Jong Ho Yoon

Gasless endoscopic thyroidectomy via an axillary approach: experience of 30 cases.

Surgery for thyroid disease requires skin incisions that can result in postsurgical problems such as prominent scars, adhesions, hypesthesia, and paresthesia in the neck. To overcome these problems we performed gasless endoscopic thyroidectomy via an axillary approach. Between May 2004 and April 200

Change of serum antithyroglobulin antibody levels is useful for prediction of clinical recurrence in thyroglobulin-negative patients with differentiated thyroid carcinoma.

OBJECTIVESnThe aim of the study was to evaluate the usefulness of the antithyroglobulin autoantibody (TgAb) value at 6-12 months after remnant ablation in predicting recurrence in differentiated thyroid carcinoma patients who had undetectable thyroglobulin (Tg) values. The change in TgAb concentration measured between the time of remnant ablation (TgAb1) and 6-12 months thereafter (TgAb2) was also evaluated as a possible prognostic indicator.nnnPATIENTS AND METHODSnPatients with differentiated thyroid carcinoma who underwent total thyroidectomy followed by (131)I remnant ablation between 1995 and 2003 at the Asan Medical Center (Seoul, Korea) were enrolled. Of these, 824 patients with undetectable Tg at 6-12 months after remnant ablation during thyroid hormone withdrawal were the subjects of this study.nnnRESULTSnTgAb2 was positive in 56 patients. Ten of 56 patients (18%) with positive TgAb2 had recurrence, whereas only 10 of 768 patients (1%) with negative TgAb2 had recurrence during 73.6 months of follow-up (P < 0.001). The change between TgAb1 and TgAb2 levels was evaluated in patients with positive TgAb2. TgAb concentration decreased by more than 50% in 21 patients (group 1) and by less than 50% in 16 patients (group 2), and it increased in 19 patients (group 3). The recurrence rates in groups 1, 2, and 3 were 0, 19, and 37%, respectively (P = 0.016).nnnCONCLUSIONSnSerum TgAb levels measured at 6-12 months after remnant ablation could predict recurrence in patients with undetectable Tg values. In patients with undetectable Tg and positive TgAb values, a change in TgAb concentration during the early postoperative period may be a prognostic indicator of recurrence.

Thyroid nodules with initially non-diagnostic, fine-needle aspiration results: comparison of core-needle biopsy and repeated fine-needle aspiration.

AbstractObjectiveTo evaluate the role of core-needle biopsy (CNB) by comparing the results of CNB and repeated fine-needle aspiration (FNA) for thyroid nodules with initially non-diagnostic FNA results.MethodsFrom October 2008 to December 2011, 360 nodules – 180 consecutive repeated FNAs and 180 consecutive CNBs –– from 360 patients (83 men, 277 women; mean age, 54.4xa0years) with initially non-diagnostic FNA results were analyzed retrospectively. The incidence of non-diagnostic results, inconclusive results, diagnostic surgery, and diagnostic performance of repeated FNA and CNB were assessed, and factors affecting second non-diagnostic results were evaluated.ResultsCNB achieved a significantly lower non-diagnostic and inconclusive rate than repeated FNA (1.1xa0% versus 40.0xa0%, Pu2009<u20090.001; 7.2xa0% versus 72.0xa0%, Pu2009<u20090.001). All diagnostic performances with CNB were higher than repeated FNA. The diagnostic surgery rate was lower with CNB than with repeated FNA (3.6xa0% versus 16.7xa0%, Pu2009=u20090.047). Multivariate logistic regression analysis showed that repeated FNA was the most important factor for second non-diagnostic results (ORu2009=u200956.06, Pu2009<u20090.001), followed by nodules with rim calcification (ORu2009=u20097.46, Pu2009=u20090.003).ConclusionsCNB is more useful than repeated FNA for reducing the number of non-diagnostic and inconclusive results and for preventing unnecessary diagnostic surgery for thyroid nodules with initially non-diagnostic FNA results.Key Points• Core-needle biopsy achieved a lower number of non-diagnostic and inconclusive results.n • Core-needle biopsy achieved better diagnostic performance.n • Use of core-needle biopsy could prevent unnecessary diagnostic surgery.n • Repeated fine-needle aspiration was significantly associated with a second non-diagnosis.

The prognostic value of the metastatic lymph node ratio and maximal metastatic tumor size in pathological N1a papillary thyroid carcinoma

