Efficient Haze Removal from a Single Image Using a DCP-Based Lightweight U-Net Neural Network Model.

In this paper, we propose a lightweight U-net architecture neural network model based on Dark Channel Prior (DCP) for efficient haze (fog) removal with a single input. The existing DCP requires high computational complexity in its operation. These computations are challenging to accelerate, and the problem is exacerbated when dealing with high-resolution images (videos), making it very difficult to apply to general-purpose applications. Our proposed model addresses this issue by employing a two-stage neural network structure, replacing the computationally complex operations of the conventional DCP with easily accelerated convolution operations to achieve high-quality fog removal. Furthermore, our proposed model is designed with an intuitive structure using a relatively small number of parameters (2M), utilizing resources efficiently. These features demonstrate the effectiveness and efficiency of the proposed model for fog removal. The experimental results show that the proposed neural network model achieves an average Peak Signal-to-Noise Ratio (PSNR) of 26.65 dB and a Structural Similarity Index Measure (SSIM) of 0.88, indicating an improvement in the average PSNR of 11.5 dB and in SSIM of 0.22 compared to the conventional DCP. This shows that the proposed neural network achieves comparable results to CNN-based neural networks that have achieved SOTA-class performance, despite its intuitive structure with a relatively small number of parameters.

Relationship between tamoxifen and cataracts: a nationwide cohort study of women in South Korea.

PURPOSE: Although prospective randomized clinical trials have reported that the use of prophylactic tamoxifen in patients at a high risk of breast cancer is associated with an increased risk of cataracts development, such findings are inconsistent. This study aimed to clarify the relationship between adjuvant tamoxifen use and cataracts risk using a nationwide longitudinal population-based registry. METHODS: This retrospective cohort study was conducted using the Korean National Health Insurance claims database over a 15-year period (January 2007-December 2021). Data from all female patients diagnosed with ductal carcinoma in situ (DCIS) between 2009 and 2015 were extracted. We evaluated the incidence of cataracts diagnosis and surgery after adjuvant tamoxifen administration in patients with DCIS. RESULTS: A total of 43,434 patients who met the inclusion criteria were diagnosed with DCIS between 2009 and 2015. Data from 2849 patients receiving tamoxifen and 1615 patients not receiving tamoxifen were analyzed before matching. After matching for comorbidities, type of breast surgery, and age, both groups consisted of 1597 patients. Both before and after matching, adjuvant tamoxifen was not a significant factor for an increased risk of cataracts diagnosis alone or with surgery. CONCLUSION: Our study showed that adjuvant tamoxifen was not a risk factor for increased cataracts diagnosis and surgery in patients with DCIS. This finding provides a basis for physicians to reduce their ocular toxicity concerns regarding the risk of patients developing cataracts by tamoxifen treatment.

Multi-Threaded Sound Propagation Algorithm to Improve Performance on Mobile Devices.

We propose a multi-threaded algorithm that can improve the performance of geometric acoustic (GA)-based sound propagation algorithms in mobile devices. In general, sound propagation algorithms require high computational cost because they perform based on ray tracing algorithms. For this reason, it is difficult to operate sound propagation algorithms in mobile environments. To solve this problem, we processed the early reflection and late reverberation steps in parallel and verified the performance in four scenes based on eight sound sources. The experimental results showed that the performance of the proposed method was on average 1.77 times better than that of the single-threaded method, demonstrating that our algorithm can improve the performance of mobile devices.

An Implementation of Inverse Cosine Hardware for Sound Rendering Applications.

Sound rendering is the process of determining the sound propagation path from an audio source to a listener and generating 3D sound based on it. This task demands complex calculations, including trigonometric functions. This paper presents hardware-based inverse cosine function calculations using the table method and linear approximation. This approach maintains a high accuracy while limiting hardware size for suitability in sound rendering applications. Consequently, our proposed hardware-based inverse cosine calculation method is a valuable tool for achieving high efficiency and accuracy in 3D sound rendering.

RT-induced dynamic changes in the lymphocyte-to-monocyte ratio in patients with breast cancer indicate poor prognosis.

