Surveillance for Distant Metastasis in Breast Cancer Patients Who Underwent Contemporary Management: A Report from the Korean Breast Cancer Society Survivor Research Group.

BACKGROUND: Current guidelines recommend against the use of routine imaging tests to detect distant metastasis in asymptomatic breast cancer patients. However, recent advancements in effective therapeutics and diagnostic accuracy have raised the need to reassess the clinical efficacy of intensive metastasis surveillance. We report the results of a multicenter retrospective study to investigate the association between intensive imaging studies and survival outcomes. PATIENTS AND METHODS: We retrospectively reviewed the data of 4130 patients who underwent surgery from 11 hospitals in Korea between January 2010 and December 2011. Patients were divided into two groups on the basis of the intensity of metastasis imaging studies during their disease-free period. The types and intervals of the imaging studies were based on each physician's decisions. RESULTS: High-intensive screening showed a shorter distant metastasis-free survival [p < 0.001, hazard ratio (HR) 1.62; 95% confidence interval (CI) 1.29-2.04], especially for patients in whom bone or lung was the first site of metastasis. With a median follow-up period of 110.0 months, the 5-year breast cancer-specific survival (BCSS) rate was 96.5%. The high-intensity screening group showed significantly poorer BCSS compared with the low-intensity screening group (p < 0.001, HR 3.13; 95% CI 2.32-4.21). However, both multivariable analysis and propensity score matching analysis showed no significant association between the screening intensity and BCSS. CONCLUSIONS: Frequent imaging studies to detect distant metastasis were associated with earlier detection of distant metastasis, especially for lung and bone metastasis. However, intensive surveillance showed no apparent association with BCSS despite the use of currently available treatments.

Structural phase transition and resistive switching properties of CuxO films during post-thermal annealing.

We studied the phase change and resistive switching characteristics of copper oxide (CuxO) films through post-thermal annealing. This investigation aimed to assess the material's potential for a variety of electrical devices, exploring its versatility in electronic applications. The CuxO films deposited by RF magnetron sputtering were annealed at 300, 500, and 700 °C in ambient air for 4 min by rapid thermal annealing (RTA) method, and then it was confirmed that the structural phase change from Cu2O to CuO occurred with increasing annealing temperature. Resistive random-access memory (ReRAM) devices with Au/CuxO/p+-Si structures were fabricated, and the ReRAM properties appeared in CuO-based devices, while Cu2O ReRAM devices did not exhibit resistive switching behavior. The CuO ReRAM device annealed at 500 °C showed the best properties, with a on/off ratio of 8 × 102, good switching endurance of ∼100 cycles, data retention for 104s, and stable uniformity in the cumulative probability distribution. This characteristic change could be explained by the difference in the grain size and density of defects between the Cu2O and CuO films. These results demonstrate that superior and stable resistive switching properties of RF-sputtered CuxO films can be obtained by low-temperature RTA.

One-Step Passivation of Both Sulfur Vacancies and SiO2 Interface Traps of MoS2 Device.

Transition metal dichalcogenides (TMDs) benefit electrical devices with spin-orbit coupling and valley- and topology-related properties. However, TMD-based devices suffer from traps arising from defect sites inside the channel and the gate oxide interface. Deactivating them requires independent treatments, because the origins are dissimilar. This study introduces a single treatment to passivate defects in a multilayer MoS2 FET. By applying back-gate bias, protons from an H-TFSI droplet are injected into the MoS2, penetrating deeply enough to reach the SiO2 gate oxide. The characterizations employing low-temperature transport and deep-level transient spectroscopy (DLTS) studies reveal that the trap density of S vacancies in MoS2 drops to the lowest detection level. The temperature-dependent mobility plot on the SiO2 substrate resembles that of the h-BN substrate, implying that dangling bonds in SiO2 are passivated. The carrier mobility on the SiO2 substrate is enhanced by approximately 2200% after the injection.

