Clinical Outcomes Following Letrozole Treatment according to Estrogen Receptor Expression in Postmenopausal Women: LETTER Study (KBCSG-006) / 한국유방암학회지

Purpose@#In this trial, we investigated the efficacy and safety of adjuvant letrozole for hormone receptor (HR)-positive breast cancer. Here, we report the clinical outcome in postmenopausal women with HR-positive breast cancer treated with adjuvant letrozole according to estrogen receptor (ER) expression levels. @*Methods@#In this multi-institutional, open-label, observational study, postmenopausal patients with HR-positive breast cancer received adjuvant letrozole (2.5 mg/daily) for 5 years unless they experienced disease progression or unacceptable toxicity or withdrew their consent. The patients were stratified into the following 3 groups according to ER expression levels using a modified Allred score (AS): low, intermediate, and high (AS 3–4, 5–6, and 7–8, respectively). ER expression was centrally reviewed. The primary objective was the 5-year disease-free survival (DFS) rate. @*Results@#Between April 25, 2010, and February 5, 2014, 440 patients were enrolled. With a median follow-up of 62.0 months, the 5-year DFS rate in all patients was 94.2% (95% confidence interval [CI], 91.8–96.6). The 5-year DFS and recurrence-free survival (RFS) rates did not differ according to ER expression; the 5-year DFS rates were 94.3% and 94.1%in the low-to-intermediate and high expression groups, respectively (p = 0.6), and the corresponding 5-year RFS rates were 95.7% and 95.4%, respectively (p = 0.7). Furthermore, 25 patients discontinued letrozole because of drug toxicity. @*Conclusion@#Treatment with adjuvant letrozole showed very favorable treatment outcomes and good tolerability among Korean postmenopausal women with ER-positive breast cancer, independent of ER expression.

Clinical Outcomes Following Letrozole Treatment according to Estrogen Receptor Expression in Postmenopausal Women: LETTER Study (KBCSG-006) / 한국유방암학회지

Purpose@#In this trial, we investigated the efficacy and safety of adjuvant letrozole for hormone receptor (HR)-positive breast cancer. Here, we report the clinical outcome in postmenopausal women with HR-positive breast cancer treated with adjuvant letrozole according to estrogen receptor (ER) expression levels. @*Methods@#In this multi-institutional, open-label, observational study, postmenopausal patients with HR-positive breast cancer received adjuvant letrozole (2.5 mg/daily) for 5 years unless they experienced disease progression or unacceptable toxicity or withdrew their consent. The patients were stratified into the following 3 groups according to ER expression levels using a modified Allred score (AS): low, intermediate, and high (AS 3–4, 5–6, and 7–8, respectively). ER expression was centrally reviewed. The primary objective was the 5-year disease-free survival (DFS) rate. @*Results@#Between April 25, 2010, and February 5, 2014, 440 patients were enrolled. With a median follow-up of 62.0 months, the 5-year DFS rate in all patients was 94.2% (95% confidence interval [CI], 91.8–96.6). The 5-year DFS and recurrence-free survival (RFS) rates did not differ according to ER expression; the 5-year DFS rates were 94.3% and 94.1%in the low-to-intermediate and high expression groups, respectively (p = 0.6), and the corresponding 5-year RFS rates were 95.7% and 95.4%, respectively (p = 0.7). Furthermore, 25 patients discontinued letrozole because of drug toxicity. @*Conclusion@#Treatment with adjuvant letrozole showed very favorable treatment outcomes and good tolerability among Korean postmenopausal women with ER-positive breast cancer, independent of ER expression.

Assessment of Quality of Life and Safety in Postmenopausal Breast Cancer Patients Receiving Letrozole as an Early Adjuvant Treatment / 한국유방암학회지