PURPOSE: Radiation-induced anti-tumor responses occur in the immune system, particularly in peripheral blood mononuclear cells (PBMCs), which are overly sensitive to ionizing radiation. Irradiation of PBMCs is associated with inflammation. We assessed the association between radiotherapy (RT)-induced changes in peripheral blood cells, utilizing the lymphocyte-to-monocyte ratio (LMR), and survival outcome in breast cancer patients who underwent breast-conserving surgery followed by adjuvant RT. METHODS: LMR values were obtained from retrospective data, and serial sampling of blood before the first and last RT sessions was performed. The cut-off point was analyzed using the Youden index and receiver operating characteristic curve. Recurrence-free survival (RFS) and overall survival (OS) were the main outcomes. RESULTS: Patients with RT-induced low LMR had significantly shorter RFS (hazard ratio [HR] 2.730; 95% confidence interval [CI], 1.607-4.636, P = 0.0002) and OS (HR 2.890; 95% CI 1.410-5.924, P = 0.0038). The results were more robust in the subgroup of patients who received chemotherapy. Multivariate analysis showed that lymph node metastasis and RT-induced low LMR were associated with poor RFS (HR 1.763; 95% CI, 1.017-3.059, P = 0.044) and OS (HR 2.254; 95% CI, 1.060-4.796, P = 0.035). CONCLUSION: This study demonstrates that RT-induced low LMR is a valid prognostic marker for recurrence and survival in breast cancer patients undergoing RT.

The prognostic value of HER2 status and efficacy of anti-HER2 therapy in patients with HR-positive mucinous breast cancer: a nationwide study from the Korean Breast Cancer Society.

PURPOSE: The effect of human epidermal growth factor receptor 2 (HER2) status on mucinous carcinoma (MC) of the breast is unknown due to the rarity of HER2-positive cases. We evaluated the prognostic value of HER2 status and the efficacy of anti-HER2 therapy in patients with hormone receptor (HR)-positive MC. METHODS: From the data of 154,661 patients recorded in the Korean Breast Cancer Registry between January 1990 and August 2016, 3076 (2.0%) were diagnosed with MC. Overall survival (OS) according to HER2 status and anti-HER2 therapy was analyzed using Kaplan-Meier estimates. Multivariate analysis was performed using the Cox proportional hazards model to estimate the adjusted hazards ratio (HR) for clinicopathologic factors. RESULTS: A total of 2716 HR-positive MC patients were enrolled and followed up for a median 100.1 months. Of these, 2094 (77.1%) were HER2-negative and 228 (8.4%) were HER2-positive. HR-positive, HER2-positive MC patients had more advanced pathologic tumor stages (T3 or T4) (p = 0.001), more axillary lymph node involvement (p < 0.001), higher nuclear grade (p < 0.001), and more lymphovascular invasion (p = 0.012) than HER2-negative patients. Subgroup analysis of HR-positive, node-positive MC showed that HER2-positive MC was an independent prognostic factor for OS (HR = 2.657; 95% CI, 1.665-4.241; p < 0.001). HR-positive, node-positive, and HER2-negative MC had significantly longer OS than HER2-positive MBC (p = 0.017). The node-positive subgroup that received anti-HER2 therapy had increased OS, although not significantly (p = 0.224). CONCLUSION: Our nationwide database study revealed that HER2-positive status was associated with worse prognosis in HR-positive and node-positive MC. Anti-HER2 therapy might be beneficial in HR-positive, node-positive, and HER2-positive MC.

Axillary lymph node dissection is not obligatory in breast cancer patients with biopsy-proven axillary lymph node metastasis.

PURPOSE: The ACOSOG Z0011 trial demonstrated that axillary lymph node dissection (ALND) is unnecessary in select patients with cT1-2N0 tumors undergoing breast-conserving therapy with 1-2 positive sentinel lymph nodes (SLNs). However, patients with preoperatively confirmed ALN metastasis were not included and may be subjected to unnecessary ALND. The aim of this study is to identify patients who can be considered for ALND omission when the preoperative ALN biopsy results are positive. METHODS: Breast cancer patients who underwent preoperative ALN biopsy and primary surgery were retrospectively reviewed. Among patients with positive ALN biopsy results, clinicopathological and imaging characteristics were compared according to LN disease burden (1-2 positive LNs vs. ≥ 3 positive LNs). RESULTS: A total of 542 patients were included in the analysis. Among them, 225 (41.5%) patients had a preoperative positive ALN biopsy. More than 40% of the patients (n = 99, 44.0%) with a positive biopsy had only 1-2 positive ALNs. The association between nodal burden and imaging factors was strongest when ≥ 2 suspicious LNs were identified on PET/CT images (HR 8.795, 95% CI 4.756 to 13.262). More than one imaging modality showing ≥ 2 suspicious LNs was also strongly correlated with ≥ 3 positive ALNs (HR 5.148, 95% CI 2.881 to 9.200). CONCLUSIONS: Nearly half of patients with a preoperative biopsy-proven ALN metastasis had only 1-2 positive LNs on ALND. Patients meeting ACOSOG Z0011 criteria with only one suspicious LN on PET/CT or those presenting with few abnormal ALNs on only one imaging modality appear appropriate for SLNB and consideration of ALND omission.

