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Hepatocellular carcinoma (HCC) is the sixth most common neoplasia and the third leading cause of cancer-associated deaths worldwide. Most cases arise in patients with cirrhosis, and early detection through periodic screening can make it potentially curable. The presence of extrahepatic metastases (EHM) affects treatment decisions and curability. The lungs are the most common site for EHM, followed by lymph nodes, bones, and the adrenal glands. Interestingly, approximately only 15 cases of HCC metastasizing to the pituitary gland have been reported so far.The most common symptoms of pituitary metastasis (PM) arising from HCC are nerve palsies affecting the third, fourth, and sixth cranial nerves. Other symptoms, such as diabetes insipidus or pituitary insufficiencies, are present in a minority of cases. Detecting PM is difficult given its rarity. Gold-standard treatments for these patients have not yet been established, but the prognosis is dismal, with a median overall survival of only 4.5 months. In this paper, we present an interesting case of PM as the first symptom of an HCC in a 75-year-old female. We also present an overview of all cases reported to date with emphasis on symptom presentation and survival after diagnosis.Given the improvement of systemic therapy, more cases are diagnosed in both oligometastatic and palliative conditions. Therefore, better approaches and treatment modalities for extrahepatic metastases due to HCC should be defined.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Neoplasias Hipofisárias , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Carcinoma Hepatocelular/secundário , Carcinoma Hepatocelular/patologia , Feminino , Idoso , Neoplasias Hipofisárias/secundário , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/terapia , Neoplasias Hipofisárias/diagnóstico , Diagnóstico Diferencial , Resultado do TratamentoRESUMO
BACKGROUND: Stereotactic body radiotherapy (SBRT) is an effective therapeutic approach in patients with liver metastases. However, long-term changes in hepatic normal tissue have to be taken into account in multimodal treatment regimes. Magnetic-resonance-imaging (MRI) based morphologic liver alterations (MMA) after liver SBRT have been analyzed longitudinally. MATERIAL AND METHODS: 57 patients treated with gantry-based or robotic-based SBRT of 69 treatment volumes of liver metastases, who had long-term follow-up (FU) ≥6 months were included in this retrospective analysis. Post-SBRT MMAs were contoured on each contrast-enhanced-T1-weighted (T1w) MRI-sequence. Morphologic/volumetric data of the liver and MMAs were evaluated longitudinally, including the dependency on treatment-related factors of the planning target volume (PTV) and liver. RESULTS: The median FU time was 1 year [6-48 months]. 66 of 69 treatment volumes developed MMAs (mean 143.8 ± 135.1 ccm at first appearance). 31.8% of MMAs resolved completely during FU. Of the persisting MMAs 82.2%/13.3% decreased/increased in size until last available FU. Morphological characterization of the MMAs at first appearance included 75% hypointense and 25% hyperintense T1w-MRI-based appearances. Hypointense as compared to hyperintense appearance was significantly associated with a higher mean liver dose EQD2α/ß=3 Gy (p = 0.0212) and non-significantly greater MMA size. Variance analysis demonstrated a significant reduction of MMA and total liver volume after SBRT (p < 0.0001). The volume reduction decelerated longitudinally for both MMA (p < 0.0001) and liver size (p = 0.0033). Radiation doses (PTV-BEDα/ß=3 Gy and 10 Gy) were not significantly associated with MMA volume reduction. SBRT of liver metastases with mean liver dose EQD2α/ß=3 Gy > 18 Gy were characterized by greater MMA volumes (p = 0.0826) and steeper MMA reduction gradients during FU than those with EQD2α/ß=3 Gy ≤ 18 Gy (p < 0.0001). CONCLUSION: Radiogenic MMAs either completely resolve or usually decrease in volume with pronounced reduction during short-term FU. This course was independent of the MMA's morphological appearance. Further, increased mean liver dose was associated with greater MMA size and a greater gradient of MMA size reduction during FU.
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Neoplasias Hepáticas , Radiocirurgia , Humanos , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Estudos Retrospectivos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética , Dosagem RadioterapêuticaRESUMO
Current research, especially in oncology, increasingly focuses on the integration of quantitative, multiparametric and functional imaging data. In this fast-growing field of research, radiomics may allow for a more sophisticated analysis of imaging data, far beyond the qualitative evaluation of visible tissue changes. Through use of quantitative imaging data, more tailored and tumour-specific diagnostic work-up and individualized treatment concepts may be applied for oncologic patients in the future. This is of special importance in cross-sectional disciplines such as radiology and radiation oncology, with already high and still further increasing use of imaging data in daily clinical practice. Liver targets are generally treated with stereotactic body radiotherapy (SBRT), allowing for local dose escalation while preserving surrounding normal tissue. With the introduction of online target surveillance with implanted markers, 3D-ultrasound on conventional linacs and hybrid magnetic resonance imaging (MRI)-linear accelerators, individualized adaptive radiotherapy is heading towards realization. The use of big data such as radiomics and the integration of artificial intelligence techniques have the potential to further improve image-based treatment planning and structured follow-up, with outcome/toxicity prediction and immediate detection of (oligo)progression. The scope of current research in this innovative field is to identify and critically discuss possible application forms of radiomics, which is why this review tries to summarize current knowledge about interdisciplinary integration of radiomics in oncologic patients, with a focus on investigations of radiotherapy in patients with liver cancer or oligometastases including multiparametric, quantitative data into (radio)-oncologic workflow from disease diagnosis, treatment planning, delivery and patient follow-up.