PURPOSE: There are few reports from Asian countries about the long-term results of aromatase inhibitor adjuvant treatment for breast cancer. This observational study aimed to evaluate the long-term effects of letrozole in postmenopausal Korean women with operable breast cancer. METHODS: Self-reported quality of life (QoL) scores were serially assessed for 3 years during adjuvant letrozole treatment using the Korean version of the Functional Assessment of Cancer Therapy-Breast questionnaires (version 3). Changes in bone mineral density (BMD) and serum cholesterol levels were also examined. RESULTS: All 897 patients received the documented informed consent form and completed a baseline questionnaire before treatment. Adjuvant chemotherapy was administered to 684 (76.3%) subjects, and 410 (45.7%) and 396 (44.1%) patients had stage I and II breast cancer, respectively. Each patient completed questionnaires at 3, 6, 12, 18, 24, 30, and 36 months after enrollment. Of 897 patients, 749 (83.5%) completed the study. The dropout rate was 16.5%. The serial trial outcome index, the sum of the physical and functional well-being subscales, increased gradually and significantly from baseline during letrozole treatment (p<0.001). The mean serum cholesterol level increased significantly from 199 to 205 after 36 months (p=0.042). The mean BMD significantly decreased from −0.39 at baseline to −0.87 after 36 months (p<0.001). CONCLUSION: QoL gradually improved during letrozole treatment. BMD and serum cholesterol level changes were similar to those in Western countries, indicating that adjuvant letrozole treatment is well tolerated in Korean women, with minimal ethnic variation.

Surgical Treatment Guidelines for Patients with Differentiated Thyroid Cancer: The Korean Association of Thyroid and Endocrine Surgeons (KATES) Guidelines Taskforce / 대한내분비외과학회지

No abstract available.

Expression of Histone Deacetylases HDAC1, HDAC2, HDAC3, and HDAC6 in Invasive Ductal Carcinomas of the Breast / 한국유방암학회지

PURPOSE: DNA deacetylation by histone deacetylase (HDAC) is an important mechanism involved in the oncogenic tumorigenesis of breast cancer. Previous studies have reported an association of the estrogen receptor (ER) with HDACs and demonstrated the efficacy of HDAC inhibitors for the treatment of breast cancers via in vitro experiments. In this study, we examined the association of HDAC expression with clinicopathological parameters and disease-specific survival. METHODS: Immunohistochemical (IHC) analysis of HDAC1, HDAC2, HDAC3, and HDAC6 was performed using tissue microarrays in 300 invasive ductal carcinomas. IHC scoring was determined by multiplication of the intensity (0 to 3) and the proportion (0 to 4) of staining, and we classified tumors into low- and high-HDAC expression groups. RESULTS: High expression of HDAC1 was correlated with the molecular subtype (p=0.001) and human epidermal growth factor 2 (HER2) amplification (p=0.012). High expression of HDAC6 was correlated with a younger age (p<0.001), ER expression (p=0.025), progesterone receptor expression (p=0.034), molecular subtype (p=0.023), and HER2 amplification (p=0.011). High HDAC1 expression was correlated with luminal A tumors (p=0.001), while high HDAC6 expression was more common in luminal B tumors (p=0.023). Although the expression of HDACs did not exhibit prognostic significance in the entire cohort, high expression of HDAC1 and HDAC6 was associated with improved overall survival (OS) in patients with ER-positive tumors (p=0.017 and p=0.029, respectively), and high expression of HDAC2 was correlated with improved OS in ER-negative tumors (p=0.048) on univariate analysis. Furthermore, high HDAC6 expression was associated with improved disease-free survival (p=0.048) on multivariate analysis. CONCLUSION: HDAC1 expression is significantly correlated with the molecular subtypes of tumors, with the highest expression being observed in luminal A tumors. HDAC6 is a significantly correlated with ER expression and the molecular subtype, thereby supporting the estrogen regulatory property of HDAC6. HDAC1 and HDAC6 expression are good prognostic factors for ER-positive tumors.

Comparison of the Effectiveness of Nonablative Fractional Laser versus Pulsed-Dye Laser in Thyroidectomy Scar Prevention

BACKGROUND: The anterior neck is the site of open thyroidectomy and where postoperative scarring can cause distress to patients. Both fractional and pulsed-dye lasers are effective and safe methods for preventing and improving surgical scars. OBJECTIVE: This study evaluated the improvement in scar appearance with laser intervention during the wound healing process. We evaluated the effect of nonablative fractional and pulsed-dye lasers on fresh thyroidectomy scars. METHODS: Patients were treated 3 times at 4-week interval with a follow-up visit at the 6th month. Scars were divided into 2 halves for each optional treatment. At every visit, a questionnaire evaluating the scar and patient satisfaction was completed. RESULTS: Thirty patients completed the 6-month process. The mean Vancouver Scar Scale scores improved significantly from 8.0 to 4.6 and 8.2 to 4.7 with nonablative fractional and pulsed-dye lasers, respectively (p<0.001). However, there was no significant difference between the 2 methods (p=0.840). CONCLUSION: There remains no consensus on the optimal treatment of scars. The present study indicates nonablative fractional and pulsed-dye lasers significantly improve scars. Nonablative fractional lasers are non-inferior to pulsed-dye lasers. Further studies are required to corroborate this finding.

