^18F-FDGPET/CT对孤立肺结节伴空洞鉴别诊断价值分析

目的：探讨^18F-FDG PET/CT对良恶性孤立肺结节伴空洞鉴别诊断可行性。方法：回顾性分析2009-08-06-2012-03-15华中科技大学附属协和医院50例单发肺结节伴空洞患者临床资料。根据结节CT特征和摄取FDG情况,并在PET图像中获取半定量指标最大标准摄取值（maximum Standardized uptake value,SUVmax）。分别计算CT、PET及PET/CT对病变良恶性诊断的准确性、敏感性、特异性、阳性预测值（positive predictive value,PPV）和阴性预测值（negative predictive value,NPV）,并进行χ^2检验,受试者工作特征（receiver operating characteristics,ROC）曲线进行分析。结果：50例患者中,23例证实为恶性病变,其中腺癌9例,鳞癌14例;27例为良性病变,其中肺脓肿14例,肺结核13例。CT诊断肺结节伴空洞良恶性敏感性为82.6%（19/23）,特异性为74.0%（20/27）,准确性78.0%（39/50）,PPV为73.0%（19/26）,NPV为83.3%（20/24）;PET诊断的敏感性为95.6%（22/23）,特异性为44.4%（12/27）,准确性为68.0%（34/50）,PPV为59.4%（22/37）,NPV为92.3%（12/13）;当选取SUVmax4.5为截断值时,敏感性为86.9%（20/23）,特异性为48.1%（13/27）,准确性为68.0%（34/50）,PPV为58.8%（20/34）,NPV为81.2%（13/16）;PET/CT联合诊断时敏感性为95.6%（22/23）,特异性为92.5%（25/27）,准确性为94.0%（47/50）,PPV为91.7%（22/24）,NPV为96.2%（25/26）。PET/CT对恶性和良性肺结节伴空洞诊断的准确率高于单独使用CT或PET,P〈0.01。结论：^18F-FDG PET对鉴别良恶性孤立肺结节伴空洞有较高的假阳性率,结合PET和CT形态学分析有助于提高病灶的诊断准确率。     

Differentiation of radiographically indeterminate solitary pulmonary nodules with

BACKGROUND: The purpose of this preliminary study was to evaluate the efficacy of positron emission tomography (PET) with [18F]fluoro-2-deoxyglucose (FDG) for differentiating benign from malignant solitary pulmonary nodules. METHODS: Twenty-six patients (12 females, 14 males, age 27-79 years) with radiographically indeterminate solitary pulmonary nodules underwent FDG-PET and the findings were compared with the results of pathological examination of biopsy samples. FDG activity in the lesion was expressed as the ratio of lesion-to-background counts (L/B ratio) for semiquantitative analysis. RESULTS: The mean L/B ratio of malignant lesions (8.81+/-3.71, n = 20) was not significantly higher than that of benign lesions (4.71+/-3.00, n = 6) (p = 1.00). Using a cut-off L/B ratio of 5.0 for malignancy, FDG-PET correctly detected 19 true positive and three true negative cases, but failed to detect three false positive (two abscesses and one cryptococcus) cases and one false negative (adenocarcinoma) case. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value were 95, 50, 86, 75 and 85%, respectively. CONCLUSIONS: FDG-PET is a sensitive modality for detecting malignancy, but is not specific enough. Benign lung lesion with active inflammation could demonstrate high FDG uptake, making it difficult to differentiate from malignancy. In the future, we will increase the case numbers to evaluate further the utility of FDG-PET for differentiating radiographically indeterminate solitary pulmonary nodules.     

