Sensitive photo-thermal response of graphene oxide for mid-infrared detection

This study characterizes the effects of incident infrared (IR) radiation on the electrical conductivity of graphene oxide (GO) and examines its potential for mid-IR detection. Analysis of the mildly reduced GO (m-GO) transport mechanism near room temperature reveals variable range hopping (VRH) for the conduction of electrons. This VRH behavior causes the m-GO resistance to exhibit a strong temperature dependence, with a large negative temperature coefficient of resistance of approximately -2 to -4% K(-1). In addition to this hopping transport, the presence of various oxygen-related functional groups within GO enhances the absorption of IR radiation significantly. These two GO material properties are synergically coupled and provoke a remarkable photothermal effect within this material; specifically, a large resistance drop is exhibited by m-GO in response to the increase in temperature caused by the IR absorption. The m-GO bolometer effect identified in this study is different from that exhibited in vanadium oxides, which require added gold-black films that function as IR absorbers owing to their limited IR absorption capability.

Applying Ultrasound-Guided Core Needle Biopsy for Diagnosis of Thyroid Masses: Preliminary Results From a Single Institution

OBJECTIVES

The purpose of this study was to investigate the level of conclusive results obtained with ultrasound (US)-guided core needle biopsy (CNB) and how this method should be applied for diagnosis of thyroid nodules.

METHODS

From January 2013 to November 2014, US-guided CNB was performed in 84 thyroid lesions of 83 patients. Based on CNB pathologic reports, thyroid nodules were divided into 2 categories: conclusive (nodules reaching a definite pathologic diagnosis suggesting benignity or malignancy) and inconclusive (nodules that were not able to reach a definite diagnosis because of ambiguous results). Medical records and US examinations were reviewed and compared.

RESULTS

The mean age of the 83 patients ± SD was 49.7 ± 14.1 years. Of the 84 thyroid nodules, 73 (86.9%) were diagnosed as benign or malignant and 11 (13.1%) as inconclusive by CNB pathologic analysis. Among the 11 nodules with inconclusive results, the possibility of a follicular neoplasm was suggested in 8 nodules (72.7%). No significant difference was seen in tumor size and US features when comparing the nodules with conclusive and inconclusive results (all P >.05).

CONCLUSIONS

Ultrasound-guided CNB may have supplemental roles in addition to US-guided fine-needle aspiration for diagnosis of selected cases. A considerable proportion of inconclusive results are seen on US-guided CNB, especially for diagnosis of follicular lesions, which must be considered when using this method for diagnosis of thyroid nodules.

A New Histone Deacetylase Inhibitor, MHY219, Inhibits the Migration of Human Prostate Cancer Cells via HDAC1

Histone deacetylase (HDAC) inhibitors are considered novel agents for cancer chemotherapy. We previously investigated MHY219, a new HDAC inhibitor, and its potent anticancer activity in human prostate cancer cells. In the present study, we evaluated MHY219 molecular mechanisms involved in the regulation of prostate cancer cell migration. Similar to suberanilohydroxamic acid (SAHA), MHY219 inhibited HDAC1 enzyme activity in a dose-dependent manner. MHY219 cytotoxicity was higher in LNCaP (IC₅₀=0.67 μM) than in DU145 cells (IC₅₀=1.10 μM) and PC3 cells (IC₅₀=5.60 μM) after 48 h of treatment. MHY219 significantly inhibited the HDAC1 protein levels in LNCaP and DU145 cells at high concentrations. However, inhibitory effects of MHY219 on HDAC proteins levels varied based on the cell type. MHY219 significantly inhibited LNCaP and DU145 cells migration by down-regulation of matrix metalloprotease-1 (MMP-1) and MMP-2 and induction of tissue inhibitor of metalloproteinases-1 (TIMP-1). These results suggest that MHY219 may potentially be used as an anticancer agent to block cancer cell migration through the repression of MMP-1 and MMP-2, which is related to the reduction of HDAC1.

Breast Microcalcifications: Diagnostic Outcomes According to Image-Guided Biopsy Method

OBJECTIVE

To evaluate the diagnostic outcomes of ultrasonography-guided core needle biopsy (US-CNB), US-guided vacuum-assisted biopsy (US-VAB), and stereotactic-guided vacuum-assisted biopsy (S-VAB) for diagnosing suspicious breast microcalcification.

MATERIALS AND METHODS

We retrospectively reviewed 336 cases of suspicious breast microcalcification in patients who subsequently underwent image-guided biopsy. US-CNB was performed for US-visible microcalcifications associated with a mass (n = 28), US-VAB for US-visible microcalcifications without an associated mass (n = 59), and S-VAB for mammogram-only visible lesions (n = 249). Mammographic findings, biopsy failure rate, false-negative rate, and underestimation rate were analyzed. Histological diagnoses and the Breast Imaging Reporting and Data System (BI-RADS) categories were reported.

