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1.
Eur Radiol ; 34(4): 2576-2589, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37782338

RESUMO

OBJECTIVES: To develop a radiomics model in contrast-enhanced cone-beam breast CT (CE-CBBCT) for preoperative prediction of axillary lymph node (ALN) status and metastatic burden of breast cancer. METHODS: Two hundred and seventy-four patients who underwent CE-CBBCT examination with two scanners between 2012 and 2021 from two institutions were enrolled. The primary tumor was annotated in each patient image, from which 1781 radiomics features were extracted with PyRadiomics. After feature selection, support vector machine models were developed to predict ALN status and metastatic burden. To avoid overfitting on a specific patient subset, 100 randomly stratified splits were made to assign the patients to either training/fine-tuning or test set. Area under the receiver operating characteristic curve (AUC) of these radiomics models was compared to those obtained when training the models only with clinical features and combined clinical-radiomics descriptors. Ground truth was established by histopathology. RESULTS: One hundred and eighteen patients had ALN metastasis (N + (≥ 1)). Of these, 74 had low burden (N + (1~2)) and 44 high burden (N + (≥ 3)). The remaining 156 patients had none (N0). AUC values across the 100 test repeats in predicting ALN status (N0/N + (≥ 1)) were 0.75 ± 0.05 (0.67~0.93, radiomics model), 0.68 ± 0.07 (0.53~0.85, clinical model), and 0.74 ± 0.05 (0.67~0.88, combined model). For metastatic burden prediction (N + (1~2)/N + (≥ 3)), AUC values were 0.65 ± 0.10 (0.50~0.88, radiomics model), 0.55 ± 0.10 (0.40~0.80, clinical model), and 0.64 ± 0.09 (0.50~0.90, combined model), with all the ranges spanning 0.5. In both cases, the radiomics model was significantly better than the clinical model (both p < 0.01) and comparable with the combined model (p = 0.56 and 0.64). CONCLUSIONS: Radiomics features of primary tumors could have potential in predicting ALN metastasis in CE-CBBCT imaging. CLINICAL RELEVANCE STATEMENT: The findings support potential clinical use of radiomics for predicting axillary lymph node metastasis in breast cancer patients and addressing the limited axilla coverage of cone-beam breast CT. KEY POINTS: • Contrast-enhanced cone-beam breast CT-based radiomics could have potential to predict N0 vs. N + (≥ 1) and, to a limited extent, N + (1~2) vs. N + (≥ 3) from primary tumor, and this could help address the limited axilla coverage, pending future verifications on larger cohorts. • The average AUC of radiomics and combined models was significantly higher than that of clinical models but showed no significant difference between themselves. • Radiomics features descriptive of tumor texture were found informative on axillary lymph node status, highlighting a higher heterogeneity for tumor with positive axillary lymph node.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Metástase Linfática/patologia , Axila/patologia , Radiômica , Estudos Retrospectivos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Tomografia Computadorizada de Feixe Cônico
2.
Acta Radiol ; 64(3): 962-970, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35815702

RESUMO

BACKGROUND: Calcifications are important abnormal findings in breast imaging and help in the diagnosis of breast cancer. PURPOSE: To compare breast cone-beam computed tomography (CBCT) with digital mammography (DM) in terms of the ability to identify malignant calcifications. MATERIAL AND METHODS: In total, 115 paired examinations were performed utilizing breast CBCT and DM; 86 pathology-proven malignant lesions with calcifications detected on DM and 29 randomly selected breasts without calcifications were reviewed by three radiologists. The ability to detect calcifications was assessed on CBCT images. The characterization agreement of two imaging modalities was evaluated by the kappa coefficient. For breast CBCT images, the parameters for the display of calcifications were recorded. The Kruskal-Wallis test was used to compare the preferred slice thickness chosen by each of the three radiologists. The degree of calcification clarity was compared between two modalities using the Mann-Whitney U-test. RESULTS: The combined sensitivity and specificity of three radiologists in 85 DM-detected calcifications detection on breast CBCT images were 98.43% (251/255) and 98.85% (86/87), respectively. CBCT images showed substantial agreement with mammograms in terms of the characterization of calcifications morphology (k = 0.703; P < 0.05) and distribution (k = 0.629; P < 0.05). CBCT images with a slice thickness of 0.273 mm and three-dimensional maximum-intensity projection (3D-MIP) were more beneficial for calcifications identification. No statistically significant difference was found between standard DM views and CBCT images for three radiologists on calcification display clarity. CONCLUSION: CBCT images were comparable to mammograms in calcification identification and may be sufficient for malignant calcifications detection and characterization.


