Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
1.
Radiol Artif Intell ; 5(6): e220299, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38074785

RESUMO

Purpose: To externally evaluate a mammography-based deep learning (DL) model (Mirai) in a high-risk racially diverse population and compare its performance with other mammographic measures. Materials and Methods: A total of 6435 screening mammograms in 2096 female patients (median age, 56.4 years ± 11.2 [SD]) enrolled in a hospital-based case-control study from 2006 to 2020 were retrospectively evaluated. Pathologically confirmed breast cancer was the primary outcome. Mirai scores were the primary predictors. Breast density and Breast Imaging Reporting and Data System (BI-RADS) assessment categories were comparative predictors. Performance was evaluated using area under the receiver operating characteristic curve (AUC) and concordance index analyses. Results: Mirai achieved 1- and 5-year AUCs of 0.71 (95% CI: 0.68, 0.74) and 0.65 (95% CI: 0.64, 0.67), respectively. One-year AUCs for nondense versus dense breasts were 0.72 versus 0.58 (P = .10). There was no evidence of a difference in near-term discrimination performance between BI-RADS and Mirai (1-year AUC, 0.73 vs 0.68; P = .34). For longer-term prediction (2-5 years), Mirai outperformed BI-RADS assessment (5-year AUC, 0.63 vs 0.54; P < .001). Using only images of the unaffected breast reduced the discriminatory performance of the DL model (P < .001 at all time points), suggesting that its predictions are likely dependent on the detection of ipsilateral premalignant patterns. Conclusion: A mammography DL model showed good performance in a high-risk external dataset enriched for African American patients, benign breast disease, and BRCA mutation carriers, and study findings suggest that the model performance is likely driven by the detection of precancerous changes.Keywords: Breast, Cancer, Computer Applications, Convolutional Neural Network, Deep Learning Algorithms, Informatics, Epidemiology, Machine Learning, Mammography, Oncology, Radiomics Supplemental material is available for this article. © RSNA, 2023See also commentary by Kontos and Kalpathy-Cramer in this issue.

2.
Magn Reson Imaging ; 104: 9-15, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37611646

RESUMO

PURPOSE: To assess whether measurement of the bilateral asymmetry of semiquantitative and quantitative perfusion parameters from ultrafast dynamic contrast-enhanced MRI (DCE-MRI), allows early prediction of pathologic response after neoadjuvant chemotherapy (NAC) in patients with HER2+ breast cancer. MATERIALS AND METHODS: Twenty-eight female patients with HER2+ breast cancer treated with NAC who underwent pre-NAC ultrafast DCE-MRI (3-9 s/phase) were enrolled for this study. Four semiquantitative and two quantitative parenchymal parameters were calculated for each patient. Ipsilateral/contralateral (I/C) ratio (for four parameters) and the difference between (for two parameters) ipsi- and contra-lateral parenchymal kinetic parameters (kBPE) were compared for patients with pathologic complete response (pCR) and those having residual disease. Lasso regression with leave-one-out cross validation was used to determine the optimal combination of parameters for a regression model and multivariable logistic regression was used to identify independent predictors for pCR. Chi-squared test, two-sided t-test and Kruskal-Wallis test were used. RESULTS: The Ktrans I/C ratio cutoff value of 1.11 had a sensitivity of 83.3% and specificity of 75% for pCR. The ve I/C ratio cutoff value of 1.1 had a sensitivity of 75% and specificity of 81.3% for pCR. The area under the receiver operating characteristic curve of the three-kBPE parameter model, including initial area under the enhancement curve (AUC30) I/C ratio, KtransI/C ratio and ve I/C ratio, was 0.89 with sensitivity of 91.7% at specificity of 81.3%. CONCLUSION: Quantitative assessment of bilateral asymmetry kBPE from pre-NAC ultrafast DCE-MRI can predict pCR in patients with HER2+ breast cancer.