RESULTS

Biopsy failure rates for US-CNB, US-VAB, and S-VAB were 7.1% (2/28), 0% (0/59), and 2.8% (7/249), respectively. Three false-negative cases were detected for US-CNB and two for S-VAB. The rates of biopsy-diagnosed ductal carcinoma in situ that were upgraded to invasive cancer at surgery were 41.7% (5/12), 12.9% (4/31), and 8.6% (3/35) for US-CNB, US-VAB, and S-VAB, respectively. Sonographically visible lesions were more likely to be malignant (66.2% [51/77] vs. 23.2% [46/198]; p < 0.001) or of higher BI-RADS category (61.0% [47/77] vs. 22.2% [44/198]; p < 0.001) than sonographically invisible lesions.

CONCLUSION

Ultrasonography-guided vacuum-assisted biopsy is more accurate than US-CNB when suspicious microcalcifications are detected on US. Calcifications with malignant pathology are significantly more visible on US than benign lesions.

Adding Ultrasound to the Evaluation of Patients with Pathologic Nipple Discharge to Diagnose Additional Breast Cancers: Preliminary Data

The aim of this study was to assess the malignancy yield of ultrasound Breast Imaging Reporting and Data System (BI-RADS) classification and the diagnostic value of adding ultrasound to diagnosis of breast cancer in patients with pathologic nipple discharge. Of 267 patients with pathologic nipple discharge seen from February 2003 to March 2011, 198 with histopathologic confirmation and follow-up data were included. Ultrasound images and mammograms were analyzed according to BI-RADS. The malignancy rate for each BI-RADS category and the difference in diagnostic performance resulting from the addition of ultrasound to mammography were calculated. Of the 198 enrolled patients, 34 were diagnosed with a malignancy. The malignancy rates obtained with the addition of ultrasound to mammography were 0.0% (0 of 27) for category 1, 5.9% (1/17) for category 2, 9.4% (5/53) for category 3, 21.5% (20/93) for category 4 and 100% (8/8) for category 5. The malignancy rates for mammography alone were 7.7%-9.0% for categories 1-3, 68.5% (13/19) for category 4 and 100.0% (5/5) for category 5. Adding US to mammography did not significantly increase sensitivity compared with mammography alone. Other diagnostic performance markers such as specificity and positive predictive value were not improved. Among patients for whom mammograms were available, ultrasound detected 5 breast cancers (26.3%) in addition to the 19 breast cancers found by positive mammography. Although it did not increase overall diagnostic performance in patients with pathologic nipple discharge, addition of ultrasound to mammography did detect an additional 26.3% of malignant lesions.

Cerebral Microbleeds in Patients with Dementia with Lewy Bodies and Parkinson Disease Dementia

BACKGROUND AND PURPOSE

The burden of amyloid β is greater in patients with dementia with Lewy bodies than in those with Parkinson disease dementia, and an increased amyloid β load is closely related to a higher incidence of cerebral microbleeds. Here, we investigated the prevalence and topography of cerebral microbleeds in patients with dementia with Lewy bodies and those with Parkinson disease dementia to examine whether cerebral microbleeds are more prevalent in patients with dementia with Lewy bodies than in those with Parkinson disease dementia.

MATERIALS AND METHODS

The study population consisted of 42 patients with dementia with Lewy bodies, 88 patients with Parkinson disease dementia, and 35 controls who underwent brain MR imaging with gradient recalled-echo. Cerebral microbleeds were classified as deep, lobar, or infratentorial.

RESULTS

The frequency of cerebral microbleeds was significantly greater in patients with dementia with Lewy bodies (45.2%) than in those with Parkinson disease dementia (26.1%) or in healthy controls (17.1%; P = .017). Lobar cerebral microbleeds were observed more frequently in the dementia with Lewy bodies group (40.5%) than in the Parkinson disease dementia (17%; P = .004) or healthy control (8.6%; P = .001) group, whereas the frequencies of deep and infratentorial cerebral microbleeds did not differ among the 3 groups. Logistic regression analyses revealed that, compared with the healthy control group, the dementia with Lewy bodies group was significantly associated with the presence of lobar cerebral microbleeds after adjusting for age, sex, nonlobar cerebral microbleeds, white matter hyperintensities, and other vascular risk factors (odds ratio, 4.39 [95% CI, 1.27-15.25]). However, compared with the healthy control group, the Parkinson disease dementia group was not significantly associated with lobar cerebral microbleeds.

CONCLUSIONS

This study showed that patients with dementia with Lewy bodies had a greater burden of cerebral microbleeds and exhibited a lobar predominance of cerebral microbleeds than did patients with Parkinson disease dementia.

The follicular variant of papillary thyroid carcinoma: characteristics of preoperative ultrasonography and cytology

PURPOSE

The goal of this study was to validate the ultrasonography (US) and cytopathological features that are used in the diagnosis of the follicular variant of papillary thyroid carcinoma (FVPTC) and to characterize the role of BRAF (V600E) mutation analysis in the diagnosis of FVPTC.