99mTc-tetrofosmin SPECT in solitary pulmonary nodule evaluation

A correct differential diagnosis between benign and malignant lesions is mandatory in patients with solitary pulmonary nodule (SPN). The aim of the present study was to investigate whether 99mTc-tetrofosmin SPECT may play a role in SPN evaluation. A consecutive series of 111 patients with an uncalcified 相似文献   

^18F-FDG PET/CT双时相显像鉴别诊断肺良恶性病变的临床研究

[目的]探讨18F-FDGPET/CT双时相显像鉴别诊断肺良恶性病变的临床价值。[方法]65例肺病变患者（80个病灶）行18F-FDGPET/CT双时相显像,计算最大标准化摄取值SUVmax及早期、延迟显像SUVmax的变化幅度（ΔSUVmax）,并与病理及随访结果对比。利用ROC曲线计算SUVmax和ΔSUVmax诊断肺病变的最佳阈值。比较PET/CT与PET及CT的诊断效能。[结果]（1）65例共计80个肺内结节中良性结节38个,恶性结节42个。恶性结节组早期相SUVmax值为5.35（4.6）,高于良性结节组的1.75（2.0）,差异有统计学意义（Z=-4.846,P=0.0001）。恶性结节组双时相ΔSUVmax值为30.54（2.0）,高于良性结节组的16.84（2.0）,差异有统计学意义（Z=-2.861,P=0.0042）。（2）ROC分析显示早期显像SUVmax值〉2.45和双时相显像ΔSUVmax值〉24.66%是两者鉴别诊断肺良恶性结节时的最佳阈值。早期相SUVmax值〉2.45诊断肺恶性病变的灵敏度、特异性、准确率、阳性预测值和阴性预测值分别为88.10%、63.16%、76.25%、72.55%、82.76%,双时相ΔSUVmax值〉24.66%时,分别为64.29%、71.05%、67.50%、71.05%、64.29%。（3）PET/CT诊断肺病变的准确率优于PET和CT（P〈0.05）,诊断灵敏度优于CT（P〈0.05）。[结论]18F-FDGPET/CT诊断肺恶性病变,早期相SUVmax值及双时相ΔSUVmax值的最佳阈值为〉2.45和〉24.66%;并需结合病灶CT形态学特征及临床病史进行综合诊断。     

PET/CT双定量分析在良恶性颈部淋巴结鉴别诊断中的价值

  目的  探讨18F-FDG PET/CT SUVmax及CT短径双定量分析在良恶性颈部淋巴结鉴别诊断中的价值。  方法  回顾性分析本院2005年4月~2011年9月期间以颈部淋巴结肿大为首发症状行18F-FDG PET/CT检查的82例患者的显像情况。以病理诊断为金标准, 对CT、PET、PET/CT图像结果进行定量分析, 绘制SUVmax值及CT短径的ROC曲线, 找到最佳诊断界点, 分别计算单纯CT、单纯PET以及PET/CT双定量分析的敏感度、特异度、阳性预测值、阴性预测值、准确度等指标, 并对其结果进行统计学分析。  结果  当CT短径≥0.65cm且SUVmax≥1.95, 18F-FDG PET/CT显像诊断良恶性颈部淋巴结的灵敏度、特异度、阳性预测值、阴性预测值、准确度分别为79.30%、94.52%、95.15%、77.09%、85.76%, 其准确度高于单纯PET或单纯CT。  结论  18F-FDG PET/CT双定量分析对良恶性颈部淋巴结的鉴别诊断具有较高的临床价值, 其准确性优于单纯PET或单纯CT: 当CT短径≥0.65cm且SUV-max≥1.95.提示颈部淋巴结恶性可能性大。      

Efficacy of PET/CT in the characterization of solid or partly solid solitary pulmonary nodules

