Partial Thyroidectomy for Papillary Thyroid Microcarcinoma: Is Completion Total Thyroidectomy Indicated?

Background: Total thyroidectomy is a well-established surgical approach for the management of papillary thyroid cancer (PTC). However, the best surgical approach for papillary microcarcinoma is nowadays still debated. Both total thyroidectomy and simple lobectomy are used. We report the experience of a single University center in the treatment of thyroid microcarcinoma.
Methods: A retrospective analysis on all patients who underwent thyroid surgery at our institution over a 24-year period (1991-2015) was performed. Patients were grouped according to whether they received total thyroidectomy (Group 1) or lobectomy (Group 2). Follow-up was made by routine clinical and ultrasound examination. Specific outcomes such as recurrence and need for reoperation as well as complications (transient vocal cord paralysis and hypocalcemia) were analyzed.
Results: During the study period 880 patients underwent surgery for PTC. Group 1 and 2 consisted, respectively, of 756 and 124 patients. A micro PTC (<10 mm) was present in 251 and 69 specimen of Group 1 and 2. No evidence of disease recurrence in the follow-up was reported in patients with microPTC in Group 1 and in 57 patients of Group 2. In the remaining 12 patients completion thyroidectomy was carried out due to ultrasound findings of contralateral nodules (10), lymphadenopathy (1), and capsular invasion (1). Five of these patients had a contralateral papillary carcinoma on final histopathologic examination. Thus recurrence rate for patients of Group 2 was 7.3%. Morbidity rates were, respectively, for Group 1 and 2: transient nerve palsy 81 and 5 (11 vs. 7.3%, p = ns), transient hypoparathyroidism (Calcium <2.00 mmol/L) 137 (18.6%) and 0 (p < 0.0001). Three of the 12 patients of Group 2 undergoing further surgery had a transient hypoparathyroidism.
Conclusions: Thyroid lobectomy is an effective surgical strategy to manage papillary microcarcinomas with low complications. Routine completion thyroidectomy is not mandatory. Appropriate selection excluding high-risk patients is of paramount importance in order to achieve the best results.