Characteristics and prognosis of 17 special histologic subtypes of invasive breast cancers according to World Health Organization classification: comparative analysis to invasive carcinoma of no special type.

BACKGROUND: Breast cancer is a heterogeneous disease with various histopathologic subtypes. Except for invasive carcinoma of no special type (NST), other subtypes are rare with limited data. The purpose of this study was to analyze the characteristics and prognosis of special histopathologic subtypes of breast cancer compared to NST. METHODS: A total of 136,140 patients were analyzed using the Korean Breast Cancer Society Registry database between January 1996 and March 2019. The clinicopathologic features and survival outcomes of special type breast carcinoma were compared with those of NST. RESULTS: The prevalence of special subtypes other than NST was 13.7% (n = 18,633). Compared to NST, patients with lobular, medullary, metaplastic, and micropapillary carcinoma had larger tumors (p < 0.001). Patients with mucinous, tubular, medullary, metaplastic, and cribriform carcinoma presented with less node metastasis (p < 0.001), contrary to patients with micropapillary carcinoma. Patients with lobular, mucinous, tubular, papillary, and cribriform carcinoma presented as luminal A subtype much more often (p < 0.001). Micropapillary carcinoma included more luminal B subtype (p < 0.001). Typically, medullary and metaplastic carcinoma included more triple-negative subtypes (p < 0.001). In survival analysis, only medullary (Hazard Ratio (HzR) 0.542, 95% CI 0.345 to 0.852, p = 0.008) and metaplastic carcinoma (HzR 1.655, 95% CI 1.317 to 2.080, p < 0.001) showed significantly different overall survival from NST by multivariate analysis. CONCLUSION: Breast cancer had distinct clinicopathologic features according to histopathologic subtype. However, special types of breast cancer had similar survival outcomes compared to NST when adjusting for other prognostic factors, except for metaplastic carcinoma and medullary carcinoma.

Distinct Clinical Manifestations of Thyroid Cancer After Hematopoietic Stem Cell Transplantation.

BACKGROUND: The incidence of a secondary solid malignancy after hematopoietic cell transplantation (HCT) is increasing in long-term survivors. OBJECTIVE: The aim of this study was to compare the clinicopathological characteristics of HCT recipients with secondary thyroid cancer (STC), with those of non-HCT thyroid cancer patients. METHODS: We retrospectively investigated 5184 patients who received HCT between 1983 and 2016. Of these, 18 patients developed STC and underwent thyroidectomy due to differentiated thyroid cancer. We compared the clinicopathological characteristics of post-HCT thyroid cancer patients (post-HCT group) with those of a primary differentiated thyroid carcinoma cohort (cohort group) from Seoul St. Mary's Hospital. RESULTS: The mean ages at HCT and thyroidectomy after HCT were 22.0 and 31.8 years, respectively, and the median time interval between HCT and thyroidectomy was 5 years (range 1-16). Compared with the cohort group, the post-HCT group was younger at cancer onset and frequently had a palpable mass at initial diagnosis. The post-HCT group had more aggressive features, including larger tumor size, frequent extrathyroidal extension, lymphatic invasion, perineural invasion, and frequent lateral neck node metastasis and distant metastasis, relative to the cohort group; however, most patients (83.2%) in the post-HCT group were stage I or II. Additionally, BRAF V600E mutation was less frequent in the post-HCT group. CONCLUSIONS: We found that STC after HCT showed younger presentation and more aggressive clinical presentation. Therefore, a policy of regular screening, including neck ultrasound examination, may promote early detection and treatment in HCT recipients.

