Total Thyroidectomy Versus Lobectomy for Thyroid Cancer: Single-Center Data and Literature Review

Abstract

Background: Controversies remain about the ideal risk-based surgical approach for differentiated thyroid cancer (DTC).

Methods: At a single tertiary care institution, 370 consecutive patients with low- or intermediate-risk DTC were submitted to either lobectomy (LT) or total thyroidectomy (TT) and were followed up.

Results: Event-free survival by Kaplan-Meier curves was significantly higher after TT than after LT for the patients with either low-risk (P = 0.004) or intermediate-risk (P = 0.032) tumors. At the last follow-up visit, the prevalence of event-free patients was higher in the TT group than in the LT low-risk group (95% and 87.5%, respectively; P = 0.067) or intermediate-risk group (89% and 50%; P = 0.008). No differences in persistence prevalence were found among microcarcinomas treated by LT or TT (low risk, P = 0.938 vs. intermediate-risk, P = 0.553). Nevertheless, 15% of the low-risk and 50% of the intermediate-risk microcarcinomas treated by LT were submitted to additional treatments. On the other hand, macrocarcinomas were significantly more persistent if treated with LT than with TT (low-risk, P = 0.036 vs. intermediate-risk, P = 0.004). Permanent hypoparathyroidism was more frequent after TT (P = 0.01). After LT, thyroglobulin (Tg)/thyroid-stimulating hormone (TSH) had shown decreasing trend in 68% of the event-free patients and an increasing trend in the persistent cases.

Conclusions: Lobectomy can be proposed for low-risk microcarcinomas, although in a minority of cases, additional treatments are needed, and a longer follow-up period usually is required to confirm an event-free outcome compared with that for patients treated with TT. On the other hand, to achieve an excellent response, TT should be favored for intermediate-risk micro- and macro-DTCs despite the higher frequency of postsurgical complications.

Fig. 1

The entire clinical history of the two patient groups, including the first initial treatment and the eventual need for additional treatments up to the report of the final outcome. Additional treatments were performed in case of progressive disease, either biochemical or structural. AT additional treatments, LN lymph node metastases, prD progressive disease, sD stable structural disease, bD stable biochemical disease

Fig. 2

Upper panel: 20-year Kaplan–Meier curves by censorship of patients at the time of event-free confirmed definition or in the case of persistent/relapsing disease at the last clinical evaluation. The log-rank test was used to determine the P values. The patients who underwent total thyroidectomy had a better remission probability than those who underwent lobectomy (P = 0.004 for low-risk differentiated thyroid cancers [DTCs] and P = 0.032 for intermediate-risk DTCs). *Among the low-risk microcarcinomas, additional treatments were needed for none of the patients treated with total thyroidectomy (TT) and for 15% of those treated with lobectomy (LT). **Among the intermediate-risk microcarcinomas, additional treatments were needed for none of the patients treated with TT and for 50% of those treated with LT

Fig. 3

Basal thyroglobulin (Tg) and Tg/thyroid-stimulating hormone (TSH) levels in patients treated with lobectomy (LT) and in remission (left panel) or in persistence (right panel). The values refer to the evaluation during the follow-up period for the event-free patients (mean, 51 months; median,44 months; range, 12–110 months) and the patients in persistence (mean, 34.5 months; median, 27 months; range, 15–80 months), and at the end of the follow-up period for the event-free patients (mean, 131.4 months; median, 106 months; range, 16–483 months) and the patients in persistence (mean, 135.3 months, median, 110 months; range, 15–324 months). The patients with positive anti-thyroglobulin autoantibodies (TgAb) are shown. Among the 41 event-free patients after LT, a decreasing trend was observed in 28 cases (mean percentage change, − 55% ± 0.27%), whereas among the remaining 13 patients the Tg/TSH ratio remained stable. Four of the patients in persistence showed an increase in the level of Tg/TSH (mean percentage change, + 116% ± 0.95%), whereas among the remaining cases, Tg was stable due to the presence of TgAb