METHODS

From May 2012 to February 2014, 40 thyroid nodules from 40 patients (mean age, 56.2 years; range, 26 to 81 years) diagnosed with FVPTC were included in this study. The US features of the nodules were analyzed and the nodules were classified as probably benign or suspicious for malignancy. Twenty-three thyroid nodules (57.5%) underwent BRAF (V600E) mutation analysis. Clinical information and histopathologic results were obtained by reviewing the medical records of the patients.

RESULTS

Thirty nodules (75.0%) were classified as suspicious for malignancy, while 10 (25.0%) were classified as probably benign. Seven of the eight nodules (87.5%) with atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) cytology showed suspicious US features, while one of the two nodules (50.0%) with follicular neoplasm cytology presented suspicious US features. Five of the 23 nodules (21.7%) that underwent BRAF (V600E) mutation analysis had positive results, all of which were diagnosed as suspicious for malignancy or malignant based on cytology. None of the nodules with benign, AUS/FLUS, or follicular neoplasm cytology were positive for the BRAF (V600E) mutation.

CONCLUSION

US features allow nodules to be classified as suspicious for malignancy, and the presence of suspicious US features in nodules with ambiguous cytology may aid in the diagnosis of FVPTC. BRAF (V600E) mutation analysis is of limited value in the diagnosis of FVPTC.

Real-Time PCR Cycle Threshold Values for the BRAFV600E Mutation in Papillary Thyroid Microcarcinoma May Be Associated With Central Lymph Node Metastasis: A Retrospective Study

Papillary thyroid microcarcinoma (PTMC) usually has excellent prognosis, but a small subset shows aggressive behavior. Although the B-Raf proto-oncogene, serine/threonine kinase (BRAF)V600E mutation is the most common oncogenic alteration in PTMCs, it is frequently heterogeneously distributed within tumors. The aim of this study was to investigate the association of the BRAFV600E mutation found in fine needle aspirates from PTMCs with known clinicopathologic prognostic factors, based on both its presence and a quantitative approach that uses cycle threshold (Ct) values obtained by a real-time PCR technique. The 460 PTMC patients were included, with 367 patients having the BRAFV600E mutation. Clinicopathologic variables were compared between patients with and without the BRAFV600E mutation. BRAFV600E Ct values were compared according to clinicopathologic prognostic factors. Multivariate analyses were performed to evaluate factors predicting extrathyroidal extension and central and lateral lymph node metastasis (LNM). Each analysis used either the BRAFV600E mutation status or the Ct value as an independent variable for all the study patients and the 367 BRAFV600E-positive patients. Receiver-operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic performance of BRAFV600E Ct values in predicting central and lateral LNM. The BRAFV600E mutation status was not associated with clinicopathologic prognostic factors among the 460 PTMC patients. Of the 367 BRAFV600E-positive patients, Ct values were significantly lower in patients with central and lateral LNM (P < 0.001, P = 0.007). The Ct value was the only independent factor to predict central LNM (OR 0.918, P = 0.025). The area under the ROC curve (AUC) for diagnosing central LNM was 0.623 (sensitivity, 50.0%; specificity, 71.9%) and for diagnosing lateral LNM, it was 0.796 (sensitivity, 71.4%; specificity, 94.7%). In conclusion, real-time PCR Ct values for the BRAFV600E mutation obtained from fine needle aspirates can be associated with central LNM in PTMC patients. Although BRAFV600E Ct values did not reach statistical significance for predicting lateral LNM in our study, further validation through larger studies can be used to overcome any possible type-II errors. With further studies, Ct values for the BRAFV600E mutation obtained from fine needle aspirates may have important implications for predicting both central and lateral LNM in patients with PTMCs.

RAS Mutations in AUS/FLUS Cytology: Does it Have an Additional Role in BRAFV600E Mutation-Negative Nodules?

The object of this study is to evaluate the additional role of RAS mutation in detecting thyroid malignancy among BRAF mutation-negative nodules diagnosed as atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) on cytology.From December 2009 to December 2011, 202 BRAF mutation-negative thyroid nodules diagnosed as AUS/FLUS cytology in 201 patients were included in this study. RAS mutation analysis was performed using residual material from ultrasonography-guided fine needle aspiration (US-FNA) cytology testing for K-RAS, N-RAS, and H-RAS codons 12/13 and 61 point mutations. The authors evaluated the association between RAS mutation status and cytopathologic characteristics.Of the 202 BRAF mutation-negative thyroid nodules with AUS/FLUS cytology, 4 were considered insufficient for mutation analysis. Of the 198 thyroid nodules, 148 (74.7%) were confirmed as benign and 50 (25.3%) as malignant. Thirty-one (15.7%) of the 198 thyroid nodules were positive for any RAS mutation, 4 positive for K-RAS 12/13, 26 for N-RAS 61, and 1 positive for H-RAS 61. Seven (22.6%) of the RAS mutation positive nodules were malignant, 1 with K-RAS 12/13, 6 with N-RAS 61. Twenty-four (77.4%) of the 31 nodules positive for K-RAS 12/13 (N = 3), N-RAS 61 (N = 20), or H-RAS 61 (N = 1) mutations were proven benign. None of the 198 thyroid nodules were positive for K-RAS 61, N-RAS 12/13, or H-RAS 12/13 mutations.N-RAS 61 mutation is the most common mutation detected among BRAF mutation-negative nodules with AUS/FLUS cytology. RAS mutation has limited value in predicting malignancy among BRAF mutation-negative thyroid nodules with AUS/FLUS cytology and further, investigation is anticipated to evaluate the true role of RAS mutation in thyroid malignancy.