Chronologically changing patterns in the survival of korean patients with breast cancer and related clinical factors: a nationwide registry-based study.

PURPOSE: Advances in breast cancer treatment have contributed to marked improvements in patient outcomes over the past three decades. This study aims to chronologically evaluate the survival of patients with breast cancer and investigate the observed changes over time. METHODS: Statistics from the Korean National Cancer Registry, based on all 60,571 patients with invasive breast cancer during the 21 year period, were analyzed. We divided the study interval into four periods (P1: 1988-1992, P2: 1993-1997, P3: 1998-2002, P4: 2003-2008). RESULTS: The patients treated during P4 showed significantly better 5-year overall survival (OS) than did those treated during P1 (5Y OS; P1 = 79.0 vs. P4 = 92.2, p < 0.001). In the multivariate analyses, younger age, mastectomy, high stage, high tumor grade, lymphovascular invasion, and hormone receptor negativity were poor prognostic factors. The multivariate analysis demonstrated that diagnosis periods significantly and independently associated with OS in the overall group of patients. In our analysis of age-period-interaction models, the hazard ratio (HR) for death for patients who were under 35 years of age, compared to those who were older, tended to decrease over time (HR of age < 35 vs. 35 ~ 50; P1 = 0.739, p = 0.007; P2 = 0.744, p < 0.001; P3 = 0.886, p = 0.041; P4 = 0.983, p = 0.813). The survival rate of patients who underwent breast conserving surgery (BCS) has recently gotten better than that of mastectomy (HR of mastectomy vs. BCS; P1 = 0.957, p = 0.790; P2 = 0.542, p < 0.001; P3 = 0.543, p < 0.001; P4 = 0.425, p < 0.001). CONCLUSIONS: The clinical factors related to the changes in breast cancer survival have improved and increased patient OS over the past 20 years in Korea. In addition, we provided new insights into the effects of age and surgery methods on prognosis in each period.

Clinicopathologic characteristics and surgical outcomes of elderly patients with thyroid cancer.

OBJECTIVE: Age is one of the important prognostic factors in thyroid cancer, and old age is generally related to higher rate of post-operative morbidity and mortality. The study analyzed the characteristics of thyroid cancer in elderly patients compared with those in younger patients. METHODS: Patients who underwent surgery between 1992 and 2011 were enrolled. The patients were divided into those ≥70 years of age (older group) and <70 years of age (younger group). Data including clinicopathological features and post-operative complications was analyzed. Molecular markers including Galectin-3, Cyclooxygenase-2, bcl-2, Cyclin D1, Epidermal growth factor receptor and BRAF mutation were reviewed. Survival analyses including recurrence-free survival and overall survival were examined. RESULTS: Of 1867 patients, 98 were age-classified in older group and the remaining 1769 were in younger group. Older group displayed larger tumor size, and increased extrathyroidal extension, vascular invasion and neural invasion than younger group, and all were statistically significant. Molecular marker analyses revealed no significant differences between the groups. Post-operative complication rates were not significantly different between the older and younger groups in both univariate and multivariate analyses. Elderly patients showed poor recurrence-free survival and overall survival than younger patients in univariate analyses. However, age ≥70 years was not associated with poor recurrence-free survival after adjustment of confounding factors. CONCLUSION: Molecular features of elderly patients may be similar with younger patients. Even though aggravated clinicopathological features of thyroid carcinoma are more prevalent in elderly patients, thyroid surgery in elderly patients can be performed with favorable surgical and oncological outcomes.

Injectable alginate-based in situ self-healable transparent hydrogel as a vitreous substitute with a tamponading function.

Retinal detachment and other vision-threatening disorders often necessitate vitreous body removal and tamponade injection for retina stabilization. Current clinical tamponades such as silicone oil and expansile gases have drawbacks, including patient discomfort and the need for secondary surgery. We introduce a transparent alginate-phenylboronic acid/polyvinyl alcohol composite hydrogel (TALPPH) as a novel vitreous substitute with tamponading capabilities. In vitro physicochemical, rheological, and optical characterization of in situ self-healable TALPPH was performed, and long-term biocompatibility was assessed in a rabbit model of vitrectomy retinal detachment. In vivo evaluations confirmed TALPPH's ability to inhibit retinal detachment recurrence and preserve rabbit vision without adverse effects. TALPPH's close resemblance to the natural vitreous body suggests potential as a vitreous tamponade substitute for future ophthalmological applications.