Assuntos
Neoplasias da Mama , Calcinose , Humanos , Feminino , Mamografia/métodos , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Calcinose/diagnóstico por imagem , Calcinose/patologia , Tomografia Computadorizada de Feixe Cônico/métodos
3.
Radiol Med ; 128(12): 1472-1482, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37857980

RESUMO

PURPOSE: Cone-beam breast CT (CBBCT) has an inherent limitation that the axilla cannot be imaged in its entirety. We aimed to develop and validate a nomogram based on clinical factors and contrast-enhanced (CE) CBBCT radiomics features to predict axillary lymph node (ALN) metastasis and complement limited axilla coverage. MATERIAL AND METHODS: This retrospective study included 312 patients with breast cancer from two hospitals who underwent CE-CBBCT examination in a clinical trial (NCT01792999) during 2012-2020. Patients from TCIH comprised training set (n = 176) and validation set (n = 43), and patients from SYSUCC comprised external test set (n = 93). 3D ROIs were delineated manually and radiomics features were extracted by 3D Slicer software. RadScore was calculated and radiomics model was constructed after feature selection. Clinical model was built on independent predictors. Nomogram was developed with independent clinical predictors and RadScore. Diagnostic performance was compared among three models by ROC curve, and decision curve analysis (DCA) was used to evaluate the clinical utility of nomogram. RESULTS: A total of 139 patients were ALN positive and 173 patients were negative. Twelve radiomics features remained after feature selection. Location and focality were selected as independent predictors for ALN status. The AUC of nomogram in external test set was higher than that of clinical model (0.80 vs. 0.66, p = 0.012). DCA demonstrated that the nomogram had higher overall net benefit than that of clinical model. CONCLUSION: The nomogram combined CE-CBBCT-based radiomics features and clinical factors could have potential in distinguishing ALN positive from negative and addressing the limitation of axilla coverage in CBBCT.


Assuntos
Linfonodos , Nomogramas , Humanos , Estudos Retrospectivos , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Axila/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Tomografia Computadorizada por Raios X/métodos
4.
Eur Radiol ; 32(8): 5773-5782, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35320411

