Functional viromic screens uncover regulatory RNA elements.

The number of sequenced viral genomes has surged recently, presenting an opportunity to understand viral diversity and uncover unknown regulatory mechanisms. Here, we conducted a screening of 30,367 viral segments from 143 species representing 96 genera and 37 families. Using a library of viral segments in 3' UTR, we identified hundreds of elements impacting RNA abundance, translation, and nucleocytoplasmic distribution. To illustrate the power of this approach, we investigated K5, an element conserved in kobuviruses, and found its potent ability to enhance mRNA stability and translation in various contexts, including adeno-associated viral vectors and synthetic mRNAs. Moreover, we identified a previously uncharacterized protein, ZCCHC2, as a critical host factor for K5. ZCCHC2 recruits the terminal nucleotidyl transferase TENT4 to elongate poly(A) tails with mixed sequences, delaying deadenylation. This study provides a unique resource for virus and RNA research and highlights the potential of the virosphere for biological discoveries.

A Patient of Venous Hemangioma of the Inferior Turbinate.

Sinonasal hemangiomas are relatively rare among the hemangiomas that occur from the head and neck parts. According to their histopathologic findings, they are classified as capillary, cavernous, or venous type. Some cases of capillary or cavernous hemangioma that occur from the inferior turbinate have been reported. However, there was no reported case of venous hemangioma arising from the inferior turbinate. We present a case of 67-year-old male who has venous hemangioma of the left inferior turbinate whose initial symptoms were watery rhinorrhea and postnasal drip. With this study, although uncommon, venous hemangioma should be considered as a differential diagnosis in patient with mass lesion of the inferior turbinate.

Expression of VISTA on tumor-infiltrating immune cells correlated with short intravesical recurrence in non-muscle-invasive bladder cancer.

V-domain immunoglobulin suppressor of T cell activation (VISTA) is an immune checkpoint molecule expressed in hematopoietic cells, granulocytes, macrophages, and monocytes. However, few studies to date have investigated VISTA expression, especially its clinical utility, in bladder cancer. The present retrospective study aimed to examine VISTA, programmed death ligand-1 (PD-L1), and CD45 expression by immunohistochemical and immunofluorescence staining of archived pathological tissue samples from 159 patients with primary bladder cancer. The correlation between VISTA expression in immune cells (ICs) and clinicopathologic variables including PD-L1 expression in ICs was examined. Briefly, the rates of VISTA-positive ICs and VISTA-positive tumor cells were 67.9% (108/159) and 30.8% (49/159), respectively. The VISTA expression in ICs of patients with bladder cancer, including those with non-muscle-invasive bladder cancer (NMIBC), was positively correlated with tumor stage, grade, size, and multiplicity. The VISTA expression in ICs was stronger in bladder cancer cases with PD-L1-positive ICs than in those with PD-L1-negative ICs (p < 0.001). The mean intravesical recurrence-free survival was shorter in NMIBC cases with VISTA-positive ICs than in those with VISTA-negative ICs (34.0 vs 39.9 months, p = 0.03, log-rank test). In this first study to investigate VISTA expression in bladder cancer, these results implicate VISTA as a potential immunotherapeutic target and immunologic biomarker in bladder cancer.

The application of bacteriophage to control Cronobacter sakazakii planktonic and biofilm growth in infant formula milk.

The goal was to identify the biofilm-forming ability of Cronobacter sakazakii on surfaces of stainless steel (SS) and silicone rubber (SR) in contact with infant formula milk. Two representative bacteriophages (PBES04 and PBES19) were used to control the growth of C. sakazakii as well as its biofilm forming ability on either SS or SR surfaces. Bacterial growth was confirmed at 20 °C when PBES04 and PBES19 were used, whereas C. sakazakii was not normally detected in infant formula milk treated with both bacteriophages for 6 h. In an additional biofilm reduction experiment, the biofilm on SS or SR surfaces were reduced by 3.07 and 1.92 log CFU cm-2, respectively after PBES04 treatment, and 3.06 and 2.14 log CFU cm-2, respectively, after PBES19 treatment. These results demonstrate that bacteriophages can be effective in inactivating C. sakazakii in biofilms which could potentially increase food safety in commercial facilities.

