Diagnosis and treatment of papillary thyroid microcarcinoma: report of 47 cases
Objective: To investigate the clinical characteristics of papillary thyroid microcarcinoma (PTMC) and its diagnosis and treatment strategies. Methods: The clinical and pathologic data of 47 patients with PTMC that was confirmed by surgical and pathological findings from June 2011 to May 2016 were retrospectively analyzed. Results: Of the 47 patients, 9 cases were male and 38 cases were female, with an average age of (46.3±12.1) years and average disease course of (12.4±23.7) months; all cases underwent preoperative ultrasound examination, and 14 cases underwent ultrasound-guided fine-needle aspiration biopsy (FNA) by which PTMC was diagnosed in 11 cases (78.6%); 13 cases underwent total resection of the affected lobe, 3 cases underwent total resection of affected lobe plus subtotal resection of the contralateral lobe, and 31 cases underwent total thyroidectomy; 14 cases underwent central neck dissection and 15 cases underwent central plus lateral neck dissection. The average axis diameter of the tumors was (0.68±0.23) cm, and 21 patients (44.7%) had multiple lesions, of whom, 14 cases (29.8%) had bilateral thyroid multiple lesions. Twenty-nine patients underwent cervical lymph node dissection and 48.3% (14/29) had central lymph node metastasis. The incidence of lateral lymph node metastasis was 53.3% (8/15). Univariate analysis showed that capsular invasion was significantly associated with lymph node metastasis (P=0.035). Postoperative complications occurred in 8 patients, including transient hypoparathyroidism in 5 cases, and incisional fluid collections and transient recurrent laryngeal nerve injury and superior laryngeal nerve injury in one case each. Conclusion: Thyroid surgeons should be familiar with ultrasound features of thyroid carcinoma, and expansion of the indications to FNA is not recommended. For patients with multiple nodules indicated by preoperative ultrasound or suspected to have multiple nodules during intraoperative exploration, or patients who present with high-risk factors, total thyroidectomy is recommended. Prophylactic central group lymph node dissection with intraoperative frozen pathology diagnosis is essential for surgeons to design a personalized surgical plan and postoperative therapy.