Association between information provision and decisional conflict in cancer patients

BACKGROUND

In this study, we aimed to identify demographic and clinical variables that correlate with perceived information provision among cancer patients and determine the association of information provision with decisional conflict (DC).

PATIENTS AND METHODS

We enrolled a total of 625 patients with cancer from two Korean hospitals in 2012. We used the European Organization for Research and Treatment of Cancer (EORTC) quality-of-life questionnaire (QLQ-INFO26) to assess patients' perception of the information received from their doctors and the Decisional Conflict Scale (DCS) to assess DC. To identify predictive sociodemographic and clinical variables for adequate information provision, backward selective logistic regression analyses were conducted. In addition, adjusted multivariate logistic regression analyses were carried out to identify clinically meaningful differences of perceived level of information subscales associated with high DC.

RESULTS

More than half of patients with cancer showed insufficient satisfaction with medical information about disease (56%), treatment (73%), other services (83%), and global score (80%). In multiple logistic regression analyses, lower income and education, female, unmarried status, type of cancer with good prognosis, and early stage of treatment process were associated with patients' perception of inadequate information provision. In addition, Information about the medical tests with high DCS values clarity [adjusted odds ratio (aOR), 0.54; 95% confidence interval (CI) 0.30-0.97] and support (aOR, 0.53; 95% CI 0.33-0.85) showed negative significance. For inadequate information perception about treatments and other services, all 5 DCS scales (uncertainty, informed, values clarity, support, and effective decision) were negatively related. Global score of inadequate information provision also showed negative association with high DCS effective decision (aOR, 0.43; 95% CI 0.26-0.71) and DCS uncertainty (aOR, 0.46; 95% CI 0.27-0.77).

CONCLUSION

This study found that inadequate levels of perceived information correlated with several demographic and clinical characteristics. In addition, sufficient perceived information levels may be related to low levels of DC.

Effectiveness and limitations of core needle biopsy in the diagnosis of thyroid nodules: review of current literature

Fine needle aspiration (FNA) is currently accepted as an easy, safe, and reliable tool for the diagnosis of thyroid nodules. Nonetheless, a proportion of FNA samples are categorized into non-diagnostic or indeterminate cytology, which frustrates both the clinician and patient. To overcome this limitation of FNA, core needle biopsy (CNB) of the thyroid has been proposed as an additional diagnostic method for more accurate and decisive diagnosis for thyroid nodules of concern. In this review, we focus on the effectiveness and limitations of CNB, and what factors should be considered when CNB is utilized in the diagnosis of thyroid nodules.

Thyroid incidentalomas detected on 18F-fluorodeoxyglucose-positron emission tomography/computed tomography: Thyroid Imaging Reporting and Data System (TIRADS) in the diagnosis and management of patients

BACKGROUND

Our aim was to evaluate the role of the Thyroid Imaging Reporting and Data System (TIRADS) in the risk stratification of thyroid incidentalomas detected on (18)F-fluorodeoxyglucose-positron emission tomography/computed tomography ((18)F-FDG-PET/CT) scans.

METHODS

Eighty-seven thyroid nodules in 84 patients showing incidentally detected increased uptake on (18)F-FDG-PET/CT who also had ultrasonography (US)-guided fine needle aspiration performed were included. On review of the US images, a TIRADS category was assigned to each thyroid nodule based on the number of suspicious US features. The correlation between the TIRADS category and the standard uptake values (SUV) on (18)F-FDG-PET/CT were calculated and compared.

RESULTS

Of the 87 thyroid nodules, 47 (54%) were benign, and 40 (46%) were malignant. The malignancy rate of the TIRADS categories were as follows: 9% for category 3, 15% for category 4a, 39% for category 4b, 72% for category 4c, and 100.0% for category 5. Combining the TIRADS with the SUV showed increased specificity and positive predictive value but decreased sensitivity and negative predictive value compared with TIRADS alone (all P < .05). The area under the receiver operating characteristics curve value of TIRADS was the greatest, comparable with the combined TIRADS and SUV (0.737 to 0.724, P = .788).

CONCLUSION

TIRADS may be applied in the risk stratification of thyroid incidentalomas detected on (18)F-FDG-PET/CT. Considering the high malignancy rate of thyroid incidentalomas showing increased (18)F-FDG uptake, ultrasonography-guided fine needle aspiration is mandatory even if there are no suspicious features present on US.