Recurrence is Not Associated with Margin Status in Phyllodes Tumor.

BACKGROUND: Phyllodes tumor (PT) is a rare fibroepithelial neoplasm of the breast. The proper extent of resection is still under debate. This study aimed to investigate the optimal surgical margin to prevent recurrence after surgery for PT and to evaluate risk factors for local recurrence (LR). METHODS: Retrospective analysis of a prospective cohort database was performed. Patients who underwent curative surgery for PT at Seoul National University Bundang Hospital between July 2003 and February 2022 were reviewed. RESULTS: Of the 439 patients included, 285 were benign, 129 were borderline, and 25 were malignant. There was no statistically significant difference in 5-year disease-free survival (DFS) between margin-negative and margin-involved patients (87.3% vs. 85.1%, p = 0.081). When patients were classified into groups, according to margin status, as conventional (≥ 1 cm from tumor), close (< 1 cm from tumor), or involved, 5-year DFS rates were also similar (100% vs. 86.9% vs. 85.1%, p = 0.170). In subgroup analysis for different histologic grades, 5-year DFS was not affected by margin involvement. In univariate analysis, large tumor size (> 5 cm; hazard ratio [HR] 2.857, p = 0.028) and infiltrative tumor border (HR 3.096, p = 0.012) were independent risk factors for LR. Further multivariate analysis found both factors to be prognostic. CONCLUSIONS: Recurrence was not significantly influenced by margin status in all histological grades. In benign and borderline tumors, local excision without wide surgical margins could be sufficient, and watchful waiting could be an option for patients with positive margins after initial surgery.

Investigating charge traps in MoTe2field-effect transistors: SiO2insulator traps and MoTe2bulk traps.

Two-dimensional material-based field-effect transistors are promising for future use in electronic and optoelectronic applications. However, trap states existing in the transistors are known to hinder device performance. They capture/release carriers in the channel and lead to hysteresis in the transfer characteristics. In this work, we fabricated MoTe2field-effect transistors on two different gate dielectrics, SiO2and h-BN, and investigated temperature-dependent charge trapping behavior on the hysteresis in their transfer curves. We observed that devices with SiO2back-gate dielectric are affected by both SiO2insulator traps and MoTe2intrinsic bulk traps, with the latter becoming prominent at temperatures above 310 K. Conversely, devices with h-BN back-gate dielectric, which host a negligible number of insulator traps, primarily exhibit MoTe2bulk traps at high temperatures, enabling us to estimate the trap energy level at 389 meV below the conduction band edge. A similar energy level of 396 meV below the conduction band edge was observed from the emission current transient measurement. From a previous computational study, we expect these trap states to be the tellurium vacancy. Our results suggest that charge traps in MoTe2field-effect transistors can be reduced by careful selection of gate insulators, thus providing guidelines for device fabrication.

No axillary surgical treatment for lymph node-negative patients after ultra-sonography [NAUTILUS]: protocol of a prospective randomized clinical trial.

BACKGROUND: Following sentinel lymph node biopsy (SLNB), the axillary recurrence rate is very low although SLNB has a false-negative rate of 5-10%. In the ACOSOG Z0011 trial, non-sentinel positive-lymph nodes were found in more than 20% of the axillary dissection group; the SLNB only group did not have a higher axillary recurrence rate. These findings raised questions about the direct therapeutic effect of the SLNB. SLNB has post-surgical complications including lymphedema. Considering advances in imaging modalities and adjuvant therapies, the role of SLNB in early breast cancer needs to be re-evaluated. METHODS: The NAUTILUS trial is a prospective multicenter randomized controlled trial involving clinical stage T1-2 and N0 breast cancer patients receiving breast-conserving surgery. Axillary ultrasound is mandatory before surgery with predefined imaging criteria for inclusion. Ultrasound-guided core needle biopsy or needle aspiration of a suspicious node is allowed. Patients will be randomized (1:1) into the no-SLNB (test) and SLNB (control) groups. A total of 1734 patients are needed, considering a 5% non-inferiority margin, 5% significance level, 80% statistical power, and 10% dropout rate. All patients in the two groups will receive ipsilateral whole-breast radiation according to a predefined protocol. The primary endpoint of this trial is the 5-year invasive disease-free survival. The secondary endpoints are overall survival, distant metastasis-free survival, axillary recurrence rate, and quality of life of the patients. DISCUSSION: This trial will provide important evidence on the oncological safety of the omission of SLNB for early breast cancer patients undergoing breast-conserving surgery and receiving whole-breast radiation, especially when the axillary lymph node is not suspicious during preoperative axillary ultrasound. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04303715 . Registered on March 11, 2020.