RESUMO

OBJECTIVES: To compare the background parenchymal enhancement (BPE) levels on contrast-enhanced cone-beam breast CT (CE-CBBCT) and MRI, evaluate inter-reader reliability, and analyze the relationship between clinical factors and BPE level on CE-CBBCT. METHODS: In this retrospective study, patients who underwent both CE-CBBCT and MRI were analyzed. BPE levels on CE-CBBCT and MRI were assessed by five specialists independently in random fashion, with a wash-out period of 4 weeks. Weighted kappa was used to analyze the agreement between CE-CBBCT and MRI, and intraclass correlation coefficient (ICC) was used to evaluate the inter-reader reliability for each modality. The association between BPE level on CE-CBBCT and clinical factors was evaluated by univariate and multivariate logistic regression. RESULTS: A total of 221 patients from January 2017 to April 2021 were enrolled. CE-CBBCT showed substantial agreement (weighted kappa = 0.690) with MRI for BPE evaluation, with good degree of inter-reader reliability on both CE-CBBCT (ICC = 0.712) and MRI (ICC = 0.757). Based on majority reports, BPE levels on CE-CBBCT were lower than MRI (p < 0.001). BPE level on CE-CBBCT was significantly associated with menstrual status (odds ratio, OR = 0.125), breast density (OR = 2.308), and previously treated breast cancer (OR = 0.052) (all p < 0.05). BPE level for premenopausal patients was associated with menstrual cycle, with lower BPE level for the 2nd week of menstrual cycle (OR = 0.246). CONCLUSIONS: CE-CBBCT showed substantial agreement and comparable inter-reader reliability with MRI for BPE evaluation, indicating that the corresponding BI-RADS lexicons could be used to describe BPE level on CE-CBBCT. The 2nd week of menstrual cycle timing is suggested as the optimal examination period for CE-CBBCT. KEY POINTS: • CE-CBBCT showed substantial agreement and comparable inter-reader reliability with MRI for BPE evaluation. • Menstrual status, breast density, and previously treated breast cancer were associated with the BPE level on CE-CBBCT images. • The 2ndweek of the menstrual cycle is suggested as the optimal examination period for CE-CBBCT.


Assuntos
Neoplasias da Mama , Mamografia , Neoplasias da Mama/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Mamografia/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos
5.
Eur Radiol ; 32(3): 1579-1589, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34342694

RESUMO

Dedicated breast CT is an emerging 3D isotropic imaging technology for breast, which overcomes the limitations of 2D compression mammography and limited angle tomosynthesis while providing some of the advantages of magnetic resonance imaging. This first installment in a 2-part review describes the evolution of dedicated breast CT beginning with a historical perspective and progressing to the present day. Moreover, it provides an overview of state-of-the-art technology. Particular emphasis is placed on technical limitations in scan protocol, radiation dose, breast coverage, patient comfort, and image artifact. Proposed methods of how to address these technical challenges are also discussed. KEY POINTS: • Advantages of breast CT include no tissue overlap, improved patient comfort, rapid acquisition, and concurrent assessment of microcalcifications and contrast enhancement. • Current clinical and prototype dedicated breast CT systems differ in acquisition modes, imaging techniques, and detector types. • There are still details to be decided regarding breast CT techniques, such as scan protocol, radiation dose, breast coverage, patient comfort, and image artifact.


Assuntos
Calcinose , Tomografia Computadorizada por Raios X , Mama/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Mamografia , Imagens de Fantasmas
6.
Eur Radiol ; 32(4): 2286-2300, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34476564

RESUMO

Dedicated breast CT is being increasingly used for breast imaging. This technique provides images with no compression, removal of tissue overlap, rapid acquisition, and available simultaneous assessment of microcalcifications and contrast enhancement. In this second installment in a 2-part review, the current status of clinical applications and ongoing efforts to develop new imaging systems are discussed, with particular emphasis on how to achieve optimized practice including lesion detection and characterization, response to therapy monitoring, density assessment, intervention, and implant evaluation. The potential for future screening with breast CT is also addressed. KEY POINTS: • Dedicated breast CT is an emerging modality with enormous potential in the future of breast imaging by addressing numerous clinical needs from diagnosis to treatment. • Breast CT shows either noninferiority or superiority with mammography and numerical comparability to MRI after contrast administration in diagnostic statistics, demonstrates excellent performance in lesion characterization, density assessment, and intervention, and exhibits promise in implant evaluation, while potential application to breast cancer screening is still controversial. • New imaging modalities such as phase-contrast breast CT, spectral breast CT, and hybrid imaging are in the progress of R & D.


