Postoperative Neck Ultrasonography Surveillance After Thyroidectomy in Patients With Medullary Thyroid Carcinoma: A Multicenter Study.

BACKGROUND: For detecting tumor recurrence of medullary thyroid carcinoma (MTC) in the neck, an appropriate frequency and interval of postoperative ultrasonography (US) surveillance remains unclear. This study aimed to assess an appropriate interval and frequency of postoperative neck US surveillance for detecting tumor recurrence in patients who had undergone thyroid surgery due to MTC. METHODS: A total of 86 patients who had undergone thyroid surgery for the treatment of MTC and had at least one postoperative US follow-up examination at any of nine affiliated hospitals were included. Postoperative follow-up US, clinical, and histopathological results of patients were reviewed. The tumor recurrence/persistence rate of MTC was investigated, and the interval and session number of postoperative follow-up US and clinicopathologic factors were compared between tumor recurrence/persistence and non-recurrence groups. RESULTS: Of the 86 patients, 22 (25.6%) showed tumor recurrence/persistence. Of the 22 patients with tumor recurrence/persistence, 11 (50%) showed structural recurrence/persistence in the neck on follow-up US. In these 11 patients, the mean interval and session number of postoperative follow-up US between initial surgery and the first US detection of recurrence/persistence was 41.3 ± 39.3 months (range, 6-128 months) and 2.6 ± 2.3 (range, 1-8), respectively. On follow-up US, 6 (54.5%, 6/11) were diagnosed with tumor recurrence/persistence within 3 years of the initial surgery. Tumor recurrence/persistence was significantly correlated with TNM stage (p < 0.001) and multiplicity/bilaterality (p = 0.013). CONCLUSION: For detecting MTC recurrence/persistence, postoperative US surveillance at 1-year intervals may be sufficient within the first 3 years after thyroid surgery, but depending on the presence of relevant risk factors, annual or biannual US surveillance may be recommendable for 4-10 years after thyroid surgery.

Analysis of postoperative ultrasonography surveillance after total thyroidectomy in patients with papillary thyroid carcinoma: a multicenter study.

Background In papillary thyroid carcinoma (PTC) patients, postoperative ultrasonography (US) surveillance is recommended at intervals of six or 12 months even though evidence is weak. Purpose To determine the optimal interval of postoperative US surveillance in patients after total thyroidectomy for the treatment of PTC using multicenter data. Material and Methods A total of 1400 patients from seven tertiary hospitals who underwent total thyroidectomy for treatment of PTC were included. Based on a retrospective review of clinical and pathologic results, multiple factors were analyzed according to recurrence/persistence or no recurrence/persistence. In recurrence/persistence group, the interval and number of follow-up US sessions in the initial detection of recurrence/persistence were investigated. Results Of the 1400 patients, 115 (8.2%) showed tumor recurrence/persistence on follow-up US. Of 115 recurrence/persistence cases, 89 (77.4%) were initially detected on US: nodal recurrence/persistence (n = 92), non-nodal recurrence/persistence (n = 22), and both (n = 1). Among the clinical and pathologic factors, only tumor size and N stage were significant predictors for recurrence/persistence. In the recurrence/persistence group, the mean interval and number of follow-up US sessions in the initial detection of recurrence/persistence was 22.3 ± 16.8 months and 2.2 ± 1.9, respectively. Approximately two-thirds of recurrence/persistence cases (76/115, 66.1%) were detected in follow-up US within two years after total thyroidectomy. Conclusion In PTC patients after total thyroidectomy, the optimal interval of the first US follow-up may be one to two years after thyroid surgery, and the appropriate number of postoperative US surveillance sessions within the first five years may be only one or two.

Factors influencing the outcome from ultrasonography-guided fine-needle aspiration of benign thyroid cysts and partially cystic thyroid nodules: A multicenter study.

PURPOSE: The effect of ultrasonography (US)-guided fine-needle aspiration (US-FNA) for the collapse of benign cystic thyroid nodules is still unclear. This study aimed to assess the positive response rate following US-FNA of the cystic component of thyroid cysts and of partially cystic thyroid nodules (PCTNs), and to evaluate the factors influencing the outcome. METHODS: From June to December 2013, seven radiologists at seven institutions prospectively performed US-FNA on 320 cystic thyroid nodules in 320 patients. Among them, 179 underwent at least one follow-up US examination following US-FNA of the cystic component at each institution by the same radiologist. A variety of factors, including US features of cystic thyroid nodules, the characteristics of the aspirates, and the follow-up US findings, were analyzed. RESULTS: Of 179 cystic thyroid nodules, there were 53 thyroid cysts and 126 PCTNs. Of 179 cystic thyroid nodules, no malignancies were detected. On follow-up US, the mean size reduction rate of the cystic component was 31.9%, and 102 out of 179 thyroid nodules (57.0%) were assigned to the response group. On univariate analysis, the degree of aspiration and time interval between US-FNA and the final follow-up US showed the significant differences between the response and no response groups. On multivariate analysis, the only factor that influenced the outcome was the nodule type. The cystic component's positive response rate after simple aspiration was higher in the thyroid cysts than in the PCTNs. CONCLUSIONS: US-FNA may be effective at collapsing the cystic components of benign thyroid cysts and PCTNs.