Nuclear aconitase antagonizes heterochromatic silencing by interfering with Chp1 binding to DNA.

In Schizosaccharomyces pombe, there are two aconitases, Aco1 and Aco2, involved in the Krebs cycle in mitochondria. Interestingly, Aco2 is localized to nucleus as well. Here, we investigated the nuclear role of Aco2 by deleting its nuclear localization signal. The aco2ΔNLS mutation suppressed the gene-silencing defects of RNAi mutants at the centromere, where heterochromatin formation depends on RNAi pathway. In Δago1, the aco2ΔNLS mutation restored heterochromatin through elevating Chp1 binding. Aco2 physically interacted with Chp1 via the N-terminal chromodomain that binds to methylated histone H3K9. In the sub-telomeric region, where heterochromatin forms independent of RNAi pathway, the single aco2ΔNLS mutation caused extra gene silencing via elevating Chp1 binding, without increasing histone methylation. The anti-silencing effect did not require the catalytic function of aconitase. Taken together, Aco2 functions as an epigenetic regulator of gene expression, through associating with chromodomain of Chp1 to maintain heterochromatin.

FACTORS INFLUENCING THE SUCCESSFUL MAINTENANCE OF EUTHYROIDISM AFTER LOBECTOMY IN PATIENTS WITH PAPILLARY THYROID MICROCARCINOMA: A SINGLE-CENTER STUDY.

Objective: This study aimed to evaluate factors influencing the successful maintenance of postoperative euthyroidism in patients who did not undergo immediate thyroid hormone replacement after lobectomy for papillary thyroid microcarcinoma (PTMC). Methods: From September 2015 to June 2017, 186 patients underwent lobectomy for PTMC in our hospital. Patients taking medications for hypothyroidism and hyperthyroidism before and after lobectomy were excluded. Multiple parameters, including sex, age, pre-operative free thyroxine (T4), thyroid-stimulating hormone (TSH), thyroglobulin (TG), and thyroid autoantibody levels, body mass index (BMI), postoperative histopathology of the thyroid gland, remnant thyroid gland volume, and session number of levothyroxine discontinuation were retrospectively evaluated. These factors were compared between groups based on the maintenance of postoperative euthyroidism. Results: In 88 of the 175 patients (50.3%), postoperative euthyroidism was successfully maintained without thyroid hormone replacement during the first year after lobectomy. There were significant differences in sex (P = .003), pre-operative TSH levels (P = .002), and histopathology of the thyroid gland (P = .035) between the groups showing maintenance success and failure. The group showing successful maintenance had a higher percentage of male patients, lower levels of pre-operative TSH, and normal parenchymal histology of the thyroid gland. However, there were no significant between-group differences in age, pre-operative free T4, TG, and thyroid autoantibody levels, BMI, remnant thyroid gland volume, and session number of levothyroxine discontinuation. Conclusion: Patient sex, pre-operative TSH levels, and histopathology of the thyroid gland may influence the maintenance of postoperative euthyroidism after lobectomy. Abbreviations: BMI = body mass index; PTMC = papillary thyroid microcarcinoma; RR = reference range; T4 = thyroxine; TFT = thyroid function test; TG = thyroglobulin; TSH = thyroid-stimulating hormone.

Utility of Preoperative Ultrasonography in Transferred Patients with Suspicious Malignancy on Ultrasonography-Guided Fine-Needle Aspiration Cytology of Thyroid Nodules: A Single-Center Retrospective Study.

