Total thyroidectomy versus lobectomy in conventional papillary thyroid microcarcinoma: Analysis of 8,676 patients at a single institution.

BACKGROUND: Because there is a controversy regarding the management of papillary thyroid microcarcinoma, the purpose of this study was to compare lobectomy with total thyroidectomy as a primary operative treatment for papillary thyroid microcarcinoma. Loco-regional recurrence in the contralateral remnant lobe can be managed safely by completion thyroidectomy via the previous scar. However, reoperation for operation bed (thyroidectomy site) or regional lymph node (central or lateral) recurrence generally is associated with morbidity. Therefore, we analyzed overall loco-regional recurrence and loco-regional recurrence outside of the contralateral remnant lobe separately.

METHODS: We retrospectively reviewed 8,676 conventional patients with papillary thyroid microcarcinoma who underwent thyroidectomy.

RESULTS: Lobectomy was performed in 3,289 (37.9%) patients, and total thyroidectomy was performed in 5,387 (62.1%) patients. Total thyroidectomy significantly decreased the risk of overall loco-regional recurrence (adjusted hazard ratio 0.398, P < .001). However, total thyroidectomy did not significantly decrease the risk of loco-regional recurrence outside of the contralateral remnant lobe (adjusted hazard ratio 0.880, P = .640). Particularly in conventional papillary thyroid microcarcinoma patients with multifocality, total thyroidectomy significantly decreased the risk of overall loco-regional recurrence (adjusted hazard ratio 0.284, P = .002) and loco-regional recurrence outside of the contralateral remnant lobe (adjusted hazard ratio 0.342, P = .020).

CONCLUSION: Although lobectomy is associated with contralateral remnant lobe recurrence, lobectomy did not increase the risk of loco-regional recurrence outside of the contralateral remnant lobe in patients with papillary thyroid microcarcinoma, except in those with multifocality. Because recurrence in the contralateral remnant lobe can be managed safely by completion thyroidectomy, lobectomy may be a safe operative option for select patients with papillary thyroid microcarcinoma without multifocality.