ANALYSIS OF POSTOPERATIVE ULTRASONOGRAPHY SURVEILLANCE AFTER HEMITHYROIDECTOMY IN PATIENTS WITH PAPILLARY THYROID MICROCARCINOMA: A MULTICENTER STUDY.

OBJECTIVE: The optimal follow-up interval for postoperative ultrasonography (US) surveillance after hemithyroidectomy in patients with papillary thyroid microcarcinoma (PTMC) is unclear. The purpose of this study was to evaluate the prevalence of tumor recurrence/persistence and to investigate the appropriateness of postoperative US surveillance in PTMC patients who underwent hemithyroidectomy. METHODS: Our institutional review board approved this retrospective study. From 2000 to 2011, 800 patients underwent hemithyroidectomy as treatment for PTMC, as well as at least one session of postoperative follow-up US, at four different institutions. The images and data of postoperative US surveillance were retrospectively investigated by experienced radiologists at each institution. Based on the follow-up US and histopathologic results, locoregional tumor recurrence/persistence was determined. RESULTS: Of the 800 patients, 82.2% had T1a, 17.8% had T3, and none had T1b, T2, T4a, or T4b disease; 6.9% had unknown N stage, 80.1% had N0, 13% had N1a, and none had N1b, based on histopathology. There were also no cases of distant metastasis after hemithyroidectomy. Among the patients, 784 (98%) showed no tumor recurrence/persistence, and 16 (2%) showed locoregional tumor recurrence/persistence during the follow-up period. The patients differed in the number of sessions and the intervals of postoperative follow-up US. In the 16 patients with tumor recurrence/persistence, the mean interval of postoperative follow-up US since the first US detection of tumor recurrence/persistence was 42.9 ± 25.9 months. All recurrence/persistence cases were subcentimeter. CONCLUSION: Postoperative US surveillance at 1-or 2-year intervals may be unnecessary because of the very low recurrence rate in PTMC. ABBREVIATIONS: EMR = electronic medical record; PTMC = papillary thyroid microcarcinoma; TNM = tumor, node, metastasis; US = ultrasonography; US-FNA = ultrasonography-guided fine-needle aspiration.

Differences between the clinical and histopathological tumor stages in breast cancer diagnosed using vacuum-assisted breast biopsy.

The present study aimed to determine the difference between the clinical tumor stage (T stage) based on pre-operative ultrasound and the histopathological T stage subsequent to surgery in vacuum-assisted breast biopsy (VABB)-diagnosed breast cancer. Tumor sizes measured ultrasonography (USG) and histologically were retrospectively calculated and analyzed using paired t-tests in 209 patients diagnosed with breast cancer using VABB. The patients were classified into two groups, consisting of breast imaging reporting and data system (BI-RADS) category 4a or below, who underwent complete resection by VABB, and BI-RADS category 4b or above, who underwent incisional biopsy by VABB. The histopathological tumor size was found to be smaller compared with the USG-determined size in 92.3% of pT1a, 75.5% of pT1b, 44.2% of pT1c, 47.7% of pT2 and 0% of pT3 cases. Furthermore, the histopathological tumor size was smaller compared with the USG-determined size in 62.8% of cases classified as BI-RADS category 3-4a and in 53.7% of cases classified as BI-RADS category 4b-5. The smaller the primary tumor at the time of diagnosis by VABB, the higher the likelihood of pathological underestimation on post-operative histopathological assessment compared to pre-operative USG.

Long-term follow-up result of benign phyllodes tumor of the breast diagnosed and excised by ultrasound-guided vacuum-assisted breast biopsy.