The Potential Predictors in Chemotherapy Sensitivity.

Monitoring of patient and tumor during chemotherapy is important to determine whether the chemotherapy is effective to the patient. Variants affect drug enzyme activities and altered enzyme activities can be potential predictors for chemotherapeutic agents including cyclophosphamide and paclitaxel. Response to chemotherapy is primarily based on somatic mutations but germline variants may predict cancer cell sensitivity to chemotherapeutic agents. Furthermore, patient's genetic variation of immune system was reported to be associated with drug response and toxicity. Recently, the somaric and germilne genomic variation influences the pharmacokinetics of chemotherapy and these variation can be biomarkers for chemotherapy.

Genomic profiling of multiple breast cancer reveals inter-lesional heterogeneity.

BACKGROUND: Multiplicity in breast cancer is common. Studies on multiple breast cancers have revealed high concordance in biomarker status among individual lesions. However, genomic differences among multiple lesions are not well-established. We aimed to investigate the potential genomic heterogeneity of multiple breast cancer. METHODS: Twenty-one patients with radiologically and histologically evident multiple breast cancer with similar histology were included. Two lesions from each of the 21 patients were selected, and biomarker status was evaluated for each lesion. Capture-based targeted next-generation sequencing was performed using a cancer gene panel consisting of 170 genes. RESULTS: We identified discordance in intrinsic subtype in 2 (10%) of the 21 patients. Pathogenic mutations were detected in 13 of the 21 patients, of whom 11 shared oncogenic variants in the two lesions. The remaining two patients yielded different mutation results for TP53, ATM, and PIK3CA. Difference in copy number alteration was observed in 7 (33%) of the 21 patients including ERBB2 (n = 2), FGFR1 (n = 2), and FGFR2 (n = 1) genes. CONCLUSION: Despite similar histologic features of the individual lesions, inter-lesional genomic difference was identified in more than one-third of the patients. Inter-lesional genomic heterogeneity needs to be considered when performing a genomic test in multiple breast cancers.

Single-port laparoscopically harvested omental flap for immediate breast reconstruction.

PURPOSE: Immediate breast reconstruction using laparoscopically harvested omental flap is a safe and feasible technique, providing natural contour and softness to reconstructed breasts with reduced donor-site morbidity and deformity. We report our experience using single-port laparoscopically harvested omental flap (SLOF) for immediate breast reconstruction. METHODS: Between February 2015 and December 2018, 129 patients with malignant neoplasm of the breast underwent nipple-sparing mastectomy (NSM) or breast-conserving surgery (BCS) followed by immediate SLOF reconstruction at Seoul National University Bundang Hospital. We assessed their clinicopathological data, complications, and cosmetic and oncologic outcomes. Cosmetic outcomes were evaluated by three-panel assessment and the BCCT.core software program. RESULTS: One hundred and six (82.2%) underwent NSM and 23 (17.8%) underwent BCS. Mean operation time was 205 (range, 134-316) minutes. Most patients had early-stage disease; 15 (11.6%) received neoadjuvant chemotherapy. Two had malignant phyllodes tumors. Cosmetic outcomes were excellent or good in 96.9% by three-panel assessment and 99.2% by the BCCT.core program with a nearly invisible donor-site scar in the umbilicus. Harvest-associated complications occurred in five (3.9%) patients, including two umbilical wound infections, one intra-abdominal infection, one umbilical hernia, and one pedicle injury. Fat necrosis (13.2%) and epigastric bulging (21.7%) were common mastectomy- or reconstruction-associated complications, but most were mild and some resolved spontaneously. Over a median 38-month follow-up, there were three local, two regional, and three systemic recurrences. CONCLUSIONS: SLOF reconstruction is a feasible and safe option for immediate breast reconstruction after NSM or extensive BCS with minimal donor-site morbidity and great cosmetic outcomes.

