RESUMO
OBJECTIVES: To develop an intuitive and generally applicable system for the reporting, assessment, and documentation of ADC to complement standard BI-RADS criteria. METHODS: This was a multicentric, retrospective analysis of 11 independently conducted institutional review board-approved studies from seven institutions performed between 2007 and 2019. Breast Apparent Diffusion coefficient (ADC-B) categories comprised ADC-B0 (ADC non-diagnostic), ADC-B1 (no enhancing lesion), and ADC-B2-5. The latter was defined by plotting ADC versus cumulative malignancy rates. Statistics comprised ANOVA with post hoc testing and ROC analysis. p values ≤ 0.05 were considered statistically significant. RESULTS: A total of 1625 patients (age: 55.9 years (± 13.8)) with 1736 pathologically verified breast lesions were included. The mean ADC (× 10-3 mm2/s) differed significantly between benign (1.45, SD .40) and malignant lesions (.95, SD .39), and between invasive (.92, SD .22) and in situ carcinomas (1.18, SD .30) (p < .001). The following ADC-B categories were identified: ADC-B0-ADC cannot be assessed; ADC-B1-no contrast-enhancing lesion; ADC-B2-ADC ≥ 1.9 (cumulative malignancy rate < 0.1%); ADC-B3-ADC 1.5 to < 1.9 (0.1-1.7%); ADC-B4-ADC 1.0 to < 1.5 (10-24.5%); and ADC-B5-ADC < 1.0 (> 24.5%). At the latter threshold, a positive predictive value of 95.8% (95% CI 0.94-0.97) for invasive versus non-invasive breast carcinomas was reached. CONCLUSIONS: The breast apparent diffusion coefficient system (ADC-B) provides a simple and widely applicable categorization scheme for assessment, documentation, and reporting of apparent diffusion coefficient values in contrast-enhancing breast lesions on MRI. CLINICAL RELEVANCE STATEMENT: The ADC-B system, based on diverse MRI examinations, is clinically relevant for stratifying breast cancer risk via apparent diffusion coefficient measurements, and complements BI-RADS for improved clinical decision-making and patient outcomes. KEY POINTS: ⢠The breast apparent diffusion coefficient category system (ADC-B) is a simple tool for the assessment, documentation, and reporting of ADC values in contrast-enhancing breast lesions on MRI. ⢠The categories comprise ADC-B0 for non-diagnostic examinations, ADC-B1 for examinations without an enhancing lesion, and ADC-B2-5 for enhancing lesions with an increasing malignancy rate. ⢠The breast apparent diffusion coefficient category system may be used to complement BI-RADS in clinical decision-making.
Assuntos
Neoplasias da Mama , Meios de Contraste , Humanos , Pessoa de Meia-Idade , Feminino , Estudos Retrospectivos , Diagnóstico Diferencial , Mama/diagnóstico por imagem , Mama/patologia , Imagem de Difusão por Ressonância Magnética , Imageamento por Ressonância Magnética , Neoplasias da Mama/patologia , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: White matter lesions (WML) in multiple sclerosis (MS) differ from vascular WML caused by Fabry disease (FD). However, in atypical cases the discrimination can be difficult and may vary between individual raters. The aim of this study was to evaluate interrater reliability of WML differentiation between MS and FD patients. MATERIALS AND METHODS: Brain MRI scans of 21 patients with genetically confirmed FD were compared to 21 matched patients with MS. Pseudonymized axial FLAIR sequences were assessed by 6 blinded raters and attributed to either the MS or the FD group to investigate interrater reliability. Additionally, localization of WML was compared between the two groups. RESULTS: The median age of patients was 46 years (IQR 35-58). Interrater reliability was moderate with a Fleiss' Kappa of 0.45 (95%CI 0.3-0.59). Overall, 85% of all ratings in the MS group and 75% in the FD group were correct. However, only 38% of patients with MS and 33% of patients with FD were correctly identified by all 6 raters. WML involving the corpus callosum (p < 0.001) as well as juxtacortical (p < 0.001) and infratentorial lesions (p = 0.03) were more frequently observed in MS patients. CONCLUSION: Interrater reliability regarding visual differentiation of WML in MS from vascular WML in FD on standard axial FLAIR images alone is only moderate, despite the distinctive features of lesions in each group.