OBJECTIVEnThe presence of central neck lymph node (LN) metastases (defined as pN1a according to Tumor Node Metastasis classification) in papillary thyroid cancer (PTC) is known as an independent risk factor for recurrence. Extent of LN metastasis and the completeness of removal of metastatic LN must have an impact on prognosis but they are not easy to measure. Moreover, the significance of the size of metastatic tumors in LNs has not been clarified. This study was to evaluate the impact of the extent of LN metastasis and size of metastatic tumors on the recurrence in pathological N1a PTC.nnnDESIGNnThis retrospective observational cohort study enrolled 292 PTC patients who underwent total thyroidectomy with central neck dissection from 1999 to 2005. LN ratio was defined as the number of metastatic LNs divided by the number of removed LNs, which was regarded as variable reflecting both extent of LN metastasis and completeness of resection, and LN size as the maximal diameter of tumor in metastatic LN.nnnRESULTSnThe significant risk factors for recurrence in univariate analysis were large primary tumor size (defined as larger than 2 cm), high LN ratio (defined as higher than 0.4), and presence of macrometastasis (defined as larger than 0.2 cm). Age, sex, clinical node status, and microscopic perithyroidal extension had no effect on recurrence. In multivariate analysis, high LN ratio and presence of macrometastasis were independent risk factors for recurrence.nnnCONCLUSIONnLN ratio and size of metastatic nodes had a significant prognostic value in pathological N1a PTC. We suggest that risk stratification of pathological N1a PTC according to the pattern of LN metastasis such as LN ratio and size would give valuable information to clinicians.

Empiric High-Dose 131-Iodine Therapy Lacks Efficacy for Treated Papillary Thyroid Cancer Patients with Detectable Serum Thyroglobulin, but Negative Cervical Sonography and 18F-Fluorodeoxyglucose Positron Emission Tomography Scan

CONTEXTnSome patients with elevated serum thyroglobulin (Tg) but a negative diagnostic whole body scan (WBS) after initial therapy for differentiated thyroid carcinoma may benefit from empirical radioactive iodine (RAI) therapy. However, previous studies enrolled patients with negative diagnostic WBS, regardless of neck ultrasonography (USG) and/or (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET), which have become the preferred diagnostic procedures in such patients.nnnOBJECTIVEnThe aim of this study was to evaluate the usefulness of empirical RAI therapy in patients with elevated stimulated Tg level and negative USG/FDG-PET findings after initial therapy for papillary thyroid carcinoma (PTC).nnnDESIGNnThis comparative study enrolled 39 patients with elevated stimulated Tg, negative diagnostic WBS, and negative USG/FDG-PET 1 yr after initial treatment. Empirical RAI therapy was performed in 14 patients (treatment group), whereas 25 patients were followed up without therapy (control group).nnnRESULTSnThere was no significant between-group difference in basal clinicopathological parameters. None of the 14 patients in the treatment group showed iodine uptake on posttreatment WBS. Five of 14 patients (36%) in the treatment group and eight of 25 (32%) in the control group had recurrence during the median 37 months of follow-up (P = 0.99). Changes in serum stimulated Tg concentrations did not differ between the two groups.nnnCONCLUSIONnEmpirical RAI therapy and posttreatment WBS were not useful diagnostically or therapeutically in patients with positive serum stimulated Tg if such patients had negative USG and negative FDG-PET findings after initial treatment of PTC.

Long-term clinical outcome of differentiated thyroid cancer patients with undetectable stimulated thyroglobulin level one year after initial treatment.

BACKGROUNDnMeasurement of the serum thyroglobulin (Tg) level with TSH stimulation (sTg) is the cornerstone of monitoring for the recurrence or persistence of differentiated thyroid cancer (DTC) in patients who have undergone surgery and remnant ablation. However, there have been several reports that an undetectable sTg could not predict the absence of future recurrence. The aim of this study was to evaluate the long-term outcome of DTC patients who achieved biochemical remission (BR, defined as sTg<1 ng/mL) after initial treatment, and to determine the role of repeated sTg measurement in detecting a clinical recurrence.nnnMETHODSnThis is a retrospective observational cohort study in a tertiary referral hospital. There were 1010 DTC patients who achieved BR at 12 months after the initial treatment (surgery and ablation), and they were eligible for analysis. Among them, 787 patients had values of repeated sTg.nnnRESULTSnThirteen out of 1010 (1.3%) patients had clinical recurrences during a median 84 months of follow-up. All of the clinical recurrences were limited to the cervical lymph nodes without clinical evidence of distant metastasis. Among 787 patients with available repeated sTg, 10 had clinical recurrences (5 out of 750 patients with repeated sTg<1 ng/mL and 5 out of 37 patients with repeated sTg ≥ 1 ng/mL). Patients with repeated sTg ≥ 1 ng/mL had a much greater chance of disease recurrence (log-rank statistics=43.7, df=1, p<0.001).nnnCONCLUSIONSnAbout 1% of DTC patients who had sTg<1 ng/mL 12 months after initial treatment had a clinical recurrence. All of clinical recurrences were loco-regional recurrences. Although repeated sTg measurement can be helpful to predict recurrence, we could not recommend it for surveillance in patients with BR due to its very low yield.

