Fine Needle Aspiration Cytology vs. Core Needle Biopsy for Thyroid Nodules:A Prospective, Experimental Study Using Surgical Specimen

Purpose@#To evaluate and compare the diagnostic outcomes of ultrasonography (US)-guided fine needle aspiration (FNA) and core needle biopsy (CNB) performed on the same thyroid nodule using a surgical specimen for direct comparison. @*Materials and Methods@#We included 89 thyroid nodules from 88 patients from February 2015 to January 2016. The inclusion criterion was thyroid nodules measuring ≥ 20 mm (mean size: 40.0 ± 15.3 mm). Immediately after surgical resection, FNA and subsequent CNB were performed on the surgical specimen under US guidance. FNA and CNB cytopathologic results on the specimen were compared with the surgical diagnosis. @*Results@#Among the 89 nodules, 30 were malignant and 59 were benign. Significantly higher inconclusive rates were seen in FNA for malignant than benign nodules (80.0% vs. 39.0%, p < 0.001). For CNB, conclusive and inconclusive rates did not differ between benign and malignant nodules (p = 0.796). Higher inconclusive rates were seen for FNA among cancers regardless of US features, and in the subgroup of size ≥ 40 mm (62.5% vs. 22.9%, p = 0.028). Eleven cancers were diagnosed with CNB (36.7%, 11/30), while none was diagnosed using FNA. @*Conclusion@#In this experimental study using surgical specimens, CNB showed a potential to provide improved diagnostic sensitivity for thyroid cancer, especially when a conclusive diagnosis is limited with FNA.

Comparisons Between Normocalcemic Primary Hyperparathyroidism and Typical Primary Hyperparathyroidism

Background@#Normocalcemic primary hyperparathyroidism (NPHPT) was first described in 2008. It is defined as consistently elevated serum parathyroid hormone (PTH) levels with normal serum calcium (sCa) concentration, after excluding secondary causes of PTH elevation. However, the exact definition and management strategy for NPHPT remain controversial. We retrospectively investigated the clinicopathological features and short-term outcomes of NPHPT patients. @*Methods@#A total of 280 patients who were surgically indicated for primary hyperparathyroidism (PHPT) at the Yonsei Severance Medical Center between 2015 and 2019 were included. Patients were classified according to preoperative PTH, corrected sCa, and ionized calcium (iCa) levels as follows: typical primary hyperparathyroidism (TPHPT, elevated PTH, sCa, and iCa, n = 158) and NPHPT (elevated PTH, normal sCa, n = 122). @*Results@#NPHPT was commonly seen in younger individuals (aged < 50 years, P = 0.025);nephrolithiasis and bone fractures were common. Preoperative PTH level was higher in the TPHPT group (P < 0.001). The NPHPT group had higher numbers of multiple parathyroid lesions (P = 0.004) that were smaller (P = 0.011). NPHPT patients were further divided into two subgroups according to iCa levels: the elevated (n = 95) and normal iCa (n = 27) groups. There was no significant difference between the two subgroups regarding symptoms and multiplicity of lesions. @*Conclusion@#We found that NPHPT may be a heterogeneous disease entity of PHPT with high rates of multi-gland disease, which appears to be biochemically milder but symptomatic.Intraoperative PTH monitoring might help increase the surgery success rate. Moreover, the short-term outcomes of NPHPT after surgery did not differ from that of TPHPT.

Cooperative Subtype Switch of Thyroid Hormone Receptor and Nuclear Receptor Corepressor Related Epithelial–Mesenchymal Transition in Papillary Thyroid Cancer

