RESUMO
OBJECTIVE. The objective of our study was to compare an abbreviated liver MRI protocol with a standard liver MRI protocol for the posttreatment follow-up of colorectal metastases in assessing disease presence, segmental involvement, and response to chemotherapy and for surgical planning. MATERIALS AND METHODS. This retrospective single-center study reviewed consecutive chemotherapy-naïve patients with colorectal liver metastases (April 1, 2011-August 31, 2017) who underwent gadoxetate disodium-enhanced MRI on a 1.5-T unit before and 8-12 weeks after chemotherapy. Two radiologists blinded to outcomes independently reviewed images obtained using standard MRI sequences at baseline and after treatment. The standard MRI sequences were the following: axial T1-weighted, axial T2-weighted, axial DWI (b values = 0-750 s/mm2), axial multiphase contrast-enhanced T1-weighted, and axial and coronal hepatobiliary phase (HBP) T1-weighted sequences. The standard sequences obtained at baseline and the abbreviated protocol sequences (i.e., HBP gadoxetate disodium-enhanced T1-weighted and DWI sequences) obtained after treatment were reviewed. For each image set, reviewers assessed disease presence and segmental involvement; in addition, for images obtained after therapy, treatment response according to RECIST 1.1 was recorded. RESULTS. One hundred thirteen patients (73 men and 40 women; mean age, 61.6 years) were evaluated. The total number of metastases showed high agreement between the standard protocol and abbreviated protocol (intraclass correlation coefficient = 0.97). There was good agreement between the protocols for segmental involvement (weighted κ = 0.73-0.85), and the weighted kappa was 0.82 for all segments. Discrepancies in segmental involvement did not alter potential surgical planning. Categorization of RECIST 1.1 treatment response using the abbreviated protocol versus the standard protocol showed excellent agreement (weighted κ = 0.92). CONCLUSION. An abbreviated liver MRI protocol (i.e., HBP gadoxetate disodium-enhanced T1-weighted and DWI sequences) allows assessment after chemotherapy similar to a standard liver MRI protocol. Use of the abbreviated protocol can reduce imaging time without sacrificing diagnostic performance for the follow-up of colorectal liver metastases.
Assuntos
Neoplasias Colorretais/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Seguimentos , Gadolínio DTPA , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Critérios de Avaliação de Resposta em Tumores Sólidos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
OBJECTIVES: In accordance with initial guidance from the Royal College of Surgeons and Royal College of Radiologists, we evaluated the utility of CT of the chest in the exclusion of asymptomatic COVID-19 infection prior to elective cancer surgery on self-isolating patients during the pandemic. METHODS: All surgical referrals without symptoms of COVID-19 infection in April and May 2020 were included. Patient records were retrospectively reviewed. Screening included CT chest for major thoracic and abdominal surgery. CTs were reported according to British Society of Thoracic Imaging guidelines and correlated with reverse transcriptase polymerase chain reaction (RT-PCR) and surgical outcomes. RESULTS: The prevalence of RT-PCR confirmed COVID-19 infection in our screened population was 0.7% (5/681). 240 pre-operative CTs were performed. 3.8% (9/240) of CTs were reported as abnormal, only one of which was RT-PCR positive. 2% (5/240) of cases had surgery postponed based on CT results. All nine patients with CTs reported as abnormal have had surgery, all without complication. CONCLUSION: The prevalence of asymptomatic COVID-19 infection in our screened population was low. The pre-test probability of CT chest in asymptomatic, self-isolating patients is consequently low. CT can produce false positives in this setting, introducing unnecessary delay in surgery for a small proportion of cases. ADVANCES IN KNOWLEDGE: Self-isolation, clinical assessment and RT-PCR are effective at minimising COVID-19 related surgical risk. The addition of CT chest is unhelpful. Our data have particular relevance during the second wave of infection and in the recovery phase.