3.
Ann Surg Oncol ; 28(10): 5513-5524, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34333705

RESUMO

BACKGROUND: Two-dimensional (2D) specimen radiography (SR) and tomosynthesis (DBT) for breast cancer yield data that lack high-depth resolution. A volumetric specimen imager (VSI) was developed to provide full-3D and thin-slice cross-sectional visualization at a 360° view angle. The purpose of this prospective trial was to compare VSI, 2D SR, and DBT interpretation of lumpectomy margin status with the final pathologic margin status of breast lumpectomy specimens. METHODS: The study enrolled 200 cases from two institutions. After standard imaging and interpretation was performed, the main lumpectomy specimen was imaged with the VSI device. Image interpretation was performed by three radiologists after surgery based on VSI, 2D SR, and DBT. A receiver operating characteristic (ROC) curve was created for each method. The area under the curve (AUC) was computed to characterize the performance of the imaging method interpreted by each user. RESULTS: From 200 lesions, 1200 margins were interpreted. The AUC values of VSI for the three radiologists were respectively 0.91, 0.90, and 0.94, showing relative improvement over the AUCs of 2D SR by 54%, 13%, and 40% and DBT by 32% and 11%, respectively. The VSI has sensitivity ranging from 91 to 94%, specificity ranging from 81 to 85%, a positive predictive value ranging from 25 to 30%, and a negative predicative value of 99%. CONCLUSIONS: The ROC curves of the VSI were higher than those of the other specimen imaging methods. Full-3D specimen imaging can improve the correlation between the main lumpectomy specimen margin status and surgical pathology. The findings from this study suggest that using the VSI device for intraoperative margin assessment could further reduce the re-excision rates for women with malignant disease.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Mama , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Estudos Transversais , Feminino , Humanos , Mamografia , Estudos Prospectivos
4.
J Biosci ; 452020.
Artigo em Inglês | MEDLINE | ID: mdl-32975231

RESUMO

In this study we have investigated the effects of a tumour suppressor microRNA, miR-214, on gene expression in HPV-positive (CaSki) and HPV-negative cervical cancer cells (C33A) by RNA sequencing using next generation sequencing. The HPV-positive and HPV-negative cervical cancer cells were either miR-214- knocked-out or miR-214-overexpressed. Gene expression analysis showed that a total of 904 genes were upregulated and 365 genes were downregulated between HPV-positive and HPV-negative cervical cancer cells with a fold change of +/- 2. Furthermore, 11 differentially expressed and relevant genes (TNFAIP3, RAB25, MET, CYP1B1, NDRG1, CD24, LOXL2, CD44, PMS2, LATS1 and MDM1) which showed a fold change of +/-5 were selected to confirm by real-time PCR. This study represents the first report of miR-214 on global gene expression in the context of HPV.


Assuntos
MicroRNAs/genética , Proteínas de Neoplasias/genética , Infecções por Papillomavirus/genética , Transcriptoma , Neoplasias do Colo do Útero/genética , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Antígeno CD24/genética , Antígeno CD24/metabolismo , Sistemas CRISPR-Cas , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MicroRNAs/agonistas , MicroRNAs/antagonistas & inibidores , MicroRNAs/metabolismo , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Endonuclease PMS2 de Reparo de Erro de Pareamento/metabolismo , Proteínas de Neoplasias/metabolismo , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
5.
Genomics ; 112(2): 1490-1499, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31465786

RESUMO

In this study, we investigate the effect of one such micro RNA, miR-214 which is frequently down-regulated in cervical cancer. In this study, we either CRISPR knocked out or overexpressed miR-214 in cervical cancer cells and analyzed the global mRNA expression by Next Generation Sequencing (NGS) It was observed that a total of 108 genes were upregulated and 178 downregulated between the samples, above and below the baseline respectively. Gene Ontology and KEGG pathway analysis reveal distinct biological processes and pathways. Analysis of gene regulatory networks also gave different network patterns in the two samples. We confirmed the RNA sequencing data for 10 genes; IFIF27, SMAD3, COX11, TP53INP1, ABL2, FGF8, TNFAIP3, NRG1, SP3 and MDM4 by Real-time PCR. This is the first report on the effect of miR-214 on global mRNA profile in cervical cancer cells. This study also reports new biomarkers for cervical cancer prognosis.


