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IMPORTANCE: While nipple-sparing mastectomy (NSM) for breast cancer was only performed using the open method in the past, its frequency using endoscopic and robotic surgical instruments has been increasing rapidly. However, there are limited studies regarding postoperative complications and the benefits and drawbacks of minimal access NSM (M-NSM) compared with conventional NSM (C-NSM). OBJECTIVE: To examine the differences in postoperative complications between C-NSM and M-NSM. DESIGN, SETTING, PARTICIPANTS: This was a retrospective multicenter cohort study enrolling 1583 female patients aged 19 years and older with breast cancer who underwent NSM at 21 university hospitals in Korea between January 2018 and December 2020. Those with mastectomy without preserving the nipple-areolar complex (NAC), clinical or pathological malignancy in the NAC, inflammatory breast cancer, breast cancer infiltrating the chest wall or skin, metastatic breast cancer, or insufficient medical records were excluded. Data were analyzed from November 2021 to March 2024. EXPOSURES: M-NSM or C-NSM. MAIN OUTCOMES AND MEASURES: Clinicopathological factors and postoperative complications within 3 months of surgery were assessed. Statistical analyses, including logistic regression, were used to identify the factors associated with complications. RESULTS: There were 1356 individuals (mean [SD] age, 45.47 [8.56] years) undergoing C-NSM and 227 (mean [SD] age, 45.41 [7.99] years) undergoing M-NSM (35 endoscopy assisted and 192 robot assisted). There was no significant difference between the 2 groups regarding short- and long-term postoperative complications (<30 days: C-NSM, 465 of 1356 [34.29%] vs M-NSM, 73 of 227 [32.16%]; P = .53; <90 days: C-NSM, 525 of 1356 [38.72%] vs M-NSM, 73 of 227 [32.16%]; P = .06). Nipple-areolar complex necrosis was more common in the long term after C-NSM than M-NSM (C-NSM, 91 of 1356 [6.71%] vs M-NSM, 5 of 227 [2.20%]; P = .04). Wound infection occurred more frequently after M-NSM (C-NSM, 58 of 1356 [4.28%] vs M-NSM, 18 of 227 [7.93%]; P = .03). Postoperative seroma occurred more frequently after C-NSM (C-NSM, 193 of 1356 [14.23%] vs M-NSM, 21 of 227 [9.25%]; P = .04). Mild or severe breast ptosis was a significant risk factor for nipple or areolar necrosis (odds ratio [OR], 4.75; 95% CI, 1.66-13.60; P = .004 and OR, 8.78; 95% CI, 1.88-41.02; P = .006, respectively). Conversely, use of a midaxillary, anterior axillary, or axillary incision was associated with a lower risk of necrosis (OR for other incisions, 32.72; 95% CI, 2.11-508.36; P = .01). Necrosis occurred significantly less often in direct-to-implant breast reconstruction compared to other breast reconstructions (OR, 2.85; 95% CI, 1.11-7.34; P = .03). CONCLUSIONS AND RELEVANCE: The similar complication rates between C-NSM and M-NSM demonstrates that both methods were equally safe, allowing the choice to be guided by patient preferences and specific needs.

Knowledge gained through classification of microarray gene expression data is increasingly important as they are useful for phenotype classification of diseases. In this paper we propose a rule-based approach called 'Large Coverage Rule' for microarray data classification. The proposed approach is a parameter-free data-driven approach that constructs decision rule based on the expression values of a gene. A simple Rank-Based Scoring algorithm is proposed for selecting informative genes. The performance of the proposed approach is evaluated using ten publicly available gene expression data sets. From the simulation result, it is found that the proposed approach generates compact rules and produces comparatively good classification accuracy than the others. Gene ontology based biological semantics is also carried out to analyse the informative genes. Statistical analysis of test result shows that the generated rules are simple to interpret, highly comprehensible and classifies microarray data accurately.

Bone metastasis is an important factor for the treatment and prognosis of breast cancer patients. Whole-body bone scintigraphy (WBBS) can evaluate skeletal metastases, and 18F-FDG PET/CT seems to exhibit high specificity and accuracy in detecting bone metastases. However, there is a limitation of 18F-FDG PET in assessing sclerotic bone metastases because some lesions may be undetectable. Recent studies showed that 18F-fluoride PET/CT is more sensitive than WBBS in detecting bone metastases. This study aims to evaluate the usefulness of 18F-fluoride PET/CT by comparing it with WBBS and 18F-FDG PET/CT in breast cancer patients with osteosclerotic skeletal metastases.Nine breast cancer patients with suspected bone metastases (9 females; mean age ± SD, 55.6 ± 10.0 years) underwent 99mTc-MDP WBBS, 18F-FDG PET/CT and 18F-fluoride PET/CT. Lesion-based analysis of five regions of the skeletons (skull, vertebral column, thoracic cage, pelvic bones and long bones of extremities) and patient-based analysis were performed.18F-fluoride PET/CT, 18F-FDG PET/CT and WBBS detected 49, 20 and 25 true metastases, respectively. Sensitivity, specificity, positive predictive value and negative predictive value of 18F-fluoride PET/CT were 94.2 %, 46.3 %, 57.7 % and 91.2 %, respectively. Most true metastatic lesions on 18F-fluoride PET/CT had osteosclerotic change (45/49, 91.8 %), and only four lesions showed osteolytic change. Most lesions on 18F-FDG PET/CT also demonstrated osteosclerotic change (17/20, 85.0 %) with three osteolytic lesions. All true metastatic lesions detected on WBBS and 18F-FDG PET/CT were identified on 18F-fluoride PET/CT.18F-fluoride PET/CT is superior to WBBS or 18F-FDG PET/CT in detecting osteosclerotic metastatic lesions. 18F-fluoride PET/CT might be useful in evaluating osteosclerotic metastases in breast cancer patients.