We aimed to evaluate the efficacy of (18)fluorine fluorodeoxyglucose ((18)F FDG) PET/CT for the characterization of solitary pulmonary nodules (SPNs) compared with the use of PET alone or CT alone. Our institutional review board approved this retrospective study with a waiver of informed consent. We selected 100 patients (M:F=56:44, mean age; 58 years) with a pathologically proven solid or partly solid SPN. Three chest radiologists assessed the nodule characteristics independently and retrospectively. Diagnostic efficacies were compared for three different approaches: consideration of CT findings only, PET findings only, and both PET and CT findings. The McNemar test, kappa statistics, and receiver operating characteristics (ROC) curve analysis were performed. Sixty patients had benign and 40 had malignant nodules. Overall sensitivity values for malignant SPNs for CT, PET and PET/CT were 82%, 88%, and 88%, respectively, whereas the specificity values were 66%, 71%, and 77%, respectively. PET/CT was significantly better in terms of specificity than the use of PET alone or CT alone (P<.05). The areas under curve (Az) values for the ROC analyses of PET/CT and PET alone, respectively, were larger than that of CT alone (P<.05). Interobserver agreement was moderate (kappa=0.46-0.56) for CT, good to excellent (kappa=0.78-0.90) for PET, and good for PET/CT (kappa=0.64-0.78). For the characterization of SPNs, integrated PET/CT provides significantly better specificity than CT alone or PET alone and both integrated PET/CT and PET alone allow more confidence than CT alone.     

基于螺旋CT影像的肺部毛玻璃结节的诊断价值

目的 探讨基于螺旋CT影像的肺部毛玻璃结节(pulmonary ground glass opacity nodule,GGO)的诊断价值.方法 采用回顾性研究方法,选择肺部毛玻璃结节患者58例作为研究对象,根据良恶性分为2组.观察2组的病灶界面、病灶边缘、病灶的形态、病灶大小及GGO的邻近结构.结果 2组中病灶大小、病灶边缘、病灶形态、病灶界面例数对比,差异有统计学意义(P<0.05);良性病变组的胸膜凹陷者0例,胸膜增厚者27例;恶性病变组的胸膜凹陷者16例,胸膜增厚者15例,2组对比有统计学意义(P<0.05).结论 多层螺旋螺旋CT可作为肺部毛玻璃结节良恶性的诊断方法.     

Can Dynamic Imaging,Using 18F-FDG PET/CT and CT Perfusion Differentiate Between Benign and Malignant Pulmonary Nodules?

BackgroundThe aim of the study was to derive and compare metabolic parameters relating to benign and malignant pulmonary nodules using dynamic 2-deoxy-2-[fluorine-18]fluoro-D-glucose (¹⁸F-FDG) PET/CT, and nodule perfusion parameters derived through perfusion computed tomography (CT).Patients and methodsTwenty patients with 21 pulmonary nodules incidentally detected on CT underwent a dynamic ¹⁸F-FDG PET/CT and a perfusion CT. The maximum standardized uptake value (SUV_max) was measured on conventional ¹⁸F-FDG PET/CT images. The influx constant (K_i) was calculated from the dynamic ¹⁸F-FDG PET/CT data using Patlak model. Arterial flow (AF) using the maximum slope model and blood volume (BV) using the Patlak plot method for each nodule were calculated from the perfusion CT data. All nodules were characterized as malignant or benign based on histopathology or 2 year follow up CT. All parameters were statistically compared between the two groups using the nonparametric Mann-Whitney test.ResultsTwelve malignant and 9 benign lung nodules were analysed (median size 20.1 mm, 9–29 mm) in 21 patients (male/female = 11/9; mean age ± SD: 65.3 ± 7.4; age range: 50–76 years). The average SUV_max values ± SD of the benign and malignant nodules were 2.2 ± 1.7 vs. 7.0 ± 4.5, respectively (p = 0.0148). Average K_i values in benign and malignant nodules were 0.0057 ± 0.0071 and 0.0230 ± 0.0155 min^-1, respectively (p = 0.0311). Average BV for the benign and malignant nodules were 11.6857 ± 6.7347 and 28.3400 ± 15.9672 ml/100 ml, respectively (p = 0.0250). Average AF for the benign and malignant nodules were 74.4571 ± 89.0321 and 89.200 ± 49.8883 ml/100g/min, respectively (p = 0.1613).ConclusionsDynamic ¹⁸F-FDG PET/CT and perfusion CT derived blood volume had similar capability to differentiate benign from malignant lung nodules.Key words: pulmonary nodule, perfusion, CT, dynamic, PET/CT     

