Effects of military life on changes in body mass index of enlisted men: a cross-sectional study

Background

Obesity is a serious health problem with an incidence that is increasing rapidly. Enlisted men are a distinctive group characterised by 24-hour community-living and are likely to experience changes in body weight as a result of regular diet and exercise during enlistment.

Methods

This study reviewed data from the Second Military Health Survey. Changes in body mass index (BMI) before and during military service were analysed using paired t-test. We calculated OR and 95% CI for factors affecting weight improvement during military service through logistic regression.

Results

The mean BMI in the underweight group increased by 5.87 kg/m² during service, while that in the normal weight group increased by 1.18 kg/m². In contrast, the mean BMI in the overweight group decreased by 5.47 kg/m² during service. The OR for an improved BMI in the subjective good health group compared with the subjective poor health group was statistically significant (OR=1.71, 95% CI 1.02 to 2.87). The OR for an improved BMI was significantly higher in the group with three or more times per week of strength training than in the group with one to two times per week of strength training, and was higher among the marines compared with the Army soldiers (OR=1.48, 95% CI 1.03 to 2.12 and OR=2.15, 95% CI 1.07 to 4.32, respectively).

Conclusions

Strength training showed a statistically significant increase in BMI during military service. Furthermore, the BMI of men who were underweight before their service increased, while it decreased among those who were overweight.

First Experience in Korea of Stereotactic Partial Breast Irradiation for Low-Risk Early-Stage Breast Cancer

Purpose: Accelerated partial breast irradiation (A-PBI) in Korean women has been considered impracticable, owing to small breast volume and lack of high-precision radiotherapy experience. We present the first experience of stereotactic-PBI (S-PBI) with CyberKnife M6 to investigate feasibility of use and early toxicities in Korean women with early breast cancers.

Materials and Methods: A total of 104 breasts receiving S-PBI at our institution between September 2017 and October 2018 were reviewed. Patients were selected based on the American Society for Radiation Oncology (ASTRO), American Brachytherapy Society, American Society of Breast Surgeons, and Groupe Européen de Curiethérapie-European Society for Therapeutic Radiology and Oncology guidelines. A dose of 30 Gy in 5 fractions (NCT01162200) was used. Gold fiducials were routinely inserted near the tumor bed for tracking. Constraints regarding organs-at-risk followed the NSABP-B39/RTOG 0413 protocol.

Results: Median follow-up was for 13 months. Patients were categorized as “suitable” (71.2%) or “cautionary” (28.8%) according to 2017 the ASTRO guidelines. No tracking failure of inserted gold fiducials occurred. Median planning target volume (PTV) and PTV-to-whole breast volume ratio was 73.6 mL (interquartile range, 58.8–103.9 mL) and 17.0% (13.3–19.1%), respectively. Median PTV V_95%, PTV D_max, and ipsilateral breast V_50% were 97.8% (96.2–98.8%), 105.3% (104.2–106.4%), and 35.5% (28.3–39.8%), respectively. No immediate post-S-PBI toxicity ≥ grade 2 was reported, except grade 2 induration in three breasts. All patients remain disease-free to date.

Conclusion: The first use of S-PBI in Korean women was feasible and safe for selected early breast cancer. Based on these results, we have initiated a prospective study (NCT03568981) to test S-PBI in whole-breast irradiation for low-risk early breast cancer.

Factors Predicting Breast Cancer Development in Women During Surveillance After Surgery for Atypical Ductal Hyperplasia of the Breast: Analysis of Clinical, Radiologic, and Histopathologic Features

BACKGROUND

This study aimed to evaluate the risk of breast cancer development for women under surveillance after surgery for atypical ductal hyperplasia (ADH), as well as the clinical and pathologic factors associated with breast cancer development.

METHODS

From November 2003 to December 2014, the study included 205 women (mean age, 47.1 ± 11.2 years; range 18-73 years) with a pathologic diagnosis of ADH at surgical excision who had preoperative mammography and ultrasonography (US) images and pathology slides available for review. The patients were classified into three groups according to the detection method as follows: negative group (with ADH occult on imaging), mammography group (with ADH detected on mammography), and US group (with ADH detected on US only). Clinical, radiologic, and histopathologic factors associated with breast cancer development after ADH surgery were evaluated.

RESULTS

Breast cancer developed in 15 patients (7.3%) during surveillance after ADH surgery (follow-up period, 63.9 ± 40.8 months). Palpable lesions had significantly higher rates of breast cancer development after ADH surgery (26.7% vs 6.8%; P = 0.045). Breast cancer development after ADH surgery did not differ according to the detection method (P = 0.654). Palpability was significantly associated with breast cancer development during surveillance after ADH surgery (hazard ratio, 3.579; 95% confidence interval 1.048-12.220; P = 0.042).