Analysis of Predictive Factors for Lung Injury after Forward-Planned Intensity-Modulated Radiotherapy in Whole Breast Irradiation / 한국유방암학회지

PURPOSE: This study was performed to assess frequency, timings of occurrence, and predictors of radiologic lung damage (RLD) after forward-planned intensity-modulated radiotherapy (FIMRT) for whole breast irradiation. METHODS: We retrospectively reviewed medical records of 157 breast cancer patients and each of their serial chest computed tomography (CT) taken 4, 10, 16, and 22 months after completion of breast radiotherapy (RT). FIMRT was administered to whole breast only (n=152), or whole breast and supraclavicular regions (n=5). Dosimetric parameters, such as mean lung dose and lung volume receiving more than 10 to 50 Gy (V10-V50), and clinical parameters were analyzed in relation to radiologic lung damage. RESULTS: In total, 104 patients (66.2%) developed RLD after whole breast FIMRT. Among the cases of RLD, 84.7% were detected at 4 months, and 15.3% at 10 months after completion of RT. More patients of 47 or younger were found to have RLD at 10 months after RT than patients older than the age (11.7% vs. 2.9%, p=0.01). In univariate and multivariate analyses, age >47 and V40 >7.2% were significant predictors for higher risk of RLD. CONCLUSION: RLD were not infrequently detected in follow-up CT after whole breast FIMRT. More detected cases of RLD among younger patients are believed to have developed at later points after RT than those of older patients. Age and V40 were significant predictors for RLD after whole breast intensity-modulated radiotherapy.

Characteristics of BRCA1/2 Mutation-Positive Breast Cancers in Korea: A Comparison Study Based on Multicenter Data and the Korean Breast Cancer Registry / 한국유방암학회지

PURPOSE: Mutations in BRCA genes are the main cause of hereditary breast cancer in Korea. The aim of this study was to investigate the characteristics of breast cancers involving BRCA1 (BRCA1 group) and BRCA2 (BRCA2 group) mutations. METHODS: We retrospectively reviewed the medical records of patients with BRCA1 (BRCA1 group) or BRCA2 (BRCA2 group) mutation positive breast cancer from multiple centers and compared the data to that of the Korean Breast Cancer Society registry (registry group). RESULTS: The patients of the BRCA1 group were diagnosed at a younger age (median age, 37 years) and had tumors of higher histological (61.3% with histological grade 3) and nuclear (37.5% with nuclear grade 3) grade than those of the registry group. In addition, the frequency of ductal carcinoma in situ in the BRCA1 group was lower (3.7%) than in the registry group, and the BRCA1 group were more likely to be triple-negative breast cancer (61.3%). Patients in the BRCA2 group were also younger at diagnosis (mean age, 41 years) and were more likely to have involvement of the axillary node than the registry group (45.5% vs. 33.5%, p=0.002). The BRCA1 and BRCA2 groups did not show a correlation between tumor size and axillary node involvement. CONCLUSION: We report the characteristics of BRCA mutation positive breast cancer patients in the Korean population through multicenter data and nation-wide breast cancer registry study. However, BRCA-mutated breast cancers appear highly complex, and further research on their molecular basis is needed in Korea.

Simultaneous Occurrence of Ductal Carcinoma In Situ within Juvenile Fibroadenoma in Both Breasts: A Brief Case Report

No abstract available.

Evaluation of Short-Term Use of N-Acetylcysteine as a Strategy for Prevention of Anthracycline-Induced Cardiomyopathy: EPOCH Trial - A Prospective Randomized Study