Assuntos
Biomarcadores Tumorais/genética , MicroRNAs/genética , Transcriptoma , Neoplasias do Colo do Útero/genética , Biomarcadores Tumorais/metabolismo , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Inativação de Genes , Humanos , MicroRNAs/metabolismo
6.
J Am Coll Radiol ; 17(2): 238-247, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31628897

RESUMO

OBJECTIVE: To evaluate the impact of comorbid conditions and age on mammography use. METHODS: We used data from the 2011 to 2015 Medical Expenditure Panel Survey, which contained records for 40,752 women over the age of 40. Use was defined as a mammogram within the previous 1 or 2 years, analyzed separately. A logit model was employed to evaluate associations between use and comorbidities and age. Statistical significance was defined by a P < .05 by two-sided test. RESULTS: Of the 36,575 women in our study sample, 45.9%, 43.6%, 3.9%, and 5.7% reported a history of hypertension (HTN), hyperlipidemia (HLD), prior heart attack (MI), and prior stroke, respectively. Among women without a comorbid condition, there was 47.3% annual mammography use. HTN and HLD were associated with increased use (2.5 and 6.8 percentage points [pp], P< .01). In comparison, prior MI was associated with decreased annual use (-8.2 pp, P < .01). Prior stroke was not significantly associated with annual mammography (-1.5 pp, P = .42). Results were similar for biennial use. The age trend in use showed that the age with maximum screening use was approximately 60 years. DISCUSSION: Mammography use was higher in patients with HTN and HLD and lower in patients with prior MI and stroke, which may reflect differences in comorbidity-related general health care use. Use increased until it peaked around age 60. An understanding of how mammography use naturally evolves as people age may help better target specific populations and improve overall use of preventive care.


Assuntos
Neoplasias da Mama , Mamografia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Comorbidade , Feminino , Humanos , Modelos Logísticos , Programas de Rastreamento , Pessoa de Meia-Idade , Fatores de Tempo
7.
J Med Imaging (Bellingham) ; 6(3): 034502, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31592438

RESUMO

The purpose of this study was to evaluate breast MRI radiomics in predicting, prior to any treatment, the response to neoadjuvant chemotherapy (NAC) in patients with invasive lymph node (LN)-positive breast cancer for two tasks: (1) prediction of pathologic complete response and (2) prediction of post-NAC LN status. Our study included 158 patients, with 19 showing post-NAC complete pathologic response (pathologic TNM stage T0,N0,MX) and 139 showing incomplete response. Forty-two patients were post-NAC LN-negative, and 116 were post-NAC LN-positive. We further analyzed prediction of response by hormone receptor subtype of the primary cancer (77 hormone receptor-positive, 39 HER2-enriched, 38 triple negative, and 4 cancers with unknown receptor status). Only pre-NAC MRIs underwent computer analysis, initialized by an expert breast radiologist indicating index cancers and metastatic axillary sentinel LNs on DCE-MRI images. Forty-nine computer-extracted radiomics features were obtained, both for the primary cancers and for the metastatic sentinel LNs. Since the dataset contained MRIs acquired at 1.5 T and at 3.0 T, we eliminated features affected by magnet strength using the Mann-Whitney U-test with the null-hypothesis that 1.5 T and 3.0 T samples were selected from populations having the same distribution. Bootstrapping and ROC analysis were used to assess performance of individual features in the two classification tasks. Eighteen features appeared unaffected by magnet strength. Pre-NAC tumor features generally appeared uninformative in predicting response to therapy. In contrast, some pre-NAC LN features were able to predict response: two pre-NAC LN features were able to predict pathologic complete response (area under the ROC curve (AUC) up to 0.82 [0.70; 0.88]), and another two were able to predict post-NAC LN-status (AUC up to 0.72 [0.62; 0.77]), respectively. In the analysis by a hormone receptor subtype, several potentially useful features were identified for predicting response to therapy in the hormone receptor-positive and HER2-enriched cancers.