Assuntos
Neoplasias da Mama , Calcinose , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/patologia , Calcinose/patologia , Feminino , Humanos , Mamografia/métodos , Tomografia Computadorizada por Raios X/métodos
7.
J Nanobiotechnology ; 20(1): 55, 2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35093073

RESUMO

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) biofilm-associated bacterial infection is the primary cause of nosocomial infection and has long been an ongoing threat to public health. MRSA biofilms are often resistant to multiple antimicrobial strategies, mainly due to the existence of a compact protective barrier; thus, protecting themselves from the innate immune system and antibiotic treatment via limited drug penetration. RESULTS: A hierarchically structured hydrogen sulfide (H2S)-releasing nano-disinfectant was presented, which was composed of a zinc sulfide (ZnS) core as a H2S generator and indocyanine green (ICG) as a photosensitizer. This nano-disinfectant (ICG-ZnS NPs) sensitively responded to the biofilm microenvironment and demonstrated efficient eradication of MRSA biofilms via a synergistic effect of Zn2+, gas molecule-mediated therapy, and hyperthermia. Physically boosted by released H2S and a near-infrared spectroscopy-induced hyperthermia effect, ICG-ZnS NPs destroyed the compactness of MRSA biofilms showing remarkable deep-penetration capability. Moreover, on-site generation of H2S gas adequately ameliorated excessive inflammation, suppressed secretion of inflammatory cytokines, and expedited angiogenesis, therefore markedly accelerating the in vivo healing process of cutaneous wounds infected with MRSA biofilms. CONCLUSION: ICG-ZnS NPs combined with NIR laser irradiation exhibited significant anti-biofilm activity in MRSA biofilms, can accelerate the healing process through deep-penetration and anti-inflammatory effectuation. The proposed strategy has great potential as an alternative to antibiotic treatment when combating multidrug-resistant bacterial biofilms.


Assuntos
Desinfetantes , Staphylococcus aureus Resistente à Meticilina , Infecção dos Ferimentos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Inflamatórios/farmacologia , Biofilmes , Desinfetantes/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Infecção dos Ferimentos/tratamento farmacológico
8.
Acta Radiol ; 63(8): 1023-1031, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34259021

RESUMO

BACKGROUND: Breast density is an independent predictor of breast cancer risk. Quantitative volumetric breast density (QVBD) is expected to provide more information on the prediction of breast cancer risk. PURPOSE: To evaluate the reliability of QVBD measurements based on cone-beam breast computed tomography (CBBCT) images. MATERIAL AND METHODS: A total of 216 breasts were used to evaluate the stability of QVBD measurements based on CBBCT images and the correlations between this volumetric measurement and visual and area-based measurement methods. The intra- and inter-observer consistency of QVBD measurements were compared. Visual breast density (VBD) was evaluated with Breast Imaging Reporting and Data System (BI-RADS) standard on CBBCT images. The correlation between QVBD and VBD was evaluated by Spearman correlation coefficient. Receiver operating characteristic (ROC) curve was used to assess the sensitivity and specificity of the volumetric method in distinguishing dense and non-dense breasts. The correlation between QVBD and quantitative area-based breast density (QABD) was determined with Pearson correlation coefficient. Then, the breast volume measured with CBBCT images was compared with the breast specimen obtained during nipple-sparing mastectomy (NSM) by Pearson correlation coefficient and linear regression. RESULTS: Excellent intra- and inter-observer consistency was found from QVBD measurements. The volumetric method distinguished dense and non-dense breasts at a cutoff value of 9.5%, with 94.5% sensitivity and 77.1% specificity. Positive correlations were found between QVBD and QABD (r=0.890; P<0.001) and between the volume measured with CBBCT images and Archimedes method (r=0.969; P<0.001). CONCLUSION: CBBCT images can evaluate breast density reliably on a continuous scale.


