孤立性肺结节的诊断现状

孤立性肺结节的诊断现状,Solitary Pulmonary Nodule (SPN),定义：（coin leision） 任何肺内或胸膜的病灶，在X线上表现直径在2-30mm，边缘清晰或不清晰的圆形或类圆形阴影。 Fleischer Society Glossary 肺实质内直径3cm圆形或类圆形的病灶，不伴有淋巴结肿大，阻塞性肺炎或肺不张。 Chest 2003；123：89-96,概况,所有胸片 0.09%-0.20 150，000/年 （预计） 病因：肉芽肿性疾病、肺癌、错构瘤 恶性结节：1070占手术切除肺结节的60-80%，IA期肺癌术后5年生存率61-75 良性结节：感染性肉芽肿 80 错构瘤 10,Chest 2003；123：89-96,病因,Figure 1a. Rib fracture in a 50-year-old woman with multiple myeloma. (a) Close-up posteroanterior radiograph of the right upper lung shows a poorly marginated nodular area of increased opacity overlying the anterior aspect of the right second rib (arrow). (b) CT scan shows a healed fracture of the right second rib (arrow). Note the lytic lesions in the vertebral body secondary to multiple myeloma.,Figure 2a. Pseudonodule in a 50-year-old man. (a) Close-up posteroanterior radiograph of the right lung shows a smoothly marginated nodular area of increased opacity projecting over the lung (arrow). Note the adjacent electrocardiographic lead attachment pad (arrowhead). On a follow-up radiograph obtained after removal of the attachment pad (not shown), no nodule was observed. (b) Front and back views of the electrocardiographic lead attachment pad show an eccentrically located silver nitrate pad, which explains the contiguous nodular area of increased opacity on the chest radiograph.,Figure 3a. Bone island in a 61-year-old man with melanoma. (a) Close-up posteroanterior radiograph of the upper chest shows a focal area of increased opacity overlying the right seventh rib posteriorly (arrow). (b) Fluoroscopic images show a well-marginated intraosseous lesion (arrow). This finding is consistent with a bone island and obviated further investigation.,Figure 4a. Osteophyte of the left first rib in a 60-year-old woman. (a) Posteroanterior chest radiograph shows a poorly defined nodular area of increased opacity overlying the anterior aspect of the left first rib (arrow). (b) Posteroanterior chest radiograph obtained 2 years earlier shows that interval growth has occurred (cf a). This interval growth raised suspicion for malignancy. (c) Contiguous chest CT scans (image on right obtained at a lower level) reveal that the area of increased opacity is a large osteophyte of the first rib. Had fluoroscopy been performed, costly CT could have been avoided.,Figure 5a. Cutaneous nodules in a 51-year-old man with neurofibromatosis and prostatic adenocarcinoma. (a) Posteroanterior radiograph shows numerous well-marginated nodular areas of increased opacity projecting over the lower aspect of the thorax and a poorly marginated nodule overlying the upper aspect of the left hemithorax (arrow). Because the location of the upper nodule was uncertain, CT was performed. (b) CT scan helps confirm the intraparenchymal location of the nodule in the left upper lobe. (c) CT scan demonstrates multiple cutaneous nodules.,Figure 6a. Segmental bronchial atresia in a 17-year-old girl. (a) Close-up posteroanterior radiograph of the right lower lung shows a nodular area of increased opacity in the lower lobe (arrow). (b) Chest CT scans (image on left obtained at a lower level) show a branching tubular area of increased attenuation in the right lower lobe as well as pulmonary parenchyma with lower than expected attenuation. These findings are characteristic of segmental bronchial atresia and obviated further work-up.,Figure 7a. Multiple