External validation and modification of nomogram for predicting positive resection margins before breast conserving surgery.

PURPOSE: A positive resection margin after breast conserving surgery (BCS) is the most important risk factor for tumor recurrence. In 2012, Seoul National University Hospital (SNUH) breast surgery team developed a nomogram for predicting positive resection margins before BCS to provide individual surgical plans that could reduce local recurrence without increasing re-excision rates. The purpose of this study was to validate this nomogram using an external cohort and to test if addition of surgeon-related factor could improve its use as a predictive model. METHODS: A total of 419 patients with breast cancer who underwent BCS from January to December 2018 were retrospectively reviewed. Using the SNUH BCS nomogram, risk score for positive resection margins was calculated for 343 patients. The predictive accuracy of the nomogram was assessed, and multivariable logistic regression analyses were performed to evaluate the nomogram's predictive variables. RESULTS: The positive resection margin rate of the current external validation cohort was 13.5% (46 out of 343), compared to 14.6% (151 out of 1034) of the original study. The discrimination power of the SNUH BCS nomogram as measure by area under the receiver operating characteristics curve (AUC) was 0.656 [95% confidence interval (CI) 0.576-0.735]. This result is lower than expected value of 0.823 [95% CI 0.785-0.862], the AUC of the original study. Multivariable logistic regression analysis showed that, among the five nomogram variables, presence of tumor size discrepancy greater than 0.5 cm between MRI and ultrasonography (OR 2.445, p = 0.019) and presence of ductal carcinoma in situ on needle biopsy (OR 2.066, p = 0.048) were significantly associated with positive resection margins. Finally, the nomogram score was re-calculated by adding each surgeon's resection margin positive rate as odds ratio and the AUC was increased to 0.733. CONCLUSIONS: Validation of the SNUH BCS nomogram was not successful in the current study as much as its original publication. However, we could improve its predictive power by including surgeon-related factor. Before applying a published nomogram as a preoperative predictive model, we suggest each institution to validate the model and adjust it with surgeon-related factor. Addition of new factors to currently available nomograms holds promise for improving its applicability for breast cancer patients at the actual clinical level.

Identifying germline APOBEC3B deletion and immune phenotype in Korean patients with operable breast cancer.