BACKGROUND AND OBJECTIVES: We investigate to determine whether N-acetylcysteine (NAC) can prevent anthracycline-induced cardiotoxicity. SUBJECTS AND METHODS: A total of 103 patients were enrolled in this prospective randomized open label controlled trial. They are patients first diagnosed with breast cancer or lymphoma, who require chemotherapy, including anthracycline like adriamycine or epirubicine. Patients were randomized to the NAC group {n=50; 1200 mg orally every 8 hours starting before and ending after the intravenous infusion of anthracycline in all chemotherapy cycles (3-6)} or the control group (n=53). Primary outcome was the decrease in left ventricular ejection fraction (LVEF) absolutely > or =10% from the baseline and concomitantly <50% at 6-month. Composite of all-cause death, heart failure and readmission were compared. RESULTS: The primary outcome was not significantly different in the NAC and control groups {3/47 (6.4%) vs. 1/52 (1.9%), p=0.343}. The mean LVEF significantly decreased in both the NAC (from 64.5 to 60.8%, p=0.001) and control groups (from 64.1 to 61.3%, p<0.001) after the completion of whole chemotherapy. The mean LVEF change did not differ between the two groups (-3.64% in NAC vs. -2.78% in control group, p=0.502). Left ventricular (LV) end systolic dimension increased with higher trend in NAC by 3.08+/-4.56 mm as compared with 1.47+/-1.83 mm in the control group (p=0.064). LV end diastolic dimension did not change in each group and change does not differ in both. Peak E, A and E/A ratio change and cardiac enzymes were comparable in two groups. Cumulative 12-month event rate was 6% and 3.8% in the NAC group and the control group, respectively, with no difference (p=0.672). CONCLUSION: We cannot prove that NAC prevents anthracycline-induced cardiomyopathy.

Predictive Factors of Central Lymph Node Metastasis in Papillary Thyroid Microcarcinoma / 대한내분비외과학회지

PURPOSE: Despite the excellent overall prognosis for patients with papillary thyroid microcarcinoma (PTMC), the rate of central lymph node (CLN) metastasis has been reported to be as great as 60% and the optimal surgical extent of PTMC has been controversial. The aim of this study is to identify factors for predict CLN metastasis in patients with PTMC. METHODS: We conducted a retrospective study of 535 patients with PTMC who underwent total thyroidectomy with prophylactic CLN dissection between Jan. 2008 and Aug. 2011. We analyzed the association of CLN metastasis and clinicopathologic characteristics. RESULTS: CLN metastasis was found in 181 patients (33.8%). Results of univariate analysis showed an association of younger than 45 years of age, male gender, a tumor size greater than 5 mm, bilaterality, multiplicity, extrathyroidal extension, and positivity of resection margin with CLN metastasis. Of these, results of multivariate analysis showed that age (P=0.003), gender (P=0.004), tumor size (P5 mm), male gender, young age (<45 yr), extrathyroidal extension, and positive resection margin were determined as the predictive factors for CLN metastasis, which occurred in approximately one third of patients with PTMC. Therefore, prophylactic CLN dissectionshould be considered in patients with PTMC who have these factors through investigation before surgery.

The Current Role of Vacuum Assisted Breast Biopsy System in Breast Disease / 한국유방암학회지

The gold standard for breast biopsy procedures is currently an open excision of the suspected lesion. However, an excisional biopsy inevitably makes a scar. The cost and morbidity associated with this procedure has prompted many physicians to evaluate less invasive, alternative procedures. More recently, image-guided percutaneous core-needle biopsy has become a frequently used method for diagnosing palpable and non-palpable breast lesions. Although sensitivity rates for core-needle biopsy are high, it has the disadvantage of histological underestimation, which renders the management of atypical ductal hyperplasia, papillary lesions, and fibroepithelial lesions somewhat difficult. Vacuum assisted breast biopsy (VABB) was developed to overcome some of these negative aspects of core-needle biopsy. VABB allows for a sufficient specimen to be obtained with a single insertion and can provide a more accurate diagnosis and completely remove the lesion under real-time ultrasonic guidance. The advantage of complete lesion removal with VABB is to reduce or eliminate sampling error, to decrease the likelihood of a histological underestimation, to decrease imaging-histological discordance, to decrease the re-biopsy rate, and to diminish the likelihood of subsequent growth on follow-up. In recent years, with the advancement of VABB instruments and techniques, many outcome studies have reported on the use of VABB for resecting benign breast lesions with a curative intent. VABB is highly accurate for diagnosing suspicious breast lesions and is highly successful at treating presumed benign breast lesions. Thus, in the near future, VABB will be routinely offered to all appropriately selected patients.

alphaB-Crystallin is a Novel Oncoprotein Associated with Poor Prognosis in Breast Cancer / 한국유방암학회지