BACKGROUND This study aimed to assess the utility and characteristics of preoperative ultrasonography (US) in patients transferred to referral hospitals from local clinics with a diagnosis of malignancy on US-guided fine-needle aspiration cytology of thyroid nodules. MATERIAL AND METHODS From January 2018 to June 2018, 109 transferred patients underwent preoperative US in our hospital for suspected thyroid malignancy on cytological analysis after US-guided fine-needle aspiration of thyroid nodules in local clinics. Preoperative US was performed by a single radiologist in all patients. Among them, 6 were excluded from the study because of refusal of thyroid surgery. Preoperative US and histopathological results were compared in all patients. RESULTS After thyroid surgery, pathological examination revealed papillary thyroid carcinoma (PTC) (n=98), follicular adenoma (n=1), and nodular hyperplasia (n=4). Of the 103 patients, 91 exhibited suspicious US findings on the preoperative US, whereas 12 did not. In the 91 patients with suspicious US findings, PTC (n=90) and follicular adenoma (n=1) were confirmed after thyroid surgery. In the 12 patients with no suspicious US findings, PTC (n=8) and nodular hyperplasia (n=4) were confirmed after thyroid surgery. On repeat analysis of the cytological slides of the 4 nodular hyperplasia cases from the local clinics, Bethesda category II (n=1) and III (n=3) were determined. CONCLUSIONS In the transferred patients with a malignant cytology, preoperative US might be helpful to detect false-positive cytology cases.

Comparison of Prevalence and Ultrasonography Features of Thyroglossal Duct Cyst in Adults According to Radioactive Iodine Ablation.

BACKGROUND This study aimed to evaluate the prevalence of thyroglossal duct cysts (TGDCs) on ultrasonography (US) and US features of TGDCs in adults, and to assess whether the prevalence or size of TGDCs increases after radioactive iodine ablation (RIA). MATERIAL AND METHODS Between July and December 2018, 2820 patients underwent thyroid or neck US examination, performed by 2 radiologists, at our center. On the basis of real-time US, the presence or absence of TGDCs was prospectively investigated by 2 radiologists. Among the 2820 patients, 54 patients who were <19 years of age or had a radiation therapy history to the neck were excluded. Eventually, 2766 patients were included. RESULTS Of the 2766 patients, 160 (5.8%) showed a TGDC on US. The mean size of TGDCs in RIA history (+) (n=36) and RIA history (-) (n=124) groups was 0.92±0.41 cm and 0.86±0.45 cm, respectively. There was no significant difference in size of TGDCs between RIA history (+) and RIA history (-) groups (p=0.684). Between the TGDC (+) and TGDC (-) groups, there was no significant difference in patient age, gender, reason for thyroid/neck US, type of thyroid surgery, and session number and application/no application of RIA (p>0.05). The prevalence rate of TGDCs in radiologist A and B was 4.9% (70/1427) and 6.7% (90/1339), respectively. TGDCs were more common in the suprahyoid neck, and the common shapes of TGDCs were flat-to-ovoid and round. CONCLUSIONS RIA may not be associated with the prevalence or enlargement of TGDCs.

SONOGRAPHIC FEATURES OF MULTIFOCAL PAPILLARY THYROID CARCINOMAS.

OBJECTIVE: It is uncertain whether papillary thyroid carcinomas (PTCs) of the same subtype display similar sonographic features. This retrospective analysis of pre-operative sonographic and pathologic findings aimed to assess whether PTCs of the same subtype share sonographic features. METHODS: Before undergoing thyroid surgery, 137 patients underwent ultrasound (US) examination. A single radiologist used a picture archiving and communication system and pathologic reports to investigate all sonographic features of the largest and second largest PTCs. Additionally, the radiologist evaluated the similarity of sonographic features between primary (largest), secondary (second largest), and daughter (secondary with same subtype as the primary) PTCs. RESULTS: Of the 137 PTC patients, 48 (35.0%) had multiple PTCs; however, 5 had no US images of the secondary PTC. Of the 43 secondary PTCs with US images, 9 (20.9%) secondary PTCs were of a different subtype than the primary PTC and revealed sonographic features that differed from those of the primary PTC. Of the 48 patients with multiple PTCs, the subtype was the same in the primary and secondary PTCs in 34 (70.8%) patients. Of the 34 daughter PTCs, 32 (94.1%) had sonographic features similar to those of the primary PTC, whereas 2 (5.9%) showed different sonographic features than the primary PTC. There was no significant difference between primary and daughter PTCs in the size, location, sonographic features, or Korean Thyroid Imaging Reporting and Data System category ( P>.05). CONCLUSION: Daughter PTCs show similar sonographic features as the primary PTC. ABBREVIATIONS: K-TIRADS = Korean Thyroid Imaging Reporting and Data System; PTC = papillary thyroid carcinoma; US = ultrasound.