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Biologia Computacional , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Radioterapia (Especialidade)/métodos , Assistência ao Convalescente , Quimioembolização Terapêutica , Terapia Combinada , Aprendizado Profundo , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Órgãos em Risco , Prognóstico , Radiocirurgia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem , Cirurgia Assistida por ComputadorRESUMO
Oncologic imaging focused on the detection of breast cancer is of increasing importance, with over 1.7 million new cases detected each year worldwide. MRI of the breast has been described to be one of the most sensitive imaging modalities in breast cancer detection; however, clinical use is limited due to high costs. In the past, the objective and clinical routine of oncologic imaging was to provide one extended imaging protocol covering all potential needs and clinical implications regardless of the specific clinical indication or question. Future protocols might be more focused according to a "keep it short and simple" approach, with a reduction of patient magnet time and a limited number of images to review. Rather than replacing conventional full-diagnostic breast MRI protocols, these approaches aim at introducing a new thinking in oncologic imaging using a diversification of available imaging approaches targeted to the dedicated clinical needs of the individual patient. Here we review current approaches on using abbreviated protocols that aim to increase the clinical availability and use of breast MRI for improved early detection of breast cancer. Level of Evidence: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:647-658.
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Neoplasias da Mama/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Mama/diagnóstico por imagem , Meios de Contraste/farmacologia , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imagem Multimodal/métodosRESUMO
BACKGROUND: Chemical exchange saturation transfer (CEST) is a novel MRI technique applied to brain tumor patients. PURPOSE: To investigate the anatomic location dependence of CEST MRI obtained at 7T and histopathological/molecular parameters in WHO IV° glioma patients. STUDY TYPE: Analytic prospective study. POPULATION: Twenty-one patients with newly diagnosed WHO IV° gliomas were studied prior to surgery; 11 healthy volunteers were investigated. FIELD STRENGTH/SEQUENCE: Conventional MRI (contrast-enhanced, T2 w and diffusion-weighted imaging) at 3T and T2 w and CEST MRI at 7T was performed for patients and both patients and volunteers. ASSESSMENT: Mean CEST signal intensities (nuclear-Overhauser-enhancement [NOE], amide-proton-transfer [APT], downfield NOE-suppressed APT [dns-APT]), ADC values, and histopathological/molecular parameters were evaluated with regard to hemisphere location and contact with the subventricular zone. CEST signal intensities of cerebral tissue of healthy volunteers were evaluated with regard to hemisphere discrimination. STATISTICAL TESTS: Spearman correlation, Mann-Whitney U-test, Wilcoxon signed-rank-test, Fisher's exact test, and area under the receiver operating curve. RESULTS: Maximum APT and dns-APT signal intensities were significantly different in right vs. left hemisphere gliomas (P = 0.037 and P = 0.007), but not in right vs. left hemisphere cerebral tissue of healthy subjects (P = 0.062-0.859). Mean ADC values were significantly decreased in right vs. left hemisphere gliomas (P = 0.044). Mean NOE signal intensity did not differ significantly between gliomas of either hemisphere (P = 0.820), but in case of subventricular zone contact (P = 0.047). A significant correlation was observed between APT and dns-APT and ADC signal intensities (rs = -0.627, P = 0.004 and rs = -0.534, P = 0.019), but not between NOE and ADC (rs = -0.341, P = 0.154). Histopathological/molecular parameters were not significantly different concerning the tumor location (P = 0.104-1.000, P = 0.286-0.696). DATA CONCLUSION: APT, dns-APT, and ADC were inversely correlated and depended on the gliomas' hemisphere location. NOE showed significant dependence on subventricular zone contact. Location dependency of APT- and NOE-mediated CEST effects should be considered in clinical investigations of CEST MRI. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;49:777-785.