Clinical implication of the BRAFV600E mutation in papillary thyroid carcinoma.

BACKGROUND: The BRAFV600E mutation is the most common genetic alteration in papillary thyroid carcinoma (PTC). In recent studies, the BRAFV600E mutation has been associated with poor clinicopathological characteristics, such as lymph node metastasis, extrathyroidal extension, and advanced stage. However, other studies have failed to establish an association between the BRAFV600E mutation and clinicopathological features. Therefore, we investigated the relationship between the BRAFV600E mutation and its clinicopathological factors at a single institution. METHODS: A total of 327 consecutive patients with PTC were enrolled in this study and underwent thyroid surgery at Yeouido St. Mary's Hospital between February 2010 and December 2011.BRAFV600E mutation analysis was performed using polymerase chain reaction (PCR)-based amplification of DNA extracted from paraffin-embedded tumour specimens. RESULTS: The BRAFV600E mutation was detected in the tumours of 241 (73.7%) patients. Lymph node metastasis, TNM stage, and multifocality were not significantly associated with the BRAFV600E mutation. However, larger tumour size, extrathyroidal extension, histologic type (classic type), and concurrent Hashimoto's thyroiditis were associated with the BRAFV600E mutation in the univariate analysis, although no clinicopathological features were associated with the BRAFV600E mutation in the multivariate analysis. CONCLUSION: There was no idependent prognostic factor associated with BRAFV600E mutation status in this study. The BRAFV600E mutation is unlikely to serve as a prognostic factor for PTC.

Association between tamoxifen and incidence of osteoporosis in Korean patients with ductal carcinoma in situ.

Introduction: The partial estrogen-agonist action of tamoxifen on bone receptors has beneficial effects on bone mineral density. However, in premenopausal women, the use of tamoxifen causes systemic estrogen depletion, which has detrimental effects on bone health. We aim to investigate the association between tamoxifen and osteoporosis in the real world using data from a longitudinal nationwide cohort of Korean patients. Methods: Data were collected from the National Health Insurance claims database in South Korea. Osteoporosis was defined by diagnostic codes accompanying prescription data for osteoporosis. The cumulative incidence was analyzed by Kaplan-Meier survival curves and the risk factors were analyzed using a multivariable Cox proportional hazard regression model. Results: Between 2009 and 2015, of the 4,654 women with ductal carcinoma in situ (DCIS) without prior osteoporosis, 2,970 were prescribed tamoxifen and 1,684 were not. A total of 356 DCIS survivors were later diagnosed with osteoporosis during a median follow-up period of 84 months. In the overall population, tamoxifen was associated with a low risk of osteoporosis, before and after propensity matching adjusted for age, operation type, and comorbidities (before matching, hazard ratio [HR]=0.69, 95% confidence interval [CI]=0.559-0.851, p<0.001; after matching, HR=0.664, 95% CI=0.513-0.858, p=0.002). In the subgroup analysis, findings were consistent in postmenopausal women but were not evident in the younger age group. Conclusion: In a nationwide cohort study, a low risk of osteoporosis was associated with the use of tamoxifen. The protective effect of tamoxifen was more profound in older women and was not related to the incidence of osteoporosis in younger women.

Prediction of Cardiac Toxicity by Measurement of Coronary Artery Calcium Scoring Method Using Chest Computed Tomography in Early Breast Cancer Patients Treated with Trastuzumab.