PURPOSE: Percutaneous removal of benign breast tumors using ultrasound-guided vacuum-assisted breast biopsy (VABB) has been recently regarded as a feasible and safe method without serious complications. The aim of this study was to evaluate the efficacy and safety of the VABB in the treatment of benign phyllodes tumors, and to identify whether or not surgical re-excision is necessary for benign phyllodes tumors diagnosed and excised by VABB. METHODS: From January 2003 to December 2011, a total of 6,923 VABB were performed in 5,434 patients. Out of 6,923 lesions, 53 were benign phyllodes tumors. Among these, 31 lesions, with a follow-up period of longer than 24 months, were enrolled in this study. Ultrasonography follow-up was performed at 3 to 6 month intervals in order to assess recurrence. The mean follow-up period was 75.9±13.5 months (range, 24-94 months). RESULTS: The mean patient age at presentation was 31.6±9.4 years. The mean size of the lesion was 1.60±0.88 cm. The majority of lesions, 74.2% (23 cases), were palpable, and 25.8% (8 cases) were non-palpable. Twenty-two lesions (71.0%) were classified as Breast Imaging Reporting and Data System category 3, and nine lesions (29.0%) were classified as category 4a, by ultrasonography. During the follow-up period, local recurrence developed in one lesion, making the local recurrence rate 3.2%. CONCLUSION: If a benign phyllodes tumor is diagnosed, and sufficiently excised by VABB, observing the clinical course may be considered as an alternative to performing immediate wide local excision; this is the case despite the fact that it would need to be observed for a prolonged period of time.

Symptomatic benign thyroid nodules: efficacy of additional radiofrequency ablation treatment session--prospective randomized study.

PURPOSE: To prospectively evaluate the efficacy of additional radiofrequency (RF) ablation by comparing the results of one and two sessions. MATERIALS AND METHODS: All patients gave written informed consent to participate in this institutional review board-approved prospective study. From September 2007 to February 2008, 30 patients with benign predominantly solid thyroid nodules causing pressure symptoms and/or cosmetic problems were randomly assigned to undergo single-session (group 1, n = 15) or two-session (group 2, n = 15) RF ablation. RF ablation was performed by using an 18-gauge internally cooled electrode with ultrasonographic guidance. Nodule volume and cosmetic and symptom scores were evaluated before ablation and at 1, 3, and 6 months after initial ablation, and quantitative comparisons of these were performed by using the Mann-Whitney and Wilcoxon signed rank tests; the Spearman rank test was used for correlation between nodule volume reduction and applied energy. RESULTS: At 6-month follow-up, there was significant nodule volume reduction, from 13.3 mL ± 12.9 (standard deviation) to 3.8 mL ± 4.4 in group 1 (P = .001), and from 13.0 mL ± 6.8 to 3.0 mL ± 2.2 in group 2 (P = .001). Each group showed significant improvement in cosmetic (P < .0001) and symptom (P = .001) scores. However, there was no significant difference in volume reduction, cosmetic score, and symptom score between two groups (P = .078, P > .99, and P = .259, respectively). In group 1, three of four patients who had a pretreatment nodule volume larger than 20 mL underwent additional RF ablation because of unresolved clinical problems after the first session. CONCLUSION: Single-session RF ablation showed significant volume reduction and satisfactory clinical response in most patients. Therefore, additional RF ablation should be limited to patients with a large nodule (>20 mL) or unresolved clinical problems.

Radiofrequency ablation of benign thyroid nodules and recurrent thyroid cancers: consensus statement and recommendations.

Thermal ablation using radiofrequency is a new, minimally invasive modality employed as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. The Task Force Committee of the Korean Society of Thyroid Radiology has developed recommendations for the optimal use of radiofrequency ablation for thyroid nodules. These recommendations are based on a comprehensive analysis of the current literature, the results of multicenter studies, and expert consensus.

Benign predominantly solid thyroid nodules: prospective study of efficacy of sonographically guided radiofrequency ablation versus control condition.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of radiofrequency ablation of benign predominantly solid thyroid nodules by comparing the findings in treatment and control groups. SUBJECTS AND METHODS: Thirty patients with normal thyroid function, each with a benign predominantly (> 50%) solid thyroid nodule causing pressure symptoms or cosmetic problems, were assigned to a control group (n = 15) or to a group undergoing a single session of radiofrequency ablation (n = 15). Thyroid nodule volume, thyroid function, pressure symptoms, and cosmetic concerns were evaluated before treatment and during follow-up. Sonographically guided radiofrequency ablation was performed with an internally cooled electrode (1-cm active tip) with an output power of 30-80 W. RESULTS: The control group had no resolution of symptoms or cosmetic problems. The mean nodule volume increased slightly after 6 months but without statistical significance (p = 0.46). In the radiofrequency ablation group, the mean symptom score (p = 0.001) and cosmetic grade (p = 0.001) improved significantly. Mean nodule volume decreased significantly from 7.5 +/- 4.9 mL (range, 1.7-20.0 mL) to 1.3 +/- 0.8 mL (range, 0.2-2.6 mL) 6 months after radiofrequency ablation (p = 0.001). There were no major complications of ablation. CONCLUSION: This study confirmed that radiofrequency ablation is effective for reducing nodule volume and relieving nodule-related clinical problems and that an effect due to spontaneous nodule reduction can be excluded owing to the results of the comparison with a similar control group.