Assuntos
Densidade da Mama , Neoplasias da Mama , Neoplasias da Mama/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Feminino , Humanos , Imageamento Tridimensional , Mamografia/métodos , Mastectomia , Reprodutibilidade dos Testes
9.
Eur Radiol ; 31(4): 2580-2589, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33009590

RESUMO

OBJECTIVES: To investigate the association of contrast-enhanced cone beam breast CT (CE-CBBCT) features, immunohistochemical (IHC) receptors, and molecular subtypes in breast cancer. METHODS: In this retrospective study, patients who underwent preoperative CE-CBBCT and received complete IHC results were analyzed. CE-CBBCT features were evaluated by two radiologists. Observer reproducibility and feature reliability were assessed. The association between CE-CBBCT features, IHC receptors, and molecular subtypes was analyzed using the chi-square, Mann-Whitney, and Kruskal-Wallis tests. Multivariate logistic regression was performed to assess the ability of combined imaging features to discriminate molecular subtypes. ROC curve was used to evaluate prediction performance. RESULTS: A total of 240 invasive cancers identified in 211 women were enrolled. Molecular subtypes of breast cancer were significantly associated with focality number of lesions, lesion type, tumor size, lesion density, internal enhancement pattern, degree of lesion enhancement (ΔHU), mass shape, spiculation, calcifications, calcification distribution, and increased peripheral vascularity of lesion (all p < 0.005), some of which also helped to differentiate IHC receptor status. A multivariate logistic regression model showed that tumor size (odds ratio, OR = 1.244), mass shape (OR = 0.311), spiculation (OR = 0.159), and internal enhancement pattern (OR = 0.227) were associated with differentiation between luminal and non-luminal subtypes (AUC = 0.809). Combined CE-CBBCT features, including lesion type (OR = 0.118), calcifications (OR = 0.181), and ΔHU (OR = 0.962), could be significant indicators of triple-negative versus HER-2-enriched subtypes (AUC = 0.913). CONCLUSIONS: CE-CBBCT features have the potential to help predict IHC receptor status and distinguish molecular subtypes of breast cancer, which could in turn help to develop individual treatment decisions and prognosis predictions. KEY POINTS: • A total of 11 CE-CBBCT features were associated with molecular subtypes, some of which also helped to differentiate IHC receptor status. • Tumor size, irregular mass shape, spiculation, and internal enhancement pattern could help identify luminal subtype. • Lesion type, calcification, and ΔHU could be significant indicators of HER-2- enriched versus triple-negative breast cancers.


Assuntos
Neoplasias da Mama , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Mamografia , Receptor ErbB-2 , Reprodutibilidade dos Testes , Estudos Retrospectivos
10.
Eur Radiol ; 30(6): 3594-3595, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32065280

RESUMO

The original version of this article, published on 03 January 2020, unfortunately contained two mistakes.

11.
Eur Radiol ; 30(5): 2731-2739, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31900700

RESUMO

OBJECTIVES: To identify the relationship between human epidermal growth factor receptor 2 (HER2) status and cone-beam breast CT (CBBCT) characteristics in surgically resected breast cancer. METHODS: Preoperative CBBCT of patients with BI-RADS 4 or 5 lesions identified on mammography or ultrasound and dense or very dense breast tissue were retrospectively evaluated in 181 surgically resected breast cancer (triple-negative excluded) between May 2012 and November 2014. A set of CBBCT descriptors was semiquantitatively assessed by consensus double reading. Reader reproducibility was analyzed. Multivariable logistic regression analysis using backward elimination (BEA) with the Wald criterion was performed to identify independent predictive factors of harboring HER2/neu. Principle component analysis (PCA) was used to determine characteristics that might differentiate HER2 status. Receiver operating characteristic (ROC) curve analyses were conducted to determine the predictive capability. RESULTS: HER2 positive was found in 101 (55.8%) of 181 patients. Inter-observer agreement was high for characteristics' assessment. Based on BEA, pathologic grade, maximum dimension, lobulation, ΔCT, and calcification morphology were confirmed as independent predictive factors of HER2/neu overexpression. PCA showed that calcification- and border-related characteristics were the most important for differentiation. ROC curve analyses showed that CBBCT features (AUC = 0.853) were superior to clinicopathologic features (AUC = 0.613, p < 0.001) and comparable with combination (AUC = 0.856, p = 0.866). CONCLUSIONS: CBBCT features could be used to prognosticate HER2 status independently, which are potentially complementary to histopathologic result and helpful in guiding biopsy. KEY POINTS: • Dmax, lobulation, ΔCT, and calcification morphology are independent predictors of HER2 status. • CBBCT features are superior to clinicopathologic features in HER2+/- discrimination. • CBBCT features are comparable with combination with clinicopathologic features in HER2+/- discrimination.