BACKGROUND: Apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3B (APOBEC3B) is implicated in anti-viral immune response and cancer mutagenesis. Germline APOBEC3B deletion is associated with increased susceptibility to breast cancer. We aimed to evaluate the association between germline APOBEC3B deletion and clinical phenotypes of breast cancer in Korean patients with operable breast cancer. METHODS: Mononuclear blood cell DNA of 103 patients with operable breast cancer was collected at Seoul National University Bundang Hospital in 2009. The DNA was sequenced to analyze APOBEC3B deletion status. Further, tumor-infiltrating lymphocytes (TILs) and programmed cell death-ligand 1 (PD-L1) expression in tumor cells were measured using immunohistochemistry. RESULTS: Median age of breast cancer diagnosis was 46 (25-72). In APOBEC3B deletion analysis, 10 (9.7%), 36 (35.0%), and 57 (55.3%) patients were identified as two-copy deletion (A3Bdel/del), one-one copy deletion (A3Bdel/wt), and no deletion (A3Bwt/wt), respectively. For other cancer susceptibility gene alterations, 9 (8.7%) patients were identified as pathogenic variants: RAD51D (n = 1), GJB2 (n = 1), BRCA1 (n = 1), BRCA2 (n = 2), ATM (n = 1), USH2A (n = 1), RET (n = 1), BARD1 (n = 1). We observed no significant association between germline APOBEC3B deletion with any clinicopathologic features of breast cancer, such as age, family history of cancer, and bilateral breast cancer. Further, according to follow-up observations, APOBEC3B deletion was not predictive of disease-free survival. In ER+ subtype, a trend toward better survival was observed in patients with A3Bdel/del genotype as compared to patients with A3Bdel/wt and A3Bwt/wt genotype (log-rank, P = 0.25). In patients with sufficient tumor samples for the assessment of TIL (n = 63) and PD-L1 (n = 71), the A3Bdel/del genotype was significantly associated with high TILs (> 10%) than other tumor genotypes (6/7 patients in A3Bdel/del vs. 13/24 in A3Bdel/wt vs. 15/32 in A3Bwt/wt: Fisher's exact test, P = 0.029). However, PD-L1 expression was not associated with APOBEC3B deletion status (1/7 patients > 1% PD-L1 in A3Bdel/del vs. 4/26 in A3Bdel/wt vs. 8/38 in A3Bwt/wt: P = 0.901). CONCLUSION: We identified germline APOBEC3B deletion in 9.7% of Korean patients with operable breast cancer. The relationship between A3Bdel/del genotype and high TILs suggests that patients carrying this genotype could be potential candidates for immunotherapy.

Analysis of ZnS and MgF2 layered nanostructures grown by glancing angle deposition for optical design.

This study investigated the multilayer growth and properties of ZnS and MgF2 using glancing angle deposition. We used deposition angles of 85°-89° for ZnS and 70°-88° for MgF2 to obtain the structural properties. The film properties primarily followed Tait's rule with a deposition angle of less than 87° in the vapor flux. However, film growth with a vapor flux angle of 88°-89° followed the tangent rule. Mathematical and cross-sectional scanning electron microscopy examinations found a transition point for the growth mechanisms at 87°, which comes from an extreme angle property for glancing angle deposition. We also performed mathematical derivations for the well-known empirical formula of the tangent rule and its generalized version. To stabilize the interface structure and surface roughness of multilayer structures, film growth at slightly tilted angles is recommended. Based on these results, an optical structure was designed, fabricated, and analyzed for a 550 nm wavelength pass filter on a glass substrate.

The enhancement mechanism of photo-response depending on oxygen pressure for Ga2O3 photo detectors.

We have optimized the responsivity and response speed of a ß-Ga2O3-based photodetector. The ß-Ga2O3 thin films were deposited on a glass substrate under various oxygen partial pressures from 0 to 50 mTorr using pulsed laser deposition. Time-response measurements show that the as-grown ß-Ga2O3 at an oxygen partial pressure of 50 mTorr has the fastest response speed and decay times of 33 and 100 ms, which are better than those prepared at lower oxygen pressures. This sample also showed a high photoresponsivity of 5 A W-1 and detectivity of 1012 cmHz1/2/W. The high performance of the ß-Ga2O3 detector grown at the oxygen partial pressure of 50 mTorr might be due to the reduction of oxygen vacancies caused by the increase in oxygen content during deposition. The results reveal the importance of the oxygen processing gas in promoting photodetector performance.

Photoelectric Characteristics of a Large-Area n-MoS2/p-Si Heterojunction Structure Formed through Sulfurization Process.