Assuntos
Doença de Fabry , Esclerose Múltipla , Substância Branca , Adulto , Encéfalo/patologia , Doença de Fabry/diagnóstico por imagem , Doença de Fabry/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico por imagem , Reprodutibilidade dos Testes , Substância Branca/diagnóstico por imagem , Substância Branca/patologiaRESUMO
PURPOSE: Diffusion-weighted imaging with the calculation of an apparent diffusion coefficient (ADC) has been proposed as a quantitative biomarker on contrast-enhanced MRI (CE-MRI) of the breast. There is a need to approve a generalizable ADC cutoff. The purpose of this study was to evaluate whether a predefined ADC cutoff allows downgrading of BI-RADS 4 lesions on CE-MRI, avoiding unnecessary biopsies. EXPERIMENTAL DESIGN: This was a retrospective, multicentric, cross-sectional study. Data from five centers were pooled on the individual lesion level. Eligible patients had a BI-RADS 4 rating on CE-MRI. For each center, two breast radiologists evaluated the images. Data on lesion morphology (mass, non-mass), size, and ADC were collected. Histology was the standard of reference. A previously suggested ADC cutoff (≥1.5 × 10-3 mm2/second) was applied. A negative likelihood ratio of 0.1 or lower was considered as a rule-out criterion for breast cancer. Diagnostic performance indices were calculated by ROC analysis. RESULTS: There were 657 female patients (mean age, 42; SD, 14.1) with 696 BI-RADS 4 lesions included. Disease prevalence was 59.5% (414/696). The area under the ROC curve was 0.784. Applying the investigated ADC cutoff, sensitivity was 96.6% (400/414). The potential reduction of unnecessary biopsies was 32.6% (92/282). CONCLUSIONS: An ADC cutoff of ≥1.5 × 10-3 mm2/second allows downgrading of lesions classified as BI-RADS 4 on breast CE-MRI. One-third of unnecessary biopsies could thus be avoided.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem , Adulto , Biópsia , Neoplasias da Mama/patologia , Meios de Contraste , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
MATERIALS AND METHODS: In this multicentric study, individual patient data from 3 different centers were analyzed. Consecutive patients receiving standardized multiparametric breast magnetic resonance imaging for standard nonscreening indications were included. At each center, 2 experienced radiologists with more than 5 years of experience retrospectively interpreted the examinations in consensus and applied the KS to every histologically verified lesion. The corresponding mean ADC of each lesion was measured using a Wielema type 4 region of interest. According to established methods, the KS and ADC were combined, yielding the KS+ score. Diagnostic accuracy was evaluated by the area under the receiver operating characteristics curve (AUROC) and compared between the KS, ADC, and KS+ (DeLong test). Likewise, the potential to help avoid unnecessary biopsies was compared between the KS, ADC, and KS+ based on established high sensitivity thresholds (McNemar test). RESULTS: A total of 450 lesions in 414 patients (mean age, 51.5 years; interquartile range, 42-60.8 years) were included, with 219 lesions being malignant (48.7%; 95% confidence interval [CI], 44%-53.4%). The performance of the KS (AUROC, 0.915; CI, 0.886-0.939) was significantly better than that of the ADC (AUROC, 0.848; CI, 0.811-0.880; P < 0.001). The largest difference between these parameters was observed when assessing subcentimeter lesions (AUROC, 0.909 for KS; CI, 0.849-0.950 vs 0.811 for ADC; CI, 0.737-0.871; P = 0.02).The use of the KS+ (AUROC, 0.918; CI, 0.889-0.942) improved the performance slightly, but without any significant difference relative to a single KS or ADC reading (P = 0.64).When applying high sensitivity thresholds for avoiding unnecessary biopsies, the KS and ADC achieved equal sensitivity (97.7% for both; cutoff values, >4 for KS and ≤1.4 × 10-3 mm2/s for ADC). However, the rate of potentially avoidable biopsies was higher when using the KS (specificity: 65.4% for KS vs 32.9% for ADC; P < 0.0001). The KS was superior to the KS+ in avoiding unnecessary biopsies. CONCLUSIONS: Both the KS and ADC may be used to distinguish benign from malignant breast lesions. However, KS proved superior in this task including, most of all, when assessing small lesions less than 1 cm. Using the KS may avoid twice as many unnecessary biopsies, and the combination of both the KS and ADS does not improve diagnostic performance.