Background and Objectives@#Although thyroid hormones affect human cancer progression, the regulatory mechanism of thyroid hormone receptors in carcinogenesis has not been elucidated. This study aimed to evaluate the expression pattern of the thyroid hormone receptor (TR) and its corepressors, and to investigate the clinical and biological functions of TR. @*Materials and Methods@#Transcriptomic and clinical data for thyroid cancer were downloaded from The Cancer Genome Atlas. Paraffin-embedded tissue sections from patients who underwent thyroidectomy were used for immunohistochemistry. BCPAP cells were treated with T3 to investigate the thyroid hormone target genes. Thyroid hormone receptor alpha (THRA) and Thyroid hormone receptor beta (THRB) were knocked down by transient siRNA transfection. @*Results@#THRA and THRB expression was lower in thyroid cancer tissues than in normal tissues. However, strong focal staining of TRβ was observed in the invasive front. High THRB expression was associated with high Silencing Mediator for Retinoid or Thyroid hormone receptor (SMRT) expression, older age, a high MACIS (distant Metastasis, patient Age, Completeness of resection, local Invasion, and tumor Size) score, more aggressive histological subtypes, more frequent extra-thyroidal extension, and advanced TNM stage. THRB expression was positively correlated with Hypoxia Inducible Factor 1 Subunit Alpha (HIF1A), L1 Cell Adhesion Molecule (L1CAM), and Lysyl Oxidase (LOX) expression. Thyroid hormone-induced HIF1A, L1CAM, and LOX upregulation was abolished by siTHRB but not siTHRA in BCPAP cells. High SMRT and high THRB groups (SMRT/THRB) presented more aggressive clinical features and showed an upregulation of HIF1A, L1CAM, and LOX, as well as of epithelial-mesenchymal transition (EMT)-related genes, causing changes in the tumor microenvironment. @*Conclusion@#Cooperative subtype switching from NCOR1/THRA to SMRT/THRB was thus related to aggressive clinical and molecular features, possibly related to EMT and EMT-related tumor microenvironment.

Lactate Dehydrogenase A as a Potential New Biomarker for Thyroid Cancer

Background@#Several cancers show increased levels of lactate dehydrogenase A (LDHA), which are associated with cancer progression. However, it remains unclear whether LDHA levels are associated with papillary thyroid cancer (PTC) aggressiveness or with the presence of the PTC prognostic marker, the BRAFV600E mutation. This study aimed to evaluate the potential of LDHA as a PTC prognostic marker. @*Methods@#LDHA expression was examined in 83 PTC tissue specimens by immunohistochemistry. Human thyroid cell lines were genetically manipulated to overexpress BRAFV600E or were treated with a BRAF-specific short hairpin RNA (shBRAF), whose effects on LDHA expression were evaluated by Western blotting. Data from 465 PTC patients were obtained from The Cancer Genome Atlas (TCGA) database and analyzed to validate the in vitro results. @*Results@#LDHA was aberrantly overexpressed in PTC. Intense immunostaining for LDHA was observed in PTC specimens carrying mutated BRAF, whereas the intensity was less in wild-type BRAF samples. Overexpression of BRAFV600E resulted in LDHA upregulation, whereas treatment with shBRAF downregulated LDHA in human thyroid cell lines. Furthermore, LDHA mRNA expression was significantly elevated and associated with BRAFV600E expression in thyroid cancer tissues from TCGA database. Additionally, LDHA overexpression was found to be correlated with aggressive clinical features of PTC, such as lymph node metastases and advanced tumor stages. @*Conclusion@#LDHA overexpression is associated with the BRAFV600E mutation and an aggressive PTC behavior. Therefore, LDHA may serve as a biomarker and therapeutic target in PTC.

Liver X Receptor β Related to Tumor Progression and Ribosome Gene Expression in Papillary Thyroid Cancer

Background@#Intracellular lipid deposition has been reported in thyroid glands in obese animal and human. To understand the regulatory mechanism of lipid metabolism in thyroid cancer, we investigated the expression status of liver X receptor (LXR) and analyzed its clinicopathological characteristics and molecular biological features. @*Methods@#Expression status of LXR and its transcriptional targets in human cancers were analyzed using The Cancer Genome Atlas (TCGA). The gene-sets related to high LXRβ expression was investigated by gene set enrichment analysis (GSEA) using Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathways and gene ontology biologic process. Quantitative reverse transcription polymerase chain reaction was performed in thyroid cancer samples using our validation cohort. @*Results@#In contrast to low expression of LXRα, LXRβ was highly expressed in thyroid cancer compared to the other types of human cancers. High LXRβ expression was correlated with the expression of LXRβ transcriptional targets genes, such as apolipoprotein C1 (APOC1), APOC2, apolipoprotein E (APOE), ATP binding cassette subfamily G member 8 (ABCG8), sterol regulatory elementbinding protein 1c (SREBP1c), and SPOT14. Furthermore, High LXRβ expression group indicated poor clinicopathological characteristics and aggressive molecular biological features independently from the drive mutation status. Mechanistically, high LXRβ expression was coordinately related to ribosome-related gene sets. @*Conclusion@#The mechanistic link between LXRβ and ribosomal activity will be addressed to develop new diagnostic and therapeutic targets in thyroid cancers.