Two-dimensional (2D) materials, such as molybdenum disulfide (MoS2) of the transition metal dichalcogenides family, are widely investigated because of their outstanding electrical and optical properties. However, not much of the 2D materials research completed to date has covered large-area structures comprised of high-quality heterojunction diodes. We fabricated a large-area n-MoS2/p-Si heterojunction structure by sulfurization of MoOx film, which is thermally evaporated on p-type silicon substrate. The n-MoS2/p-Si structure possessed excellent diode characteristics such as ideality factor of 1.53 and rectification ratio in excess of 104. Photoresponsivity and detectivity of the diode showed up to 475 mA/W and 6.5 × 1011 Jones, respectively, in wavelength ranges from visible to near-infrared. The device appeared also the maximum external quantum efficiency of 72%. The rise and decay times of optical transient response were measured about 19.78 ms and 0.99 ms, respectively. These results suggest that the sulfurization process for large-area 2D heterojunction with MoS2 can be applicable to next-generation electronic and optoelectronic devices.

Polarization-Sensitive and Wide Incidence Angle-Insensitive Fabry-Perot Optical Cavity Bounded by Two Metal Grating Layers.

Infrared (IR) polarimetric imaging has attracted attention as a promising technology in many fields. Generally, superpixels consisting of linear polarizer elements at different angles plus IR imaging array are used to obtain the polarized target signature by using the detected polarization-sensitive intensities. However, the spatial arrangement of superpixels across the imaging array may lead to an incorrect polarimetric signature of a target, due to the range of angles from which the incident radiation can be collected by the detector. In this article, we demonstrate the effect of the incident angle on the polarization performance of an alternative structure where a dielectric layer is inserted between the nanoimprinted subwavelength grating layers. The well-designed spacer creates the Fabry-Perot cavity resonance, and thereby, the intensity of transverse-magnetic I-polarized light transmitted through two metal grating layers is increased as compared with a single-layer metal grating, whereas transverse-electric (TE)-transmitted light intensity is decreased. TM-transmittance and polarization extinction ratio (PER) of normally incident light of wavelength 4.5 µm are obtained with 0.49 and 132, respectively, as the performance of the stacked subwavelength gratings. The relative change of the PERs for nanoimprint-lithographically fabricated double-layer grating samples that are less than 6% at an angle of incidence up to 25°, as compared to the normal incidence. Our work can pave the way for practical and efficient polarization-sensitive elements, which are useful for many IR polarimetric imaging applications.

Long-Term Chemical Aging of Hybrid Halide Perovskites.

Because the power conversion efficiency (PCE) of hybrid halide perovskite solar cells (PSCs) could exceed 24%, extensive research has been focused on improving their long-term stability for commercialization in the near future. In a previous study, we reported that the addition of a number of ionized iodide (triiodide: I3-) ions during perovskite film formation significantly improved the efficiency of PSCs by reducing deep-level defects in the perovskite layer. Understanding the relationship between the concentration of these defects and the long-term chemical aging of PSCs is important not only for obtaining fundamental insight into the perovskite materials but also for studying the long-term chemical stability of PSCs. Herein we aim to identify the origin of the natural decay in PCE during long-term chemical aging of PSCs in the dark based on formamidinium lead triiodide by comparing the performance of control and low-defect (LD) devices. After aging for 200 days, the change in the PCE of the LD devices (1.3%) was found to be half that of the control devices (2.6%). We investigated this difference using grazing incidence wide-angle X-ray scattering, deep-level transient spectroscopy, scanning photoelectron microscopy, and high-resolution photoemission spectroscopy. The addition of I3- was found to reduce the amounts of hydroxide and Ox in the halide perovskites (HPs), affecting the migration of defects and the structural transformation of the HPs.

Risk stratification of triple-negative breast cancer with core gene signatures associated with chemoresponse and prognosis.