Fine-needle aspirate CYFRA 21-1, an innovative new marker for diagnosis of axillary lymph node metastasis in breast cancer patients

To compare the value of cytokeratin fragment 21-1 (CYFRA 21-1) concentration in the fine-needle biopsy aspirates (fine needle aspirate [FNA] CYFRA 21-1) with cytopathology of fine-needle aspiration biopsy (FNA cytology) and to assess whether CYFRA 21-1 concentrations from ultrasound-guided fine-needle aspiration biopsy (US-FNAB) specimens (FNA CYFRA 21-1) is not inferior to FNA cytology in the diagnosis of axillary lymph node (ALN) metastasis of breast cancer patients.This study received institutional review board approval, and written informed consent was obtained from all patients. US-FNAB was performed in 373 ALNs from 358 patients with invasive breast cancer. Concentrations of CYFRA 21-1 were measured from washouts of the syringe used during US-FNAB (FNA CYFRA 21-1), and ALN metastasis was determined using a cutoff value of 1.93 ng/mL. FNA cytology, intraoperative sentinel lymph node biopsy, and surgical pathology results were reviewed and analyzed. The noninferiority margin for the difference in accuracies between FNA cytology and FNA CYFRA 21-1 was set as 5%.Among 373 ALNs, 136 (36.5%) were benign, and 237 (63.5%) were metastatic. The mean FNA CYFRA 21-1 was significantly higher in metastatic ALNs compared to that in benign ALNs (P = 0.001). For the diagnosis of ALN metastasis, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FNA CYFRA 21-1 (cutoff value 1.93 ng/mL) were not significantly different from those of FNA cytology (P > 0.05). FNA CYFRA 21-1 reached statistical noninferiority to FNA cytology in terms of diagnostic accuracy for ALN metastasis. Of the 20 ALNs (8 metastasis, 12 benign) that showed insufficient results on FNA cytology, FNA CYFRA 21-1 accurately diagnosed 15 ALNs (4 metastasis, 11 benign).The diagnostic performance of FNA CYFRA 21-1 is comparable with that of FNA cytology for breast cancer ALN metastasis. Our results indicate that FNA CYFRA 21-1, using an US-FNAB specimen, can be a useful method equal to FNA cytology in terms of diagnostic accuracy.

What to do with thyroid nodules showing benign cytology and BRAF(V600E) mutation? A study based on clinical and radiologic features using a highly sensitive analytic method

BACKGROUND

BRAF(V600E) mutation analysis has been used as a complementary diagnostic tool to ultrasonography-guided, fine-needle aspiration (US-FNA) in the diagnosis of thyroid nodule with high specificity reported up to 100%. When highly sensitive analytic methods are used, however, false-positive results of BRAF(V600E) mutation analysis have been reported. In this study, we investigated the clinical, US features, and outcome of patients with thyroid nodules with benign cytology but positive BRAF(V600E) mutation using highly sensitive analytic methods from US-FNA.

METHODS

This study included 22 nodules in 22 patients (3 men, 19 women; mean age, 53 years) with benign cytology but positive BRAF(V600E) mutation from US-FNA. US features were categorized according to the internal components, echogenicity, margin, calcifications, and shape. Suspicious US features included markedly hypoechogenicity, noncircumscribed margins, micro or mixed calcifications, and nonparallel shape. Nodules were considered to have either concordant or discordant US features to benign cytology. Medical records and imaging studies were reviewed for final cytopathology results and outcomes during follow-up.

RESULTS

Among the 22 nodules, 17 nodules were reviewed. Fifteen of 17 nodules were malignant, and 2 were benign. The benign nodules were confirmed as adenomatous hyperplasia with underlying lymphocytic thyroiditis and a fibrotic nodule with dense calcification. Thirteen of the 15 malignant nodules had 2 or more suspicious US features, and all 15 nodules were considered to have discordant cytology considering suspicious US features. Five nodules had been followed with US or US-FNA without resection, and did not show change in size or US features on follow-up US examinations.

CONCLUSION

BRAF(V600E) mutation analysis is a highly sensitive diagnostic tool in the diagnosis of papillary thyroid carcinomas. In the management of thyroid nodules with benign cytology but positive BRAF(V600E) mutation, thyroidectomy should be considered in nodules which have 2 or more suspicious US features and are considered discordant on image-cytology correlation.

Switching bipolar hepatic radiofrequency ablation using internally cooled wet electrodes: comparison with consecutive monopolar and switching monopolar modes

OBJECTIVE

To evaluate whether switching bipolar radiofrequency ablation (SB-RFA) using three internally cooled wet (ICW) electrodes can induce coagulations >5 cm in porcine livers with better efficiency than consecutive monopolar (CM) or switching monopolar (SM) modes.

METHODS

A total of 60 coagulations were made in 15 in vivo porcine livers using three 17-gauge ICW electrodes and a multichannel radiofrequency (RF) generator. RF energy (approximately 200 W) was applied in CM mode (Group A, n = 20) for 24 min, SM mode for 12 min (Group B, n = 20) or switching bipolar (SB) mode for 12 min (Group C, n = 20) in in vivo porcine livers. Thereafter, the delivered RFA energy, as well as the shape and dimension of coagulations were compared among the groups.

