LAUSR

This study aimed to assess the prevalence of tumor recurrence/persistence and determine the appropriate frequency and interval of follow-up neck ultrasonography (US) in papillary thyroid microcarcinoma (PTMC) patients who underwent hemithyroidectomy and long-term follow-up US. From January 2005 to December 2006, 179 patients underwent a hemithyroidectomy for the treatment of PTMC and at least 1 postoperative US surveillances. The postoperative follow-up US was performed by 2 radiologists for all patients. Based on the US and histopathologic results, tumor recurrence/persistence was determined. Of the 179 patients, the following results were determined after hemithyroidectomy: all patients exhibited T1 stage, while nodal metastasis to the ipsilateral level VI node (n = 27) and ipsilateral multifocality (n = 16) were found. Tumor recurrence was found in 5 (2.8%) of 179 and tumor persistence in 2 (1.1%) of 179. In the tumor recurrence cases, all patients underwent US-guided fine-needle aspiration for the newly detected thyroid nodule because of suspicious features on postoperative follow-up US (8-, 24-, 36-, 87-, and 96-month intervals). Differences were observed in the number of follow-up US sessions (mean, 5.2; range, 1-13) and in the interval period to the last follow-up (mean, 80.7 months; range, 8-138 months). Among the patients, 82 (45.8%) had a more than 120-month interval to the last follow-up US after hemithyroidectomy. In conclusion, the PTMC tumor recurrence rate was low, indicating that only 1 or 2 sessions of postoperative US follow-up may be sufficient to detect tumor recurrence within the first 10 years after hemithyroidectomy in PTMC patients.