CONCLUSION

The breast cancer development rate for women under surveillance after ADH surgery was 7.3%. Palpability at the time of ADH diagnosis was significantly associated with breast cancer development.

Scattering Studies with Low-Energy Kaon-Proton Femtoscopy in Proton-Proton Collisions at the LHC

The study of the strength and behavior of the antikaon-nucleon (K[over ¯]N) interaction constitutes one of the key focuses of the strangeness sector in low-energy quantum chromodynamics (QCD). In this Letter a unique high-precision measurement of the strong interaction between kaons and protons, close and above the kinematic threshold, is presented. The femtoscopic measurements of the correlation function at low pair-frame relative momentum of (K^{+}p⊕K^{-}p[over ¯]) and (K^{-}p⊕K^{+}p[over ¯]) pairs measured in pp collisions at sqrt[s]=5, 7, and 13 TeV are reported. A structure observed around a relative momentum of 58  MeV/c in the measured correlation function of (K^{-}p⊕K^{+}p[over ¯]) with a significance of 4.4σ constitutes the first experimental evidence for the opening of the (K[over ¯]^{0}n⊕K^{0}n[over ¯]) isospin breaking channel due to the mass difference between charged and neutral kaons. The measured correlation functions have been compared to Jülich and Kyoto models in addition to the Coulomb potential. The high-precision data at low relative momenta presented in this work prove femtoscopy to be a powerful complementary tool to scattering experiments and provide new constraints above the K[over ¯]N threshold for low-energy QCD chiral models.

MRI Radiomic Features: Association with Disease-Free Survival in Patients with Triple-Negative Breast Cancer

Radiomic features hold potential to improve prediction of disease-free survival (DFS) in triple-negative breast cancer (TNBC) and may show better performance if developed from TNBC patients. We aimed to develop a radiomics score based on MRI features to estimate DFS in patients with TNBC. A total of 228 TNBC patients who underwent preoperative MRI and surgery between April 2012 and December 2016 were included. Patients were temporally divided into the training (n = 169) and validation (n = 59) set. Radiomic features of the tumor were extracted from T2-weighted and contrast-enhanced T1- weighted MRI. Then a radiomics score was constructed with the least absolute shrinkage and selection operator regression in the training set. Univariate and multivariate Cox proportional hazards models were used to determine what associations the radiomics score and clinicopathologic variables had with DFS. A combined clinicopathologic-radiomic (CCR) model was constructed based on multivariate Cox analysis. The incremental values of the radiomics score were evaluated by using the integrated area under the receiver operating characteristic curve (iAUC) and bootstrapping (n = 1000). The radiomics score, which consisted of 5 selected MRI features, was significantly associated with worse DFS in both the training and validation sets (p = 0.002, p = 0.033, respectively). In both the training and validation set, the radiomics score showed comparable performance with the clinicopathologic model. The CCR model demonstrated better performance than the clinicopathologic model in the training set (iAUC, 0.844; difference in iAUC, p < 0.001) and validation set (iAUC, 0.765, difference in iAUC, p < 0.001). In conclusion, MRI-based radiomic features can improve the prediction of DFS when integrated with clinicopathologic data in patients with TNBC.

Pattern-based vs. score-based guidelines using ultrasound features have different strengths in risk stratification of thyroid nodules

OBJECTIVE

To evaluate and compare the diagnostic performances between recently published pattern-based and score-based TIRADS according to the experience level of the performer.

METHODS

From July 2013 to January 2019, 8657 thyroid nodules in 8364 patients that had been cytopathologically diagnosed as benign or malignant were included (mean size, 22.0 mm ± 12.1). Thyroid nodules were categorized into US-based final assessment categories and US-FNA indications of five recently published TIRADS. Radiologists performing the US examinations were divided into the experienced vs. inexperienced group. Diagnostic performances and unnecessary biopsy rates were calculated and compared between the five TIRADS, also the experienced vs. inexperienced group.

RESULTS

Of the 8657 thyroid nodules, 6706 (77.5%) were benign and 1951 (22.5%) were malignant. Diagnostic performances for US-based final assessment categories showed higher sensitivity and NPV for EU-TIRADS (92.7% and 96.5%), while Kwak-TIRADS had higher specificity, PPV, accuracy, and AUC (89.6%, 68.0%, 86.5%, and 0.878; all p < 0.05, respectively). Diagnostic performances for US-FNA indications showed higher sensitivity and NPV for KTA/KSThR TIRADS (98.5% and 97.0%), while Kwak-TIRADS had higher specificity, PPV, accuracy, and AUC (70.3%, 46.6%, 74.5%, and 0.797; all p < 0.05, respectively). Unnecessary biopsy rates were the lowest in Kwak-TIRADS for both US categories and US-FNA indications (32.0% and 53.4%, p < 0.001). Similar trends were seen in both the experienced and inexperienced group.