Assuntos
Neoplasias da Mama , Imagem de Difusão por Ressonância Magnética , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Diffusion-weighted imaging (DWI) is an MRI technique with the potential to serve as an unenhanced breast cancer detection tool. Synthetic b-values produce images with high diffusion weighting to suppress residual background signal, while avoiding additional measurement times and reducing artifacts. PURPOSE: To compare acquired DWI images (at b = 850 s/mm2 ) and different synthetic b-values (at b = 1000-2000 s/mm2 ) in terms of lesion visibility, image quality, and tumor-to-tissue contrast in patients with malignant breast tumors. STUDY TYPE: Retrospective. POPULATION: Fifty-three females with malignant breast lesions. FIELD STRENGTH/SEQUENCE: T2 w, DWI EPI with STIR fat-suppression, and dynamic contrast-enhanced T1 w at 3T. ASSESSMENT: From acquired images using b-values of 50 and 850 s/mm2 , synthetic images were calculated at b = 1000, 1200, 1400, 1600, 1800, and 2000 s/mm2 . Four readers independently rated image quality, lesion visibility, preferred b-value, as well as the lowest and highest b-value, over the range of b-values tested, to provide a diagnostic image. STATISTICAL TESTS: Medians and mean ranks were calculated and compared using the Friedman test and Wilcoxon signed-rank test. Reproducibility was analyzed by intraclass correlation (ICC), Fleiss, and Cohen's κ. RESULTS: Relative signal-to-noise and contrast-to-noise ratios decreased with increasing b-values, while the signal-intensity ratio between tumor and tissue increased significantly (P < 0.001). Intermediate b-values (1200-1800 s/mm2 ) were rated best concerning image quality and lesion visibility; the preferred b-value mostly lay at 1200-1600 s/mm2 . Lowest and highest acceptable b-values were 850 s/mm2 and 2000 s/mm2 . Interreader agreement was moderate to high concerning image quality (ICC: 0.50-0.67) and lesion visibility (0.70-0.93), but poor concerning preferred and acceptable b-values (κ = 0.032-0.446). DATA CONCLUSION: Synthetically increased b-values may be a way to improve tumor-to-tissue contrast, lesion visibility, and image quality of breast DWI, while avoiding the disadvantages of performing DWI at very high b-values. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1754-1761.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Mama/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Razão Sinal-RuídoRESUMO
BACKGROUND: Multiparametric positron emission tomography/magnetic resonance imaging (mpPET/MRI) shows clinical potential for detection and classification of breast lesions. Yet, the contribution of features for computer-aided segmentation and diagnosis (CAD) need to be better understood. We proposed a data-driven machine learning approach for a CAD system combining dynamic contrast-enhanced (DCE)-MRI, diffusion-weighted imaging (DWI), and 18F-fluorodeoxyglucose (18F-FDG)-PET. METHODS: The CAD incorporated a random forest (RF) classifier combined with mpPET/MRI intensity-based features for lesion segmentation and shape features, kinetic and spatio-temporal texture features, for lesion classification. The CAD pipeline detected and segmented suspicious regions and classified lesions as benign or malignant. The inherent feature selection method of RF and alternatively the minimum-redundancy-maximum-relevance feature ranking method were used. RESULTS: In 34 patients, we report a detection rate of 10/12 (83.3%) and 22/22 (100%) for benign and malignant lesions, respectively, a Dice similarity coefficient of 0.665 for segmentation, and a classification performance with an area under the curve at receiver operating characteristics analysis of 0.978, a sensitivity of 0.946, and a specificity of 0.936. Segmentation but not classification performance of DCE-MRI improved with information from DWI and FDG-PET. Feature ranking revealed that kinetic and spatio-temporal texture features had the highest contribution for lesion classification. 18F-FDG-PET and morphologic features were less predictive. CONCLUSION: Our CAD enables the assessment of the relevance of mpPET/MRI features on segmentation and classification accuracy. It may aid as a novel computational tool for exploring different modalities/features and their contributions for the detection and classification of breast lesions.
Assuntos
Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Meios de Contraste , Imagem de Difusão por Ressonância Magnética , Fluordesoxiglucose F18 , Imageamento por Ressonância Magnética Multiparamétrica , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Adulto , Idoso , Doenças Mamárias/classificação , Doenças Mamárias/patologia , Neoplasias da Mama/classificação , Neoplasias da Mama/patologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Aprendizado de Máquina , Pessoa de Meia-Idade , Imagem Multimodal , Estudos Retrospectivos , Adulto JovemRESUMO
BACKGROUND: Due to often overlapping imaging features, solid renal tumors pose a diagnostic challenge. In addition, personalized therapies require exact tumor subtyping. To reduce complications, this should ideally be performed noninvasively. AIMS: The aim of this work was to provide an overview on the current state of the art and new developments in the field of noninvasive radiological phenotyping of the most common types of adult renal tumors. RESULTS: Multimodal and multiparametric imaging already enables an exact, noninvasive differentiation between many types of benign and malignant renal tumors. Concerning problematic cases, as well as for a more detailed characterization of renal tumors (tumor grade, genetic factors), promising new techniques, or techniques that have not previously been used for this purpose, such as texture analysis, computer-based "deep feature classifications", iodine quantification or MR spectroscopy, are being investigated.