PURPOSE: alphaB-crystallin, a small heat shock protein, is an anti-apoptotic protein associated with aggressive tumor behavior. A recent study revealed that alphaB-crystallin is overexpressed in a metastatic variant of the GI101A human breast carcinoma cell line. The purpose of this study was to investigate whether alphaB-crystallin is related to other breast tumor markers and can predict a breast cancer prognosis. METHODS: Eighty-two patients who underwent breast cancer surgery at Hallym Sacred Heart Hospital were enrolled. alphaB-crystallin expression was determined by immunohistochemical staining. Estrogen receptor, progesterone receptor (PR), human epidermal growth factor receptor, lymphovascular invasion, histological grade, other tumor markers and time to recurrence were compared with alphaB-crystallin expression. RESULTS: alphaB-crystallin expression in breast cancer tissues was associated with PR (p=0.030), the number of metastatic lymph nodes (pN) (p=0.020), lymphovascular invasion (p=0.022), histological grade (p=0.004) and triple negative breast cancer (TNBC) (p=0.004). alphaB-crystallin expression significantly decreased time to recurrence (p=0.039). CONCLUSION: The results revealed a strong relationship between alphaB-crystallin and poor prognostic factors such as the number of metastatic lymph nodes (especially pN2), TNBC, and rapid time to recurrence. We believe that alphaB-crystallin could be a novel oncoprotein biomarker of a poor prognosis in breast cancer.

Antiproliferation and Redifferentiation in Thyroid Cancer Cell Lines by Polyphenol Phytochemicals

Thyroid carcinogenesis is accompanied by loss of thyroid-specific functions and refractory to radioiodine and thyroid stimulating hormone (TSH) suppression therapy. Redifferentiating agents have been shown to inhibit tumor growth and improve the response to conventional therapy. Polyphenol phytochemicals (PPs) in fruits and vegetables have been reported to inhibit cancer initiation, promotion, progression and induce redifferentiation in selected types. In this study we examined PPs induce redifferentiation in thyroid cancer cell lines. We investigated the effects of genistein, resveratrol, quercetin, kaempferol, and resorcinol on the F9 embryonal carcinoma cell differentiation model. The thyroid cancer cell lines, TPC-1, FTC-133, NPA, FRO, and ARO, displayed growth inhibition in response to genistein, resveratrol, quercetin. We further demonstrated that genistein decreased the dedifferention marker CD97 in NPA cells and resveratrol decreased CD97 in FTC-133, NPA, FRO cells and quercetin decreased CD97 in all cell lines. We observed increased expression of differentiation marker NIS in FTC-133 cells in response to genistein, and resveratrol but no change in NPA, FRO, ARO cells. Quercetin increased or induced NIS in FTC-133, NPA, FRO cells. These findings suggest that PPs may provide a useful therapeutic intervention in thyroid cancer redifferentiation therapy.

Heat Shock Protein as Molecular Targets for Breast Cancer Therapeutics / 한국유방암학회지

Recent advances in the understanding of the molecular mechanisms involved in the breast cancer development and progression have led to the identification of numerous novel molecular targets. Among these, heat shock proteins (HSPs) are being emerging molecular target due to its diverse function in cancer cells. HSPs are highly conserved molecular chaperone that are synthesized by cell in response to various stress conditions. Mammalian HSPs have been classified into several families according to their molecular weight: HSP100, HSP90, HSP72, and small molecular HSPs (including HSP27). They are essential proteins that play a key role in cell survival through the cytoprotective mechanisms. In addition, HSPs are often overexpressed in a rage of cancers including breast cancer, and its overexpression seems to be associated with poor clinical outcomes. Also, HSP90 play a role in facilitating transformation by stabilizing the mutated and overexpressed oncoproteins found in breast cancer cell. Pharmacological targeting of HSP is therefore indicated and in the case of HSP90, numerous inhibitory drugs are undergoing clinical trial for treatment of breast cancer and other cancers. In this review, we describe the roles of HSPs in cancer cell and introduce the HSPs inhibitor as molecular target in cancer therapy and its recent clinical trials in breast cancer.

The Author Response: Antiproliferation and Redifferentiation in Thyroid Cancer Cell Line by Polyphenol Phytochemicals

No abstract available.