Long-term outcomes of abdominal paraganglioma

Purpose@#Paragangliomas (PGL) are rare neuroendocrine tumors derived from chromaffin cells of the autonomic nervous system. We aim to describe our experience and the long-term outcome of abdominal PGL over the last decade. @*Methods@#A retrospective review of patients diagnosed with PGL in our hospital between November 2005 and June 2017 was conducted. All nonabdominal PGL were excluded and the clinicopathological features and long-term outcomes of the patients were analyzed. @*Results@#A total of 46 patients were diagnosed with abdominal PGL. The average age of diagnosis was 55.4 years and there was no sex predilection. The average tumor size was 5.85 cm and they were predominantly located in the infrarenal position (50%). The mean follow-up period was 42 months (range, 1.8–252 months). All patients with metastases had Pheochromocytoma of the Adrenal Gland Scaled Score (PASS) of ≥4. One patient presented with synchronous metastases while 2 developed local recurrence and distant metastases. One presented with only local recurrence. One patient died 5 years after diagnosis. @*Conclusion@#Abdominal PGL is a rare tumor with excellent long-term prognosis. Recurrence although uncommon, can occur decades after initial diagnosis. Long-term follow-up is therefore recommended for all patients with PGL, especially in patients with PASS of ≥4.

Surgical outcomes of laparoscopic adrenalectomy for primary hyperaldosteronism: 20 years of experience in a single institution

PURPOSE: Recently, posterior retroperitoneoscopic adrenalectomy (PRA) has been reported to have some advantages over laparoscopic transperitoneal adrenalectomy (LTA). The objectives of this study were to report our experience over 12 years with laparoscopic adrenalectomy for primary hyperaldosteronism (PHA) and to examine surgical outcomes of PRA compared with LTA in patients with PHA. METHODS: The medical records of 527 patients who underwent minimally invasive adrenalectomy, including LTA or PRA, from January 2006 until May 2017 were reviewed at Severance Hospital (Seoul, Korea). Clinicopathologic characteristics and surgical outcomes of 146 patients with PHA who underwent LTA (19 patients) or PRA (127 patients) were analyzed retrospectively by complete chart review. RESULTS: The overall rates of biochemical and clinical cure were 91.1% and 93.1%, respectively. The mean operation time of the PRA group was significantly shorter than that of the LTA group (72.3 ± 24.1 minutes vs. 115.7 ± 69.7 minutes, P = 0.015). The length of hospital stay in the PRA group was significantly shorter than in the LTA group (3.5 ± 1.3 days vs. 4.2 ± 1.6 days, P = 0.029), and the first meal after surgery came earlier in the PRA group (0.3 ± 0.5 days vs. 0.6 ± 0.5 days, P = 0.049). The number of pain-killers used was also significantly smaller in the PRA group (2.3 ± 2.1 vs. 4.3 ± 2.3, P < 0.001). CONCLUSION: PRA offers an alternative or likely superior method for treatment of small adrenal diseases such as PHA, with improved surgical outcomes.