CONCLUSION

The currently published score-based guidelines for thyroid nodules have significantly higher specificity, PPV, accuracy, and AUC and lower unnecessary biopsy rates, whereas pattern-based guidelines have higher sensitivity and NPV, regardless of the level of experience of the performer.

KEY POINTS

• For US-based final assessment categories, EU-TIRADS had higher sensitivity and NPV, while Kwak-TIRADS had higher specificity, PPV, accuracy, and AUC. • For US-FNA indications, KTA/KSThR TIRADS had higher sensitivity and NPV, while Kwak-TIRADS had higher specificity, PPV, accuracy, and AUC. • Similar trends were seen in diagnostic performances for both experienced and inexperienced groups.

Radiomics in predicting mutation status for thyroid cancer: A preliminary study using radiomics features for predicting BRAFV600E mutations in papillary thyroid carcinoma

Purpose

To evaluate whether if ultrasonography (US)-based radiomics enables prediction of the presence of BRAF^V600E mutations among patients diagnosed as papillary thyroid carcninoma (PTC).

Methods

From December 2015 to May 2017, 527 patients who had been treated surgically for PTC were included (training: 387, validation: 140). All patients had BRAF^V600E mutation analysis performed on surgical specimen. Feature extraction was performed using preoperative US images of the 527 patients (mean size of PTC: 16.4mm±7.9, range, 10–85 mm). A Radiomics Score was generated by using the least absolute shrinkage and selection operator (LASSO) regression model. Univariable/multivariable logistic regression analysis was performed to evaluate the factors including Radiomics Score in predicting BRAF^V600E mutation. Subgroup analysis including conventional PTC <20-mm (n = 389) was performed (training: 280, validation: 109).

Results

Of the 527 patients diagnosed with PTC, 428 (81.2%) were positive and 99 (18.8%) were negative for BRAF^V600E mutation. In both total 527 cancers and 389 conventional PTC<20-mm, Radiomics Score was the single factor showing significant association to the presence of BRAF^V600E mutation on multivariable analysis (all P<0.05). C-statistics for the validation set in the total cancers and the conventional PTCs<20-mm were lower than that of the training set: 0.629 (95% CI: 0.516–0.742) to 0.718 (95% CI: 0.650–0.786), and 0.567 (95% CI: 0.434–0.699) to 0.729 (95% CI: 0.632–0.826), respectively.

Conclusion

Radiomics features extracted from US has limited value as a non-invasive biomarker for predicting the presence of BRAF^V600E mutation status of PTC regardless of size.

Core-Needle Biopsy Does Not Show Superior Diagnostic Performance to Fine-Needle Aspiration for Diagnosing Thyroid Nodules

PURPOSE

To compare the diagnostic performances of fine-needle aspiration (FNA) and core-needle biopsy (CNB) for thyroid nodules according to nodule size.

MATERIALS AND METHODS

This retrospective study included 320 thyroid nodules from 320 patients who underwent both FNA and CNB at outside clinics and proceeded with surgery in our institution between July 2012 and May 2019. According to nodule size, the diagnostic performances of FNA and CNB were calculated using various combinations of test-negatives and test-positives defined by the Bethesda categories and were compared using the generalized estimated equation and the Delong method.

RESULTS

There were 279 malignant nodules in 279 patients and 41 benign nodules in 41 patients. The diagnostic performance of FNA was mostly not different from CNB regardless of nodule size, except for negative predictive value, which was better for FNA than CNB when applying Criteria 1 and 2. When applying Criteria 3, the specificity and positive predictive value of FNA were superior to CNB regardless of size. When applying Criteria 4, diagnostic performance did not differ between FNA and CNB regardless of size. After applying Criteria 5, diagnostic performance did not differ between FNA and CNB in nodules ≥2 cm. However, in nodules ≥1 cm and all nodules, the sensitivity, accuracy, and negative predictive value of CNB were better than those of FNA.

CONCLUSION

CNB did not show superior diagnostic performance to FNA for diagnosing thyroid nodules.

Radiomics signature for prediction of lateral lymph node metastasis in conventional papillary thyroid carcinoma

Purpose

Preoperative neck ultrasound (US) for lateral cervical lymph nodes is recommended for all patients undergoing thyroidectomy for thyroid malignancy, but it is operator dependent. We aimed to develop a radiomics signature using US images of the primary tumor to preoperatively predict lateral lymph node metastasis (LNM) in patients with conventional papillary thyroid carcinoma (cPTC).