Post-treatment survivorship has not been extensively studied, despite long-standing evidence that after breast cancer treatment, women need continuing support to deal with their physical and psychosocial concerns.

We present an efficient and robust algorithm for computing the perspective silhouette of the boundary of a general swept volume. We also construct the topology of connected components of the silhouette. At each instant t, a three-dimensional object moving along a trajectory touches the envelope surface of its swept volume along a characteristic curve Kt. The same instance of the moving object has a silhouette curve Lton its own boundary. The intersection Kt∩Ltcontributes to the silhouette of the general swept volume. We reformulate this problem as a system of two polynomial equations in three variables. The connected components of the resulting silhouette curves are constructed by detecting the instances where the two curves Ktand Ltintersect each other tangentially on the surface of the moving object. We also consider a general case where the eye position changes while moving along a predefined path. The problem is reformulated as a system of two polynomial equations in four variables, where the zero-set is a two-manifold. By analyzing the topology of the zero-set, we achieve an efficient algorithm for generating a continuous animation of perspective silhouettes of a general swept volume.

The control performance of a chemical process is determined by process structure as well as the performance of controllers. Therefore, the concept of “controllability” should be introduced in the early design stage to maximize the control performance. Structural information makes controllability evaluation possible by giving insights into the pathways of disturbances in the process. In this study, a simple controllability evaluation procedure is suggested to screen out design alternatives using relative order analysis and structural decomposition. The effectiveness of the proposed method was validated by comparing the results with the case of dynamical simulation.

This paper presents an efficient and robust geometric algorithm that classifies and detects all possible types of torus/sphere intersections, including all degenerate conic sections (circles) and singular intersections. Given a torus and a sphere, we treat one surface as an obstacle and the other surface as the envelope surface of a moving ball. In this case, theConfiguration space(C-space) obstacle is the same as the constant radius offset of the original obstacle, where the radius of the moving ball is taken as the offset distance. Based on the intersection between theC-spaceobstacle and the trajectory of the center of the moving ball, we detect all the intersection loops and singular contact point/circle of the original torus and sphere. Moreover, we generate exactly one starting point (for numerical curve tracing) on each connected component of the intersection curve. All required computations involve vector/distance computations and circle/circle intersections, which can be implemented efficiently and robustly. All degenerate conic sections (circles) can also be detected using a few additional simple geometric tests. The intersection curve itself (a quartic space curve, in general) is then approximated with a sequence of cubic curve segments.

Subcutaneous administration of desoxycorticosterone acetate (DOCA) to adrenalectomized rats at 50 and 100 μg/100 g of body weight/day reduced their spontaneous NaCl intake significantly. When hydrochlorothiazide (HCZ, 0.6 g/kg of food) was administered concurrently, the effect of DOCA was prevented and NaCl intake increased. The HCZ also increased the NaCl intake of untreated adrenalectomized rats. Hence, the presence of adrenal steroids is not required for this response. The results suggest that increased intake of NaCl solution by HCZ-treated, adrenalectomized rats may be related to increased urinary excretion of sodium. However, the mechanism by which increased sodium loss may mediate increased sodium intake requires elucidation.

BackgroundMRI and PET/CT are useful for assessing breast cancer patients after neoadjuvant chemotherapy (NAC).PurposeTo investigate the utility of MRI and PET/CT in the prediction of pathologic response to neoadjuvant chemotherapy using Miller-Payne grading system in patients with breast cancer.Material and MethodsFrom January 2008 to December 2010, 59 consecutive patients with pathologically proven breast cancer, who underwent neoadjuvant chemotherapy followed by surgery were retrospectively enrolled. The maximal diameter decrease rate and volume reduction rate by three-dimensional (3D) MRI and standardized uptake value (SUV) reduction rate by PET/CT were calculated and correlated with the Miller-Payne grading system using the Spearman rank correlation test. Patients with Miller-Payne grades 1 or 2 were classified into the non-responder group and patients with grades 3, 4, and 5 were in the responder group. To differentiate between responders and non-responders, receiver-operating characteristic (ROC) analysis was performed.ResultsThe volume reduction rate was 64.87 ± 46.95, diameter decrease rate was 48.09 ± 35.02, and SUV decrease rate was 62.10 ± 32.17. Among three parameters, the volume reduction rate was most correlated with histopathologic grades of regression (ρ = 0.755, P <0.0001) followed by diameter decrease rate (ρ = 0.660, P < 0.0001), and SUV decrease rate of primary breast mass (ρ = 0.561, P = 0.0002). The area under the ROC curve (Az) value was largest in the volume reduction rate (Az = 0.9), followed by SUV decrease rate (Az = 0.875), and diameter decrease rate (Az = 0.849). The best cut-offs for differentiating responders from non-responders in the ROC curve analysis were a 50% decrease in diameter, 68.9% decrease in volume, and 60.1% decrease in SUV after NAC.ConclusionVolumetric measurement using 3D MRI combined with conventional diameter measurement may be more accurate to evaluate pathologic response after NAC.