Utility of routine ultrasonography follow-up after total thyroidectomy in patients with papillary thyroid carcinoma: a single-center study.

BACKGROUND: This study aimed to assess the appropriate number of sessions and interval of routine follow-up ultrasonography (US) in patients who underwent total thyroidectomy for papillary thyroid carcinoma (PTC). METHODS: Between January 2008 and December 2009, 569 patients underwent total thyroidectomy for PTC. Of the 569 patients, 44 were excluded from the study because of no US follow-up data for the neck (n = 43) or owing to indeterminate tumor recurrence/persistence (n = 1). The follow-up US for all the patients was performed by a single radiologist. Based on the cytohistopathological results, tumor recurrence/persistence was determined. RESULTS: In the 525 patients, the mean interval to the last follow-up US was 54.7 months, and the mean number of follow-up US sessions was 4.4. Of the 525 patients, 31 (5.9%) showed nodal (n = 30) and non-nodal (n = 1) tumor recurrence/persistence. Patient age and N stage were independently associated with tumor recurrence/persistence. Among patients showing tumor recurrence/persistence after total thyroidectomy, the time at first detection of suspicious US findings on follow-up US was ≤8 months in 2 patients, between 10 and 23 months in 21, and ≥ 25 months in 8. In a receiver operating characteristic curve analysis, the number of sessions and interval of the provided follow-up US were inappropriate for the detection of tumor recurrence/persistence. CONCLUSIONS: For the detection of tumor recurrence/persistence after total thyroidectomy in PTC patients, routine US follow-up with a 1- or 2-year interval may be excessive.

Amyloid goiter mimicking subacute thyroiditis on clinical and imaging findings: A case report.

Amyloid goiter (AG) is defined as the diffuse enlargement of the thyroid gland resulting from extensive amyloid deposition. Imaging findings in AG may vary depending on the amount of amyloid and fat deposition. A few case reports of AG with clinically subacute thyroiditis (SAT)-like syndrome have been published. However, there have been no reports on AG mimicking SAT with clinical and imaging findings. Herein, we present a case of AG mimicking SAT with a detailed report of the clinical and imaging findings.

Computed Tomography Features of Benign and Malignant Calcified Thyroid Nodules: A Single-Center Study.

OBJECTIVE: No previous studies have investigated thyroid calcification on computed tomography (CT) quantitatively by using Hounsfield unit (HU) values. This study aimed to analyze quantitative HU values of thyroid calcification on preoperative neck CT and to assess the characteristics of benign and malignant calcified thyroid nodules (CTNs). MATERIALS AND METHODS: Two hundred twenty patients who underwent neck CT before thyroid surgery from January 2015 to June 2016 were included. On soft-tissue window CT images, CTNs with calcified components of 3 mm or larger in minimum diameter were included in this study. The HU values and types of CTNs were determined and analyzed. RESULTS: Of 61 CTNs in 49 patients, there were 42 malignant nodules and 19 benign nodules. The mean largest diameter of the calcified component was 5.3 (2.5) mm (range, 3.1-17.1 mm). A statistically significant difference was observed in the HU values of calcified portions between benign and malignant CTNs, whereas there was no significant difference in patient age or sex or in the size, location, or type of each CTN. Of the 8 CTNs with pure calcification, 3 exhibited a honeycomb pattern on bone window CT images, and these 3 CTNs were all diagnosed as papillary thyroid carcinoma on histopathological examination. CONCLUSIONS: Hounsfield unit values of CTNs may be helpful for differentiating malignancy from benignity.

Ultrasound detection of normal parathyroid glands: a preliminary study.