Usefulness of dynamic risk stratification in pediatric patients with differentiated thyroid carcinoma

PURPOSE: Recently, the American Thyroid Association (ATA) dynamic risk stratification (DRS) has been verified to be more valuable than the static anatomical staging system for predicting prognosis in patients with differentiated thyroid carcinoma (DTC). The purpose of this retrospective study was to compare the clinical usefulness of DRS, which is based on the response to initial treatment, with that of ATA initial risk stratification in pediatric patients. METHODS: A total of 144 pediatric patients underwent thyroid operation from August 1982 to December 2013 at Yonsei University Hospital (Seoul, Korea). Among them, 128 patients with complete clinical data were enrolled in this study. Clinicopathologic features and surgical outcomes were retrospectively analyzed by medical chart review. The mean follow-up duration was 11.5 years. RESULTS: The mean tumor size was 2.1 cm; 80.4% of patients were diagnosed with conventional papillary thyroid carcinoma, and 7.0% of patients were diagnosed with follicular thyroid carcinoma. Low-risk patients had the highest probability of an excellent response to initial treatment (66.6%). High-risk patients had the highest probability of a structural incomplete response (100%) and the lowest probability of an excellent response (11.1%). The ATA risk stratification and the DRS system were independent risk factors for disease-free survival (DFS) (P = 0.041 and P < 0.001, respectively). CONCLUSION: The DRS system, which is based on the response to initial treatment, can offer more useful prognostic information compared with ATA risk stratification in pediatric patients with DTC.

Is familial papillary thyroid microcarcinoma more aggressive than sporadic form?

PURPOSE: With the increasing incidence of papillary thyroid microcarcinoma (PTMC), familial papillary thyroid microcarcinoma (FPTMC) is now recognized more frequently. However, the biological behavior of FPTMC is poorly understood. The aim of this study was to investigate the prevalence of FPTMC and its biological aggressiveness. METHODS: Between March 2006 and July 2010, 2,414 patients underwent primary surgical therapy for PTMC and 149 (6.2%) were further classified as FPTMC. To determine the biological aggressiveness of FPTMC, we compared the clinicopathological features and prognosis between FPTMC and sporadic PTMC (SPTMC). RESULTS: The male-to-female ratio was higher in FPTMC than in sporadic papillary thyroid microcarcinoma (SPTMC: 1:4.5 vs. 1:7.2, P = 0.041). The central lymph node (LN) metastasis rate was significantly higher in FPTMC than in SPTMC (36.2% vs. 24.2%, P = 0.002). The local recurrence rate was also higher in FPTMC than in SPTMC (4.5% vs. 0.6%, P < 0.001). We identified familial occurrence in 6.2% of cases of PTMC. FPTMC is associated with a high rate of central LN metastasis and local recurrence. CONCLUSION: These findings suggest that close follow-up can be beneficial in FPTMC patients to detect local recurrence.

Risk Factors of Postoperative Hypocalcemia after Total Thyroidectomy of Papillary Thyroid Carcinoma Patients / 대한내분비외과학회지

PURPOSE: Postoperative hypocalcemia is a common complication of thyroidectomy. This study evaluated the incidence and predisposing risk factors for postoperative permanent hypocalcemia after total thyroidectomy. METHODS: There were 1,247 consecutive patients undergoing total thyroidectomy and complete treatment and observation for differentiated thyroid cancer between January 2012 to December 2012 who were enrolled in this study. Patients were divided into two groups, those remaining normalcalcemic (Group I-824 pts) and those who had hypocalcemia requiring treatment (Groups II-423 pts). Group II was subdivided into a transient hypocalcemic group (Group IIA-409 pts) and a permanent hypocalcemic group (Group IIB-14 pts). RESULTS: Female gender, thyroiditis, preserved parathyroid number, lateral lymph node metastasis, RAI treatment, preoperative parathyroid hormone and preoperative vitamin D were significantly associated with the development of postoperative hypocalcemia by multivariate analysis. Comparing patients with transient versus permanent hypocalcemia, tumor size and multiplicity were significantly related to the development of permanent hypocalcemia by multivariate analysis. RAI treatment and parathyroid hormone level on the postoperative third day were significantly related to recovery from transient hypocalcemia to normo-calcemia. CONCLUSION: Risk factors of postoperative hypocalcemia were associated with preoperative patient factors and advanced thyroid cancer. Advanced thyroid cancer was a risk factor for permanent hypocalcemia. To prevent postoperative hypocalcemia, we should focus on patient condition and need to preserve parathyroid gland more carefully in thyroid surgery.