Assuntos
Neoplasias da Mama/diagnóstico , Tomografia Computadorizada de Feixe Cônico/métodos , Mamografia/métodos , Receptor ErbB-2/biossíntese , Adulto , Idoso , Biomarcadores Tumorais/biossíntese , Biópsia , Densidade da Mama , Neoplasias da Mama/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos
14.
Gland Surg ; 13(3): 281-296, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38601282

RESUMO

Background: Accurate preoperative assessment of tumor size is important in developing a surgical plan for breast cancer. The purpose of this study was to evaluate the accuracy of cone-beam breast computed tomography (CBBCT) and magnetic resonance imaging (MRI) in the assessment of tumor size and to analyze the factors influencing the discordance. Methods: In this retrospective study, patients with breast cancer who underwent preoperative contrast-enhanced CBBCT (CE-CBBCT) and dynamic contrast-enhanced MRI (DCE-MRI) and received a complete pathologic diagnosis from August 2020 to December 2021 were included, using the pathological result as the gold standard. Two radiologists assessed the CBBCT and MRI features and measured the tumor size with a 2-week washout period. Intraclass correlation coefficient (ICC) and Bland-Altman analyses were used to assess inter-observer reproducibility and agreement based on CBBCT, MRI and pathology. Univariate analyses of differences in clinical, pathological and CBBCT/MRI features between the concordant and discordant groups was performed using the t-test, Mann-Whitney U-test, Chi-squared test and Fisher's exact test. Multivariate analyses were used to identify factors associated with discordance of CBBCT/MRI with pathology. Results: A total of 115 female breast cancer patients (115 lesions) were included. All patients had a single malignant tumor of the unilateral breast. The reproducibility and the agreement ranged from moderate to excellent (ICC =0.607-0.983). Receiver operating characteristic (ROC) analyses showed that the cut-off values of CBBCT-pathology and MRI-pathology discordance were 2.25 and 2.65 cm, respectively. CBBCT/MRI-pathology concordance was significantly associated with the extent of pathology, lesion type, presence of calcification, human epidermal growth factor receptor 2 (HER2) status and fatty infiltration (P<0.05). In lesions containing calcification, the difference of CBBCT-pathology was significantly smaller than MRI-pathology (P=0.021). Non-mass enhancement (NME) was the main predictor of CBBCT- or MRI-pathology discordance [odds ratio (OR) =3.293-6.469, P<0.05], and HER2 positivity was a predictor of CBBCT-pathology discordance (OR =3.514, P=0.019). Conclusions: CBBCT and MRI have comparable accuracy in measurement of tumor size, and CBBCT is advantageous in assessing the size of calcified lesions. NME and HER2 positivity are significant predictors of CBBCT-pathology discordance. This suggests that CBBCT might serve as an alternative imaging technique to assess tumor size when patients do not tolerate MRI.