8.
Clin Cancer Res ; 25(6): 1786-1794, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30154229

RESUMO

PURPOSE: To establish a cohort of high-risk women undergoing intensive surveillance for breast cancer.Experimental Design: We performed dynamic contrast-enhanced MRI every 6 months in conjunction with annual mammography (MG). Eligible participants had a cumulative lifetime breast cancer risk ≥20% and/or tested positive for a pathogenic mutation in a known breast cancer susceptibility gene. RESULTS: Between 2004 and 2016, we prospectively enrolled 295 women, including 157 mutation carriers (75 BRCA1, 61 BRCA2); participants' mean age at entry was 43.3 years. Seventeen cancers were later diagnosed: 4 ductal carcinoma in situ (DCIS) and 13 early-stage invasive breast cancers. Fifteen cancers occurred in mutation carriers (11 BRCA1, 3 BRCA2, 1 CDH1). Median size of the invasive cancers was 0.61 cm. No patients had lymph node metastasis at time of diagnosis, and no interval invasive cancers occurred. The sensitivity of biannual MRI alone was 88.2% and annual MG plus biannual MRI was 94.1%. The cancer detection rate of biannual MRI alone was 0.7% per 100 screening episodes, which is similar to the cancer detection rate of 0.7% per 100 screening episodes for annual MG plus biannual MRI. The number of recalls and biopsies needed to detect one cancer by biannual MRI were 2.8 and 1.7 in BRCA1 carriers, 12.0 and 8.0 in BRCA2 carriers, and 11.7 and 5.0 in non-BRCA1/2 carriers, respectively. CONCLUSIONS: Biannual MRI performed well for early detection of invasive breast cancer in genomically stratified high-risk women. No benefit was associated with annual MG screening plus biannual MRI screening.See related commentary by Kuhl and Schrading, p. 1693.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/diagnóstico , Detecção Precoce de Câncer/métodos , Imageamento por Ressonância Magnética/métodos , Programas de Rastreamento/métodos , Adulto , Biópsia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Predisposição Genética para Doença , Humanos , Mamografia , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Estudos Prospectivos
9.
Clin Imaging ; 48: 69-73, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29035756

RESUMO

PURPOSE: To evaluate whether the disease status of the pre-neoadjuvant chemotherapy (NAC) core biopsied lymph node (preNACBxLN) in patients with node positive breast cancer corresponds to nodal status of all surgically retrieved lymph nodes (LNs) post-NAC and whether wire localization of this LN is feasible. MATERIALS AND METHODS: HIPPA compliant IRB approved retrospective study including breast cancer patients (a.) with preNACBxLN confirmed metastases, (b.) who received NAC, and (c.) underwent wire localization of the preNACBxLN. Electronic medical records were reviewed. Fisher's exact test was used to compare differences in residual disease post-NAC among breast cancer subtypes. RESULTS: 28 women with node positive breast cancer underwent ultrasound guided wire localization of the preNACBxLN, without complication. There was no evidence of residual nodal disease for 16 patients, with mean 4.4 (median 4) LNs resected. 12 patients had residual nodal metastases, with mean 9.2 (median 7) LNs resected and mean 2.3 (median 2) LNs with tumor involvement. 11 patients had metastases detected within the localized LN. One patient had micrometastasis in a sentinel LN, despite no residual disease in the preNACBxLN. Patients with luminal A/B breast cancer more often had residual nodal metastases (86%) at pathology, as compared to patients with HER2+ (20%) and Triple Negative breast cancer (50%), though not quite achieving statistical significance (p=0.055). CONCLUSION: Ultrasound guided wire localization of the preNACBxLN is feasible and may improve detection of residual tumor in patients post-NAC.


Assuntos
Neoplasias da Mama/patologia , Linfonodos/patologia , Biópsia de Linfonodo Sentinela/métodos , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila/patologia , Neoplasias da Mama/tratamento farmacológico , Estudos de Viabilidade , Feminino , Humanos , Metástase Linfática/diagnóstico , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estudos Retrospectivos
10.
Mol Ther Nucleic Acids ; 9: 349-364, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29246314