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Neoplasias Encefálicas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Glioblastoma/diagnóstico por imagem , Gliossarcoma/diagnóstico por imagem , Adulto , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto JovemRESUMO
OBJECTIVES: The purpose of this study was to investigate the association of relaxation-compensated chemical exchange saturation transfer (CEST) MRI with overall survival (OS) and progression-free survival (PFS) in newly diagnosed high-grade glioma (HGG) patients. METHODS: Twenty-six patients with newly diagnosed high-grade glioma (WHO grades III-IV) were included in this prospective IRB-approved study. CEST MRI was performed on a 7.0-T whole-body scanner. Association of patient OS/PFS with relaxation-compensated CEST MRI (amide proton transfer (APT), relayed nuclear Overhauser effect (rNOE)/NOE, downfield-rNOE-suppressed APT (dns-APT)) and diffusion-weighted imaging (apparent diffusion coefficient) were assessed using the univariate Cox proportional hazards regression model. Hazard ratios (HRs) and corresponding 95% confidence intervals were calculated. Furthermore, OS/PFS association with clinical parameters (age, gender, O6-methylguanine-DNA methyltransferase (MGMT) promotor methylation status, and therapy: biopsy + radio-chemotherapy vs. debulking surgery + radio-chemotherapy) were tested accordingly. RESULTS: Relaxation-compensated APT MRI was significantly correlated with patient OS (HR = 3.15, p = 0.02) and PFS (HR = 1.83, p = 0.009). The strongest association with PFS was found for the dns-APT metric (HR = 2.61, p = 0.002). These results still stand for the relaxation-compensated APT contrasts in a homogenous subcohort of n = 22 glioblastoma patients with isocitrate dehydrogenase (IDH) wild-type status. Among the tested clinical parameters, patient age (HR = 1.1, p = 0.001) and therapy (HR = 3.68, p = 0.026) were significant for OS; age additionally for PFS (HR = 1.04, p = 0.048). CONCLUSION: Relaxation-compensated APT MRI signal intensity is associated with overall survival and progression-free survival in newly diagnosed, previously untreated glioma patients and may, therefore, help to customize treatment and response monitoring in the future. KEY POINTS: ⢠Amide proton transfer (APT) MRI signal intensity is associated with overall survival and progression in glioma patients. ⢠Relaxation compensation enhances the information value of APT MRI in tumors. ⢠Chemical exchange saturation transfer (CEST) MRI may serve as a non-invasive biomarker to predict prognosis and customize treatment.
Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Glioma/diagnóstico por imagem , Adulto , Idoso , Amidas , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologia , Progressão da Doença , Feminino , Glioblastoma/diagnóstico por imagem , Glioblastoma/enzimologia , Glioblastoma/patologia , Glioma/enzimologia , Glioma/patologia , Humanos , Isocitrato Desidrogenase/metabolismo , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Intervalo Livre de Progressão , Estudos Prospectivos , PrótonsRESUMO
BACKGROUND: The present work aimed to analyze the feasibility of a shuttle-based MRI-guided radiation therapy (MRgRT) in the treatment of pelvic malignancies. PATIENTS AND METHODS: 20 patients with pelvic malignancies were included in this prospective feasibility analysis. Patients underwent daily MRI in treatment position prior to radiotherapy at the German Cancer Research Center. Positional inaccuracies, time and patient compliance were assessed for the application of off-line MRgRT. RESULTS: In 78% of applied radiation fractions, MR imaging for position verification could be performed without problems. Additionally, treatment-related side effects and reduced patient compliance were only responsible for omission of MRI in 9% of radiation fractions. The study workflow took a median time of 61â¯min (range 47-99â¯min); duration for radiotherapy alone was 13â¯min (range 7-26â¯min). Patient positioning, MR imaging and CT imaging including patient repositioning and the shuttle transfer required median times of 10â¯min (range 7-14â¯min), 26â¯min (range 15-60â¯min), 5â¯min (range 3-8â¯min) and 8â¯min (range 2-36â¯min), respectively. To assess feasibility of shuttle-based MRgRT, the reference point coordinates for the x, y and z axis were determined for the MR images and CT obtained prior to the first treatment fraction and correlated with the coordinates of the planning CT. In our dataset, the median positional difference between MR imaging and CT-based imaging based on fiducial matching between MR and CT imaging was equal to or less than 2â¯mm in all spatial directions. The limited space in the MR scanner influenced patient selection, as the bore of the scanner had to accommodate the immobilization device and the constructed stereotactic frame. Therefore, obese, extremely muscular or very tall patients could not be included in this trial in addition to patients for whom exposure to MRI was generally judged inappropriate. CONCLUSION: This trial demonstrated for the first time the feasibility and patient compliance of a shuttle-based off-line approach to MRgRT of pelvic malignancies.
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Imageamento por Ressonância Magnética/métodos , Neoplasias Pélvicas/radioterapia , Radioterapia Guiada por Imagem/métodos , Adulto , Idoso , Tomografia Computadorizada de Feixe Cônico , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Avaliação de Processos e Resultados em Cuidados de Saúde , Posicionamento do Paciente , Neoplasias Pélvicas/diagnóstico por imagem , Neoplasias Pélvicas/patologia , Estudos ProspectivosRESUMO
Purpose The time course of changes of the liver function after stereotactic body radiotherapy (SBRT) was analyzed in patients treated for non-resectable hepatocellular carcinoma (HCC). Patients and methods Twenty-six patients with non-resectable HCC treated with SBRT were included in this study. Clinical, biochemical and treatment-related parameters were retrospectively collected. S-albumin, s-bilirubin, s-alkaline phosphatase (AP) and s-alanine transaminase (ALAT) at 0, 3, 6, and 12 months after radiotherapy were analyzed. Results Seventeen and nine patients were Child-Pugh class A and B, respectively. The liver was exposed to relatively high radiation doses with mean doses of 1.9-26 Gy. None of the patients developed classic radiotherapy-induced liver disease (RILD), but two patients developed non-classic RILD. Two patients developed grade 3 ascites and no grade 4-5 toxicities were observed. Six patients declined in Child-Pugh class. The s-albumin decreased significantly from a pretreatment median of 37.4-34.36 g/l at three months after SBRT and stabilized thereafter. S-bilirubin, s-AP and s-ALAT did not change significantly over the study period. Conclusion Despite the fact that patients received high radiation dose to the liver, there was only moderate morbidity related to the treatment. The s-albumin decreases over three months after SBRT reflecting minor to moderate hepatic toxicity. S-albumin should be observed in the follow-up of HCC patients treated with SBRT.
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Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Fígado/metabolismo , Radiocirurgia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Bilirrubina/sangue , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Fígado/efeitos da radiação , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Testes de Função Hepática , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Radiocirurgia/métodos , Albumina Sérica/metabolismoRESUMO
BACKGROUND: Treatment options for patients with locally advanced pancreatic cancer include surgery, chemotherapy as well as radiotherapy. In many cases, surgical resection is not possible, and therefore treatment alternatives have to be performed. Chemoradiation has been established as a convincing treatment alternative for locally advanced pancreatic cancer. Carbon ions offer physical and biological characteristics. Due to their inverted dose profile and the high local dose deposition within the Bragg peak precise dose application and sparing of normal tissue is possible. Moreover, in comparison to photons, carbon ions offer an increased relative biological effectiveness (RBE), which can be calculated between 1.16 and 2.46 depending on the pancreatic cancer cell line as well as the endpoint analyzed. Japanese Data on the evaluation of carbon ion radiation therapy showed promising results for patients with pancreatic cancer. METHODS AND DESIGN: The present PHOENIX-01 trial evaluates carbon ion radiotherapy using the active rasterscanning technique in patients with advanced pancreatic cancer in combination with weekly gemcitabine and adjuvant gemcitabine. Primary endpoint is toxicity, secondary endpoints are overall survival, progression-free survival and response. DISCUSSION: The physical and biological properties of the carbon ion beam promise to improve the therapeutic ratio in patients with pancreatic cancer: Due to the inverted dose profile dose deposition in the entry channel of the beam leads to sparing of normal tissue; the Bragg peak can be directed into the defined target volume, and the sharp dose fall-off thereafter again spares normal tissue behind the target volume. The higher RBE of carbon ions, which has been shown also for pancreatic cancer cell lines in the preclinical setting, is likely to contribute to an increase in local control, and perhaps in OS. Early data from Japanese centers have shown promising results. In conclusion, this is the first trial to evaluate actively delivered carbon ion beams in patients with locally advanced pancreatic cancer within a dose-escalation strategy. TRIAL REGISTRATION: NCT01795274.
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Protocolos Clínicos , Radioterapia com Íons Pesados , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/radioterapia , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/uso terapêutico , Quimiorradioterapia Adjuvante , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Radioterapia com Íons Pesados/efeitos adversos , Humanos , Estadiamento de Neoplasias , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/mortalidade , Doses de Radiação , Resultado do Tratamento , GencitabinaRESUMO
PURPOSE: To compare image quality of an optimized diffusion weighted imaging (DWI) sequence with advanced post-processing and motion correction (advanced-EPI) to a standard DWI protocol (standard-EPI) in pancreatic imaging. MATERIALS AND METHODS: 62 consecutive patients underwent abdominal MRI at 1.5 T were included in this retrospective analysis of data collected as part of an IRB approved study. All patients received a standard-EPI and an advanced-EPI DWI with advanced post-processing and motion correction. Two blinded radiologists evaluated the parameters image quality, detail of parenchyma, sharpness of boundaries and discernibility from adjacent structures on b = 900 s/mm2 images using a Likert-like scale. Segmentation of pancreatic head, body and tail were obtained and apparent diffusion coefficient (ADC) was calculated separately for each region. Apparent tissue-to-background ratio (TBR) was calculated at b = 50 s/mm2 and at b = 900 s/mm2. RESULTS: The advanced-EPI yielded significantly higher scores for pancreatic parameters of image quality, detail level of parenchyma, sharpness of boundaries and discernibility from adjacent structures in comparison to standard-EPI (p < 0.001 for all, kappa = [0.46,0.71]) and was preferred in 96% of the cases when directly compared. ADC of the pancreas was 7% lower in advanced-EPI (1.236 ± 0.152 vs. 1.146 ± 0.126 µm2/ms, p < 0.001). ADC in the pancreatic tail was significantly lower for both sequences compared to head and body (all p < 0.001). There was comparable TBR for both sequences at b = 50 s/mm2 (standard-EPI: 19.0 ± 5.9 vs. advanced-EPI: 19.0 ± 6.4, p = 0.96), whereas at b = 900 s/mm2, TBR was 51% higher for advanced-EPI (standard-EPI: 7.1 ± 2.5 vs. advanced-EPI: 10.8 ± 5.1, p < 0.001). CONCLUSION: An advanced DWI sequence might increase image quality for focused imaging of the pancreas and providing improved parenchymal detail levels compared to a standard DWI.
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Artefatos , Imagem Ecoplanar , Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar/métodos , Humanos , Pâncreas/diagnóstico por imagem , Reprodutibilidade dos Testes , Estudos RetrospectivosRESUMO
BACKGROUND: Local treatment of metastases in combination with systemic therapy can prolong survival of oligo-metastasized patients. To fully exploit this potential, safe and effective treatments are needed to ensure long-term metastases control. Stereotactic body radiotherapy (SBRT) is one means, however, for moving liver tumors correct delivery of high doses is challenging. After validating equal in-vivo treatment accuracy, we analyzed a pooled multi-platform liver-SBRT-database for clinical outcome. METHODS: Local control (LC), progression-free interval (PFI), overall survival (OS), predictive factors and toxicity was evaluated in 135 patients with 227 metastases treated by gantry-based SBRT (deep-inspiratory breath-hold-gating; n = 71) and robotic-based SBRT (fiducial-tracking, n = 156) with mean gross tumor volume biological effective dose (GTV-BEDα/ß=10Gy) of 146.6 Gy10. RESULTS: One-, and five-year LC was 90% and 68.7%, respectively. On multivariate analysis, LC was significantly predicted by colorectal histology (p = 0.006). Median OS was 20 months with one- and two-year OS of 67% and 37%. On multivariate analysis, ECOG-status (p = 0.003), simultaneous chemotherapy (p = 0.003), time from metastasis detection to SBRT-treatment (≥2months; p = 0.021) and LC of the treated metastases (≥12 months, p < 0.009) were significant predictors for OS. One- and two-year PFI were 30.5% and 14%. Acute toxicity was mild and rare (14.4% grade I, 2.3% grade II, 0.6% grade III). Chronic °III/IV toxicities occurred in 1.1%. CONCLUSIONS: Patient selection, time to treatment and sufficient doses are essential to achieve optimal outcome for SBRT with active motion compensation. Local control appears favorable compared to historical control. Long-term LC of the treated lesions was associated with longer overall survival.
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Radiocirurgia , Seguimentos , Humanos , Fígado , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
INTRODUCTION: Magnetic resonance imaging (MRI) of the abdomen increasingly incorporates diffusion-weighted imaging (DWI) sequences. Whereas DWI can substantially aid in detecting and characterizing suspicious findings, it remains unclear to what extent the use of ultra-high b-value DWI might further be of aid for the radiologist especially when using DWI sequences with advanced processing. The target of this study was therefore to compare high and ultra-high b-value DWI in abdominal MRI examinations. METHODS: This institutional review board-approved, prospective study included abdominal MRI examinations of 70 oncologic patients (mean age, 58 years; range, 21-90 years) examined with a clinical 1.5 T MRI scanner (MAGNETOM Aera, Siemens Healthcare, Erlangen, Germany) with an advanced echo planar DWI sequence (b = 0, 50, 900, and 1500 s/mm) after ex vivo phantom and in vivo volunteer investigations. High b900 and ultra-high b1500 DWIs were compared by a qualitative reading for image quality and lesion conspicuity using a 5-point Likert scale with 2 radiologists as readers. The ratios of apparent signal intensities of suspicious lesions/normal tissue of the same organ (LNTRs) were calculated. Appropriate methods were used for statistical analysis, including Wilcoxon signed-rank test and κ statistic for interreader agreement analysis (P < 0.05/0.0125/0.005 after Bonferroni correction). RESULTS: Image quality was significantly increased with b900 as compared with b1500 DWI (P < 0.001) despite using an advanced DWI sequence. A total of 153 suspicious lesions were analyzed. Overall reader confidence for characterization/detection of malignant lesions and, correspondingly, the LNTR (mean, 2.7 ± 1.8 vs 2.4 ± 1.6) were significantly higher with b900 than with b1500 DWI (P < 0.001 and P < 0.001). The increased confidence of lesion recognition and LNTR in the b900 DWI remained significant qualitatively in lymphatic and hepatic lesions and quantitatively in lymphatic, pulmonal, and osseous lesions. CONCLUSIONS: Using high b-value DWI (900 s/mm) provided an improved image quality and also lesion conspicuity as compared with ultra-high b-value DWI (1500 s/mm) in oncologic abdominal examinations despite using advanced processing. Consequently, the value for additional ultra-high b-value DWI in oncologic examinations should be critically evaluated in future studies.
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Abdome/diagnóstico por imagem , Neoplasias Abdominais/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto JovemRESUMO
INTRODUCTION: Diffusion-weighted imaging (DWI) is an important part of oncological magnetic resonance imaging (MRI) examinations, especially for tertiary cancer prevention in terms of early detection of recurrent disease. However, abdominal studies can be challenged by motion artifacts, poor signal-to-noise ratios, and visibility of retroperitoneal structures, which necessitates sequence optimization depending on the investigated region. This study aims at prospectively evaluating an adapted DWI sequence ex vivo and in vivo in oncologic patients undergoing abdominal MRI. METHODS: This institutional review board-approved, prospective study included phantom measurements, volunteer examinations, and oncologic patient examinations of the abdomen. Fifty-seven MRI examinations in 54 patients (mean age, 58 years; range, 21-90 years) were included into the analysis. The MRI examination were performed at a 1.5 T MRI scanner (MAGNETOM Aera; Siemens Healthcare, Erlangen, Germany) and included both a standard EPI-DWI (s-DWI; b = 50, 900 s/mm) and an adapted DWI (opt-DWI; EPI-DWI with b = 0, 50, 900, 1500 s/mm, acquisition with higher spatial resolution and optimized processing for the abdomen including motion correction, adaptive image combination, and background suppression). For b = 900 s/mm, the ratio of signal intensity in the normal tissue and the standard deviation of the noise in the surrounding air was quantitatively calculated; image quality and tissue differentiation parameters were rated by 2 independent, blinded readers using a 5-point Likert scale. Statistics included Wilcoxon signed-rank test and kappa statistic (P < 0.05/0.0125 after Bonferroni correction). RESULTS: The DWI phantom demonstrated an optimized contour sharpness and inlay differentiation for opt-DWI. The apparent ratio of normal tissue signal/standard deviation of background noise at b = 900 s/mm of the right/left hemiabdomen was significantly increased in opt-DWI (mean, 71.9 ± 23.5/86.0 ± 43.3) versus s-DWI (mean, 51.4 ± 15.4/63.4 ± 36.5; P < 0.001). Image quality parameters (contour sharpness and tissue differentiation of upper abdominal and retroperitoneal structures) were significantly increased in opt-DWI versus s-DWI (P < 0.001). Interreader reliability test showed good agreement (kappa = 0.768; P < 0.001). DISCUSSION: This study prospectively evaluated the potential of adapted DWI for screening in tertiary prevention of oncologic patients. An optimized DWI protocol with advanced processing achieved improved image quality in quantitative and qualitative analyses. Oncological optimization of DWI should be performed before its application in cancer patients to improve both screening and follow-up examinations, to better unleash the diagnostic potential of DWI.
Assuntos
Neoplasias Abdominais/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Prevenção Terciária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Imagens de Fantasmas , Estudos Prospectivos , Reprodutibilidade dos Testes , Razão Sinal-Ruído , Adulto JovemRESUMO
PURPOSE/OBJECTIVE(S): Along with breast-conserving surgery (BCS), adjuvant radiotherapy (RT) of patients with early breast cancer plays a crucial role in the oncologic treatment concept. Conventionally, irradiation is carried out with the aid of tangentially arranged fields. However, more modern and more complex radiation techniques such as IMRT (intensity-modulated radio therapy) are used more frequently, as they improve dose conformity and homogeneity and, in some cases, achieve better protection of adjacent risk factors. The use of this technique has implications for the incidental- and thus unintended- irradiation of adjacent loco regional lymph drainage in axillary lymph node levels I-III and internal mammary lymph nodes (IMLNs). A comparison of a homogeneous "real-life" patient collective, treated with helical tomotherapy (TT), patients treated with 3D conformal RT conventional tangentially arranged fields (3DCRT) and deep inspiration breath hold (3DCRT-DIBH), was conducted. MATERIALS/METHODS: This study included 90 treatment plans after BCS, irradiated in our clinic from January 2012 to August 2016 with TT (n = 30) and 3D-CRT (n = 30), 3DCRT DIBH (n = 30). PTVs were contoured at different time points by different radiation oncologists (> 7). TT was performed with a total dose of 50.4 Gy and a single dose of 1.8 Gy with a simultaneous integrated boost (SIB) to the tumor cavity (TT group). Patients irradiated with 3DCRT/3DCRT DIBH received 50 Gy à 2 Gy and a sequential boost. Contouring of lymph drainage routes was performed retrospectively according to RTOG guidelines. RESULTS: Average doses (DMean) in axillary lymph node Level I/Level II/Level III were 31.6 Gy/8.43 Gy/2.38 Gy for TT, 24.0 Gy/11.2 Gy/3.97 Gy for 3DCRT and 24.7 Gy/13.3 Gy/5.59 Gy for 3DCRT-DIBH patients. Internal mammary lymph nodes (IMLNs) Dmean were 27.8 Gy (TT), 13.5 Gy (3DCRT), and 18.7 Gy (3DCRT-DIBH). Comparing TT to 3DCRT-DIBH dose varied significantly in all axillary lymph node levels and the IMLNs. Comparing TT to 3DCRT significant dose difference in Level I and IMLNs was observed. CONCLUSION: Dose applied to locoregional lymph drainage pathways varies comparing tomotherapy plans to conventional tangentially arranged fields. Studies are warranted whether dose variations influence loco-regional spread and must have implications for target volume definition guidelines.
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Neoplasias da Mama/radioterapia , Linfonodos/efeitos da radiação , Órgãos em Risco/efeitos da radiação , Lesões por Radiação/prevenção & controle , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Adjuvante/normas , Radioterapia Conformacional/normas , Suspensão da Respiração , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Dosagem Radioterapêutica , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada , Estudos RetrospectivosRESUMO
BACKGROUND: The purpose of this study is to evaluate the tumor movement and accuracy of patient immobilization in stereotactic body radiotherapy of liver tumors with low pressure foil or abdominal compression. METHODS: Fifty-four liver tumors treated with stereotactic body radiotherapy were included in this study. Forty patients were immobilized by a vacuum couch with low pressure foil, 14 patients by abdominal compression. We evaluated the ratio of gross tumor volume/internal target volume, the tumor movement in 4D-computed tomography scans and daily online adjustments after cone beam computed tomography scans. RESULTS: The ratio of gross tumor volume/internal target volume was smaller with low pressure foil. The tumor movement in 4D-computed tomography scans was smaller with abdominal compression, the cranial movement even significantly different (p = 0.02). The mean online adjustments and their mean absolute values in the vertical, lateral and longitudinal axis were smaller with abdominal compression. The online adjustments were significantly different (p < 0.013), their absolute values in case of the longitudinal axis (p = 0.043). There was no significant difference of the adjustments' 3D vectors. CONCLUSIONS: In comparison to low pressure foil, abdominal compression leads to a reduction of the tumor movement. Online adjustments decreased significantly, thus leading to higher accuracy in patient positioning.
Assuntos
Imobilização/instrumentação , Neoplasias Hepáticas/radioterapia , Radiocirurgia/instrumentação , Radioterapia Guiada por Imagem/instrumentação , Humanos , Movimento , Posicionamento do Paciente , Reprodutibilidade dos TestesRESUMO
Background: Early identification of prognostic superior characteristics in glioma patients such as isocitrate dehydrogenase (IDH) mutation and O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation status is of great clinical importance. The study purpose was to investigate the non-invasive predictability of IDH mutation status, MGMT promoter methylation, and differentiation of low-grade versus high-grade glioma (LGG vs HGG) in newly diagnosed patients employing relaxation-compensated multipool chemical exchange saturation transfer (CEST) MRI at 7.0 Tesla. Methods: Thirty-one patients with newly diagnosed glioma were included in this prospective study. CEST MRI was performed at a 7T whole-body scanner. Nuclear Overhauser effect (NOE) and isolated amide proton transfer (APT; downfield NOE-suppressed APT = dns-APT) CEST signals (mean value and 90th signal percentile) were quantitatively investigated in the whole tumor area with regard to predictability of IDH mutation, MGMT promoter methylation status, and differentiation of LGG versus HGG. Statistics were performed using receiver operating characteristic (ROC) and area under the curve (AUC) analysis. Results were compared with advanced MRI methods (apparent diffusion coefficient and relative cerebral blood volume ROC/AUC analysis) obtained at 3T. Results: dns-APT CEST yielded highest AUCs in IDH mutation status prediction (dns-APTmean = 91.84%, P < 0.01; dns-APT90 = 97.96%, P < 0.001). Furthermore, dns-APT metrics enabled significant differentiation of LGG versus HGG (AUC: dns-APTmean = 0.78, P < 0.05; dns-APT90 = 0.83, P < 0.05). There was no significant difference regarding MGMT promoter methylation status at any contrast (P > 0.05). Conclusions: Relaxation-compensated multipool CEST MRI, particularly dns-APT imaging, enabled prediction of IDH mutation status and differentiation of LGG versus HGG and should therefore be considered as a non-invasive MR biomarker in the diagnostic workup.
Assuntos
Neoplasias Encefálicas/genética , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Imagem de Difusão por Ressonância Magnética/métodos , Glioma/genética , Isocitrato Desidrogenase/genética , Mutação , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Feminino , Seguimentos , Glioma/diagnóstico por imagem , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROCRESUMO
PURPOSE: To prospectively investigate chemical exchange saturation transfer (CEST) MRI in glioblastoma patients as predictor of early tumor progression after first-line treatment. EXPERIMENTAL DESIGN: Twenty previously untreated glioblastoma patients underwent CEST MRI employing a 7T whole-body scanner. Nuclear Overhauser effect (NOE) as well as amide proton transfer (APT) CEST signals were isolated using Lorentzian difference (LD) analysis and relaxation compensated by the apparent exchange-dependent relaxation rate (AREX) evaluation. Additionally, NOE-weighted asymmetric magnetic transfer ratio (MTRasym) and downfield-NOE-suppressed APT (dns-APT) were calculated. Patient response to consecutive treatment was determined according to the RANO criteria. Mean signal intensities of each contrast in the whole tumor area were compared between early-progressive and stable disease. RESULTS: Pre-treatment tumor signal intensity differed significantly regarding responsiveness to first-line therapy in NOE-LD (p = 0.0001), NOE-weighted MTRasym (p = 0.0186) and dns-APT (p = 0.0328) contrasts. Hence, significant prediction of early progression was possible employing NOE-LD (AUC = 0.98, p = 0.0005), NOE-weighted MTRasym (AUC = 0.83, p = 0.0166) and dns-APT (AUC = 0.80, p = 0.0318). The NOE-LD provided the highest sensitivity (91%) and specificity (100%). CONCLUSIONS: CEST derived contrasts, particularly NOE-weighted imaging and dns-APT, yielded significant predictors of early progression after fist-line therapy in glioblastoma. Therefore, CEST MRI might be considered as non-invasive tool for customization of treatment in the future.
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Particle therapy is characterized by distinct physical properties leading to a reduction of integral dose compared to photons. While protons have an almost comparable biological effect, carbon ions and other heavier charged particles offer an increased relative biological effectiveness. The potential clinical benefit has been pointed out by several groups. Most likely, for protons, children have the largest margin of benefit since their normal tissue is very sensitive to radiation, and curative treatments lead to extremely long-term survivors having a lot of scope for long-term side effects. Many clinical studies, mostly of a retrospective nature, have shown promising results for various tumor types being treated with proton and heavy ion radiotherapy. Further clinical trials are needed in order to evaluate the opportunities of ion beam therapy and its prognostic influence on the general outcome, and many studies are currently recruiting patients. The aim here is to summarize current knowledge, possible clinical rationales, and indications for ion beam therapy.
RESUMO
Pancreatic cancer, especially in case of locally advanced stage has a poor prognosis. Radiotherapy in general can lead to tumor volume reduction, but further improvements, such as ion beam therapy have to be promoted in order to enable dose escalation, which in turn results in better local control rates and downsizing of the tumor itself. Ion beam therapy with its highly promising physical properties is also accompanied by distinct inter- and intrafractional challenges in case of robustness. First clinical results are promising, but further research in motion mitigation and biological treatment planning is necessary, in order to determine the best clinical rationales and conditions of ion beam therapy of pancreatic cancer. This review summarizes the current knowledge and studies on ion beam therapy of pancreatic cancer.
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Radioterapia com Íons Pesados , Neoplasias Pancreáticas/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Eficiência Biológica Relativa , Humanos , Neoplasias Pancreáticas/patologia , Dosagem Radioterapêutica , Resultado do Tratamento , Carga TumoralRESUMO
BACKGROUND: The aim of the thesis is to improve treatment plans of carbon ion irradiation by integrating the tissues' specific [Formula: see text]-values for patients with locally advanced pancreatic cancer (LAPC). MATERIAL AND METHODS: Five patients with LAPC were included in this study. By the use of the treatment planning system Syngo RT Planning (Siemens, Erlangen, Germany) treatment plans with carbon ion beams have been created. Dose calculation was based on [Formula: see text]-values for both organs at risk (OAR) and the tumor. Twenty-five treatment plans and thirty-five forward calculations were created. With reference to the anatomy five field configurations were included. Single Beam Optimization (SBO) and Intensity Modulated Particle Therapy (IMPT) were used for optimization. The plans were analyzed with respect to both dose distributions and individual anatomy. The plans were evaluated using a customized index. RESULTS: With regard to the target, a field setup with one single posterior field achieves the highest score in our index. Field setups made up of three fields achieve good results in OAR sparing. Nevertheless, the field setup with one field is superior in complex topographic conditions. But, allocating an [Formula: see text]-value of 2 Gy to the spinal cord leads to critical high maximum doses in the spinal cord. The evaluation of dose profiles showed significant dose peaks at borders of the [Formula: see text]-gradient, especially in case of a single posterior field. CONCLUSION: Optimization with specific [Formula: see text]-values allows a more accurate view on dose distribution than previously. A field setup with one single posterior field achieves good results in case of difficult topographic conditions, but leads to high maximum doses to the spinal cord. So, field setups with multiple fields seem to be more adequate in case of LAPC, being surrounded by highly radiosensitive normal tissues.