RESULTS

Spherical- or oval-shaped ablations were created in 30% (6/20), 85% (17/20) and 90% (18/20) of coagulations in the CM, SM and SB groups, respectively (p = 0.003). SB-RFA created ablations >5 cm in minimum diameter (Dmin) in 65% (13/20) of porcine livers, whereas SM- or CM-RFA created ablations >5 cm in only 25% (5/20) and 20% (4/20) of porcine livers, respectively (p = 0.03). The mean Dmin of coagulations was significantly larger in Group C than in Groups A and B (5.1 ± 0.9, 3.9 ± 1.2 and 4.4 ± 1.0 cm, respectively, p = 0.002) at a lower delivered RF energy level (76.8 ± 14.3, 120.9 ± 24.5 and 114.2 ± 18.3 kJ, respectively, p < 0.001).

CONCLUSION

SB-RFA using three ICW electrodes can create coagulations >5 cm in diameter with better efficiency than do SM- or CM-RFA.

ADVANCES IN KNOWLEDGE

SB-RFA can create large, regular ablation zones with better time-energy efficiency than do CM- or SM-RFA.

Thyroid Nodules: Nondiagnostic Cytologic Results according to Thyroid Imaging Reporting and Data System before and after Application of the Bethesda System

PURPOSE

To compare the malignancy rates and the effectiveness of the Thyroid Imaging Reporting and Data System (TIRADS) for risk stratification of nodules with nondiagnostic results classified before and after application of the Bethesda System for Reporting Thyroid Cytopathology.

MATERIALS AND METHODS

This retrospective study was approved by an institutional review board, with waiver of informed consent. A total of 763 patients with 790 thyroid nodules and nondiagnostic cytologic results were included (mean age ± standard deviation, 52.3 years ± 11.5), 485 nodules from the pre-Bethesda period (from March 2007 to December 2008) and 305 nodules from the post-Bethesda period (from May 2011 to May 2012). A TIRADS category was assigned to each thyroid nodule on the basis of the number of features that appeared suspicious for cancer at ultrasonography (US). Malignancy rates and TIRADS categories during the two periods were compared. Correlation between TIRADS category and malignancy risk between the two periods was evaluated and compared.

RESULTS

The malignancy rates of nodules with nondiagnostic cytologic results were not significantly different between the two periods (P = .148). Malignancy risk of TIRADS category 3, 4a, 4b, 4c, and 5 was 1.8%, 5.7%, 4.1%, 29.8%, and 16.7%, for the pre-Bethesda period, and 1.6%, 3.0%, 7.1%, 16.3%, and 25.0% for the post-Bethesda period, respectively. Near-perfect correlation was seen between the TIRADS category and malignancy risk in the post-Bethesda period (r = 0.961, P = .009), while no significant correlation was found in the pre-Bethesda period (r = 0.731, P = .161).

CONCLUSION

Malignancy risk stratification with TIRADS was more effective for nodules with nondiagnostic cytologic results classified according to the Bethesda System. When these Bethesda-classified nodules with nondiagnostic results are evaluated as TIRADS category 3 or 4a, they may be treated conservatively with follow-up US, but when other cytologic classifications are applied, follow-up US and fine- needle aspiration must be considered for nodules showing one or more features suspicious for cancer at US.

Malignancy risk and characteristics of thyroid nodules with two consecutive results of atypia of undetermined significance or follicular lesion of undetermined significance on cytology

PURPOSE

To evaluate the malignancy risk and characteristics of thyroid nodules with two "Atypia of Undetermined Significance" or "Follicular Lesion of Undetermined Significance" (AUS/FLUS) results, and compare characteristics of malignancies with two AUS/FLUS results to those with one AUS/FLUS result.

METHODS

Of 441 thyroid nodules with initial AUS/FLUS results, 236 underwent repeat fine-needle-aspiration (FNA), with 58 obtaining repeated AUS/FLUS results. Thyroid Imaging Reporting and Data System (TIRADS) categories were assigned, and clinico-pathological characteristics were compared between benign and malignant nodules and between malignancies with two consecutive AUS/FLUS results and those with one AUS/FLUS result.

RESULTS

Thirty-one percent (18/58) of nodules with two AUS/FLUS results and 58.1% (18/31) of confirmed nodules were malignant. Age, gender, nodule size, ultrasound features and TIRADS categories did not differ between benign and malignant nodules or between malignancies with one and two AUS/FLUS results. Malignancies with two AUS/FLUS results had a higher proportion of a follicular variant of papillary thyroid carcinoma (PTC) (46.7% vs. 13.6%, P = 0.009).

CONCLUSIONS

Thyroid nodules with two AUS/FLUS results had a high malignancy risk of at least 31.0% and a higher proportion of a follicular variant of PTC. Surgery should be considered regardless of ultrasound features.