Background: In human epidermal growth factor receptor 2 (HER2)-positive early stage breast cancer, prediction of trastuzumab-related cardiac toxicity remains a challenge. The coronary calcium artery (CAC) reflects the total coronary plaque burden, which predicts the risk of atherosclerosis. We investigated the prediction of left ventricular ejection fraction (LVEF) decline in breast cancer according to CAC scores. Methods: A total of 347 patients were enrolled from Seoul St Mary's Hospital between January 2010 and December 2019. Chest computed tomography (CT) was performed at a single tertiary center. Patients who received trastuzumab for HER2-positive early breast cancer were included in this study. Results: Of the 347 patients, 312 and 35 had CAC scores of 0 and ≥1, respectively. The CAC ≥1 group was associated with older age, body mass index, and receipt of left breast irradiation. The CAC ≥1 group was significantly associated with LVEF decline (absolute value, ≤50%) (hazard ratio [HR] 12.038, 95% confidence interval [CI] 2.845-50.937, p = 0.001), LVEF decline (absolute value, ≤55%) (HR 4.439, 95% CI: 1.787-11.028, p = 0.001), and decline in LVEF of ≥10% points compared with baseline echography (HR 5.083, 95% CI: 1.658-15.582, p = 0.004). Even after adjusting for other clinical factors, CAC ≥1 remained a significant predictor of decreased LVEF. Conclusion: Our findings suggest that the CAC score is a significant predictor of cardiac toxicity following trastuzumab treatment in HER2-positive breast cancer. Therefore, CAC measurement could reduce cardiac toxicity by distinguishing patients at high risk for trastuzumab.

Marked Reduction in the Risk of Dementia in Patients with Breast Cancer: A Nationwide Population-Based Cohort Study.

PURPOSE: An inverse relationship between cancer and neurodegenerative disease, which presents the possibility of a reduced risk of dementia in cancer patients, has been suggested previously. However, a nationwide longitudinal population-based study of specific types of cancer with due consideration of treatment effects has not been conducted. Materials and Methods: This nationwide population-based cohort study used data obtained in a 12-year period (January 2007- December 2018) in the Korean National Health Insurance claims database. All female breast cancer patients (age ≥ 50 years) diagnosed between 2009 and 2010 were included after excluding those with physician visits for any cancer during a 2-year period (2007-2008). Patients with senile cataract constituted the control group. The main study outcome was the risk of developing dementia. RESULTS: From a total of 90,396 and 85,906 patients with breast cancer and cataract, respectively, patients without behavior codes were excluded. Data for 15,407 breast cancer patients and 7,020 controls were analyzed before matching. After matching for comorbidities and age, either group comprised 2,252 patients. The median follow-up time was 104.1±24.0 months after matching. After matching, breast cancer was a predictor of a lower risk of for dementia (hazard ratio, 0.091; 95% confidence interval, 0.075 to 0.111; p < 0.001). In breast cancer patients, receiving chemotherapy and endocrine therapy did not significantly affect the incidence of dementia. CONCLUSION: Breast cancer was associated with a remarkably decreased risk of dementia. The findings strongly suggest an inverse relationship between cancer and neurodegeneration, regardless of the adverse effects of cancer treatment on cognitive function.

An observational, prospective, open label, multicenter study to evaluate the safety and effectiveness of pegfilgrastim as secondary prophylaxis to decrease the incidence of febrile neutropenia in Korean female patients with breast cancer.

PURPOSE: Pegfilgrastim is a widely used long-acting granulocyte colony-stimulating factor (G-CSF) that prevents febrile neutropenia (FN) in patients with breast cancer receiving chemotherapy. This study aimed to evaluate the incidence of chemotherapy-related FN events and other adverse events (AEs) during chemotherapy in Korean patients with breast cancer treated with pegfilgrastim as secondary prophylactic support. MATERIALS AND METHODS: This was a multicenter, open-label, prospective, observational study. A total of 1255 patients were enrolled from 43 institutions. The incidence of FN was evaluated as the primary endpoint. The secondary endpoints included (1) incidence of bone pain, (2) proportion of patients with a relative dose intensity (RDI) of ≥85%, and (3) proportion of patients with AE. RESULTS: Pegfilgrastim administration reduced FN by 11.8-1.6%. The highest incidence of bone pain was observed at the time point of the 1st day after the administration and mild bone pain was the most common of all bone pain severity. The mean RDI was 98.5 ± 7.3%, and the proportion of the patients with and RDI≥85% was 96.9% (1169/1233). AEs were reported in 52.6% of the patients, and serious drug reactions occurred in only 0.7%. CONCLUSION: The use of pegfilgrastim as secondary prophylaxis was effective and safe for preventing FN in patients with breast cancer who were treated with chemotherapy.

Notch1 receptor as a marker of lymph node metastases in papillary thyroid cancer.