Technical and Oncologic Safety of Robotic Thyroid Surgery

BackgroundThe aim of this study was to evaluate the surgical outcomes of a double-incision robot-assisted gasless transaxillary thyroidectomy procedure compared with conventional open thyroid surgery.MethodsWe enrolled and analyzed 521 female patients with classic papillary thyroid carcinoma (PTC) who underwent a total thyroidectomy with central compartment node dissection (CCND) at the Asan Medical Center in Seoul, Korea from December 2008 to December 2010. These patients were classified into robotic (Nxa0=xa098) or open (Nxa0=xa0423) groups and were compared with respect to clinicopathologic characteristics, complications, and stimulated thyroglobulin (sTg) levels at the time of immediate postoperative radioactive iodine remnant ablation (ablation sTg) and at 6–12 months after the first ablation (control sTg).ResultsThe rate of perioperative complications was also similar, except for transient hypoparathyroidism in the robotic group. The median ablation sTg levels (0.39 vs 0.50xa0ng/mL, Pxa0=xa00.215) and the proportion of patients with ablation sTg levels <10xa0ng/mL (94.5 vs 98.0xa0%, Pxa0=xa00.103) were also comparable between the robotic and open groups. In addition, the proportion of patients with control sTg levels <1xa0ng/mL in both robotic and open groups (91.3 vs 95.6xa0%, Pxa0=xa00.079) did not show a significant difference.ConclusionsRobotic thyroid surgery using a double-incision gasless transaxillary approach is technically safe and may provide a feasible option for a complete thyroid resection and adequate lymph node dissection in patients with PTC.

Familial history of non‐medullary thyroid cancer is an independent prognostic factor for tumor recurrence in younger patients with conventional papillary thyroid carcinoma

It is not clear whether familial non‐medullary thyroid cancer (FNMTC) is more aggressive and has a poorer prognosis, than sporadic carcinoma. Therefore, the optimal clinical approach for FNMTC is yet to be established. In this study, we investigated the biological behavior and prognosis of FNMTC compared with its sporadic counterpart.

The Role of Core-Needle Biopsy as a First-Line Diagnostic Tool for Initially Detected Thyroid Nodules

BACKGROUNDnThe aim of this study was to evaluate the role of core-needle biopsy (CNB) as a first-line diagnostic tool for initially detected thyroid nodules.nnnMETHODSnThis observational study evaluated 632 initially detected thyroid nodules in 632 consecutive patients who underwent CNB between October 2008 and December 2011. CNB results were categorized into the six categories of the Bethesda System. A final diagnosis of malignancy was based on surgery or CNB, whereas a final diagnosis of benign nodules was based on surgery, two benign biopsy results, or benign cytology of stable size after one year. The rates of Bethesda category 1 and inconclusive results, diagnostic performance, unnecessary surgery, and complications were evaluated. Subgroup analysis based on nodule size was performed. Risk factors for inconclusive results were evaluated by multivariate logistic regression analysis.nnnRESULTSnThe rates of Bethesda category 1 and inconclusive results by CNB were 1.3% and 5.9%, respectively. The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for the diagnosis of malignancy were 97.6%, 90.0%, 100%, 100%, and 92.3%, respectively. The rate of unnecessary surgery was 0.5%, and the complications rate was 0.2%. Based on subgroup analysis, the diagnostic performance was not significantly associated with nodule size. There were no independent risk factors associated with inconclusive results.nnnCONCLUSIONnCNB showed low rates of Bethesda category 1 and inconclusive results and a high diagnostic accuracy. CNB also minimized unnecessary surgery. CNB seems to be a promising diagnostic tool for patients with initially detected thyroid nodules.

Recent Changes in the Clinical Outcome of Papillary Thyroid Carcinoma With Cervical Lymph Node Metastasis

CONTEXTnThe prognosis of papillary thyroid cancer (PTC) with cervical lymph node (LN) metastasis has changed with increased detection of subclinical metastatic LNs. The number and size of metastatic LNs were proposed as new prognostic factors in PTC with cervical LN metastasis (N1).nnnOBJECTIVEnThe objective of the study was to evaluate changes in N1 PTC characteristics and clinical outcome over time and to confirm the prognostic value of the number and size of metastatic LNs.nnnDESIGN AND PATIENTSnThis study included 1815 N1 PTC patients diagnosed between 1997 and 2011. Patients were classified into three risk groups according to the number and size of metastatic LNs: very low risk, five or fewer and 0.2 cm or less; low risk, five or fewer and 0.2 cm or greater; and high risk, more than five.nnnMAIN OUTCOME MEASURESnResponse to initial therapy and disease-free survival (DFS) was measured.nnnRESULTSnMetastatic LNs became smaller, and the ratio of metastatic LNs, which represents the extent of LN involvement and the completeness of surgery, decreased significantly over time. The proportion of patients with excellent response significantly increased from 33% to 67% over time (P < .001). These improvements were more evident in the low- and high-risk groups than in the very low-risk group. The DFS 5 years after initial surgery was also significantly increased from 73% to 91% over time (P < .001). The new LN classification was strongly associated with outcome. Patients in the very low-risk group had longer DFS than those in the low- and high-risk groups during the study period.nnnCONCLUSIONSnThe clinical outcome of N1 PTC has significantly changed over time with the earlier detection of thyroid cancers with less extensive LN involvement. More complete surgical neck dissection also might be responsible for these changes. The number and size of metastatic LNs are important prognostic factors of recurrence in N1 PTC.