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Infecções Assintomáticas , COVID-19/diagnóstico por imagem , Procedimentos Cirúrgicos Eletivos , Neoplasias/cirurgia , Tomografia Computadorizada por Raios X , Adulto , Idoso , COVID-19/diagnóstico , Teste de Ácido Nucleico para COVID-19 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isolamento de Pacientes , Período Pré-Operatório , Estudos Retrospectivos , Tórax , Reino UnidoRESUMO
PURPOSE: To determine the 3-dimensional (3D) intrafractional motion of head and neck squamous cell carcinoma (HNSCC). METHODS AND MATERIALS: Dynamic contrast-enhanced magnetic resonance images from 56 patients with HNSCC in the treatment position were analyzed. Dynamic contrast-enhanced magnetic resonance imaging consisted of 3D images acquired every 2.9 seconds for 4 minutes 50 seconds. Intrafractional tumor motion was studied in the 3 minutes 43 seconds of images obtained after initial contrast enhancement. To assess tumor motion, rigid registration (translations only) was performed using a region of interest (ROI) mask around the tumor. The results were compared with bulk body motion from registration to all voxels. Motion was split into systematic motion and random motion. Correlations between the tumor site and random motion were tested. The within-subject coefficient of variation was determined from 8 patients with repeated baseline measures. Random motion was also assessed at the end of the first week (38 patients) and second week (25 patients) of radiation therapy to investigate trends of motion. RESULTS: Tumors showed irregular occasional rapid motion (eg, swallowing or coughing), periodic intermediate motion (respiration), and slower systematic drifts throughout treatment. For 95% of the patients, displacements due to systematic and random motion were <1.4 mm and <2.1 mm, respectively, 95% of the time. The motion without an ROI mask was significantly (P<.0001, Wilcoxon signed rank test) less than the motion with an ROI mask, indicating that tumors can move independently from the bony anatomy. Tumor motion was significantly (P=.005, Mann-Whitney U test) larger in the hypopharynx and larynx than in the oropharynx. The within-subject coefficient of variation for random motion was 0.33. The average random tumor motion did not increase notably during the first 2 weeks of treatment. CONCLUSIONS: The 3D intrafractional tumor motion of HNSCC is small, with systematic motion <1.4 mm and random motion <2.1 mm 95% of the time.
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Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia , Meios de Contraste , Humanos , Aumento da Imagem , Movimento (Física) , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagemRESUMO
Purpose: To evaluate intrinsic susceptibility (IS) MRI for the identification of cycling hypoxia, and the assessment of its extent and spatial distribution, in head and neck squamous cell carcinoma (HNSCC) xenografts and patients.Experimental Design: Quantitation of the transverse relaxation rate, R2*, which is sensitive to paramagnetic deoxyhemoglobin, using serial IS-MRI acquisitions, was used to monitor temporal oscillations in levels of paramagnetic deoxyhemoglobin in human CALR xenografts and patients with HNSCC at 3T. Autocovariance and power spectrum analysis of variations in R2* was performed for each imaged voxel, to assess statistical significance and frequencies of cycling changes in tumor blood oxygenation. Pathologic correlates with tumor perfusion (Hoechst 33342), hypoxia (pimonidazole), and vascular density (CD31) were sought in the xenografts, and dynamic contrast-enhanced (DCE) MRI was used to assess patient tumor vascularization. The prevalence of fluctuations within patient tumors, DCE parameters, and treatment outcome were reported.Results: Spontaneous R2* fluctuations with a median periodicity of 15 minutes were detected in both xenografts and patient tumors. Spatially, these fluctuations were predominantly associated with regions of heterogeneous perfusion and hypoxia in the CALR xenografts. In patients, R2* fluctuations spatially correlated with regions of lymph nodes with low Ktrans values, typically in the vicinity of necrotic cores.Conclusions: IS-MRI can be used to monitor variations in levels of paramagnetic deoxyhemoglobin, associated with cycling hypoxia. The presence of such fluctuations may be linked with impaired tumor vasculature, the presence of which may impact treatment outcome. Clin Cancer Res; 23(15); 4233-41. ©2017 AACR.
Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Linfonodos/diagnóstico por imagem , Imageamento por Ressonância Magnética , Neovascularização Patológica/diagnóstico por imagem , Animais , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Hipóxia Celular/genética , Linhagem Celular Tumoral , Meios de Contraste/uso terapêutico , Feminino , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Linfonodos/patologia , Masculino , Camundongos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Nitroimidazóis/administração & dosagem , Tolerância a Radiação/efeitos dos fármacos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Resultado do Tratamento , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
We describe a case of intra-abdominal fibromatosis, which occurred in a 44-year-old woman who had a previous history of gastrointestinal stromal tumor (GIST) of the sigmoid mesocolon, which was treated with imatinib and resection. A mass was detected at the site of ileocolic anastomosis of the previous small bowel resection and sigmoid colectomy, nearly 3 years later. Clinically, this was suspected to represent recurrent GIST and was excised, but histology and mutational analysis showed desmoid-type fibromatosis with a mutation in codon 41 of exon 3 of the CTNNB1 (ß-catenin) gene. The occurrence of fibromatosis at the site of excision of GIST is very rare, but its recognition is important as the treatment of the two neoplasms differs significantly. As imaging cannot reliably distinguish between these 2 entities, histological diagnosis is crucial for correct clinical management.
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Anastomose Cirúrgica/efeitos adversos , Fibroma/genética , Segunda Neoplasia Primária/etiologia , Neoplasias do Colo Sigmoide/genética , beta Catenina/genética , Adulto , Análise Mutacional de DNA , Feminino , Fibroma/patologia , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Mutação , Segunda Neoplasia Primária/patologia , Neoplasias do Colo Sigmoide/patologiaRESUMO
PURPOSE: To determine whether quantitation of T2* is sufficiently repeatable and sensitive to detect clinically relevant oxygenation levels in head and neck squamous cell carcinoma (HNSCC) at 3T. MATERIALS AND METHODS: Ten patients with newly diagnosed locally advanced HNSCC underwent two magnetic resonance imaging (MRI) scans between 24 and 168 hours apart prior to chemoradiotherapy treatment. A multiple gradient echo sequence was used to calculate T2* maps. A quadratic function was used to model the blood transverse relaxation rate as a function of blood oxygenation. A set of published coefficients measured at 3T were incorporated to account for tissue hematocrit levels and used to plot the dependence of fractional blood oxygenation (Y) on T2* values, together with the corresponding repeatability range. Repeatability of T2* using Bland-Altman analysis, and calculation of limits of agreement (LoA), was used to assess the sensitivity, defined as the minimum difference in fractional blood oxygenation that can be confidently detected. RESULTS: T2* LoA for 22 outlined tumor volumes were 13%. The T2* dependence of fractional blood oxygenation increases monotonically, resulting in increasing sensitivity of the method with increasing blood oxygenation. For fractional blood oxygenation values above 0.11, changes in T2* were sufficient to detect differences in blood oxygenation greater than 10% (Δ T2* > LoA for ΔY > 0.1). CONCLUSION: Quantitation of T2* at 3T can detect clinically relevant changes in tumor oxygenation within a wide range of blood volumes and oxygen tensions, including levels reported in HNSCC. J. Magn. Reson. Imaging 2016;44:72-80.
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Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/metabolismo , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Oxigênio/metabolismo , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
Malignant pleural mesothelioma (MPM) typically demonstrates a non-spherical growth pattern, so it is often difficult to accurately categorize change in tumour burden using size-based tumour response criteria (e.g., WHO (World Health Organisation), RECIST (Response Evaluation Criteria in Solid Tumours) and modified RECIST). Functional imaging techniques are applied to derive quantitative measurements of tumours, which reflect particular aspects of the tumour pathophysiology. By quantifying how these measurements change with treatment, it is possible to observe treatment effects. In this review, we survey the existing roles of CT and MRI for the management of MPM, including the currently applied size measurement criteria for the assessment of treatment response. New functional imaging techniques, such as positron emission tomography (PET), diffusion-weighted MRI (DWI) and dynamic contrast-enhanced MRI (DCE-MRI) that may potentially improve the assessment of treatment response will be highlighted and discussed.
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Neoplasias Pulmonares/diagnóstico , Mesotelioma/diagnóstico , Gerenciamento Clínico , Humanos , Neoplasias Pulmonares/terapia , Imageamento por Ressonância Magnética/métodos , Mesotelioma/terapia , Mesotelioma Maligno , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons/métodos , Critérios de Avaliação de Resposta em Tumores Sólidos , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Carga TumoralRESUMO
PURPOSE: To describe a methodology, based on cluster analysis, to partition multi-parametric functional imaging data into groups (or clusters) of similar functional characteristics, with the aim of characterizing functional heterogeneity within head and neck tumour volumes. To evaluate the performance of the proposed approach on a set of longitudinal MRI data, analysing the evolution of the obtained sub-sets with treatment. MATERIAL AND METHODS: The cluster analysis workflow was applied to a combination of dynamic contrast-enhanced and diffusion-weighted imaging MRI data from a cohort of squamous cell carcinoma of the head and neck patients. Cumulative distributions of voxels, containing pre and post-treatment data and including both primary tumours and lymph nodes, were partitioned into k clusters (k = 2, 3 or 4). Principal component analysis and cluster validation were employed to investigate data composition and to independently determine the optimal number of clusters. The evolution of the resulting sub-regions with induction chemotherapy treatment was assessed relative to the number of clusters. RESULTS: The clustering algorithm was able to separate clusters which significantly reduced in voxel number following induction chemotherapy from clusters with a non-significant reduction. Partitioning with the optimal number of clusters (k = 4), determined with cluster validation, produced the best separation between reducing and non-reducing clusters. CONCLUSION: The proposed methodology was able to identify tumour sub-regions with distinct functional properties, independently separating clusters which were affected differently by treatment. This work demonstrates that unsupervised cluster analysis, with no prior knowledge of the data, can be employed to provide a multi-parametric characterization of functional heterogeneity within tumour volumes.
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Neoplasias de Cabeça e Pescoço/patologia , Cabeça/patologia , Pescoço/patologia , Algoritmos , Carcinoma de Células Escamosas/patologia , Análise por Conglomerados , Imagem de Difusão por Ressonância Magnética/métodos , Humanos , Estudos Longitudinais , Linfonodos/patologia , Análise de Componente Principal/métodos , Estudos ProspectivosRESUMO
Liver-specific magnetic resonance (MR) contrast agents are increasingly used in evaluation of the liver. They are effective in detection and morphological characterization of lesions, and can be useful for evaluation of biliary tree anatomy and liver function. The typical appearances and imaging pitfalls of various tumours at MR imaging performed with these agents can be understood by the interplay of pharmacokinetics of these contrast agents and transporter expression of the tumour. This review focuses on the applications of these agents in oncological imaging.
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Carcinoma Hepatocelular/diagnóstico , Meios de Contraste , Aumento da Imagem , Neoplasias Hepáticas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Neoplasias dos Ductos Biliares/diagnóstico , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/diagnóstico , Gadolínio DTPA , Hemangioma/diagnóstico , Humanos , Neoplasias Hepáticas/secundário , Meglumina/análogos & derivados , Compostos OrganometálicosRESUMO
OBJECTIVE: The aim of this pilot study was to assess the feasibility of external surface-coil MRI as a new method of imaging the esophagus and esophageal cancer. CONCLUSION: The results for the 10 patients investigated indicate that by using a high-resolution axial T2-weighted sequence (small field of view, thin section images), MRI provides detailed imaging of the anatomic layers of the esophageal wall and tumor. Three independent radiologists found good correlation in the morphologic appearance and extent of tumor between MRI and matched histology sections. This study illustrates the potential of the technique as an alternative form of local staging for esophageal cancer.