The time point of completion thyroidectomy has no prognostic impact in patients with differentiated thyroid cancer

Summary Background After partial resection of the thyroid gland, a second operation referred to as “completion thyroidectomy” may be required if histopathological analysis indicates the presence of differentiated thyroid cancer ( DTC ). Although there is little evidence, it is assumed that the time point of completion thyroidectomy is not critical for oncological prognosis of patients with DTC . We assessed whether patients with total thyroidectomy ( TT x) in a two‐step procedure have an equal long‐term prognosis with regard to disease‐specific survival (DSS) compared to patients immediately undergoing total thyroidectomy in a one‐step procedure. Methods A database study using the Würzburg thyroid cancer database with 2258 patients with pT 1a‐ pT 4b tumours DTC who were operated between 1980 and 2016 was carried out. Results A total of 277 patients with papillary microcarcinoma pT 1aN0M0 were treated by hemithyroidectomy. TT x as one‐step procedure was performed in 1114 patients compared to 867 with TT x as a two‐step procedure. Patients with papillary thyroid cancer more frequently had a TT x as one‐step procedure than follicular thyroid cancer patients (59.4% vs 47%; P  < 0.001). Compared to a one‐step thyroidectomy, overall complication rate was not different compared to patients undergoing a single operation. Multivariate analysis showed that the presence of distant metastases, T‐stage and age at diagnosis were the only independent determinants for DTC ‐specific survival, regardless of a one‐ or two‐time thyroidectomy. Conclusion The present study on the largest of such patient collectives provides evidence that a delayed completion operation does not affect DSS in DTC , nor does it lead to a significant increase in complication rates.