15.
Acad Radiol ; 30(9): 1805-1815, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36610931

RESUMO

RATIONALE AND OBJECTIVES: To compare the accuracy of preoperative contrast-enhanced cone beam breast CT (CE-CBBCT) and MRI in assessment of residual tumor after neoadjuvant chemotherapy (NAC). MATERIALS AND METHODS: Residual tumor assessments in 91 female patients were performed on preoperative CE-CBBCT and MRI images after NAC. The agreements of tumor size between imaging and pathology were tested by Intraclass Correlation Coefficient (ICC). Subgroup analyses were set according to ductal carcinoma in situ (DCIS), calcifications and molecular subtypes. Correlated-samples Wilcoxon Signed-rank test was used to analyze the difference between imaging and pathology in total and subgroups. AUC, sensitivity, specificity, PPV, and NPV were calculated to compare the performance of CE-CBBCT and MRI in predicting pathological complete response (pCR). RESULTS: Comparing with pathology, the agreement on CE-CBBCT was good (ICC = 0.64, 95% CI, 0.35-0.78), whereas on MRI was moderate (ICC = 0.59, 95% CI, 0.36-0.77), and overestimation on CE-CBBCT was less than that on MRI (median (interquartile range, IQR): 0.24 [0.00, 1.31] cm vs. 0.67 [0.00, 1.81] cm; p = 0.000). In subgroup analysis, CE-CBBCT showed superior accuracy than MRI when residual DCIS (p = 0.000) and calcifications (p = 0.000) contained, as well as luminal A (p = 0.043) and luminal B (p = 0.009) breast cancer. CE-CBBCT and MRI performed comparable in predicting pCR, AUCs were 0.749 and 0.733 respectively (p > 0.05). CONCLUSION: CE-CBBCT showed superior accuracy in assessment of residual tumor compared with MRI, especially when residual DCIS or calcifications contained and luminal subtype. The performance of preoperative CE-CBBCT in predicting pCR was comparable to MRI. CE-CBBCT could be an alternative method used for preoperative assessment after NAC.


Assuntos
Neoplasias da Mama , Calcinose , Carcinoma Intraductal não Infiltrante , Feminino , Humanos , Terapia Neoadjuvante/métodos , Carcinoma Intraductal não Infiltrante/patologia , Neoplasia Residual/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Tomografia Computadorizada de Feixe Cônico/métodos , Imageamento por Ressonância Magnética/métodos
16.
Neural Netw ; 153: 152-163, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35724477

RESUMO

In this paper, two novel and general predefined-time stability lemmas are given and applied to the predefined-time synchronization problem of memristive complex-valued bidirectional associative memory neural networks (MCVBAMNNs). Firstly, different from the generally fixed-time stability lemma, the setting of an adjustable time parameter in the derived predefined-time stability lemma causes it to be more flexible and more general. Secondly, the model studied in the complex-valued BAM neural networks model, which is different from the previous discussion of the real part and imaginary part respectively. It is more practical to study the complex-valued nonseparation. Thirdly, two effective controllers are designed to realize the synchronization performance of BAM neural networks based on the predefined-time stability, and the analysis is given based on general predefined-time synchronization. Finally, the correctness of the theoretical derivation is verified by numerical simulation. A secure communication scheme based on predefined-time synchronization of MCVBAMNNs is proposed, and the effectiveness and superiority of the results are proved.


Assuntos
Redes Neurais de Computação , Fatores de Tempo
17.
Front Neurorobot ; 16: 1000426, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36325047

RESUMO

This paper investigates the fixed-time synchronization and the predefined-time synchronization of memristive complex-valued bidirectional associative memory neural networks (MCVBAMNNs) with leakage time-varying delay. First, the proposed neural networks are regarded as two dynamic real-valued systems. By designing a suitable feedback controller, combined with the Lyapunov method and inequality technology, a more accurate upper bound of stability time estimation is given. Then, a predefined-time stability theorem is proposed, which can easily establish a direct relationship between tuning gain and system stability time. Any predefined time can be set as controller parameters to ensure that the synchronization error converges within the predefined time. Finally, the developed chaotic MCVBAMNNs and predefined-time synchronization technology are applied to image encryption and decryption. The correctness of the theory and the security of the cryptographic system are verified by numerical simulation.