The Change of Practice Patterns of the Hereditary Breast Cancer Management in Korea after the Korean Hereditary Breast Cancer Study / 한국유방암학회지

PURPOSE: The objective of this study was to evaluate the change in the practice patterns for managing hereditary breast and ovarian cancer (HBOC) among Korean physicians after the Korean Hereditary Breast Cancer (KOHBRA) study. METHODS: The first survey was performed from July to August 2007, at the initiation of the KOHBRA study, and the follow-up survey was conducted from July to December 2009. Members of the Korean Breast Cancer Society were invited to participate in the study by e-mail. The 2009 survey was conducted with a self-administered questionnaire concerning HBOC management and was identical to the previous questionnaire. RESULTS: According to the 2009 survey, most physicians (60.0%) tended to draw a pedigree (48.0% in 2007 survey). The rate of genetic test recommendations for patients at risk for HBOC was higher in the 2009 survey (84.0%) than that in the 2007 survey (64.0%). Physicians tended to select a BRCA genetic testing candidate more appropriately than in the previous survey (42.4% answered right in 2007 survey; 74.4% in 2009 survey). Fifteen of 25 participants (60.0%) provided genetic counseling before their patients underwent a genetic test, which was higher than that (40.0%) in the 2007 survey. According to the 2009 survey, half of the genetic counseling was being conducted by KOHBRA study research nurses; whereas most of the genetic counseling was conducted by physicians in 2007. CONCLUSION: The KOHBRA study has played an important role in the appropriate selection of candidates for genetic testing. However, more effort should be placed on improving the pre-test genetic counseling rate.

Hormone Replacement Therapy and Breast Cancer: The Situation in Korea / 한국유방암학회지

No abstract available.

Clinical Significance of p53, Ki-67 and Galectin-3 Expressions in Papillary Thyroid Carcinoma

PURPOSE: There are few molecular markers useful in practice for predicting prognosis of papillary thyroid carcinoma (PTC) despite numerous basic researches. The objective of this study was to evaluate the prognostic values of several candidate markers of PTC (p53, Ki-67 and galectin-3) using immunohistochemistry (IHC), one of the most practical methods. METHODS: IHC for p53, Ki-67 and galectin-3 were performed on formalin-fixed paraffin-embedded tissues of 160 PTC specimens using monoclonal antibodies. The associations of the expressions of these markers with multiple clinicopathologic prognostic factors were assessed. RESULTS: The overexpresion rates of p53, Ki-67 and galectin-3 were 48.8%, 64.3% and 97.8%, respectively. Overexpression of p53 protein was positively associated with extrathyroidal extension (P<0.001). In addition, p53 immunoreactivity was more prevalent among Ki-67 overexpressed specimens (P<0.001). Ki-67 immunoreactivity was positively correlated with tumor size (P<0.05), which became more distinct when accompanied with p53 overexpression (P<0.01). In contrast, no relationship between galectin-3 immunoreactivity and clinical prognostic factors was found. CONCLUSION: Our results suggest that overexpression of p53 protein and Ki-67 in papillary thyroid carcinoma is associated with tumor progression and that IHC for these proteins could be useful for predicting prognosis of patients with PTC.

Preoperative USG and CT Scanning for Predicting Regional LN Metastasis of Papillary Thyroid Carcinoma / 대한내분비외과학회지

PURPOSE: Lymph node (LN) metastasis of papillary thyroid carcinoma (PTC) is related to a high local recurrence rate and a low disease-specific survival rate. So, the diagnosis of LN metastasis according to the compartment is important for surgical planning. We evaluated the value of preoperative USG and CT for predicting LN metastasis METHODS: USG, CT or both were performed preoperatively for 325 consecutive patients who were newly diagnosed with PTC and who were operated on between Dec 1, 2004 and Dec 31, 2008. The reports of the preoperative USG and CT were compared with the histopathologic results. The accuracy of these studies for assessing LN metastasis were calculated, and we investigated whether combined USG and CT (US/CT) showed any additional benefit over USG or CT only. RESULTS: For the central compartment, USG, CT and US/CT showed high specificities (98.2%, 98.6%, 98.2%, respectively) and low sensitivities (7.1%, 4.6%, 12.0%, respectively), and US/CT showed higher sensitivity than CT only. For the lateral compartment, USG demonstrated higher sensitivity and lower specificity compared with CT (76.2% vs 43.5%, 50.0% vs 70.0%, respectively), and US/CT had a higher sensitivity than CT only (81.0% vs 43.5%, respectively). By the per patient analysis, the sensitivity of US/CT (38.6%) was higher than those of USG (30.6%) or CT (19.3%),and the specificity was highest for CT (96.4%). CONCLUSION: Prophylactic central LN dissection for PTC can be justifiedby the low sensitivity and high specificity of USG and CT for predicting central LN metastasis. For the lateral LN compartment, a combination of USG and CT can increase the sensitivity for predicting LN metastasis.