Methods

Four hundred consecutive cPTC patients from January 2004 to February 2006 were enrolled as the training cohort, and 368 consecutive cPTC patients from March 2006 to February 2007 served as the validation cohort. A radiomics signature, which consisted of 14 selected features, was generated by the least absolute shrinkage and selection operator (LASSO) regression model in the training cohort. The discriminating performance of the radiomics signature was assessed in the validation cohort with the area under the receiver operating characteristic curve (AUC).

Results

The radiomics signature was significantly associated with lateral cervical lymph node status (p < 0.001). The AUC of its performance in discriminating metastatic and non-metastatic lateral cervical lymph nodes was 0.710 (95% CI: 0.649–0.770) in the training cohort and was 0.621 (95% CI: 0.560–0.682) in the validation cohort.

Conclusions

The present study showed that US radiomic features of the primary tumor were associated with lateral cervical lymph node status. Although their discriminatory performance was slightly lower in the validation cohort, our study shows that US radiomic features of the primary tumor alone have the potential to predict lateral LNM.

P1603 Changes of cardiac function in cirrhotic patients after liver transplantation

Funding Acknowledgements

This study was supported by the grant of CJ healthcare 2016 research fund.

Background

Liver cirrhosis (LC) has been known to affect cardiovascular performance. Limited study have evaluated the alteration of myocardial function in patients with LC after liver transplantation (LT).

Purpose

The aim of study was to evaluate changes of cardiac function in patients with cirrhosis following LT using conventional and speckle-tracking echocardiography and late gadolinium enhancement (LGE) of cardiac magnetic resonance (MR).

Methods

Thirty-five patients with cirrhosis (mean age, 57.1 ± 9.0; male, 75%) who were listed for LT were prospectively enrolled. Patients underwent conventional, speckle-tracking echocardiography, and cardiac MR imaging with LGE. Echocardiography and cardiac MR were performed at pre and 1 year after LT. Cirrhotic patients were compared with normal control (n = 20, mean age, 65.0 ± 14.8; men, 11(55%)) and echocardiographic and cardiac MR data were compared pre and post LT.

Results

Conventional and speckle-tracking echocardiography and Cardiac MR imaging demonstrated hyperdynamic left ventricular (LV) function in patients with cirrhosis (LV ejection fraction (EF) with cardiac MR 67.8 ± 7.0% in LC vs. 63.4 ± 6.4% in control, P = 0.028; global longitudinal strain (GLS) -24.3 ± 2.6% in LC vs. -18.6 ± 2.2% in control, P &lt; 0.001). There were no LGE in patients with cirrhosis and no significant differences in LV size, LV wall thickness, LV mass index, and diastolic function between cirrhotic patients and control group (all P &gt; 0.1). Corrected QT interval (QTc) in electrocardiogram was prolonged in LC patients (P &lt; 0.001). One-year after LT, LV end-diastolic diameter and LV end-diastolic volume significantly decreased (P = 0.016 and 0.022, respectively). Although LVEF showed no significant changes 1 year post-LT (P = 0.362), LV-GLS (from -24.7 ± 1.8% to -20.8 ± 3.4%, P &lt; 0.001) significantly decreased. QTc interval also decreased 1 year after LT (from 470.4 ± 29.6msec to 428.2 ± 31.6msec, P = 0.001).

Conclusions

The present study demonstrated that cirrhotic patients showed hyperdynamic circulation and prolonged QTc interval compared with normal controls. After 1 year LT, LV size reduced and augmented LV function was normalized. Given that no LGE in cardiac MR and normalized GLS and QTc after LT, cardiac dysfunction in LC patients could be reversed by LT.

Application of Point Shearwave Elastography to Breast Ultrasonography: Initial Experience Using “S-Shearwave” in Differential Diagnosis

Purpose

To evaluate the optimal measurement location, cut-off value, and diagnostic performance of S-Shearwave in differential diagnosis of breast masses seen on ultrasonography (US).

Materials and Methods

During the study period, 225 breast masses in 197 women were included. S-Shearwave measurements were made by applying a square region-of-interest automatically generated by the US machine. Shearwave elasticity was measured three times at four different locations of the mass, and the highest shearwave elasticity was used for calculating the optimal cut-off value. Diagnostic performance was evaluated by using the area under the receiving operator characteristic curve (AUC).

