

Methods: We retrieved consecutive FTC cases, and an equal number of follicular adenoma (FA) from adult patients with TIR3B thyroid nodules, which were operated in our Academic referral center between March 1, 2018, and December 31, 2024.

Results: We reviewed 112 TIR3B thyroid nodules, histologically subdivided into 56 FTC cases and 56 FA cases. TT was performed in 83% of cases. PSFs were present in 47.4% of patients undergoing hemithyroidectomy (HT) and in 61.3% of patients undergoing TT. No statistical significance was found for PSFs as predictors of TT. For the 30 mm ≤ dmax <40 mm size category we found an odds ratio (OR) of 2.0 [1.101; 3.551] (p-value 0.022) for risk of FTC. We found the existence of a positive relationship between dimensions of FTC and its aggressiveness.

Conclusion: TT was largely performed as initial surgery for TIR3B thyroid nodules. PSFs and patient preferences should be explored when planning the initial surgical management of a nodule with TIR3B cytology. Large nodule size (30 ≤ dmax < 40) can be integrated into decision making for patients with a cytology of TIR3B, since it increases the risk of FTC. Larger FTC seems to be more aggressive.