Medullary thyroid carcinoma: a 30-year experience at one institution in Korea

PURPOSE: The objective of this study was to review the clinical outcome and prognosis of patients with sporadic and hereditary medullary thyroid cancer (MTC) who were treated at a single tertiary hospital in Korea. METHODS: We retrospectively reviewed the case files of 85 patients treated from August 1982 to February 2012. RESULTS: In all, 65 patients (76.5%) had sporadic MTC and 20 patients (23.5%) had hereditary MTC. Patients in the sporadic group were older than in the hereditary group (P < 0.001). However, the hereditary group had more tumor multiplicity (P < 0.001) and bilaterality (P < 0.001). Neither survival rate was significantly different between the sporadic and hereditary groups (P = 0.775 and P = 0.866). By multivariate analysis, distant metastasis was a significant prognostic factor for overall and progression-free survival. CONCLUSION: In general, patients with MTC have favorable outcomes. Distant metastasis appears to be the strongest predictor of overall and progression-free survival.

Quality of Life Outcomes after Robotic Thyroid Surgery / 대한갑상선학회지

The robotic approach is the new frontier of thyroid cancer surgery, with several advantages over conventional open and endoscopic techniques. Recent assessments of quality of life (QoL) outcomes have found that patients undergoing robotic thyroid surgery using transaxillary approach experience lower levels of dissatisfaction and regret than patients undergoing conventional open thyroid surgery, largely due to differences in cosmetic outcomes. Prospective trials evaluating functional parameters, including pain, neck discomfort, and sensory changes in the neck, have favored robotic over conventional open thyroid surgery. Similarly, objective and subjective evaluations of voice and swallowing discomfort were improved in patients undergoing robotic thyroidectomy. Thus, use of a robot results in overall increases in cosmetic satisfaction and decreases in several measures of postoperative discomfort compared with the conventional open thyroid technique. However, a proper evaluation of QoL requires long-term assessments, and randomized controlled trials are necessary to definitively establish the real benefits of robotic surgery. This review provides merits and demerits of robotic thyroidectomy and radical neck dissection, based on published data, as well as comparing QoL outcomes after robotic and conventional open thyroidectomy.

Molecular Testing in Diagnosis of Thyroid Cancer / 대한내분비외과학회지

With increasing prevalence of thyroid nodules, clinicians are increasingly impelled to identify the optimal predictor of thyroid cancer, with the goal of guiding management based on assessed risk. Fine-needle aspiration cytology is the gold standard diagnostic method for thyroid nodules. However, fine-needle aspiration cytology is not perfect and adjuncts which might complement its predictive value are being investigated from several innovative perspectives. For these vigorous efforts, remarkable advances have been achieved in understanding several major biologic areas of thyroid cancer, including the molecular alterations for loss of radioiodine avidity of thyroid cancer, the pathogenic role of the MAP kinase and PI3K/Akt pathways and their related genetic alterations in thyroid tumorigenesis and pathogenesis. These exciting advances provide unprecedented opportunities for development of molecular-based novel diagnostic and therapeutic strategies for thyroid cancer. The common somatic genetic changes in thyroid cancer of follicular cell origin (RET/PTC, NTRK, RAS, BRAF, PAX8-PPARgamma) are generally mutually exclusive, with distinct genotype-histologic subtype associations of thyroid cancer. Mutation analysis in fine needle aspiration samples has been applied to improve the diagnostic accuracy. In studies regarding gene expression profiling, aberrant gene methylation and miRNA have shown significant progress toward identification of biomarkers that could improve the accuracy of fine needle aspiration cytology in the evaluation of patients with thyroid nodule and prediction of disease aggressiveness. Future clinical trials evaluating the accuracy and cost-effectiveness of applying these biomarkers in the management of thyroid neoplasm should be considered.

