孤立性肺结节：良性与恶性对比.ppt

Solitary pulmonary nodule:benign versus malignant 孤立性肺结节：良性与恶性对比,The differential diagnosis of a solitary pulmonary nodule is broad and management depends on whether the lesion is benign or malignant.孤立性肺结节的鉴别诊断是很多的，处理方法依赖于该病变是良性还是恶性In this overview we will discuss some of the new features that can help to differentiate between benign and malignant nodules based upon CT and PET-CT findings.在此篇文章，我们着重讨论下一些有助于鉴别良恶性结节的新特征，此特征是基于CT与PET-CT的检查结果,CT:benign versus malignant,Calcification Size Growth Shape Margin Air Bronchogram sign Solid and Ground-glass components Contrast enhancement,CT:良性与恶性,钙化大小生长速度形状边缘支气管含气征实性或磨玻璃样增强特征,Calcification 钙化,Diffuse,central,laminated or popcorn calcifications are benign patterns of calcification.弥漫性，中心性，分层，爆米花钙化是良性钙化，,These types of calcification are seen in granulomatous disease and hamartomas这些形式的钙化最常见于错构瘤、肉芽肿性病变,The exception to the rule above is when patients are known to have a primary tumor.For instance the diffuse calcification pattern can be seen in patients with osteosarcoma or chondrosarcoma.Similarly the central and popcorn pattern can be seen in patients with GI-tumors and patients who previously had chemotherapy.一些病人有原发肿瘤病史，可以表现为良性钙化例如骨肉瘤、软骨肉瘤可以表现弥漫性钙化。胃肠间质瘤的病人化疗后可以表现为中心性或苞米花钙化。,Size 大小,A solitary pulmonary nodule(SPN)is defined as a single intraparenchymal lesion less than 3 cm in size and not associated with atelectasis or lymphadenopathy.A lesion greater than 3 cm in diameter is called a mass.孤立性结节定义为小于3cm，不伴有肺不张、淋巴结转移，大于3cm的为肿块This distinction is made,because lesions greater than 3 cm are usually malignant,while smaller lesions can be either benign or malignant.以3cm为界，因为大于3cm的通常是恶性的，而小于3cm的可能是良性或恶性。,Relationship between SPN-size and chance of malignancy in patients with high risk for lung cancer结节大小与恶性度具有密切相关性,Growth 生长速度,Comparison with prior imaging studies is often the most useful procedure to determine the importance of the finding of a SPN,since stability over 2 years is highly associated with benignity.与前次影像结果相比是鉴别孤立性结节良恶性的一个非常有用的方法。如果超过2年以上保持不变，这个结节就是良性结节,Shape 形态,Japanese screening studies showed that a polygonal shape and a three-dimensional ratio 1.78 was a sign of benignity(2,3).日本的一项研究表明，多变形和三维立体比率大于1.78是良性结节的标志A polygonal shape means that the lesion has multiple facets(multi-sided).多边形意味这个病灶具有多个面A peripheral subpleural location was also a sign of benignity in this study 在这项研究中，周围的胸膜下的病变也是良性结节的一个标志,The three-dimensional ratio is measured by obtaining the maximal transverse dimension and dividing it by the maximal vertical dimension.A large three-dimensional ratio indicates that the lesion is relatively flat,which is a benign sign.,Margin 边缘,Corona radiata sign-highly associated with malignancy(figure)放射冠征Lobulated or scalloped margins-intermediate probability 分叶征和锯齿征,Smooth margins-more likely benign unless metastatic in origin 边缘光滑见于良性结节，除外转移瘤,Air Bronchogram sign空气支气管征,Recent studies have showed that an air bronchogram is more commonly seen in malignant pulmonary nodules.It is most commonly seen in BAC(bronchoalveolar cell carcinoma)and adenocarcinoma.最近一项研究表明，在恶性结节中经常看见空气支气管征，主要见于支气管肺泡癌或腺癌,The case on the left shows an airbronchogram seen as a linear lucency(broad arrow)and as a more cystic lucency(small arrow)due to the fact that the bronchus is seen en face.,On the left two solitary pulmonary nodules.Based upon the morphology,which lesion has the most malignant features?