Assuntos
Neoplasias Renais , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Adulto , Humanos , Neoplasias Renais/diagnóstico por imagem , Imagem Multimodal , RadiografiaRESUMO
OBJECTIVE: The aim of this study was to evaluate the potential of diffusion-weighted imaging-derived apparent diffusion coefficient (ADC) measurements to obviate unnecessary biopsies in multiparametric MRI-detected PI-RADS 4 and 5 lesions. MATERIALS AND METHODS: This retrospective, institutional review board-approved study investigated 101 PI-RADS 4 and 5 prostate lesions (52 malignant, 49 benign) verified by in-bore MRI-guided biopsy in 101 men (mean age, 62.8 years). Two readers, who were not aware of the biopsy results independently and repeatedly measured minimum, mean, and maximum ADC from diffusion-weighted imaging measurements (in line with PI-RADS v2 recommendations) using a 2-dimensional region of interest drawn around the biopsied lesions. Diagnostic performance was evaluated using receiver operating characteristic statistics and reproducibility statistics were calculated. RESULTS: The best diagnostic performance (overall area under the receiver operating characteristic curve [AUC] R1: 0.801; R2: 0.796 peripheral zone AUC R1:0.814, R2: 0.805; transitional zone AUC R1:0.786, R2:0.779) and the tightest limits of interreader agreement (-8.6% to 9.9%) were found in minimum ADC values. Rule-in and rule-out thresholds for diagnosis of prostate cancer were identified, demonstrating a potential to avoid unnecessary biopsies in 32.7% (16/49). CONCLUSIONS: Quantitative ADC measurement in multiparametric MRI-detected PI-RADS 4 and 5 lesions has the potential to avoid unnecessary MRI-guided biopsies in up to 33%.
Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Sistemas de Informação em Radiologia , Procedimentos Desnecessários , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Humanos , Aumento da Imagem/métodos , Biópsia Guiada por Imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Próstata/diagnóstico por imagem , Próstata/patologia , Curva ROC , Radiologia Intervencionista , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
OBJECTIVES: The aim of this study was to assess the potential of noncontrast magnetic resonance imaging (NC-MRI) with diffusion-weighted imaging (DWI) in characterization of breast lesions in comparison to dynamic contrast-enhanced MRI (DCE-MRI) at 3 T. MATERIALS AND METHODS: Consecutive patients with conventional imaging (mammography, ultrasound) BI-RADS 4/5 findings were included in this institutional review board-approved single-center study. All underwent 3 T breast MRI including readout-segmented DWI, DCE, and T2-weighted sequences. Final diagnosis was defined by histopathology or follow-up (>24 months). Two experienced radiologists (R1, R2) independently assigned lesion conspicuity (0 = minimal to 3 = excellent) and BI-RADS scores to NC-MRI (readout-segmented DWI including apparent diffusion coefficient maps) and DCE-MRI (DCE and T2-weighted). Receiver operating characteristics, κ statistics, and visual grading characteristics analysis were applied. RESULTS: Sixty-seven malignant and 56 benign lesions were identified in 113 patients (mean age, 54 ± 14 years). Areas under the receiver operating characteristics curves were similar: DCE-MRI: 0.901 (R1), 0.905 (R2); NC-MRI: 0.882 (R1), 0.854 (R2); P > 0.05, respectively. The κ agreement was 0.968 (DCE-MRI) and 0.893 (NC-MRI). Visual grading characteristics analysis revealed superior lesion conspicuity by DCE-MRI (0.661, P < 0.001). CONCLUSIONS: Diagnostic performance and interreader agreement of both NC-MRI and DCE-MRI is high, indicating a potential use of NC-MRI as an alternative to DCE-MRI. However, inferior lesion conspicuity and lower interreader agreement of NC-MRI need to be considered.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Meios de Contraste , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
PURPOSE: To investigate prevalence, malignancy rates, imaging features, and follow-up intervals for probably benign (BI-RADS 3) lesions on breast magnetic resonance imaging (MRI). METHODS: A systematic database-review of articles published through 22/06/2016 was performed. Eligible studies reported BI-RADS 3 lesions on breast MRI. Two independent reviewers performed a literature review and data extraction. Data collection included study characteristics, number/type of BI-RADS 3 lesions, final diagnosis (histopathology and/or follow-up). Sources of bias (QUADAS-2) were assessed. Meta-analysis included data-pooling, heterogeneity testing, and meta-regression. RESULTS: Fifteen studies were included. Prevalence was reported in 11 studies (range: 1.2-24.3%). Malignancy rates ranged between 0.5-10.1% (pooled 61/2814, 1.6%, 95%-CI:0.9-2.3% (random-effects-model), I2=53%, P=0.007). In a subgroup of 11 studies (2183 lesions), highest malignancy rates were observed in non-mass lesions (pooled 25/714, 2.3%, 95%-CI:0.8-3.9%, I2=52%, P=0.021) followed by mass lesions (pooled 15/771, 1.5%, 95%-CI:0.7-2.4%, I2=0%, P=0.929), and foci (pooled 10/698, 1%, 95%-CI:0.3-1.7%, I2=0%, P=0.800). There was non-significant negative association between prevalence and malignancy rates (P=0.077). Malignant lesions were diagnosed at all follow-up time points. CONCLUSION: While prevalence of MRI BI-RADS 3 lesions was strongly heterogeneous, pooled malignancy rates met BI-RADS benchmarks (<2%). Malignancy rates varied, exceeding 2% in non-mass lesions. Twenty-four-month surveillance is required to detect all malignant lesions. KEY POINTS: ⢠Probably benign (BI-RADS 3) lesions showed a pooled malignancy-rate of 1.6% (95%-CI:0.9-2.3%). ⢠Malignancy rates differ and are highest in non-mass lesions (2.3%, 95%-CI:0.8-3.9%). ⢠The prevalence of BI-RADS 3 lesions on breast MRI ranged from 1.2-24.3%. ⢠Malignant lesions were diagnosed at follow-up time points up to 24 months.
Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética/métodos , Neoplasias da Mama/epidemiologia , Diagnóstico Diferencial , Feminino , Saúde Global , Humanos , PrevalênciaRESUMO
OBJECTIVES: To determine whether 3D acquisitions provide equivalent image quality, lesion delineation quality and PI-RADS v2 performance compared to 2D acquisitions in T2-weighted imaging of the prostate at 3 T. METHODS: This IRB-approved, prospective study included 150 consecutive patients (mean age 63.7 years, 35-84 years; mean PSA 7.2 ng/ml, 0.4-31.1 ng/ml). Two uroradiologists (R1, R2) independently rated image quality and lesion delineation quality using a five-point ordinal scale and assigned a PI-RADS score for 2D and 3D T2-weighted image data sets. Data were compared using visual grading characteristics (VGC) and receiver operating characteristics (ROC)/area under the curve (AUC) analysis. RESULTS: Image quality was similarly good to excellent for 2D T2w (mean score R1, 4.3 ± 0.81; R2, 4.7 ± 0.83) and 3D T2w (mean score R1, 4.3 ± 0.82; R2, 4.7 ± 0.69), p = 0.269. Lesion delineation was rated good to excellent for 2D (mean score R1, 4.16 ± 0.81; R2, 4.19 ± 0.92) and 3D T2w (R1, 4.19 ± 0.94; R2, 4.27 ± 0.94) without significant differences (p = 0.785). ROC analysis showed an equivalent performance for 2D (AUC 0.580-0.623) and 3D (AUC 0.576-0.629) T2w (p > 0.05, respectively). CONCLUSIONS: Three-dimensional acquisitions demonstrated equivalent image and lesion delineation quality, and PI-RADS v2 performance, compared to 2D in T2-weighted imaging of the prostate. Three-dimensional T2-weighted imaging could be used to considerably shorten prostate MRI protocols in clinical practice. KEY POINTS: ⢠3D shows equivalent image quality and lesion delineation compared to 2D T2w. ⢠3D T2w and 2D T2w image acquisition demonstrated comparable diagnostic performance. ⢠Using a single 3D T2w acquisition may shorten the protocol by 40%. ⢠Combined with short DCE, multiparametric protocols of 10 min are feasible.
Assuntos
Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Próstata/patologia , Neoplasias da Próstata/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROCRESUMO
RATIONALE AND OBJECTIVES: This study aimed to investigate the potential of contrast-enhanced magnetic resonance imaging features to differentiate between mass-forming intrahepatic cholangiocellular carcinoma (ICC) and hepatocellular carcinoma (HCC) in cirrhotic livers. MATERIALS AND METHODS: This study, performed between 2001 and 2013, included 64 baseline magnetic resonance imaging examinations with pathohistologically proven liver cirrhosis, presenting with either ICC (n = 32) or HCC (n = 32) tumors. To distinguish ICC form HCC tumors, 20 qualitative single-lesion descriptors were evaluated by two readers, in consensus, and statistically classified using the chi-square automatic interaction detection (CHAID) methodology. Diagnostic performance was assessed by a receiver operating characteristic analysis. RESULTS: The CHAID algorithm identified three independent categorical lesion descriptors, including (1) liver capsular retraction; (2) progressive or persistent enhancement pattern or wash-out on the T1-weighted delayed phase; and (3) signal intensity appearance on T2-weighted images that could help to reliably differentiate ICC from HCC, which resulted in an AUC of 0.807, and a sensitivity and specificity of 68.8 and 90.6 (95% confidence interval 75.0-98.0), respectively. CONCLUSIONS: The proposed CHAID algorithm provides a simple and robust step-by-step classification tool for a reliable and solid differentiation between ICC and HCC tumors in cirrhotic livers.