The usefulness and accuracy of sentinel lymph node biopsy using single photon emission computed tomography/computed tomography with 99mTc phytate to detect locoregional lymph node metastases in patients with papillary thyroid carcinoma / 대한외과학회지

PURPOSE: Regional lymph node (LN) metastases are detected in 57-85% of patients with papillary thyroid carcinoma (PTC) and are associated with increased tumor recurrence. However, the management of lymphatic disease in patients with PTC has been ongoing source of debate. We have prospectively assessed the usefulness and accuracy of sentinel LN (SLN) biopsy for the detection of LN metastases in patients with PTC on preoperative imaging using single photon emission computed tomography/computed tomography (SPECT/CT) and 99mTc phytate. METHODS: We prospectively assessed 39 patients with PTC who had risk factors for recurrence or with the necessity of intraoperative LN sampling for suspicious LN metastases on preoperative imaging from August 2010 to March 2011. The patients underwent preoperative lymphoscintigraphy and SPETC/CT and intraoperative SLN biopsy (SLNB). RESULTS: 99mTc lymphoscintigraphy and SPECT/CT localized SLN in 38 patients (97.4%), with the gamma probe identifying 2.15 mean SLNs in the lateral neck of the 39 patients. Skip metastasis was found in one patient, and lateral compartment LN metastasis in 17 (43.5%). The sensitivity, specificity, and accuracy of SLNB for lateral compartment LN metastasis were 88.2%, 100%, and 94.8%, respectively. SLNB was more accurate and useful for lateral than for central compartment LN metastasis. CONCLUSION: SPECT/CT improved SLN detection and anatomical localization compared with lymphoscintigraphy. SLNB in patients with risk factors for recurrence or the necessity of intraoperative LN sampling for suspected LN metastases on preoperative imaging was accurate in detecting LN metastases and may help in deciding whether to perform lateral compartment dissection in patients with PTC.

Effectiveness of 124I-PET/CT and 18F-FDG-PET/CT for Localizing Recurrence in Patients with Differentiated Thyroid Carcinoma

Although the prognosis of patients with differentiated thyroid carcinoma (DTC) is generally encouraging, a diagnostic dilemma is posed when an increasing level of serum thyroglobulin (Tg) is noted, without detection of a recurrent tumor using conventional imaging tools such as the iodine-131 whole-body scanning (the [131I] scan) or neck ultrasonography (US). The objective of the present study was to evaluate the diagnostic value of [124I]-PET/CT and [18F]-FDG-PET/CT in terms of accurate detection of both iodine- and non-iodine-avid recurrence, compared with that of conventional imaging such as the [131I] scan or neck ultrasonography (US). Between July 2009 and June 2010, we prospectively studied 19 DTC patients with elevated thyroglobulin levels but who do not show pathological lesions when conventional imaging modalities are used. All involved patients had undergone total thyroidectomy and radioiodine (RI) treatment, and who had been followed-up for a mean of 13 months (range, 6-21 months) after the last RI session. Combined [18F]-FDG-PET/CT and [124I]-PET/CT data were evaluated for detecting recurrent DTC lesions in study patients and compared with those of other radiological and/or cytological investigations. Nine of 19 patients (47.4%) showed pathological [18F]-FDG (5/19, 26.3%) or [124I]-PET (4/19, 21.1%) uptake, and were classed as true-positives. Among such patients, disease management was modified in six (66.7%) and disease was restaged in seven (77.8%). In particular, the use of the described imaging combination optimized planning of surgical resection to deal with locoregional recurrence in 21.1% (4/19) of patients, who were shown to be disease-free during follow-up after surgery. Our results indicate that combination of [18F]-FDG-PET/CT and [124I]-PET/CT affords a valuable diagnostic method that can be used to make therapeutic decisions in patients with DTC who are tumor-free on conventional imaging studies but who have high Tg levels.