Results

Of the 225 breast masses, 156 (69.3%) were benign and 69 (30.7%) were malignant. Mean S-Shearwave values were significantly higher for malignant masses (108.0 ± 70.0 kPa vs. 43.4 ± 38.3 kPa; p < 0.001). No significant differences were seen among AUC values at different measurement locations. With a cut-off value of 41.9 kPa, S-Shearwave showed 85.7% sensitivity, 63.9% specificity, 70.7% accuracy, and positive and negative predictive values of 51.7% and 90.8%, respectively. The AUCs for US and S-Shearwave did not show significant differences (p = 0.179).

Conclusion

S-Shearwave shows comparable diagnostic performance to that of grayscale US that can be applied for differential diagnosis of breast masses seen on US.

Measurement of ϒ(1S) Elliptic Flow at Forward Rapidity in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The first measurement of the ϒ(1S) elliptic flow coefficient (v_{2}) is performed at forward rapidity (2.5<y<4) in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the LHC. The results are obtained with the scalar product method and are reported as a function of transverse momentum (p_{T}) up to 15  GeV/c in the 5%-60% centrality interval. The measured ϒ(1S)v_{2} is consistent with 0 and with the small positive values predicted by transport models within uncertainties. The v_{2} coefficient in 2<p_{T}<15  GeV/c is lower than that of inclusive J/ψ mesons in the same p_{T} interval by 2.6 standard deviations. These results, combined with earlier suppression measurements, are in agreement with a scenario in which the ϒ(1S) production in Pb-Pb collisions at LHC energies is dominated by dissociation limited to the early stage of the collision, whereas in the J/ψ case there is substantial experimental evidence of an additional regeneration component.

Investigations of Anisotropic Flow Using Multiparticle Azimuthal Correlations in pp, p-Pb, Xe-Xe, and Pb-Pb Collisions at the LHC

Measurements of anisotropic flow coefficients (v_{n}) and their cross-correlations using two- and multiparticle cumulant methods are reported in collisions of pp at sqrt[s]=13  TeV, p-Pb at a center-of-mass energy per nucleon pair sqrt[s_{NN}]=5.02  TeV, Xe-Xe at sqrt[s_{NN}]=5.44  TeV, and Pb-Pb at sqrt[s_{NN}]=5.02  TeV recorded with the ALICE detector. The multiplicity dependence of v_{n} is studied in a very wide range from 20 to 3000 particles produced in the midrapidity region |η|<0.8 for the transverse momentum range 0.2<p_{T}<3.0  GeV/c. An ordering of the coefficients v_{2}>v_{3}>v_{4} is found in pp and p-Pb collisions, similar to that seen in large collision systems, while a weak v_{2} multiplicity dependence is observed relative to nucleus-nucleus collisions in the same multiplicity range. Using a novel subevent method, v_{2} measured with four-particle cumulants is found to be compatible with that from six-particle cumulants in pp and p-Pb collisions. The magnitude of the correlation between v_{n}^{2} and v_{m}^{2}, evaluated with the symmetric cumulants SC(m,n) is observed to be positive at all multiplicities for v_{2} and v_{4}, while for v_{2} and v_{3} it is negative and changes sign for multiplicities below 100, which may indicate a different v_{n} fluctuation pattern in this multiplicity range. The observed long-range multiparticle azimuthal correlations in high multiplicity pp and p-Pb collisions can neither be described by pythia 8 nor by impact-parameter-Glasma, music, and ultrarelativistic quantum molecular dynamics model calculations, and hence, provide new insights into the understanding of collective effects in small collision systems.

Outcomes of Ductal Carcinoma In Situ According to Detection Modality: A Multicenter Study Comparing Recurrence Between Mammography and Breast US

The purpose of this study was to determine whether disease recurrence and intrinsic characteristics of ductal carcinoma in situ (DCIS) are associated with the imaging method of detection in asymptomatic women. This multicenter, retrospective study included 844 women treated for asymptomatic DCIS who had pre-operative mammography and breast ultrasonography (US) studies available. Of the 844 women, 25 (3.0%) developed recurrences. Patients in the US group had significantly lower 5- and 10-y recurrence-free survival (RFS) rates compared with patients in the mammography group (p = 0.011). US-detected DCIS showed significantly lower 5-and 10-y RFS rates compared with mammography-detected DCIS in patients <50 y or with mammographically dense breasts (p = 0.002 and 0.002, respectively). US as the detection modality (hazard ratio [HR]: 4.451; 95% confidence interval [CI]: 1.530, 12.950; p = 0.006) and HER2 positivity (HR: 4.036; 95% CI: 1.438; 11.330; p = 0.008) were significantly associated with recurrence. We concluded that US as the detection modality and HER2 positivity were significantly associated with recurrence in patients treated for asymptomatic DCIS.