RESUMO

Inhibition of the interaction between p53 and HDM2 is an effective therapeutic strategy in cancers that harbor a wild-type p53 protein such as retinoblastoma (RB). Nanoparticle-based delivery of therapeutic molecules has been shown to be advantageous in localized delivery, including to the eye, by overcoming ocular barriers. In this study, we utilized biocompatible gold nanoparticles (GNPs) to deliver anti-HDM2 peptide to RB cells. Characterization studies suggested that GNP-HDM2 was stable in biologically relevant solvents and had optimal cellular internalization capability, the primary requirement of any therapeutic molecule. GNP-HDM2 treatment in RB cells in vitro suggested that they function by arresting RB cells at the G2M phase of the cell cycle and initiating apoptosis. Analysis of molecular changes in GNP-HDM2-treated cells by qRT-PCR and western blotting revealed that the p53 protein was upregulated; however, transactivation of its downstream targets was minimal, except for the PUMA-BCl2 and Bax axis. Global gene expression and in silico bioinformatic analysis of GNP-HDM2-treated cells suggested that upregulation of p53 might presumptively mediate apoptosis through the induction of p53-inducible miRNAs.

11.
Clin Imaging ; 45: 96-104, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28645096

RESUMO

Incidental focal FDG uptake in the breast or axilla on PET/CT performed for evaluation of extra-mammary primary disease presents a diagnostic challenge. Radiologists must consider a broad differential diagnosis, assess clinical history, and judiciously employ other imaging modalities such as mammography, ultrasound and MRI in the pursuit of findings which help narrow the differential diagnosis. Tissue sampling may be reserved for nondiagnostic imaging scenarios.


Assuntos
Axila/diagnóstico por imagem , Doenças Mamárias/diagnóstico , Mama/diagnóstico por imagem , Fluordesoxiglucose F18/farmacologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Diagnóstico Diferencial , Feminino , Humanos , Compostos Radiofarmacêuticos/farmacologia
12.
Genom Data ; 3: 8-14, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26484141

RESUMO

The role of Mithramycin as an anticancer drug has been well studied. Sarcoma is a type of cancer arising from cells of mesenchymal origin. Though incidence of sarcoma is not of significant percentage, it becomes vital to understand the role of Mithramycin in controlling tumor progression of sarcoma. In this article, we have analyzed the global gene expression profile changes induced by Mithramycin in two different sarcoma lines from whole genome gene expression profiling microarray data. We have found that the primary mode of action of Mithramycin is by global repression of key cellular processes and gene families like phosphoproteins, kinases, alternative splicing, regulation of transcription, DNA binding, regulation of histone acetylation, negative regulation of gene expression, chromosome organization or chromatin assembly and cytoskeleton.

13.
FEBS Open Bio ; 4: 987-95, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25473595

RESUMO

Mithramycin (MTR) is a clinically approved DNA-binding antitumor antibiotic currently in Phase 2 clinical trials at National Institutes of Health for treatment of osteosarcoma. In view of the resurgence in the studies of this generic antibiotic as a human medicine, we have examined the binding properties of MTR with the integral component of chromatin - histone proteins - as a part of our broad objective to classify DNA-binding molecules in terms of their ability to bind chromosomal DNA alone (single binding mode) or both histones and chromosomal DNA (dual binding mode). The present report shows that besides DNA, MTR also binds to core histones present in chromatin and thus possesses the property of dual binding in the chromatin context. In contrast to the MTR-DNA interaction, association of MTR with histones does not require obligatory presence of bivalent metal ion like Mg(2+). As a consequence of its ability to interact with core histones, MTR inhibits histone H3 acetylation at lysine 18, an important signature of active chromatin, in vitro and ex vivo. Reanalysis of microarray data of Ewing sarcoma cell lines shows that upon MTR treatment there is a significant down regulation of genes, possibly implicating a repression of H3K18Ac-enriched genes apart from DNA-binding transcription factors. Association of MTR with core histones and its ability to alter post-translational modification of histone H3 clearly indicates an additional mode of action of this anticancer drug that could be implicated in novel therapeutic strategies.