Predictors of Resolution of Hypertension after Adrenalectomy in Patients with Aldosterone-producing Adenoma

Primary aldosteronism (PA) is a frequent cause of secondary hypertension and is amenable to surgical intervention when it is caused by aldosterone-producing adenoma (APA). Many patients, however, continue to require antihypertensive medications to control their blood pressure after adrenalectomy. The aim of this study was to determine the preoperative factors that predict clinical outcomes after adrenalectomy in patients with APA. We studied 27 patients (mean age 45+/-4 yr) who had APA and underwent unilateral adrenalectomy between December 1995 and September 2008 at our institution. Clinical and biochemical data were evaluated at baseline and after a mean follow-up of 51.8+/-47.0 months (range, 6-159). At the end of the follow-up, 16 patients (59.3%) were considered to experience "complete resolution" without postoperative medications, whereas 7 patients (25.9%) "improved" with medications and 4 patients (14.8%) were "uncontrolled." Three factors (< or =2 antihypertensive medications [P=0.007], duration of hypertension <6 yr [P=0.002], and serum aldosterone <350 pg/mL [P<0.001]) were the predictive for complete resolution in univariate analysis. Multivariate regression analysis showed that serum aldosterone level (<350 pg/mL) was the single most important factor that predicted complete resolution after surgery (P<0.001). The best preoperative clinical factor that predicted resolution of postoperative hypertension after adrenalectomy is serum aldosterone level (<350 pg/mL).

Initial Experience Using Gasless Transaxillary Robotic Thyroidectomy by a Single Surgeon / 대한내분비외과학회지

PURPOSE: Various endoscopic thyroidectomy procedures have been designed to minimize visible cervical scarring. However, endoscopic thyroidectomy is a technically challenging procedure that is performed by a limited surgeon. Robotic systems aida surgeon in performing minimally invasive head and neck surgery by offering superior visualization and dexterity. This study reports the initial experience of one surgeon with robotic thyroidectomy to assess the technical feasibility and safety of the approach. METHODS: One hundred four thyroid cancer patients (97 females, 7 males; mean age of 39.8±8.1 years) underwent robotic thyroidectomy using gasless transaxillary approach between November 2008 and October 2009 in Ajou University Hospital. All the procedures were completed successfully using the da Vinci surgical system without open conversion. Patient characteristics, postoperative clinical results, complications, and pathologic details were assessed. RESULTS: Total thyroidectomy was performed in 25 (24.0%) patients, subtotal thyroidectomy in 13 (12.5%) patients, and unilateral lobectomy in 66 (63.5%) patients. All patients underwent ipsilateral central compartment neck dissection, and two patients underwent selective lymph node (LN) dissection. The mean operation time was 134.5±47.2 min (range 61~310 min), in which the actual time for the thyroidectomy with lymphadenectomy (console time) was 56.4 min. (range 31~270). The mean number of LN resected was 3.9 (range 0~28). There were no serious complications. The mean hospital stay was 2.9±0.9 days (range 2~7). CONCLUSION: Robotic thyroidectomy is a feasible, safe, and cosmetically excellent procedure. The application of robotic technology for thyroid surgeries could be an alternative to endoscopic or conventional open thyroidectomy.

Follicular Thyroid Carcinoma: Clinicopathologic Features, Prognostic Factors, and Treatment Strategy

PURPOSE: Follicular thyroid carcinoma (FTC) is a relatively rare form of thyroid carcinoma that often presents at a more advanced stage of disease with a higher incidence of distant metastases because of its propensity for vascular invasion. However, FTC and papillary thyroid carcinoma (PTC) have similar prognoses when they are matched for age and stage. Therefore, this study was conducted to evaluate the useful prognostic factors and determine the optimal management of FTC. METHODS: This study was conducted on 216 patients with FTC who underwent thyroidectomy at our institutions between April 1986 and August 2006. The patients included 174 women and 42 men with a mean age of 41 (4~87) years, and patients underwent follow-up evaluation for a mean period of 114 (6~253) months. The potential risk factors for treatment outcome were calculated using multivariate analysis, and the prognostic accuracy of UICC/AJCC pTNM staging, AMES, AGES, MACIS, and Degroot classification for predicting survival were compared. RESULTS: During the follow-up period, 13 (6.0%) patients developed locoregional recurrences and 8 patients (3.7%) showed distant metastases. In addition, cause specific mortality was seen in 8 patients (3.7%). The overall survival and cause-specific survival (CSS) rates at 10 years were 95.4% and 89.3%, respectively, and these cases were accurately predicted by the AMES and pTNM staging systems. The Cox proportional hazards revealed that gender (P=0.015), angioinvasion (P=0.013), invasion to adjacent structure (P=0.003), widely invasive carcinoma (P=0.028), and distant metastases at the time of presentation (P<0.001) were independent prognostic factors for survival. CONCLUSION: The extent of surgery in cases of FTC should be individualized based on the clinicopathologic findings; Conservative surgery should be adequate for cases of minimally invasive FTC without angioinvasion, however total or near-total thyroidectomy should be conducted in cases of widely invasive and minimally invasive FTC with angioinvasion.