First Observation of an Attractive Interaction between a Proton and a Cascade Baryon

This Letter presents the first experimental observation of the attractive strong interaction between a proton and a multistrange baryon (hyperon) Ξ^{-}. The result is extracted from two-particle correlations of combined p-Ξ^{-}⊕p[over ¯]-Ξ[over ¯]^{+} pairs measured in p-Pb collisions at sqrt[s_{NN}]=5.02  TeV at the LHC with ALICE. The measured correlation function is compared with the prediction obtained assuming only an attractive Coulomb interaction and a standard deviation in the range [3.6, 5.3] is found. Since the measured p-Ξ^{-}⊕p[over ¯]-Ξ[over ¯]^{+} correlation is significantly enhanced with respect to the Coulomb prediction, the presence of an additional, strong, attractive interaction is evident. The data are compatible with recent lattice calculations by the HAL-QCD Collaboration, with a standard deviation in the range [1.8, 3.7]. The lattice potential predicts a shallow repulsive Ξ^{-} interaction within pure neutron matter and this implies stiffer equations of state for neutron-rich matter including hyperons. Implications of the strong interaction for the modeling of neutron stars are discussed.

Follow-Up Strategies for Thyroid Nodules with Benign Cytology on Ultrasound-Guided Fine Needle Aspiration: Malignancy Rates of Management Guidelines Using Ultrasound Before and After the Era of the Bethesda System

Background: To evaluate differences in malignancy rates and consequent follow-up strategies for cytologically benign thyroid nodules before and after the introduction of the Bethesda system according to the risk stratification categories of four thyroid management guidelines. Methods: This retrospective study was approved by our institutional review board. In this study, 1716 thyroid nodules with initially benign cytologic diagnosis at ultrasound-guided fine needle aspiration (US-FNA) in 1695 patients were included: 1187 nodules from the pre-Bethesda period and 529 nodules from the post-Bethesda period. Based on US features, the thyroid nodules were categorized into the final assessment categories of the 2015 American Thyroid Association (ATA), the 2016 American Association of Clinical Endocrinologists, American College of Endocrinology, and Associazione Medici Endocrinologi, the American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TIRADS), and the European Thyroid Association guidelines for Ultrasound Malignancy Risk Stratification systems. Estimated malignancy rates before and after propensity score matching according to follow-up intervals were obtained. Results: Of the 1716 thyroid nodules benign on initial US-FNA, the malignancy rate was 3.2% (38 of 1187) in the pre-Bethesda period and 2.6% (14 of 529) in the post-Bethesda period (p = 0.641). The 2015 ATA high suspicion pattern and the ACR-TIRADS category 5 had high estimated malignancy rates of >5% in the post-Bethesda period (6.52 and 8.57, respectively). Positive findings that indicated US-FNA in the ACR-TIRADS had estimated malignancy rates of 5.26 and 5.67, respectively, while the remaining guidelines had estimated malignancy rates of <5% in both periods. Conclusions: Immediate diagnostic intervention after benign cytologic diagnosis may not be necessary regardless of the cytologic criteria applied, but it can be considered for the highly suspicious categories in the 2015 ATA or the ACR-TIRADS for benign cytologic diagnosis of the Bethesda system.

Diffusional kurtosis imaging for differentiation of additional suspicious lesions on preoperative breast MRI of patients with known breast cancer

PURPOSE

To investigate the potential of diffusional kurtosis imaging (DKI) and conventional diffusion-weighted imaging (DWI) in the evaluation of additional suspicious lesions at preoperative breast magnetic resonance imaging (MRI) in patients with breast cancer.

MATERIALS AND METHODS

Fifty-three additional suspicious lesions in 45 patients with breast cancer, which were detected on preoperative breast MRI, were examined with a 3-T MR system. DKI and DWI data were obtained using a spin-echo single-shot echo-planar imaging sequence with b-values of 0, 50, 600, 1000, and 3000 s/mm². Histogram parameters (mean, standard deviation, minimum, maximum, 10th, 25th, 50th, 75th, 90th percentiles, kurtosis, skewness and entropy) of ADC from DWI and diffusivity (D), kurtosis (K) from DKI were calculated after postprocessing. Parameters were compared between benign vs. ductal carcinoma in situ (DCIS) vs. invasive breast lesions and diagnostic performances were evaluated by receiver operating characteristic (ROC) analysis. Correlation between the mean values of D and K was analyzed according to lesion type.