OBJECTIVE: No previous prospective study has investigated the detection of normal parathyroid glands (PTGs) and their features using real-time ultrasound (US). This study aimed to assess the preoperative US detection of normal PTGs in patients who underwent hemithyroidectomy. METHODS: Between August and October 2016, 44 patients underwent hemithyroidectomy using a low-collar incision, and 5 were excluded from the study. A single radiologist performed the preoperative US examination in all patients, and the surgical data for the PTGs were obtained by a single surgeon. Based on the surgical findings of PTGs, the preoperative US detection of PTGs was determined. RESULTS: Of the 39 patients, 3 had no surgical data for PTG (n = 2) and the presence of parathyroid hyperplasia (n = 1). In the 36 remaining patients, in 3 patients, US identification of a normal PTG was corroborated by surgical findings, whereas in 2 patients, US findings differed from surgical findings, and in 31 patients, US did not detect a normal PTG. The successful US detection rate of normal PTG was only 8.3% (3/36). CONCLUSIONS: US cannot be used for identification of normal PTGs.

Factors Influencing the Outcome of Ultrasound-Guided Fine-Needle Aspiration for Salivary Gland Lesion Diagnosis.

OBJECTIVES: This study aimed to assess multiple factors influencing the outcomes of ultrasound (US)-guided fine-needle aspiration (FNA) of salivary gland lesions. METHODS: From 2008 to 2013, a single radiologist performed US-guided FNA of salivary gland lesions in 243 patients. With the exclusion of pure cysts, poor image quality, and insufficient static image cases, 218 salivary gland lesions in 218 patients were included. The composition, size, location, and vascularity of the lesions were retrospectively investigated on the basis of sonographic findings by the same radiologist. The relationship between sampling adequacy and multiple factors was compared, and the diagnostic accuracy of US-guided FNA of salivary gland lesions was calculated by using the final diagnosis as a reference standard. RESULTS: The sampling adequacy rate for US-guided FNA of the 218 salivary gland lesions was 96.8% (211 of 218). A significant difference was observed in the composition and vascularity of the lesions (P < .0001), whereas there was no significant difference in the patient age and sex, lesion size, lesion location, and needle size. The rate of inadequate sampling increased in predominantly cystic lesions compared with solid lesions as well as in low-vascularity lesions compared with high-vascularity lesions. Of the 218 lesions, 178 (81.7%) were ultimately diagnosed, and most were benign (162 of 178 [91.0%]). When 3 cases with indeterminate cytologic results were excluded, the sensitivity, specificity, positive and negative predictive values, and accuracy of US-guided FNA of salivary gland lesions were 64.3%, 98.8%, 81.8%, 97.0%, and 96.0%, respectively. CONCLUSIONS: When using US-guided FNA to diagnose salivary gland lesions, sampling adequacy depends on the composition or vascularity of the lesions.

Relationships between transporter expression and the status of BRAF V600E mutation and F-18 FDG uptake in papillary thyroid carcinomas.

PURPOSE: The purpose of this study was to evaluate the expression of the glucose transporters GLUT1 and GLUT3 in papillary thyroid carcinomas (PTCs) and to elucidate their relationship with the BRAF V600E mutation and F-18 FDG uptake. MATERIALS AND METHODS: We retrospectively analyzed data of 52 PTC patients (41 women and 11 men; mean age, 52.4 ± 14.5 years). F-18 FDG PET/CT was performed preoperatively, and the maximum standardized uptake value (SUVmax) was calculated. GLUT1/GLUT3 expression was determined immunohistochemically, and the BRAF V600E mutation was detected using DNA sequencing. RESULTS: GLUT1 and GLUT3 were expressed in 82.7% (43/52) and 59.6% (31/52) PTCs, respectively. The BRAF V600E mutation was detected in 65.4% (34/52) PTCs. The odds ratio between GLUT1 expression and the BRAF V600E mutation was 5.2 (95% CI, 1.11-24.05; p < 0.05), and that between GLUT3 expression and the BRAF V600E mutation was 3.8 (95% CI, 1.14-12.53; p < 0.05). The SUVmax of PTCs was significantly higher if they carried the BRAF V600E mutation (11.3 ± 2.0, compared with 5.7 ± 1.4 for wild type BRAF tumors, Mann-Whitney test, p = 0.016). Neither GLUT1 nor GLUT3 expression was significantly associated with the SUVmax of F-18 FDG PET/CT in PTCs. CONCLUSIONS: Our findings confirmed that both GLUT1 and GLUT3 are strongly expressed by PTCs, although their expression was not significantly associated with the SUVmax of F-18 FDG PET/CT. However, GLUT1 and GLUT3 expressions were significantly associated with the presence of the BRAF V600E mutation, and the SUVmax of tumors was significantly higher in the presence of the mutated BRAF gene.