The Bone Mineral Density and Bone Metabolism of Patients with Differentiated Thyroid Carcinoma and who are Receiving Long-term TSH Suppressive Therapy / 대한내분비외과학회지

PURPOSE: The clinical implications of long-term suppressive thyroxine (TSH) therapy on the skeletal system are critical, largely because of the favorable prognosis of differentiated thyroid carcinomas (DTC). However, the potentialdeleterious effects of TSH suppressive therapy on the bone metabolism remain controversial. The aim of this prospective study was to assess the effects of chronic L-thyroxine (LT4) treatment with supraphysiologic doses of TSH on the bone mineral density (BMD) and biochemical bone remodeling markers. METHODS: This cross-sectional study was designed to compare patients with DTC and who were treated with LT4 for more than 2 years after thyroidectomy with an age-matched and gender-matched healthy control group. A total of 100 female outpatients (mean age: 47.5±13.8; 38 pre and 62 post-menopausal) who were on LT4 for between 2 and 10 yearswere enrolled. One hundred and three age-matched healthy volunteers were recruited as a control group. Laboratory tests were performed to exclude other possible factors for secondary osteoporosis. We measured the BMD by dual energy X-ray absorptiometry (DEXA), and bone turnover was assessed by several biochemical parameters. RESULTS: Our data showed no significant difference between the bone markers for the study group and the control group that had a premenopausal status. However, for the patients with a postmenopausal status, the serum levels of bone alkaline phosphatase were significant higher in the study group than that in the control group (P=0.038). We also found no significant difference between the study patients and the age- and weight-matched controls for the BMD at any site of measurement. CONCLUSION: This preliminary report suggests that bone turnover and accelerated bone loss might be related to the long-standing TSH suppression in postmenopausal women. Future prospective studies with an increased number of studied patients and a prolonged time of observation will be necessary in order to better assess the relative risk of osteoporosis in patients who are undergoing TSH suppressive treatment.

Clinicopathologic Features and Treatment Outcomes in Differentiated Thyroid Carcinoma Patients with Concurrent Graves' Disease

The clinical behaviors and treatment outcomes of thyroid carcinomas in patients with Graves' disease is a matter of controversy. This study aimed to identify the clinicopathologic features, treatment outcome, and the indicators for predicting recurrence, and to suggest the optimal extent of surgery in these patients. We retrospectively analyzed data of 58 patients who underwent surgical treatment for differentiated thyroid cancer and concurrent Graves' disease. The follow-up period ranged from 23 to 260 months (mean+/-standard devuation, 116.8+/-54.0). In our series, the mean age was 40.8+/-12.7 yr (range, 15-70), with a male-to-female ratio of 1: 6.25. The mean tumor size was 13+/-9 mm (range, 3-62). The surgical methods included 19 cases of total thyroidectomy, 38 cases of subtotal thyroidectomy, and 1 case of completion total thyroidectomy. Locoregional recurrence occurred in four patients (6.9%). The 10-yr overall survival and disease-free survival of patients were 95.8% and 91.1%, respectively. Age over 45 yr (p=0.031), tumor size over 10 mm (p=0.049), multiplicity (p=0.007), extracapsular invasion (p=0.021), and clinical cancer (p=0.035) were significantly more prevalent in patients with locoregional recurrence than in those without recurrence. We recommend that Graves' disease patients should undergo regular ultrasonography screening for early detection of thyroid carcinoma. We also suggest that the choice of extent of surgery should depend on the diagnostic timing (clinical or incidental) and factors for predicting recurrence.