14.
AJR Am J Roentgenol ; 202(2): 289-92, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24450667

RESUMO

OBJECTIVE: The purposes of this study were to assess the importance of a personal history of breast cancer as a risk factor for patients referred for screening breast MRI and to evaluate the importance of this risk factor compared with family history. MATERIALS AND METHODS: A retrospective review of screening breast MRI performed from 2004 to 2012 included a total of 702 patients, 465 of whom had undergone annual MRI and 237 of whom had undergone MRI every 6 months as part of a research protocol. RESULTS: Of the patients screened, 208 had a personal history of breast cancer, and 345 had a family history as the sole risk factor. An additional 97 patients had both risk factors. The absolute risk for detection of breast cancer at screening MRI among patients with a personal history of cancer was 2.8% (95% CI, 0.6-5.2%). The absolute risk for patients with a strong family history of cancer was 2.0% (95% CI, 0.5-3.5%). The relative risk for detection of breast cancer given a personal history was 1.42 (95% CI, 0.48-4.17) compared with family history. The relative risk when both risk factors were present compared with having only a family history was 3.04 (95% CI, 1.05-8.86). CONCLUSION: A personal history of breast cancer is an important risk factor for the development of subsequent breast cancer. Given the results, consideration should be given to MRI screening of patients with a personal history of breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Programas de Rastreamento , Meglumina/análogos & derivados , Pessoa de Meia-Idade , Compostos Organometálicos , Estudos Retrospectivos , Fatores de Risco
15.
Acad Radiol ; 20(11): 1399-404, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24119352

RESUMO

PURPOSE: To compare magnetic resonance imaging (MRI) and ultrasound (US) for axillary lymph node (LN) staging in breast cancer patients in an observer-performance study. MATERIALS AND METHODS: An observer-performance study was conducted with five breast radiologists reviewing 50 consecutive patients of newly diagnosed invasive breast cancer with the use of ipsilateral axillary MRI and US. LN status was pathologically proved in all patients. Each observer reviewed the images in two separate sessions: one for MRI and the other for US. Observers were asked to indicate their confidence of the presence of at least one ipsilateral metastatic LN on a quasi-continuous rating scale and whether they recommend percutaneous biopsy preoperatively. Receiver operating characteristic (ROC) analysis and area under the ROC curve were used to characterize diagnostic performance. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated from whether observers recommended biopsy. RESULTS: There were no statistically significant differences in each observer's performance between MRI and US, or in the performance of all observers as a group, in terms of ROC analysis. There were no statistically significant differences in sensitivity, specificity, PPV, or NPV between MRI and US, but there were statistically significant improvements in specificity and PPV from either MRI or US alone to MRI and US combined. CONCLUSIONS: Observer performance on MRI and US are comparable for axillary LN staging. When US and MRI are concordant for positive findings, higher specificity and PPV can be obtained.


Assuntos
Axila/patologia , Neoplasias da Mama/patologia , Metástase Linfática/patologia , Imageamento por Ressonância Magnética/métodos , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico por imagem , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Sensibilidade e Especificidade
16.
Acad Radiol ; 18(12): 1467-74, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21962476

RESUMO

RATIONALE AND OBJECTIVES: The aims of this study were to evaluate high spectral and spatial resolution (HiSS) magnetic resonance imaging (MRI) for the diagnosis of breast cancer without the injection of contrast media by comparing the performance of precontrast HiSS images to that of conventional contrast-enhanced, fat-suppressed, T1-weighted images on the basis of image quality and in the task of classifying benign and malignant breast lesions. MATERIALS AND METHODS: Ten benign and 44 malignant lesions were imaged at 1.5 T with HiSS (precontrast administration) and conventional fat-suppressed imaging (3-10 minutes after contrast administration). This set of 108 images, after randomization, was evaluated by three experienced radiologists blinded to the imaging technique. Breast Imaging Reporting and Data System morphologic criteria (lesion shape, lesion margin, and internal signal intensity pattern) and final assessment were used to measure reader performance. Image quality was evaluated on the basis of boundary delineation and quality of fat suppression. An overall probability of malignancy was assigned to each lesion for HiSS and conventional images separately. RESULTS: On boundary delineation and quality of fat suppression, precontrast HiSS scored similarly to conventional postcontrast MRI. On benign versus malignant lesion separation, there was no statistically significant difference in receiver-operating characteristic performance between HiSS and conventional MRI, and HiSS met a reasonable noninferiority condition. CONCLUSIONS: Precontrast HiSS imaging is a promising approach for showing lesion morphology without blooming and other artifacts caused by contrast agents. HiSS images could be used to guide subsequent dynamic contrast-enhanced MRI scans to maximize spatial and temporal resolution in suspicious regions. HiSS MRI without contrast agent injection may be particularly important for patients at risk for contrast-induced nephrogenic systemic fibrosis or allergic reactions.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética/métodos , Idoso , Doenças Mamárias/diagnóstico , Neoplasias da Mama/diagnóstico por imagem , Meios de Contraste , Gorduras , Feminino , Humanos , Aumento da Imagem , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia
17.
AJR Am J Roentgenol ; 195(2): 381-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20651193