RESULTS

Multiple histogram parameters of D (mean, 25th, 50th percentile, 75th percentile, and entropy) differed between benign and invasive breast lesions (all P < 0.005), but none differed between benign vs. DCIS. D-90th percentile differed between DCIS vs. invasive cancer (P = 0.040). K-10th percentile differed between benign vs. DCIS (P = 0.015). ADC-75th percentile differed between benign vs. invasive cancer and ADC-75th percentile, ADC-90th percentile differed between DCIS vs. invasive cancer, respectively (all P < 0.005). ROC curve analysis showed high specificity for discrimination between benign and invasive cancer. D-mean and K-mean showed strong correlation in benign (r_s = -0.813) and invasive lesions (r_s = -0.853), but no significant correlation in DCIS.

CONCLUSION

DKI may aid in the differentiation of additional suspicious lesions at preoperative breast MRI. Both ADC and DKI may have lower potential in differentiating DCIS from benign lesions.

Semimetallic Graphene for Infrared Sensing

Both photothermal and photovoltaic infrared (IR) detectors employ sensing materials that have an optical band gap. Different from these conventional materials, graphene has a conical band structure that imposes zero band gap. In this study, using the semimetallic multilayer graphene, IR detection at room temperature is realized. The relatively high Seebeck coefficient, ranging from 40 to 60 μV/K, compared to that of the metal, and the large optical absorption in the mid-IR region, in the wavelength range of 7-17 μm, enable graphene to detect IR without an absorber, which is essential for most IR detectors because the band gap of the sensing materials is much larger than the energy of IR and the incident IR can be absorbed directly by the sensing material. Thus, the incident IR can be absorbed directly by the sensing material in our device. The developed detector with a SiN membrane shows high responsivity and detectivity, which are 140 V/W and 5 × 10⁸ cm·Hz^1/2/W at 5 Hz, respectively. In addition, the IR sensor shows a response time of 600 μs. In the room-temperature operation of the IR sensor array without cooling, our sensors detect IR emitted from a human body and track the movement. The availability of large-area graphene in current technology opens new applications for metallic two-dimensional materials and a possibility for scale-up.

Comparison of breast tissue markers for tumor localization in breast cancer patients undergoing neoadjuvant chemotherapy

PURPOSE

The purpose of this study was to compare the visibility of breast tissue markers in cases of breast cancer on ultrasonography (US) after neoadjuvant chemotherapy (NAC) and to analyze whether the type of marker affected the choice of localization method after NAC.

METHODS

We included 153 tissue markers inserted within breast cancers that showed pathologically complete response (pCR) after NAC from January 2012 to April 2017. One of three types of markers (a surgical clip, Cormark, or UltraClip) was inserted. Medical records and imaging findings were retrospectively reviewed. We compared the visibility of the different types of tissue markers on US after NAC, and also compared the imaging modalities used in the preoperative localization. The chi-square test, Fisher exact test, and multiple logistic regression were used for analysis.

RESULTS

Of the 153 tissue markers, 56 were surgical clips, 61 Cormark, and 36 UltraClip. After NAC, residual lesions were not seen on US in 42 cases (27.5%). In multivariate analysis, the visibility of the surgical clips and Cormark markers was better than that of the UltraClip markers (odds ratio [OR], 5.467; 95% confidence interal [CI], 1.717 to 17.410; P=0.004 and OR, 3.045; 95% CI, 1.074 to 8.628; P=0.036, respectively). Among the 131 cases where localization targeting the marker was required, the proportion of US-guided localizations was significantly higher when a surgical clip was used than when an UltraClip marker was used (OR, 5.566; 95% CI, 1.610 to 19.246; P=0.007) in the multivariate analysis.

CONCLUSION

The type of breast tissue marker affected its visibility on US in cases with pCR after NAC, which in turn affected the localization methodology.

Role of elastography for downgrading BI-RADS category 4a breast lesions according to risk factors

BACKGROUND

Elastography has been introduced as an additional diagnostic tool to ultrasonography (US) which helps clinicians decide whether or not to perform biopsy on US-detected lesions.

PURPOSE

To evaluate the role of strain elastography in downgrading Breast Imaging Reporting and Data System (BI-RADS) category 4a breast lesions according to personal risk factors for breast cancer in asymptomatic women.

MATERIAL AND METHODS

Strain elastography features of a total of 255 asymptomatic category 4a lesions were classified as soft and not soft (intermediate and hard). Malignancy was confirmed by surgery or biopsy, and benignity was confirmed by surgery or biopsy with no change on US for at least six months. Malignancy rates of lesions with soft and not soft elastography were calculated according to the presence of risk factors.