Assuntos
Neoplasias dos Ductos Biliares/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Carcinoma Hepatocelular/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Humanos , Cirrose Hepática/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
To demonstrate the accuracy of fully automated, quantitative, volumetric measurement of the amount of fibroglandular breast tissue (FGT), using MRI, and to investigate the impact of different MRI sequences using anthropomorphic breast phantoms as the ground truth. In this study, 10 anthropomorphic breast phantoms that consisted of different known fractions of adipose and protein tissue, which closely resembled normal breast parenchyma, were developed. Anthropomorphic breast phantoms were imaged with a 1.5 T unit (Siemens, Avantofit) using an 18-channel breast coil. The sequence protocol consisted of an isotropic Dixon sequence (Di), an anisotropic Dixon sequence (Da), and T1 3D FLASH sequences with and without fat saturation (T1). Fully automated, quantitative, volumetric measurement of FGT for all anthropomorphic phantoms and sequences was performed and correlated with the amounts of fatty and protein components in the phantoms as the ground truth. Fully automated, quantitative, volumetric measurements of FGT with MRI for all sequences ranged from 5.86 to 61.05% (mean 33.36%). The isotropic Dixon sequence yielded the highest accuracy (median 0.51%-0.78%) and precision (median range 0.19%) compared with anisotropic Dixon (median 1.92%-2.09%; median range 0.55%) and T1 -weighted sequences (median 2.54%-2.46%; median range 0.82%). All sequences yielded good correlation with the FGT content of the anthropomorphic phantoms. The best correlation of FGT measurements was identified for Dixon sequences (Di, R2 = 0.999; Da, R2 = 0.998) compared with conventional T1 -weighted sequences (R2 = 0.971). MRI yields accurate, fully automated, quantitative, volumetric measurements of FGT, an increasingly important and sensitive imaging biomarker for breast cancer risk. Compared with conventional T1 sequences, Dixon-type sequences show the highest correlation and reproducibility for automated, quantitative, volumetric FGT measurements using anthropomorphic breast phantoms as the ground truth.
Assuntos
Mama/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Automação , Feminino , HumanosRESUMO
OBJECTIVES: To investigate the influence of region-of-interest (ROI) placement and different apparent diffusion coefficient (ADC) parameters on ADC values, diagnostic performance, reproducibility and measurement time in breast tumours. METHODS: In this IRB-approved, retrospective study, 149 histopathologically proven breast tumours (109 malignant, 40 benign) in 147 women (mean age 53.2) were investigated. Three radiologists independently measured minimum, mean and maximum ADC, each using three ROI placement approaches:1 - small 2D-ROI, 2 - large 2D-ROI and 3 - 3D-ROI covering the whole lesion. One reader performed all measurements twice. Median ADC values, diagnostic performance, reproducibility, and measurement time were calculated and compared between all combinations of ROI placement approaches and ADC parameters. RESULTS: Median ADC values differed significantly between the ROI placement approaches (p < .001). Minimum ADC showed the best diagnostic performance (AUC .928-.956), followed by mean ADC obtained from 2D ROIs (.926-.94). Minimum and mean ADC showed high intra- (ICC .85-.94) and inter-reader reproducibility (ICC .74-.94). Median measurement time was significantly shorter for the 2D ROIs (p < .001). CONCLUSIONS: ROI placement significantly influences ADC values measured in breast tumours. Minimum and mean ADC acquired from 2D-ROIs are useful for the differentiation of benign and malignant breast lesions, and are highly reproducible, with rapid measurement. KEY POINTS: ⢠Region of interest placement significantly influences apparent diffusion coefficient of breast tumours. ⢠Minimum and mean apparent diffusion coefficient perform best and are reproducible. ⢠2D regions of interest perform best and provide rapid measurement times.
Assuntos
Neoplasias da Mama/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Estudos Retrospectivos , Adulto JovemRESUMO
Diffusion-weighted MRI (DWI) provides insights into tissue microstructure by visualization and quantification of water diffusivity. Quantitative evaluation of the apparent diffusion coefficient (ADC) obtained from DWI has been proven helpful for differentiating between malignant and benign breast lesions, for cancer subtyping in breast cancer patients, and for prediction of response to neoadjuvant chemotherapy. However, to further establish DWI of breast lesions it is important to evaluate the quantitative imaging biomarker (QIB) characteristics of reproducibility, repeatability, and diagnostic accuracy. In this intra-individual prospective clinical study 40 consecutive patients with suspicious findings, scheduled for biopsy, underwent an identical 3T breast MRI protocol of the breast on two consecutive days (>24 h). Mean ADC of target lesions was assessed (two independent readers) in four separate sessions. Reproducibility, repeatability, and diagnostic accuracy between examinations (E1, E2), readers (R1, R2), and measurements (M1, M2) were assessed with intraclass correlation