RESUMO

OBJECTIVE: The purpose of this article is to determine whether enhancement of nodular foci within hemangiomas is homogeneous and matches blood vessels at different phases on contrast-enhanced MDCT. MATERIALS AND METHODS: Multiphase (unenhanced, arterial, portal venous, and delayed phases) MDCT images of 58 hemangiomas were reviewed by two radiologists. Nodular-enhancing foci within hemangiomas were evaluated for enhancement pattern and were subjectively compared with enhancement of the aorta, inferior vena cava, hepatic vein, and portal vein for each contrast-enhanced phase. Both readers measured CT attenuation of enhancing nodules and vessels at each phase, and enhancement of nodules and vessels was compared. RESULTS: Qualitative analysis showed heterogeneously enhancing nodules in 79.3% and 65.5% of hemangiomas in the arterial phase and in 74.1% and 53.4% of hemangiomas in the portal venous phase, according to readers 1 and 2, respectively. In the arterial phase, 3.8% and 12.3% of nodules showed enhancement similar to that in the aorta. In the portal venous phase, 15.4% and 21.7%, 16.8% and 18.2%, 14.1% and 23.8%, and 19.5% and 25.9% of nodules were scored with enhancement similar to that in the aorta, inferior vena cava, hepatic vein, and portal vein by readers 1 and 2, respectively. Differences between attenuation of nodules and all vessels in the arterial, portal venous, and delayed phases were statistically significant. Statistically significant differences were also noted between attenuation among blood vessels in the arterial and portal venous phases but not in the delayed phase. CONCLUSION: Attenuation of enhancing foci within hemangiomas does not match vessel density qualitatively or quantitatively. No common blood pool density exists in the arterial or portal venous phase. Although persistent enhancement without washout is a useful CT criterion, specific criteria to match the blood pool cannot be used to confirm a diagnosis of hemangioma.


Assuntos
Hemangioma/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
AJR Am J Roentgenol ; 194(2): 370-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20093598

RESUMO

OBJECTIVE: The objective of our study was to assess the clinical utility of MR-directed ("second-look") ultrasound examination to search for breast lesions detected initially on MRI. MATERIALS AND METHODS: A retrospective review was performed of the records of 158 consecutive patients (202 lesions) with breast abnormalities initially detected on MRI between July 2003 and May 2006. All lesions were detected as enhancing findings on a dynamic contrast MR study and were subsequently evaluated with ultrasound. Ultrasound was performed using MR images as a guide to lesion location, size, and morphology. Pathology findings were confirmed by subsequent percutaneous biopsy or lesion excision. Imaging follow-up was used for probably benign lesions, which were not biopsied. RESULTS: Of the 202 MRI-detected lesions, ultrasound correlation was made in 115 (57%) including 33 malignant lesions and 82 benign lesions. The remaining 87 lesions were not sonographically correlated and included 11 malignant lesions and 76 nonmalignant lesions. Mass lesions identified on MRI were more likely to have a sonographic correlate than nonmasslike lesions (65% vs 12%, respectively); malignant mass lesions were more likely to show an ultrasound correlation (85%). The malignant lesions with successful sonographic correlation tended to present with subtle sonographic findings. CONCLUSION: MR-directed ultrasound of MRI-detected lesions was useful for decision making as part of the diagnostic workup. Malignant lesions were likely to have an ultrasound correlate, especially when they presented as masses on MRI. However, the sonographic findings of these lesions were often subtle, and careful scanning technique was needed for successful MRI-ultrasound correlation.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética/métodos , Ultrassonografia Mamária/métodos , Adulto , Idoso , Biópsia , Neoplasias da Mama/patologia , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Interpretação de Imagem Assistida por Computador , Achados Incidentais , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
19.
Acad Radiol ; 16(5): 597-603, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19282206