Computed tomography features of benign and malignant solid thyroid nodules.

BACKGROUND: No previous study has investigated computed tomography (CT) features of benign and malignant solid thyroid nodules using detailed CT features and histopathological results. PURPOSE: To assess CT features of benign and malignant solid thyroid nodules in patients who underwent thyroid surgery. MATERIAL AND METHODS: From January to April 2014, 151 consecutive patients underwent neck CT before thyroid surgery. In each case, neck CT was retrospectively examined by a single radiologist. We evaluated the diagnostic accuracy of specific CT features for differentiating malignant from benign thyroid nodules using histopathological results as a reference standard. RESULTS: Of 173 thyroid nodules in 142 patients, 162 (mean diameter, 12.8 ± 10.3 mm; range, 5.0-93.7 mm) were visualized on neck CT. Of 162 nodules in 133 patients, 116 were malignant and 46 were benign as confirmed by histopathology. A multivariate logistic regression analysis showed a significant difference between malignant and benign thyroid nodules in the degree and pattern of nodular enhancement, but there were no significant differences in other CT features. In particular, thyroid nodules with exophytic configuration, irregular margin, taller-than-wide shape, punctate calcifications, or homogeneously decreased enhancement showed a high malignancy rate. CONCLUSION: The study demonstrated that the degree and pattern of nodular enhancement are helpful CT features for differentiating malignant from benign solid thyroid nodules.

Sonographically based diagnosis of contralateral malignancy in preoperative patients with papillary thyroid microcarcinoma.

OBJECTIVES: We aimed to assess the usefulness of sonographically based diagnosis to predict whether contralaterally located dominant thyroid nodules are malignant or benign in patients with known papillary thyroid microcarcinoma. METHODS: We studied 143 patients with primary papillary thyroid microcarcinoma who underwent preoperative thyroid sonography. Each dominant thyroid nodule was prospectively classified into 1 of 5 diagnostic categories by a single radiologist: benign, probably benign, borderline, possibly malignant, and malignant. We calculated the efficacy of sonographic diagnosis for contralateral malignancy by using histopathologic or long-term sonographic follow-up results as reference standards. RESULTS: Of the 143 primary papillary thyroid microcarcinomas, 17 showed satellite carcinomas; hence, the bilaterality rate in all patients was 11.9% (17 of 143). Real-time sonography of the contralateral thyroid yielded no thyroid nodules (n = 55) and benign (n = 52), probably benign (n = 10), borderline (n = 13), possibly malignant (n = 4), and malignant (n = 9) nodules. When the borderline sonographic class was excluded, the sensitivity, specificity, positive and negative predictive values, and accuracy of sonographic diagnosis for detecting contralateral malignancy were 86.7%, 100%, 100%, 98.3%, and 98.5%, respectively. Within individual sonographic classes for the dominant thyroid nodules, the diagnostic accuracy rates for classes IV and V (possibly malignant and malignant) were higher than those for other classes. CONCLUSIONS: Sonographically based diagnosis may be helpful for detection of contralateral malignancy in preoperative patients with papillary thyroid microcarcinoma.

Comparison of T stage, N stage, multifocality, and bilaterality in papillary thyroid carcinoma patients according to the presence of coexisting lymphocytic thyroiditis.

PURPOSE: This study aimed to assess the relationship between coexisting lymphocytic thyroiditis and T-N stages of papillary thyroid carcinoma (PTC) by histopathological analysis. MATERIALS AND METHODS: The study included 653 patients who underwent thyroid surgery for PTC at our hospital. Each case was classified as either Hashimoto's thyroiditis (HT), non-Hashimoto type of lymphocytic thyroiditis (NHLT), or normal according to the histopathology of thyroid parenchyma. Patient age, gender, surgical modality, location, T stage, N stage, multifocality and bilaterality were compared according to the histopathology. RESULTS: The prevalence of coexisting lymphocytic thyroiditis was 25.8% (169/653); HT (7.5%, 49/653) and NHLT (18.3%, 120/653). There were no significant differences in T stage, N stage, multifocality and bilaterality with regard to coexisting lymphocytic thyroiditis, regardless of whether HT and NHLT were considered collectively or discretely. Primary tumor size (p < 0.0001), location (p = 0.0011), N stage (p < 0.0001), multifocality (p < 0.0001) and bilaterality (p < 0.0001) differed significantly according to T stage, and gender (p = 0.0193), primary tumor size (p < 0.0001), T stage (p < 0.0001), multifocality (p < 0.0001) and bilaterality (p < 0.0001) differed significantly according to N stage. CONCLUSIONS: PTC patients with coexisting lymphocytic thyroiditis did not differ from those with normal parenchyma in terms of T stage, N stage, multifocality and bilaterality.