KEY POINTS

• Thyroid nodules with two consecutive AUS/FLUS results had a high malignancy risk. • Ultrasound features are less useful in nodules with two AUS/FLUS results. • The follicular variant of PTC is more frequent in malignancies with two AUS/FLUS results.

Imaging surveillance of patients with breast cancer after primary treatment: current recommendations

Women who have been treated for breast cancer are at risk for second breast cancers, such as ipsilateral recurrence or contralateral metachronous breast cancer. As the number of breast cancer survivors increases, interest in patient management and surveillance after treatment has also increased. However, post-treatment surveillance programs for patients with breast cancer have not been firmly established. In this review, we focus on the imaging modalities that have been used in post-treatment surveillance for patients with breast cancer, such as mammography, ultrasonography, magnetic resonance imaging, and positron emission tomography, the effectiveness of each modality for detecting recurrence, and how they can be applied to manage patients.

Evaluation of malignancy risk stratification of microcalcifications detected on mammography: a study based on the 5th edition of BI-RADS

BACKGROUND

The 5th edition of Breast Imaging Reporting and Data System subdivides suspicious calcifications into two categories: 4B-amorphous, coarse heterogeneous, and fine pleomorphic calcifications; 4C-fine linear or fine linear branching calcifications. We investigated whether these revised categories are appropriate for malignancy risk stratification.

METHODS

We studied 246 patients (mean age 48.2 years) with suspicious microcalcifications detected on mammography who underwent stereotactic biopsy (n = 154) or surgical excisional biopsy with preoperative mammogram-guided needle localization (n = 92). Pre-biopsy mammograms were reviewed retrospectively, and imaging features were analyzed according to the revised morphology and distribution descriptors. Pathological results of stereotactic biopsy and surgical excision were considered, with the surgical results being the reference standard. Positive predictive values (PPVs) were calculated and compared using the χ (2) test or Fisher's exact test.

RESULTS

Overall PPV of suspicious microcalcifications was 22.4 %. PPVs of morphology descriptors were as follows: amorphous 7.9 %, coarse heterogeneous 17.8 %, fine pleomorphic 63.2 %, fine linear/fine linear branching 100 % (p < 0.001). PPVs of distribution descriptors were as follows: regional 8.8 %, grouped 14.3 %, linear 87.5 %, segmental 63.6 % (p < 0.001). For morphology and distribution descriptors combinations, PPVs for amorphous/regional and amorphous/grouped microcalcifications were 4.2 and 7.6 %, resepectively. The PPV for fine pleomorphic/linear or segmental was 93.8 %.

CONCLUSIONS

Subcategorization of morphology descriptors for suspicious microcalcifications is needed because of the different PPVs for amorphous, coarse heterogeneous, and fine pleomorphic microcalcifications. Combining morphology and distribution descriptors for suspicious microcalcifications provides accurate risk stratification.

Percutaneous ultrasound-guided vacuum-assisted removal versus surgery for breast lesions showing imaging-histology discordance after ultrasound-guided core-needle biopsy

Objective

To evaluate the upgrade rate and delayed false-negative results of percutaneous vacuum-assisted removal (VAR) and surgical excision in women with imaging-histologic discordance during ultrasound (US)-guided automated core needle biopsy (CNB) of the breast and to validate the role of VAR as a rebiopsy method for these discordant lesions.

Materials and Methods

Percutaneous US-guided 14-gauge CNB was performed on 7470 patients between August 2005 and December 2010. Our study population included 161 lesions in 152 patients who underwent subsequent rebiopsy due to imaging-histologic discordance. Rebiopsy was performed using VAR (n = 88) or surgical excision (n = 73). We investigated the upgrade rate immediately after rebiopsy and delayed false-negative results during at least 24 months of follow-up after rebiopsy. We also evaluated the clinicoradiological differences between VAR and surgical excision.

Results

Total upgrade to malignancy occurred in 13.7% (22/161) of lesions at rebiopsy including both VAR and surgical excision: 4.6% (4/88) of VAR cases (4/88) and 24.7% (18/73) of surgical excision cases (p < 0.001). Surgical excision was performed significantly more frequently in older patients and for larger-sized lesions than that of VAR, and a significant difference was detected between VAR and surgical excision in the Breast Imaging and Reporting and Data System category (p < 0.007). No delayed false-negative results were observed after VAR or surgical excision during the follow-up period.

Conclusion

Long-term follow-up data showed no delayed cancer diagnoses after US-guided VAR in imaging-histologic discordant lesions of the breast, suggesting that VAR might be a rebiopsy method for these lesions.

Can increased tumoral vascularity be a quantitative predicting factor of lymph node metastasis in papillary thyroid microcarcinoma?