18.
Asian J Pharm Sci ; 17(5): 713-727, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36382303

RESUMO

Photothermal therapy (PTT) has brought hope for cancer treatments, with hyperthermia-induced immunogenic cell death (ICD), which is a critical part of therapeutically induced antitumor immune responses. Limited immune stimulation response in PTT is the primary reason for incomplete tumor ablation, therefore demonstrating urgent requirements for ICD amplifier. Herein, a sub-10 nm supramolecular nanoassembly was formed by co-assembly of clinically approved aluminum adjuvant and commonly used indocyanine green (ICG) under the assistance of lignosulfonate (LS, a green and sustainable multifunctional lignin derivative) for localized photothermal-immunotherapy of breast cancer. The overall results revealed that LS-Al-ICG is capable of inducing amplified ICD, efficiently eliciting solid immune responses through dendritic cells (DCs) activation and cytotoxic T-cell responses initiation for tumor killing. Moreover, anti-PD-1 therapy blocked the PD-1 pathway and led to remarkable anti-tumor efficacy against laser-irradiated primary tumors and distant tumors by potentiating systemic tumor specific T cell immunity. The results of this study demonstrate a handy and extensible approach for engineering green natural lignin nanoparticles for cancer immunotherapy, which shows promise for delivering other therapeutics in biomedical applications.

19.
Int J Pharm ; 623: 121918, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35716973

RESUMO

Hydroxy-safflower yellow A (HSYA) is the chief component of safflower against myocardial ischemia (MI), and belongs to biopharmaceutics classification system (BCS) III drugs. Its structure contains multiple hydroxyl groups, contributing to its high polarity and poor oral bioavailability. The main objective of this study was to probe the potential of oral penetration enhancer n-[8-(2-hydroxybenzoyl) amino] sodium octanoate (SNAC) and cationic copolymer Eudragit®EPO (EPO) to promote absorption of HSYA. HSYA composites (SNAC-HSYA-EPO) were formed by hydrogen bonding and van der Waals force. SNAC-HSYA-EPO has biocompatibility, and can improve the membrane fluidity, uptake, transport, and penetration of Caco-2 cells. The mechanism of promoting of SNAC-HSYA-EPO may be related to energy and P-glycoprotein (P-gp) when compared with the inhibitor NaN3 and verapamil group. In the pharmacokinetic (PK) results, SNAC-HSYA-EPO significantly improved oral bioavailability. Pharmacodynamics (PD) results determined that SNAC-HSYA-EPO could improve the symptoms of MI. The mechanism of the SNAC-HSYA-EPO anti-MI is related to alleviating inflammation and anti-apoptosis to protect the heart. In summary, SNAC-HSYA-EPO prepared in this study possessed a complete appearance, high recombination rate and excellent oral permeability promoting ability. SNAC-HSYA-EPO has the potential to improve oral bioavailability and further enhance the anti-MI effect of HSYA.


Assuntos
Chalcona , Doença da Artéria Coronariana , Isquemia Miocárdica , Células CACO-2 , Chalcona/análogos & derivados , Chalcona/farmacologia , Humanos , Isquemia , Isquemia Miocárdica/tratamento farmacológico , Permeabilidade
20.
Front Neurorobot ; 15: 783809, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35002668

RESUMO

This paper explores the realization of a predefined-time synchronization problem for coupled memristive neural networks with multi-links (MCMNN) via nonlinear control. Several effective conditions are obtained to achieve the predefined-time synchronization of MCMNN based on the controller and Lyapunov function. Moreover, the settling time can be tunable based on a parameter designed by the controller, which is more flexible than fixed-time synchronization. Then based on the predefined-time stability criterion and the tunable settling time, we propose a secure communication scheme. This scheme can determine security of communication in the aspect of encrypting the plaintext signal with the participation of multi-links topology and coupled form. Meanwhile, the plaintext signals can be recovered well according to the given new predefined-time stability theorem. Finally, numerical simulations are given to verify the effectiveness of the obtained theoretical results and the feasibility of the secure communication scheme.

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