PURPOSE: Neoadjuvant chemotherapy studies have consistently reported a strong correlation between pathologic response and long-term outcome in triple-negative breast cancer (TNBC). We aimed to define minimal gene signatures for predicting chemoresponse by a three-step approach and to further develop a risk-stratification method of TNBC. METHODS: The first step involved the detection of genes associated with resistance to docetaxel in eight TNBC cell lines, leading to identification of thousands of candidate genes. Through subsequent second and third step analyses with gene set enrichment analysis and survival analysis using public expression profiles, the candidate gene list was reduced to prognostic core gene signatures comprising ten or four genes. RESULTS: The prognostic core gene signatures include three up-regulated (CEBPD, MMP20, and WLS) and seven down-regulated genes (ASF1A, ASPSCR1, CHAF1B, DNMT1, GINS2, GOLGA2P5, and SKA1). We further develop a simple risk-stratification method based on expression profiles of the core genes. Relative expression values of the up-regulated and down-regulated core genes were averaged into two scores, Up and Down scores, respectively; then samples were stratified by a diagonal line in a xy plot of the Up and Down scores. Based on this method, the patients were successfully divided into subgroups with distinct chemoresponse and prognosis. The prognostic power of the method was validated in three independent public datasets containing 230, 141, and 117 TNBC patients with chemotherapy. In multivariable Cox regression analysis, the core gene signatures were significantly associated with prognosis independent of tumor stage and age at diagnosis. In meta-analysis, we found that five core genes (CEBPD, WLS, CHAF1B, GINS2, and SKA1) play opposing roles, either tumor promoter or suppressor, in TNBC and non-TNBC tumors respectively, depending on estrogen receptor status. CONCLUSIONS: The results may provide a promising prognostic tool for predicting chemotherapy responders among TNBC patients prior to initiation of chemotherapeutic treatment.

Is the high proportion of young age at breast cancer onset a unique feature of Asian breast cancer?

PURPOSE: Women with breast cancer in Asian and Western countries are similar in many respects, but there are also differences, such as in the age at onset and the proportion of breast cancer occurring at younger ages. There is controversy as to whether these differences are due to inter-racial genetic differences or to environmental or other factors. METHODS: Using the Korean Breast Cancer Society's large breast cancer registry, we investigated the causes of Koreans' unique breast cancer characteristics by examining the changes in the incidence and proportion of young-onset breast cancer (YBC) in Korea over time. We analyzed data from 108,894 patients to compare characteristics between patients with YBC and non-YBC. For a subtype analysis, we analyzed data from 85,691 patients from 2000. RESULTS: Among the 108,894 patients, 17,877 (15.5%) had YBC. The tumors associated with YBC showed aggressive clinicopathologic features. The incidence of breast cancer in Korea has increased over time, and while both YBC and non-YBC increased each year, the increase in non-YBC was more pronounced; thus, the proportion of YBC has decreased over time. By 2020, it appears that the ratio of YBC in Korea will be similar to that in Western countries. The increase in YBC was mainly due to an increase in the luminal A subtype. The incidence of other YBC subtypes did not change over time. CONCLUSIONS: Our data suggest that the current high proportion of YBC is probably not a unique feature of breast cancer in Asia but rather a transient phenomenon. Additionally, our results indirectly suggest that there were different causes for breast cancer in different age groups, suggesting the importance of using different approaches for different age groups to establish policies for preventing breast cancer.

Benign Breast Papilloma without Atypia: Outcomes of Surgical Excision versus US-guided Directional Vacuum-assisted Removal or US Follow-up.