The aim of the present study was to evaluate the clinical implications of the vascular index (VI) as a predicting factor for central and lateral lymph node metastasis (LNM) in patients with papillary thyroid microcarcinoma (PTMC). From January 2011 to October 2011, 588 patients (495 females, 93 males) who were diagnosed with PTMC were included. Clinicopathologic characteristics of patients and ultrasound (US) features of the lesions including VI were evaluated retrospectively. The VI was measured with QLAB 7.0 quantification software using preoperative Doppler US images. Univariate and multivariate analysis were used to assess predictive factors of LNM. From 588 patients, 140 patients (23.8 %) had central LNM and 26 patients (4.4 %) had lateral LNM on pathologic results. The presence of lateral LNM [odds ratio (OR) 5.46; 95 % confidence interval (CI) = 2.19-13.64], bilaterality (OR 2.16; 95 % CI 1.17-4.01), and increased tumor size (OR 1.15; 95 % CI 1.04-1.28) were significant independent factors for predicting central LNM. The presence of central LNM (OR 5.58; 95 % CI 2.22-14.04), upper third location of malignancy (OR 2.50; 95 % CI 1.01-6.21), and tumor size (OR 1.34; 95 % CI 1.03-1.73) were significant independent factors for predicting lateral LNM. However, the VI was not a significant predicting factor for both central and lateral LNM. Therefore, the VI of PTMC may not be useful for predicting central and lateral LNM in patients with PTMC.

Malignancy risk stratification in thyroid nodules with nondiagnostic results at cytologic examination: combination of thyroid imaging reporting and data system and the Bethesda System

PURPOSE

To evaluate the malignancy risks of thyroid nodules with nondiagnostic results at ultrasonography (US)-guided fine-needle aspiration biopsy ( FNAB fine-needle aspiration biopsy ) and the criteria for selecting those for repeat US-guided FNAB fine-needle aspiration biopsy according to the thyroid imaging reporting and data system ( TIRADS thyroid imaging reporting and data system ).

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board, and the requirement to obtain informed consent was waived. Five hundred forty-eight nondiagnostic nodules were included. US features of internal composition, echogenicity, margin, calcifications, shape, and vascularity were evaluated, and thyroid nodules were classified according to TIRADS thyroid imaging reporting and data system . TIRADS thyroid imaging reporting and data system category 3 included nodules without any suspicious features of solidity, hypoechogenicity or marked hypoechogenicity, microlobulated or irregular margins, microcalcifications, and taller-than-wide shape. Categories 4a, 4b, 4c, and 5 included nodules with one, two, three or four, or five suspicious US features. The malignancy risk was calculated.

RESULTS

Of the 548 nodules, 40 (7.3%) were malignant and 508 (92.7%) were benign. The malignancy risks of categories 3 and 4a nodules were 0.8% and 1.8%, respectively, whereas the malignancy risks of categories 4b, 4c, and 5 nodules were 6.1%, 14.4%, and 31%. In the 294 nodules larger than 10 mm, the malignancy risks of categories 3, 4a, 4b, 4c, and 5 nodules were 0.9%, 1.3%, 0%, 15%, and 33%, respectively. In the 254 nodules measuring 10 mm or smaller, the malignancy risks of categories 3, 4a 4b, 4c, and 5 nodules were 0%, 2.7%, 14%, 14.3%, and 31%.

CONCLUSION

Nondiagnostic thyroid nodules without suspicious US features and those with one suspicious feature can be followed up with US, but nondiagnostic nodules with two or more suspicious features should undergo repeat US-guided FNAB fine-needle aspiration biopsy.

Estimation of size of cord blood inventory based on high-resolution typing of HLAs

Methods for estimating the cord blood (CB) inventory size required vary according to the ethnic diversity of the HLA, degree of HLA matching and HLA-typing resolution. We estimated the CB inventory size required using 7190 stored CB units (CBU) and 2450 patients who were awaiting or underwent allogeneic hematopoietic stem cell transplantation. With high-resolution typing of HLA-A, B and DRB1, 94.6% of Korean patients could find CBUs in 100 000 CBUs with a 5/6 match, and 95.7% could find CBUs in 5000 CBUs with a 4/6 match. With low-resolution typing of HLA-A and B and high-resolution typing of leukocyte antigen-DRB1, 95% of patients could find CBUs in 50 000 CBUs with a 5/6 match, and 96.7% could find CBUs in 3000 CBUs  with a 4/6 match. With additional high-resolution typing for HLA-A and B, which could improve transplantation outcome, the size of the CB inventory would need to increase twofold for Koreans.

The effectiveness of a brochure describing an acceptable method of sputum collection for tuberculosis testing

We evaluated the effectiveness of an educational brochure explaining proper sputum collection techniques for tuberculosis (TB) diagnosis. Patients with suspected pulmonary TB (PTB) were randomly assigned to either the brochure-using group or the non-using group. No significant difference in positive TB culture rates was observed between the brochure-using and non-using groups (33.1% vs. 35.6%, P = 0.690). The proportions of acceptable specimen samples for bacterial pneumonia were also similar between the two groups (37.1% vs. 35.6%). An educational brochure provided by the attending physician explaining an acceptable specimen collection method for TB testing did not result in a higher detection rate of PTB.