下列两个结节有哪些恶性特征呢,The lesion on the far left has a spicuated margin and has lucencies within it.The lesion next to it is lobulated in contour and has some spicules radiating to the pleura.It is however homogeneous in attenuation.Based on these findings we should be most concerned that the lesion on the far left is malignant.It proved to be an adenocarninoma,while the other one was a fungal infection.The lucencies and frank air bronchograms should not mislead you in thinking that it probably is infection.,Solid and Ground-glass components实性与磨玻璃样,Another result from screening studies is that nodules containing a ground-glass component are more likely to be malignant(5).另一项研究表明，含有磨玻璃样密度的结节很可能是恶性结节。Partly solid lesions with ground-glass components had a malignancy rate of 63%.部分实性和磨玻璃样密度是恶性结节的可能性事63%Nonsolid-only ground-glass lesions had a malignancy rate of 18%.完全磨玻璃样密度结节16%是恶性结节Only solid lesions had a malignancy rate of only 7%.完全实性结节是仅7%是恶性结节,Partly solid nodule containing ground-glass component most likely to be malignant,On the far left a lesion that only has a ground-glass appearance and next to it a lesion that has both ground-glass and solid components.The likelihood of malignancy is 1:5 for the lesion on the far left and 2:3 for the lesion with both ground-glass and solid components.,LEFT:1 in 5 malignant左边图是5个病灶1个为恶性结节RIGHT:2 in 3 malignant右边图是3个病灶2个为恶性结节,Contrast enhancement对比增强,Contrast enhancement less than 15 HU has a very high predictive value for benignity(99%).After a baseline scan,4 consecutive scans at 1 minute interval are performed.对比增强小于15HU是良性病变的可能性（99%）,This applies only for nodules with the following selection criteria:Nodule 5mm 结节大于5mmRelatively spherical 相对圆形Homogeneous,no necrosis,fat or calcification均匀，无坏死、钙化 No motion or beam hardening artifacts 没有运动、硬射线伪影,PET-CT:benign versus malignant,PET-CT plays an increasingly important role in the evaluation of solitary nodules.PET-CT在肺结节的评价中起着很重要作用,PET has a very high sensitivity 95%,but a lesser specificity of only 81%PET有很高的敏感性95%，但特异性仅为81%PET is false positive in granulomatous disease PET是假阳性在炎症性疾病中国PET is usually false negative in size 10 mm and low-grade malignancy including bronchoalveolar carcinoma and carcinoid 当病变小于19 mm时或低度恶性时，PET表现为假阴性，包括支气管肺泡癌和类癌,False negative PET in a patient with adenocarcinoma.Activity is not sufficient for the diagnosis malignancy.,Conclusion结论,In the differentiation of benign versus malignant solitary pulmonary nodules nowadays new imaging features have to be added.We especially have to look for the presence of areas of ground-glass opacity,air bronchograms or cavities and the three-dimensional ratios of a lesion.在肺结节的鉴别诊断中，一些征象将被增加，包括磨玻璃密度、空气支气管征、空洞及三维立体比率,With the increasingly important role of PET-CT,we have to be aware of the accuracy of PET-CT and we should have an idea about the prevalence of infectious and non-infectious granulomatous disease in the area that we practice.我们应该充分意识到PET-CT的重要性，在实践诊断中应该注意感染性与 非感染性疾病的流行情况,References,CT Screening for Lung Cancer:Five-year Prospective Experience Stephen J.Swensen et al Radiology 2005;235:259-265.Indeterminate Solitary Pulmonary Nodules Revealed at Population-Based CT Screening of the Lung:Using First Follow-Up Diagnostic CT to Differentiate Benign and Malignant Lesions Shodayu Takashima et al.AJR 2003;180:1255-1263 Small Solitary Pulmonary Nodules(1 cm)Detected at Population-Based CT Screening for Lung Cancer:Reliable High-Resolution CT Features of Benign Lesions Shodayu Takashima et al.AJR 2003;180:955-964 CT Screening for Lung Cancer Frequency and Significance of Part-Solid and Nonsolid Nodules Claudia I.Henschke et alAJR 2002;178:1053-1057,