arteriovenous malformations in a 23-year-old woman with hereditary hemorrhagic telangiectasia. Contiguous chest CT scans reveal multiple small nodular areas of increased attenuation bilaterally with enlarged feeding and draining vessels, findings that are diagnostic for arteriovenous malformations. A chest radiograph obtained earlier (not shown) demonstrated a possible small solitary pulmonary nodule in the right lower lobe.,Figure 2a: (a) Chest radiograph shows an incidental small nodule (arrow) at the left costophrenic angle. (b) Thin-section CT scan shows central fat attenuation (43 HU) in the nodule. Hamartoma was diagnosed.,Figure 4: CT scan in a 90-year-old woman with chronic congestive heart failure shows a tiny nodule adjacent to the right major fissure that is likely to represent a congested intrapulmonary lymph node (arrow). Follow-up CT was not performed because of the patients advanced age.,胸部CT检测情况,Radiology 2003;228:70-75,SPN 恶性危险因素,SPN 大小,常规胸片仅能辨别直径9mm以上结节80良性结节直径小于2cm42恶性结节直径小于2cm， 15恶性结节直径小于1cm,直径8mm左右结节经随访恶性发生率10-20%,直径4mm结节恶性发生率5mm),良性空洞：壁光滑、薄(16mm) 15%肺癌有空洞（病灶直径3cm ）,Figure 16. Aspergillus infection in a 48-year-old man with leukemia. Close-up chest CT scan of the right lung shows a thin-walled cavitary nodule.,Figure 17. Squamous cell lung cancer in a 60-year-old woman. Close-up posteroanterior radiograph of the right lung shows a smoothly marginated nodule in the lower lobe. Note the eccentric cavitation and thick walls.,Figure 18: CT scan in an 83-year-old man shows a 2.3-cm left upper lobe cavitary nodule. The wall is variable and the cavity wall is as thick as 8 mm. FNAB revealed squamous cell carcinoma.,Figure 19: CT scan in an 80-year-old man shows a right upper lobe 2.9-cm cavitary nodule with a smooth, uniform 2.5-mm-thick cavity wall. FNAB revealed nonsmall cell lung cancer.,Figure 18. Bullet track from a gunshot wound in a 20-year-old man. Close-up posteroanterior radiograph of the right lung shows a smoothly marginated, thick-walled nodule with eccentric lucency in the midlung. Note the bullet fragments overlying the right lung. These findings are consistent with parenchymal hematoma and a bullet track.,空泡征：,空泡征为肿瘤内小的低密度影，多为23 mm大小，1个或多个，CT扫描仅限于12个层面见到。空泡征是未闭塞的小支气管或肺泡，主要原因同支气管空气征一样，为癌细胞呈伏壁生长，部分肺泡腔和细支气管未被肿瘤组织填充，肿瘤内的纤维组织或瘢痕组织的牵拉而扩张。多见于BAC或腺癌,支气管充气征,是指结节内见到充气的支气管，CT表现为气体密度小管影。此征多见于中高分化的腺癌，癌细胞沿着支气管呈伏壁生长，肺的支架结构未被破坏，肿瘤内的支气管结构仍保存。有此征象的肿瘤与无此征象的肿瘤相比，具有相对低度恶性的生物学行为。在恶性SPN的发生率为269 650 而在良性SPN，其发生率仅为00 59,SPN与支气管的关系,I型：支气管被SPN截断II型：支气管进入SPN呈锥状中断型：支气管在SPN内呈长段开放状，并可进一步分叉型：支气管紧贴SPN边缘走行，管腔形态正常V型：支气管紧贴SPN边缘走行，管腔受压变扁,Clinical Radiology (2004) 59, 11211127,恶性结节最常见的肿瘤一支气管关系是I型，其次为型，V型最少见；良性结节最常见的是V型，其次为I型，未见到型。就肿瘤一支气管关系类型而言，I型恶性SPN多于良性SPN，后者主要见于结核球；型仅见于恶性SPN；型可见于恶性和良性SPN，但前者的支气管形态僵硬，管腔保持通畅甚或轻度扩张；后者支气管形态柔软，走向自然，管腔扩张度不如恶性肿瘤，并常见支气管有多个树枝状分又及支气管呈断续状表现；IV型以恶性SPN占绝大多数V型则以良性SPN多见。,SPN一支气管关系类型的病理基础,膨胀性生长：瘤细胞增殖、堆积，呈实性压迫、推移邻近肺组织，由于肿瘤为支气管源性，故导致支气管在肿瘤边缘截断。伏壁性生长：以肺结构为支架，瘤细胞沿肺泡壁和肺泡隔爬行，经肺泡孔扩展，同时可经淋巴道、小气道或以直接浸润的方式从1个肺小叶扩展到另1个肺小叶，而支气管仍保持通畅，形成支气管充气征。,支气管管壁由外向内的肿瘤浸润、管壁产生的纤维性增殖性反应使支气管管壁增厚、僵硬，加上瘤内成纤维化反应的牵拉，使瘤内的支气管不仅未被肿瘤压扁，反而保持高度的通畅，甚至有所扩张，形成恶性肿瘤的含气支气管征特有的表现。良性结节边缘的支气管未受肿瘤侵犯和成纤维化反应的影响，管壁仍很柔软，易受膨胀性生长的结节压迫，导致管腔变扁甚至闭塞。结核球引起支气管截断是由于后者参与形成包膜。炎性假瘤的含气支气管征由肺实质的渗出、实变、机化衬托引起，支气管形态自然，常见树枝状分叉，管腔内可有分泌物、出血或血栓，使支气管表现为断续状。