coefficients (ICCs), coefficients of variation (CVs), Bland-Altman plots, and receiver operating characteristic (ROC) analysis with calculation of the area under the ROC curve (AUC). The standard of reference was either histopathology (n = 38) or imaging follow-up of up to 24 months (n = 2). Eighty breast MRI examinations (median E1-E2, 2 ± 1.7 days, 95% confidence interval (CI) 1-2 days, range 1-11 days) in 40 patients (mean age 56, standard deviation (SD) ±14) were evaluated. In 55 target lesions (mean size 25.2 ± 20.8 (SD) mm, range 6-106 mm), mean ADC values were significantly (P < 0.0001) higher in benign (1.38, 95% CI 1.27-1.49 × 10(-3) mm(2) /s) compared with malignant (0.86, 95% CI 0.81-0.91 × 10(-) (3) mm(2) /s) lesions. Reproducibility and repeatability showed high agreement for repeated examinations, readers, and measurements (all ICCs >0.9, CVs 3.2-8%), indicating little variation. Bland-Altman plots demonstrated no systematic differences, and diagnostic accuracy was not significantly different in the two repeated examinations (all ROC curves >0.91, P > 0.05). High reproducibility, repeatability, and diagnostic accuracy of DWI provide reliable characteristics for its use as a potential QIB, to further improve breast lesion detection, characterization, and treatment monitoring of breast lesions.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Feminino , Humanos , Aumento da Imagem/métodos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto JovemRESUMO
PURPOSE: To compare the reproducibility and diagnostic performance of PI-RADS version 2 (v2) and version 1 (v1) for the diagnosis of prostate cancer (PCa) on multiparametric MRI. METHODS: This IRB-approved retrospective study included 65 consecutive biopsy-naïve or biopsy-negative patients suspicious for PCa (mean age: 65 years, mean PSA: 10.8ng/ml) who were undergoing MR-guided biopsy after multiparametric 3T prostate MRI (T2w, DWI, DCE). Two independent readers (R1; R2) scored the prostate lesions according to the v2 score and the v1 sum score. Diagnostic measures (sensitivity, specificity, and area under the ROC-curve) were compared for all cases and stratified by location (transitional zone, TZ, peripheral zone, PZ). Inter-reader agreement was assessed by kappa statistics. RESULTS: Inter reader agreement for v2 and v1 was substantial to almost perfect (kappa v2: 0.71, v1: 0.81). Overall, sensitivity between both readers and methods did not differ (p>0.05). Overall specificity was higher using v1 compared to v2 (R1: p=0.0078, R2: p=0.0313) In the TZ, v2 showed a higher AUC (0.81-0.84) compared to v1 (AUC 0.77-0.78). Here, the sensitivity of v2 (87.5-100%) was higher than that of v1 (75%) while v2 specificity (50%-56.3%) was lower than that of v1 (68.8-75%). In the PZ, AUCs were higher using v1 (AUC 0.82-0.83) compared to v2 (AUC 0.61-0.63). The specificity for v1 was higher (43.8-62.3%) than that for v2 (12.5-18.8%) while both v2 and v1 achieved 100% sensitivity. CONCLUSION: PI-RADS v2 and v1 inter-reader agreement is excellent, but their diagnostic performance differs. While v2 appears to be the preferable method for the evaluation of TZ lesions, v1 performs better in the PZ.
Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Sistemas de Informação em Radiologia/normas , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Biópsia/métodos , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/patologia , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
PURPOSE: The purpose of this study was to compare three different biopsy devices on false-negative and underestimation rates in MR-guided, vacuum-assisted breast biopsy (VABB) of MRI-only lesions. METHODS: This retrospective, single-center study was IRB-approved. Informed consent was waived. 467 consecutive patients underwent 487 MR-guided VABB using three different 8-10-gauge-VABB devices (Atec-9-gauge,A; Mammotome-8-gauge,M; Vacora-10-gauge,V). VABB data (lesion-type, size, biopsy device, histopathology) were compared to final diagnosis (surgery, n = 210 and follow-up, n = 277). Chi-square, and Kruskal-Wallis tests were applied. P values < 0.05 were considered significant. RESULTS: Final diagnosis was malignant in 104 (21.4 %), high risk in 64 (13.1 %) and benign in 319 (65.5 %) cases. Eleven of 328 (3.4 %) benign-rated lesions were false-negative (1/95, 1.1 %, A; 2/73, 2.7 %, M; 8/160 5.0 % V; P = 0.095). Eleven high-risk (11/77, 14.3 %) lesions proved to be malignant (3/26, 11.5 % A; 4/12, 33.3 % M; 4/39, 10.3 % V; P = 0.228). Five of 34 (14.7 %) DCIS were upgraded to invasive cancer (2/15, 13.3 %, A; 1/6, 16.6 % M; 2/13, 15.3 %, V; P = 0.977). Lesion size (P = 0.05) and type (mass vs. non-mass, P = 0.107) did not differ significantly. CONCLUSION: MR-guided VABB is an accurate method for diagnosis of MRI-only lesions. No significant differences on false-negative and underestimation rates were observed between three different biopsy devices. KEY POINTS: ⢠MR-guided VABB is an accurate procedure for the diagnosis of MRI-only lesions. ⢠Similar false-negative and underestimation rates allow all three different MR-guided VABB devices for clinical application. ⢠High-risk lesions should undergo surgery due to a substantial underestimation rate. ⢠Agreement between MR-guided VABB and final diagnosis (benign/malignant) was 95.5% (465/487).
Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Carcinoma Ductal de Mama/patologia , Adulto , Idoso , Biópsia por Agulha/métodos , Feminino , Humanos , Biópsia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , VácuoRESUMO
OBJECTIVES: The objective of this study was to evaluate whether apparent diffusion coefficient (ADC) obtained through diffusion-weighted imaging magnetic resonance imaging at 3 T can be used as an imaging biomarker to differentiate invasive breast cancer from noninvasive ductal carcinoma in situ (DCIS). MATERIALS AND METHODS: One hundred seventy-six histopathologically verified primary malignant breast tumors were retrospectively evaluated in 170 patients. All patients had undergone a standardized 3-T magnetic resonance imaging protocol, containing a diffusion-weighted sequence with 2 b values and a series of dynamic contrast-enhanced T1-weighted sequences. Apparent diffusion coefficient was measured manually by a reader blinded to the histopathological results. The ADC values were correlated with histopathological results. Mean ADC values were compared between invasive cancers and DCIS as well as between different tumor grades. Receiver operating characteristics curves were used to calculate diagnostic performance. RESULTS: There were 155 invasive cancers and 21 noninvasive DCIS. Mean (SD) values differed significantly between the invasive cancers (0.9 [0.15] ×10 mm/s) and the DCIS (1.24 [0.23] ×10 mm/s, P < 0.001). Area under the receiver operating characteristics curve was 0.895 (95% confidence interval [CI], 0.840-0.936). A threshold of 1.01 ×10 mm/s or less allowed an identification of invasive cancers with a sensitivity of 78.06% (95% CI, 70.7%-84.3%) and a specificity of 90.5% (95% CI, 69.6%-98.8%). No significant ADC differences were found among different tumor grades (P > 0.05). CONCLUSIONS: Apparent diffusion coefficient could be used as an imaging biomarker for the diagnosis of breast cancer. It seems to be a valuable noninvasive quantitative biomarker to assess breast cancer invasiveness. Thus, ADC measurements provide the potential to reduce overdiagnosis and subsequent overtreatment.
Assuntos
Algoritmos , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Diagnóstico Diferencial , Feminino , Humanos , Aumento da Imagem/métodos , Pessoa de Meia-Idade , Invasividade Neoplásica , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
PURPOSE: To assess whether multiparametric (18)fluorodeoxyglucose positron emission tomography magnetic resonance imaging (MRI) (MP (18)FDG PET-MRI) using dynamic contrast-enhanced MRI (DCE-MRI), diffusion-weighted imaging (DWI), three-dimensional proton MR spectroscopic imaging (3D (1)H-MRSI), and (18)FDG-PET enables an improved differentiation of benign and malignant breast tumors. EXPERIMENTAL DESIGN: Seventy-six female patients (mean age, 55.7 years; range, 25-86 years) with an imaging abnormality (BI-RADS 0, 4-5) were included in this Institutional Review Board (IRB)-approved study. Patients underwent fused PET-MRI of the breast with (18)FDG-PET/CT and MP MRI at 3T. The likelihood of malignancy was assessed for all single parameters, for MP MRI with two/three parameters, and for MP (18)FDG PET-MRI. Histopathology was used as the standard of reference. Appropriate statistical tests were used to assess sensitivity, specificity, and diagnostic accuracy for each assessment combination. RESULTS: There were 53 malignant and 23 benign breast lesions. MP (18)FDG PET-MRI yielded a significantly higher area under the cure (AUC) of 0.935 than DCE-MRI (AUC, 0.86; P = 0.044) and the combination of DCE-MRI and another parameter (AUC, 0.761-0.826; P = 0.013-0.020). MP (18)FDG PET-MRI showed slight further improvement to MP MRI with three parameters (AUC, 0.925; P = 0.317). Using MP (18)FDG PET-MRI there would have been a reduction of the unnecessary breast biopsies recommended by MP imaging with one or two parameters (P = 0.002-0.011). CONCLUSION: This feasibility study shows that MP (18)FDG PET-MRI enables an improved differentiation of benign and malignant breast tumors when several MRI and PET parameters are combined. MP (18)FDG PET-MRI may lead to a reduction in unnecessary breast biopsies.
Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Fluordesoxiglucose F18 , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carga TumoralRESUMO
Recently, molecular imaging, using various techniques, has been assessed for breast imaging. Molecular imaging aims to quantify and visualize biological, physiological, and pathological processes at the cellular and molecular levels to further elucidate the development and progression of breast cancer and the response to treatment. Molecular imaging enables the depiction of tumor morphology, as well as the assessment of functional and metabolic processes involved in cancer development at different levels. To date, molecular imaging techniques comprise both nuclear medicine and radiological techniques. This review aims to summarize the current and emerging functional and metabolic techniques for the molecular imaging of breast tumors.