Notch functions as an oncogene or tumor suppressor according to the type of malignancy, and the BRAF(V600E) mutation is commonly observed in thyroid cancer. However, the role of Notch and BRAF(V600E) in papillary thyroid cancer (PTC) is unclear. This study sought to elucidate the clinicopathological characteristics in patients with PTC regarding the expression of Notch1/Notch3 receptors and BRAF(V600E) mutation. Clinicopathological characteristics were evaluated according to the Notch1/Notch3 receptors and BRAF(V600E) mutation in 187 patients with PTC who underwent definitive surgery. Expression of the Notch1 receptor was significantly associated with poor prognostic markers including large tumor size, nodal metastasis, capsular invasion, and extrathyroidal extension. However, there was no significant association between the clinicopathological characteristics and Notch3 receptor expression/BRAF(V600E) mutation. In multivariate analysis, Notch1 receptor expression showed a significant relationship with lymph node metastasis (P = 0.04). Notch1 receptor may be a predictor of lymph node metastasis and may be related to poor prognostic markers in patients with PTC. Further investigation of Notch1 receptor may further the understanding of the pathogenesis of nodal metastasis in PTC.

Clinical predictors of right upper paraesophageal lymph node metastasis from papillary thyroid carcinoma.

BACKGROUND: Central and lateral lymph node metastases are quite common in patients with papillary thyroid carcinoma, and the predictors for those metastases have been well studied. Right upper paraesophageal lymph node metastasis has rarely been studied. The aim of this study was to identify the clinicopathological characteristics that may be risk factors for right upper paraesophageal lymph node metastasis in patients with papillary thyroid carcinoma. METHODS: This was a prospective observational study of 243 patients with papillary thyroid carcinoma (PTC) who underwent total thyroidectomy and comprehensive central lymph node dissection with or without lateral lymph node dissection between April 2008 and January 2010. The clinicopathologic findings from these patients were investigated and the patterns of lymph node metastasis were analyzed in the patients who had right upper paraesophageal lymph node disease. RESULTS: Of the 243 patients undergoing lymph node dissection, 14 had right upper paraesophageal lymph node metastases. Two of these patients had right upper paraesophageal lymph node metastasis only, without central compartment metastasis. Univariate analysis of clinicopathologic findings showed that right upper paraesophageal lymph node metastasis had significant association with larger primary tumors, multifocal tumors, extrathyroid extension, and lymphatic invasion (p <0.05 for each factor). CONCLUSIONS: Although there were no independent predictors of right upper paraesophageal lymph node metastasis, it can be the only site of metastasis without other compartmental metastasis. Therefore, during surgery for patients with central or lateral lymph node metastases from PTC, it may be helpful to examine the right upper paraesophageal lymph nodes.

Avoiding unnecessary intraoperative sentinel lymph node frozen section biopsy of patients with early breast cancer.

Purpose: After the publication of the ACOSOG (American College of Surgeons Oncology Group) Z0011 trial, the rate of axillary lymph node dissection has reduced. Thus, the need for intraoperative frozen section biopsy of sentinel lymph nodes (SLNs) has become controversial. We identified patients for whom intraoperative SLN frozen section biopsy could be omitted and found that frozen section biopsy rate can be reduced. Methods: We reviewed the records of patients with tumors ≤5 cm in diameter who underwent breast-conserving surgery between January 2013 and December 2019 at Seoul St. Mary's Hospital. Clinicopathological and imaging characteristics were compared according to number of positive SLNs (0-2 SLNs positive vs. ≥3 SLNs positive). Results: A total of 1,983 patients were included in this study. Thirty-two patients (1.6%) had at least 3 positive SLNs. Patients with ≥3 positive SLNs had significantly larger tumors and were more frequently high-grade tumors (P < 0.001 and P = 0.002, respectively). Identification of suspicious lymph nodes on imaging studies was also associated with the presence of ≥3 positive SLNs (hazard ratio, 11.54; 95% confidence interval, 4.42-30.10). All patients with none or only 1 suspicious lymph node on any imaging modality (n = 647, 32.6%) had 0-2 positive SLNs. Also, among patients with clinical T1-stage tumors and at least 2 suspicious lymph nodes on only 1 imaging modality (n = 514, 25.9%), only 2 cases had ≥3 positive SLNs. Conclusion: We found that intraoperative SLN frozen biopsy could be omitted in patients using tumor size and axillary lymph node status on imaging modality.