,SPN血管特征,恶性结节增强超过良性结节CT增强值低于15HU倾向于良性CT净增值超过25HU，清除值5-31HU倾向恶性,AJR 2007; 188:57-68,Graph of four different types of time-attenuation curve of nodule hemodynamics in consideration of both wash-in and washout phases of dynamic CT.,Radiology 2005;237:675-683,Patterns of Nodule Enhancement at Early and Delayed Enhancement CT,Patterns of Nodule Enhancement according to Histologic Diagnosis,Fig. 4A Metastatic adenocarcinoma in 57-year-old man with rectal cancer shows net enhancement of 25 H and washout of 5-31 H on dynamic helical CT and positive uptake on integrated PET/CT. Lung window of transverse thin-section (2.5-mm collimation) CT scan shows 9-mm nodule (arrow) in left upper lobe.,Fig. 3A Adenocarcinoma in 67-year-old man shows net enhancement of 25 H and washout of 5-31 H at dynamic helical CT and positive uptake at integrated PET/CT. Lung window of transverse thin-section (2.5-mm collimation) CT scan shows 16-mm nodule (arrow) in left upper lobe has lobulated and spiculated margin.,Figure 3a. CT scans of tuberculoma with type II enhancement (31 HU washout) in a 45-year-old woman. Serial images with dynamic enhancement curve for the left lower lobe nodule show peak enhancement is 165 HU; net enhancement, 133 HU; absolute loss of enhancement (washout), 90 HU; and time to peak enhancement, 1 minute.,Figure 1a. (a) Transverse, nonenhanced spiral CT image (3-mm collimation) through a relatively homogeneous 15-mm right upper lobe lung adenocarcinoma recurrence in a 71-year-old woman. Note the manually placed region of interest (1 ) on a nodule. The region of interest is positioned centrally, and its shape approximates that of the nodule on the cross-sectional image. Its net enhancement value was 14 HU. (b) Photomicrograph of this adenocarcinoma shows an appearance consistent with lymphangitic metastasis. Note the central zone of necrosis (arrows). There is little vascular stroma, which may have been a factor in its relatively low enhancement value. (Antibody to factor VIII-associated antigen; original magnification, x50.),周围型肺癌的血供源于支气管动脉，肿瘤间质内血管丰富，且分化不成熟，血管分布紊乱，基底膜不完整，管壁通透性高，有利于大分子造影剂渗入细胞间隙，部分肺癌微血管扩张，利于造影剂在血管内停留。炎性结节形成过程中，肺动脉水平上发生弥漫性血栓，血供直接源于支气管动脉，造影剂通过相对较直的、结构正常的血管进入间质，进入血管周围间质的造影剂因淋巴管的通畅加快了引流。部分恶性及良性病灶持续强化无清除可能与局部组织纤维化的程度数量相关。,病理学基础：,SPN生长速度评价,大部分恶性结节倍增时间30-400天2年随访病灶稳定，倍增时间至少730天倾向良性疾病倍增时间小于7天，超过465天倾向良性直径小于1cm病灶较难评价,Radiographics. 2000;20:59-66,计算公式,Td = Ti log 2/3 log(Di/Do) Ti = interval time Di = initial diameter Do= final diameter,Figure 1. Effect of initial nodule size on perception of growth. Schematic illustrates two volume doublings of a 4-mm nodule and a 3-cm nodule. Because the eye perceives the arithmetic increase in diameter rather than the change in volume, the smaller nodule appears to be growing more slowly than the larger one, even though both are doubling in volume at the same rate.,Figure 21a: (a) CT scan in an 80-year-old man shows a 2.5-cm right upper lobe nodule at the posterior segment. (b) Repeat CT scan obtained prior to treatment performed 2 months later shows rapid interval enlargement. The volumetric doubling time was 26 days. FNAB revealed mixed small cell and nonsmall cell carcinoma.,Bayesian Analysis,根据临床资料和影像学特征计算pCapCa0.90 手术,N Engl J Med 2003 Jun 19;348(25):2535-42,Effect of age and smoking history on pCa in an indeterminate pulmonary nodule. Close-up chest CT scan of the right lung shows a 7-mm, smoothly marginated, noncalcified nodule in the middle lobe. On the basis of decision analysis, observation would be the most cost-effective management strategy