Factors associated with postoperative hypothyroidism after lobectomy in papillary thyroid microcarcinoma patients.

PURPOSE: No previous study regarding the correlation between post-operative thyroid function and underlying thyroid histopathology has been published. This study assessed the relationship between postoperative thyroid function after lobectomy and multiple factors in papillary thyroid microcarcinoma (PTMC) patients. MATERIALS AND METHODS: From January 2010 to December 2010, 338 patients who had undergone thyroid lobectomy for PTMC were enrolled. Patients with pre-operative hyperthyroidism or those with hypothyroidism but no pre-operative serological data were excluded, leaving a cohort of 285 patients. The relationships between post-operative thyroid function (based on successful cessation of thyroxine replacement therapy) and multiple factors (patient age and sex, serological data, the Pre-operative anteroposterior diameter of the thyroid gland, underlying histopathology of the thyroid gland, and number of attempts to stop thyroxine replacement therapy) were analyzed. RESULTS: Out of 285 patients, 157 attempted to stop thyroxine replacement therapy once or twice after lobectomy; 91 successfully stopped thyroxine replacement therapy during the study period. The final histopathologic diagnoses after surgery included Hashimoto's thyroiditis (n = 5), non-Hashimoto type of lymphocytic thyroiditis (n = 17), and normal thyroid parenchyma (n = 135). Pre-operative thyroid-stimulating hormone (TSH) levels differed significantly between patients with postoperative hypothyroidism and those with postoperative euthyroidism (univariate logistic regression analysis, p = 0.0028; multivariate logistic regression analysis, p = 0.0029). No statistically significant differences were found for any other factors. CONCLUSIONS: The study results demonstrated that the Pre-operative TSH level was the only predictor for the development of post-operative hypothyroidism after thyroid lobectomy in PTMC patients.

Impact of international variation of prostate cancer on a predictive nomogram for biochemical recurrence in clinically localised prostate cancer.

OBJECTIVE: Prostate cancer (PCa) incidence has been rising rapidly in Korea with aggressive clinicopathologic features compared to those observed in Western countries. Our aim was to develop a predictive nomogram for BCR-free survival based on the characteristics of PCa in Korean men and compared its predictive accuracy to an established Western nomogram. METHODS: A nationwide multicenter study was designed involving 723 Korean men with clinically localised PCa that had undergone radical prostatectomy. The Cox proportional hazards model was applied to 549 cases from four heavy volume institutions to define prognostic factors and develops the Korean nomogram, which was subjected to internal validation, external validation using a separate cohort of 295 cases, and head-to-head comparison with the updated Kattan nomogram. RESULTS: During the mean follow-up period of 44.8 months, BCR occurred in 251 patients (35.4 %) with aggressive clinicopathologic features. Similar to Western cases, preoperative prostate-specific antigen (PSA), pathologic tumour stage (pT), and Gleason score (GS) were independent prognostic factors and used to develop the Korean nomogram in conjunction with age and surgical margin status. The Korean nomogram performed well for predicting BCR-free 5- and 10-year survival on internal validation. On external validation, the Korean nomogram showed better calibration than the updated Kattan nomogram. CONCLUSIONS: Preoperative PSA, pT, and GS were independent prognostic factor for BCR in clinically localised PCa in Korean men. The superior performance of the Korean nomogram for Korean PCa patients suggests that geographic variation in clinicopathologic factors should be considered in a predictive nomogram.