RESULTS

Of 255 lesions, 25 (9.8%) were malignant and 230 (90.2%) were benign. Of 195 lesions in average-risk women, the malignancy rate of lesions with soft elastography was 1.5% (1/68), which was significantly lower than the 14.2% (18/127) of lesions with not soft elastography ( P = 0.004). Of 60 lesions in increased-risk women, the malignancy rate of lesions with soft elastography was 15.0% (3/20), which was not significantly different from the 7.5% (3/40) of lesions with not soft elastography ( P = 0.390).

CONCLUSION

In average-risk women, category 4a lesions with soft elastography could be followed up with US because of a low malignancy rate of 1.5%.

Azimuthal Anisotropy of Heavy-Flavor Decay Electrons in p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

Angular correlations between heavy-flavor decay electrons and charged particles at midrapidity (|η|<0.8) are measured in p-Pb collisions at sqrt[s_{NN}]=5.02  TeV. The analysis is carried out for the 0%-20% (high) and 60%-100% (low) multiplicity ranges. The jet contribution in the correlation distribution from high-multiplicity events is removed by subtracting the distribution from low-multiplicity events. An azimuthal modulation remains after removing the jet contribution, similar to previous observations in two-particle angular correlation measurements for light-flavor hadrons. A Fourier decomposition of the modulation results in a positive second-order coefficient (v_{2}) for heavy-flavor decay electrons in the transverse momentum interval 1.5<p_{T}<4  GeV/c in high-multiplicity events, with a significance larger than 5σ. The results are compared with those of charged particles at midrapidity and those of inclusive muons at forward rapidity. The v_{2} measurement of open heavy-flavor particles at midrapidity in small collision systems could provide crucial information to help interpret the anisotropies observed in such systems.

Abstract P4-14-04: Time course changes in serum FSH, estradiol, and menstruation restoration in premenopausal patients with breast cancer taking adjuvant tamoxifen after completing chemotherapy: A report from the ASTRRA study

BACKGROUND

Assessment of restoration of ovarian function after chemotherapy is critical with respect to the initiation of different types of endocrine treatment in young high risk breast cancer patients

METHODS

In total, 1289 women who remained premenopausal or resumed premenopausal status after chemotherapy were randomized to receive 5 years of tamoxifen or 5 years of tamoxifen plus 2 years of ovarian suppression. The patients who did not resume menstruation were followed up for 2 years with tamoxifen treatment after finishing chemotherapy. Prospectively collected consecutive post-chemotherapy hormone and menstruation data were available for 705 breast cancer patients who enrolled tamoxifen-only treatment group or did not resume menstruation during follow up. This analysis evaluated the proportion of patients with pre-menopausal FSH levels (&lt;30 mIU/ml), E2 levels (340 pg/ml), and menstruation at any time point during treatment with tamoxifen.

RESULTS

During 5 years of tamoxifen treatment after chemotherapy for premenopausal breast cancer patients, 62% of patients resumed menstruation. Menstruation returned in 92% of patients under 35 years old but only in 31% of patients over 45 years old. Ovarian function, defined by serum FSH and E2 levels, resumed in 94% and 65% of patients, respectively, over 5 years. Most patients achieved ovarian function restoration during the first 2 years after chemotherapy, with 47.1% resuming menstruation and 86.2% and 50.3% achieving pre-menopausal FSH and E2 levels, respectively, in the first 2 years. Clinical factors related to menstruation restoration were younger age (HR = 6.38, 95% CI 1.33-3.47), 6 month hormone profile after chemotherapy (FSH&lt;30: HR=1.67, 95% CI 1.28-2.17; E2 &gt;40: HR=2.96, 95% CI 2.25-3.89), and anthracycline without taxane chemotherapy (HR=1.63, 95% CI 1.25-2.13).

CONCLUSIONS

During 5 years of tamoxifen treatment after chemotherapy, half of patients experienced menstruation restoration, including most very young patients under 35 years. The majority of patients experienced menstruation restoration in the first 2 years of tamoxifen treatment.

Citation Format: Kim HJ, Noh WC, Nam SJ, Park B-w, Lee ES, Im SA, Jung YS, Yoon JH, Kang SS, Park KH, Lee S-J, Jung J, Lee MH, Cho SH, Kim SY, Kim H-A, Han S-H, Han W, Hur MH, Ahn SH. Time course changes in serum FSH, estradiol, and menstruation restoration in premenopausal patients with breast cancer taking adjuvant tamoxifen after completing chemotherapy: A report from the ASTRRA study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-14-04.

Correction to: Effect of training on ultrasonography (US) BI-RADS features for radiology residents: a multicenter study comparing performances after training

The original version of this article, published on 07 January 2019, unfortunately contained a mistake.