Background Recent studies suggest that US-guided directional vacuum-assisted removal (DVAR) is a satisfactory alternative to surgery for benign papilloma of the breast and recommend discretionary diagnostic US follow-up without intervention. Purpose To compare the outcomes of benign papilloma without atypia diagnosed with core needle biopsy (CNB) in patients who underwent US-guided DVAR, US follow-up without intervention, or surgery. Materials and Methods This retrospective review included consecutive patients with benign papilloma without atypia diagnosed with US-guided CNB between January 2005 and September 2015. Five hundred female patients who underwent surgical excision (n = 206), US-guided DVAR (n = 233), or more than 2 years of US follow-up without intervention (n = 61) were included. The clinical and radiologic findings and cancer upgrade rate were compared among the three groups. Propensity score matching was performed for comparison of the upgrade rate in the surgery and US-guided DVAR groups. Results The mean patient age (±standard deviation) was 46.4 years ± 9.6. The upgrade rate to malignancy was 1.8% (nine of 500 patients; 95% confidence interval [CI]: 0.9%, 3.4%) in the total study population, 1.9% (four of 206 patients; 95% CI: 0.8%, 4.9%) after surgery, 2.1% (five of 233 patients; 95% CI: 0.9%, 4.9%) after US-guided DVAR, and 0% (0 of 61 patients; 95% CI: 0.0%, 5.9%) after US follow-up without intervention (P = .80); after propensity-score matching, the upgrade rate was 1.9% in the surgery group (three of 151 patients; 95% CI: 0.6%, 5.6%) and 3.3% in the US-guided DVAR group (five of 151 patients; 95% CI: 1.4%, 7.5%; P = .48). The recurrence rate after US-guided DVAR was 3.6% (six of 166 patients) during 24-65 months of follow-up; all recurrences were confirmed as benign at subsequent surgery. Fifty-nine of the 61 lesions in the group with US follow-up without intervention (97%) remained stable in size with no growth during a mean follow-up of 43.3 months (range, 25-130 months). Conclusion Low rates of upgrade, recurrence, and growth after US-guided directional vacuum-assisted removal and US follow-up without intervention suggest that benign papilloma without atypia can be managed more conservatively rather than undergoing surgical excision. © RSNA, 2019 Online supplemental material is available for this article.

Comparison of the Diagnostic Performance of Synthetic Versus Acquired High b-Value (1500 s/mm2 ) Diffusion-Weighted MRI in Women With Breast Cancers.

BACKGROUND: Acquired high b-value (>1000 s/mm2 ) diffusion-weighted imaging (DWI) has its strength in lesion detection. However, it is not easily used, due to a lower signal-to-noise ratio, eddy current distortions, and prolonged acquisition times. Synthetic DWI does not have these disadvantages because it is based on indirect acquisition, calculated in a voxel-wise manner. PURPOSE: To compare the diagnostic performance of synthetic and acquired high b-value (1500 s/mm2 ) DWI in women with breast cancer. STUDY TYPE: Retrospective. POPULATION: A total of 108 patients (median age 49 years [range 32-77]) with 133 breast cancers. FIELD STRENGTH/SEQUENCE: 3T, echo-planar imaging. ASSESSMENT: Three radiologists independently reviewed image sets of both synthetic (S-b1500) and acquired (A-b1500) high b-value DWI. Malignancy confidence of the lesion was scored using a 6-point Likert-type scale. STATISTICAL TEST: Jack-knife alternative free-response receiver-operating characteristic 1 (JAFROC1) analysis was used. Sensitivity and positive predictive value (PPV) were compared using generalized estimating equations. An independent t-test was used to compare the confidence. An intraclass correlation coefficient was calculated to compare interobserver agreement. RESULTS: The JAFROC1 figures of merit values were 0.816 and 0.808 in S-b1500 and A-b1500, respectively, with no statistically significant difference (P = 0.637). Sensitivity was higher in synthetic than in A-b1500 for readers 2 (P = 0.015) and 3 (P = 0.037). Although sensitivity was higher in S-b1500 than in A-b1500 for reader 1, the difference was not significant (P = 0.487). The PPV of S-b1500 was not significantly different from that of A-b1500 (P = 0.397). The malignancy confidence of true-positive tumors was higher in S-b1500 than in A-b1500 (P = 0.013). Interobserver agreement was good for both sequences. DATA CONCLUSIONS: The synthetic high b-value DWI may improve the diagnostic sensitivity for breast cancer detection without affecting PPV compared with acquired high b-value DWI. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:857-863.