RESUMO

RATIONALE AND OBJECTIVES: The aims of this study were to determine the feasibility of diffusion-weighted magnetic resonance imaging (DWI) in the detection of bowel inflammation and to investigate the changes in apparent diffusion coefficient (ADC) values in the inflamed bowel in patients with Crohn's disease. MATERIALS AND METHODS: Eleven patients who underwent magnetic resonance enterography (including DWI) for Crohn's disease and colonoscopy or surgery within 4 weeks of examination were recruited. Two radiologists reviewed diffusion-weighted images and ADC maps to evaluate for inflammation in each bowel segment (terminal ileum, cecum, ascending colon, transverse colon, descending colon, and rectosigmoid colon) and measured the ADC values of each bowel segment. Endoscopic and pathologic results were correlated with DWI findings. RESULTS: Fifty-three segments (19 with inflammation, 34 normal) were included. DWI detected inflammation in 18 of 19 segments (94.7%) and showed normal results in 28 of 34 segments (82.4%). On diffusion-weighted images, bowel segments with inflammation revealed higher signal compared to normal segments. Artifact levels were none or minimal in 10 of 11 patients (90.9%) and moderate in one patient. On quantitative analysis, ADC values of inflamed and normal bowel were measured as 0.47 - 2.60 x 10(-3) and 1.39 - 4.03 x 10(-3) mm(2)/s, respectively (P < .05). CONCLUSION: DWI with parallel imaging is a feasible technique for the detection of inflammation in patients with Crohn's disease. ADC values are decreased in inflamed bowel segments, indicating restricted diffusion.


Assuntos
Doença de Crohn/complicações , Doença de Crohn/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Enterite/complicações , Enterite/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Radiology ; 250(1): 41-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18955508

RESUMO

PURPOSE: To study the clinical usefulness of ultrasonography (US)-guided core-needle biopsy (CNB) of axillary lymph nodes and the US-depicted abnormalities that may be used to predict nodal metastases. MATERIALS AND METHODS: This retrospective study was HIPAA compliant and institutional review board approved; the requirement for informed patient consent was waived. US-guided 14-gauge CNB of abnormal axillary lymph nodes was performed in 100 of 144 patients with primary breast cancer who underwent US assessment of axillary lymph nodes. A biopsy needle with controllable action rather than a traditional throw-type needle was used. US findings were considered suspicious for metastasis if cortical thickening and/or nonhilar blood flow (NHBF) to the lymph node cortex was present. The absence of any discernible fatty hilum was also noted. RESULTS: Nodal metastases were documented at CNB in 64 (64%) of the 100 patients. All 36 patients with negative biopsy results underwent subsequent sentinel lymph node biopsy (SLNB), which yielded negative findings in 32 (89%) patients and revealed metastasis in four (11%). All 44 patients who did not undergo CNB because of negative US results subsequently underwent SLNB, which revealed lymph node metastasis in 12 (27%) patients. Cortical thickening was found in 63 (79%) of the total of 80 metastatic nodes, but only a minority (n = 26 [32%]) of the nodes had an absent fatty hilum. NHBF to the cortex was detected in 52 (65%) metastatic nodes. Both absence of a fatty hilum (metastasis detected in 26 [93%] of 28 nodes) and cortical thickening combined with NHBF (metastasis detected in 52 [81%] of 64 nodes) had a high positive predictive value. No clinically important complications were encountered with the biopsy procedures. CONCLUSION: Axillary lymph nodes with abnormal US findings can be sampled with high accuracy and without major complications by using a modified 14-gauge CNB technique.


Assuntos
Biópsia por Agulha , Neoplasias da Mama/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Ultrassonografia de Intervenção , Ultrassonografia Mamária , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal/diagnóstico por imagem , Carcinoma Ductal/patologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/patologia , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/irrigação sanguínea , Metástase Linfática/patologia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Biópsia de Linfonodo Sentinela , Ultrassonografia Doppler em Cores
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA