Pancreatic neuroendocrine neoplasms(panNEN)are a heterogeneous group of tumors with differing pathological,genetic,and clinical features.Based on clinical findings,they may be categorized into functioning and nonfunct...Pancreatic neuroendocrine neoplasms(panNEN)are a heterogeneous group of tumors with differing pathological,genetic,and clinical features.Based on clinical findings,they may be categorized into functioning and nonfunctioning tumors.Adoption of the 2017 World Health Organization classification system,particularly its differentiation between grade 3,well-differentiated pancreatic neuroendocrine tumors(panNET)and grade 3,poorly-differentiated pancreatic neuroendocrine carcinomas(panNEC)has emphasized the role imaging plays in characterizing these lesions.Endoscopic ultrasound can help obtain biopsy specimen and assess tumor margins and local spread.Enhancement patterns on computed tomography(CT)and magnetic resonance imaging(MRI)may be used to classify panNEN.Contrast enhanced MRI and diffusion-weighted imaging have been reported to be useful for characterization of panNEN and quantifying metastatic burden.Current and emerging radiotracers have broadened the utility of functional imaging in evaluating panNEN.Fluorine-18 fluorodeoxyglucose positron emission tomography(PET)/CT and somatostatin receptor imaging such as Gallium-681,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid–octreotate PET/CT may be useful for improved identification of panNEN in comparison to anatomic modalities.These new techniques can also play a direct role in optimizing the selection of treatment for individuals and predicting tumor response based on somatostatin receptor expression.In addition,emerging methods of radiomics such as texture analysis may be a potential tool for staging and outcome prediction in panNEN,however further investigation is required before clinical implementation.展开更多
BACKGROUND The management of rectal cancer patients is mainly based on the use of the magnetic resonance imaging(MRI)technique as a diagnostic tool for both staging and restaging.After treatment,to date,the evaluation...BACKGROUND The management of rectal cancer patients is mainly based on the use of the magnetic resonance imaging(MRI)technique as a diagnostic tool for both staging and restaging.After treatment,to date,the evaluation of complete response is based on the histopathology assessment by using different tumor regression grade(TRG)features(e.g.,Dworak or Mandard classifications).While from the radiological point of view,the main attention for the prediction of a complete response after chemotherapy treatment focuses on MRI and the potential role of diffusion-weighted images and perfusion imaging represented by dynamiccontrast enhanced MRI.The main aim is to find a reliable tool to predict tumor response in comparison to histopathologic findings.AIM To investigate the value of dynamic contrast-enhanced perfusion-MRI parameters in the evaluation of the healthy rectal wall and tumor response to chemo-radiation therapy in patients with local advanced rectal cancer with histopathologic correlation.METHODS Twenty-eight patients with biopsy-proven rectal adenocarcinoma who underwent a dynamic contrast-enhanced MR study performed on a 1.5 T MRI system(Achieva,Philips),before(MR1)and after chemoradiation therapy(MR2),were enrolled in this study.The protocol included T1 gadolinium enhanced THRIVE sequences acquired on axial planes.A dedicated workstation was used to generate color permeability maps.Region of interest was manually drawn on tumor tissue and normal rectal wall,hence the following parameters were calculated and statistically analyzed:Relative arterial enhancement(RAE),relative venous enhancement(RVE),relative late enhancement(RLE),maximum enhancement(ME),time to peak and area under the curve(AUC).Perfusion parameters were related to pathologic TRG(Mandard’s criteria;TRG1=complete regression,TRG5=no regression).RESULTS Ten tumors(36%)showed complete or subtotal regression(TRG1-2)at histology and classified as responders;18 tumors(64%)were classified as non-responders(TRG3-5).Perfusion MRI parameters were significantly higher in the tumor tissue than in the healthy tissue in MR1(P<0.05).At baseline(MR1),no significant difference in perfusion parameters was found between responders and nonresponders.After chemo-radiation therapy,at MR2,responders showed significantly(P<0.05)lower perfusion values[RAE(%)54±20;RVE(%)73±24;RLE(%):82±29;ME(%):904±429]compared to non-responders[RAE(%):129±45;RVE(%):154±39;RLE(%):164±35;ME(%):1714±427].Moreover,in responders group perfusion values decreased significantly at MR2[RAE(%):54±20;RVE(%):73±24;RLE(%):82±29;ME(%):904±429]compared to the corresponding perfusion values at MR1[RAE(%):115±21;RVE(%):119±21;RLE(%):111±74;ME(%):1060±325];(P<0.05).Concerning the time-intensity curves,the AUC at MR2 showed significant difference(P=0.03)between responders and non-responders[AUC(mm2×10-3)121±50 vs 258±86],with lower AUC values of the tumor tissue in responders compared to nonresponders.In non-responders,there were no significant differences between perfusion values at MR1 and MR2.CONCLUSION Dynamic contrast perfusion-MRI analysis represents a complementary diagnostic tool for identifying vascularity characteristics of tumor tissue in local advanced rectal cancer,useful in the assessment of treatment response.展开更多
Early detection of skeletal metastasis is critical for accurate staging and optimal treatment. This paper briefly reviews our current understanding of the biological mechanisms through which tumours metastasise to bon...Early detection of skeletal metastasis is critical for accurate staging and optimal treatment. This paper briefly reviews our current understanding of the biological mechanisms through which tumours metastasise to bone and describes the available imaging methods to diagnose bone metastasis and monitor response to treatment. Among the various imaging modalities currently available for imaging skeletal metastasis, hybrid techniques whichfuse morphological and functional data are the most sensitive and specific, and positron emission tomography(PET)/computed tomography and PET/magnetic resonance imaging will almost certainly continue to evolve and become increasingly important in this regard.展开更多
患者女,56岁,因“双侧甲状腺乳头状癌”接受“甲状腺全切术+颈部淋巴结清扫术”后1月余;检出糖尿病3个月。查体:颈前见横向手术瘢痕,余未见明显异常。实验室检查:促甲状腺素(thyroid stimulating hormone,TSH)92.72μIU/ml,血清刺激性...患者女,56岁,因“双侧甲状腺乳头状癌”接受“甲状腺全切术+颈部淋巴结清扫术”后1月余;检出糖尿病3个月。查体:颈前见横向手术瘢痕,余未见明显异常。实验室检查:促甲状腺素(thyroid stimulating hormone,TSH)92.72μIU/ml,血清刺激性甲状腺球蛋白(thyroglobulin,Tg)>479ng/ml。行^(131)I清除残余甲状腺组织(简称清甲)治疗后全身显像(^(131)I post therapy whole body scan,Rx-WBS)见颈部多发淋巴结及双肺多发结节^(131)I浓聚。展开更多
文摘Pancreatic neuroendocrine neoplasms(panNEN)are a heterogeneous group of tumors with differing pathological,genetic,and clinical features.Based on clinical findings,they may be categorized into functioning and nonfunctioning tumors.Adoption of the 2017 World Health Organization classification system,particularly its differentiation between grade 3,well-differentiated pancreatic neuroendocrine tumors(panNET)and grade 3,poorly-differentiated pancreatic neuroendocrine carcinomas(panNEC)has emphasized the role imaging plays in characterizing these lesions.Endoscopic ultrasound can help obtain biopsy specimen and assess tumor margins and local spread.Enhancement patterns on computed tomography(CT)and magnetic resonance imaging(MRI)may be used to classify panNEN.Contrast enhanced MRI and diffusion-weighted imaging have been reported to be useful for characterization of panNEN and quantifying metastatic burden.Current and emerging radiotracers have broadened the utility of functional imaging in evaluating panNEN.Fluorine-18 fluorodeoxyglucose positron emission tomography(PET)/CT and somatostatin receptor imaging such as Gallium-681,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid–octreotate PET/CT may be useful for improved identification of panNEN in comparison to anatomic modalities.These new techniques can also play a direct role in optimizing the selection of treatment for individuals and predicting tumor response based on somatostatin receptor expression.In addition,emerging methods of radiomics such as texture analysis may be a potential tool for staging and outcome prediction in panNEN,however further investigation is required before clinical implementation.
文摘BACKGROUND The management of rectal cancer patients is mainly based on the use of the magnetic resonance imaging(MRI)technique as a diagnostic tool for both staging and restaging.After treatment,to date,the evaluation of complete response is based on the histopathology assessment by using different tumor regression grade(TRG)features(e.g.,Dworak or Mandard classifications).While from the radiological point of view,the main attention for the prediction of a complete response after chemotherapy treatment focuses on MRI and the potential role of diffusion-weighted images and perfusion imaging represented by dynamiccontrast enhanced MRI.The main aim is to find a reliable tool to predict tumor response in comparison to histopathologic findings.AIM To investigate the value of dynamic contrast-enhanced perfusion-MRI parameters in the evaluation of the healthy rectal wall and tumor response to chemo-radiation therapy in patients with local advanced rectal cancer with histopathologic correlation.METHODS Twenty-eight patients with biopsy-proven rectal adenocarcinoma who underwent a dynamic contrast-enhanced MR study performed on a 1.5 T MRI system(Achieva,Philips),before(MR1)and after chemoradiation therapy(MR2),were enrolled in this study.The protocol included T1 gadolinium enhanced THRIVE sequences acquired on axial planes.A dedicated workstation was used to generate color permeability maps.Region of interest was manually drawn on tumor tissue and normal rectal wall,hence the following parameters were calculated and statistically analyzed:Relative arterial enhancement(RAE),relative venous enhancement(RVE),relative late enhancement(RLE),maximum enhancement(ME),time to peak and area under the curve(AUC).Perfusion parameters were related to pathologic TRG(Mandard’s criteria;TRG1=complete regression,TRG5=no regression).RESULTS Ten tumors(36%)showed complete or subtotal regression(TRG1-2)at histology and classified as responders;18 tumors(64%)were classified as non-responders(TRG3-5).Perfusion MRI parameters were significantly higher in the tumor tissue than in the healthy tissue in MR1(P<0.05).At baseline(MR1),no significant difference in perfusion parameters was found between responders and nonresponders.After chemo-radiation therapy,at MR2,responders showed significantly(P<0.05)lower perfusion values[RAE(%)54±20;RVE(%)73±24;RLE(%):82±29;ME(%):904±429]compared to non-responders[RAE(%):129±45;RVE(%):154±39;RLE(%):164±35;ME(%):1714±427].Moreover,in responders group perfusion values decreased significantly at MR2[RAE(%):54±20;RVE(%):73±24;RLE(%):82±29;ME(%):904±429]compared to the corresponding perfusion values at MR1[RAE(%):115±21;RVE(%):119±21;RLE(%):111±74;ME(%):1060±325];(P<0.05).Concerning the time-intensity curves,the AUC at MR2 showed significant difference(P=0.03)between responders and non-responders[AUC(mm2×10-3)121±50 vs 258±86],with lower AUC values of the tumor tissue in responders compared to nonresponders.In non-responders,there were no significant differences between perfusion values at MR1 and MR2.CONCLUSION Dynamic contrast perfusion-MRI analysis represents a complementary diagnostic tool for identifying vascularity characteristics of tumor tissue in local advanced rectal cancer,useful in the assessment of treatment response.
文摘Early detection of skeletal metastasis is critical for accurate staging and optimal treatment. This paper briefly reviews our current understanding of the biological mechanisms through which tumours metastasise to bone and describes the available imaging methods to diagnose bone metastasis and monitor response to treatment. Among the various imaging modalities currently available for imaging skeletal metastasis, hybrid techniques whichfuse morphological and functional data are the most sensitive and specific, and positron emission tomography(PET)/computed tomography and PET/magnetic resonance imaging will almost certainly continue to evolve and become increasingly important in this regard.
文摘患者女,56岁,因“双侧甲状腺乳头状癌”接受“甲状腺全切术+颈部淋巴结清扫术”后1月余;检出糖尿病3个月。查体:颈前见横向手术瘢痕,余未见明显异常。实验室检查:促甲状腺素(thyroid stimulating hormone,TSH)92.72μIU/ml,血清刺激性甲状腺球蛋白(thyroglobulin,Tg)>479ng/ml。行^(131)I清除残余甲状腺组织(简称清甲)治疗后全身显像(^(131)I post therapy whole body scan,Rx-WBS)见颈部多发淋巴结及双肺多发结节^(131)I浓聚。