PET/CT对981例肺结节的良恶性诊断价值分析

目的 探讨健康体检PET/CT对恶性肺结节的诊断意义,通过18F-脱氧葡萄糖(18F-FDG)高代谢灶摄取度判定肺部恶性肿瘤的价值.方法 回顾性分析981例肺结节患者的病例资料,包括良性肺结节966例,恶性肺结节15例.比较良恶性结节间病灶最大标准摄取值(SUVmax)之间的差异.结果 SUVmax≥2.5为PET/CT诊断恶性肿瘤的重要参考指标,PET/CT诊断灵敏度、特异度、准确度、阳性预测值及阴性预测值分别为86.7%(13/15)、99.4%(960/966)、99.2%(973/981)、68.4%(13/19)、99.8%(960/962).良性肺结节患者检查结果显示SUVmax为0~6.5,中位数为0.7,其中被误诊为恶性肺结节的患者分别是4例良性GGN经病理证实为坏死性肉芽肿(3例)/机化性肺炎(1例)、2例良性结节经病理证实为肺炎(1例)/纤维组织增生(1例);恶性肺结节患者检查结果显示SUVmax为0.8~16.3,中位数为4.7,其中恶性肺结节患者中2例肺泡癌患者漏诊.结论 18F-FDG PET/CT在筛 查肺部结节良、恶性诊断中有重要意义,SUVmax 对良、恶性程度的判断有指导意义.     

Inter-observer variations in FDG-PET interpretation for cancer screening

BACKGROUND: Diagnostic guidelines for the use of 2-(fluorine 18) fluoro-2 deoxy-D-glucose (FDG)-positron emission tomography (PET) in cancer screening have yet to be established. We assessed inter-observer variability in screening FDG-PET. METHODS: Subjects comprised 40 individuals who underwent FDG-PET and computed tomography (CT) for cancer screening. To assess various patterns of FDG uptakes, three subsets of the cases were selected: 'Cancer', 15 cases with cancer; 'Not malignant', 15 cases with suspected cancer by FDG-PET who were confirmed as cancer-free; and 'Normal', 10 cases without remarkable FDG uptake who were confirmed as cancer-free. A total of 68 lesions made up of malignancy (n = 18), benign (n = 21), and physiological FDG uptake (n = 29) were interpreted by six physicians. Each observer reviewed each case three times. Step 1 involved interpretation of PET images alone, Step 2 involved side-by-side reading of PET and CT images, and Step 3 involved re-evaluation of findings with the results of other screening tests. We assessed inter-observer agreement for each step. RESULTS: Inter-observer agreement for all lesions at each step was moderate, compared to fair agreement for 'Normal' subjects. Inter-observer agreement of 'Cancer' and 'Not malignant' subjects in Step 1 were better than those in Step 2 and 3; however, the differences were not statistically significant. CONCLUSION: The interpretation of FDG-PET is adequately reproducible, while that of 'Normal' subjects is less reproducible. Improvement of inter-observer variability in assessing physiological FDG uptakes requires universal reporting criteria in FDG-PET. Correlative interpretation of PET, CT and other information may require standardization in subjects with suspected cancer by FDG-PET.     

17例恶性肿瘤18氟脱氧葡萄糖PET显像假阴性的分析

目的 探讨恶性肿瘤^18氟脱氧葡萄糖（^18F—FDG）PET假阴性患者的FDG摄取特点、影响因素,分析PET／CT检查中CT对其的辅助诊断价值。方法 收集行PET／CT检查者中,^18F-FDGPET为阴性的17例恶性肿瘤患者,对其PET图像进行视觉观察和半定量分析,并与CT及病理检查结果进行对比分析。结果 6例肝癌患者病理证实为高分化型肝细胞肝癌,其中1例有两处病灶,一处病灶FDG摄取、平扫CT密度较周围正常肝组织低下,另一处病灶FDG摄取、平扫CT均为阴性;后行增强CT显示在动脉期两处病灶均明显强化。1例胃印戒细胞癌伴右侧附件转移患者,1例腹壁、大网膜转移性腺癌患者,3例肾透明细胞癌患者和1例前列腺癌患者（高分化型）的^18F—FDGPET诊断受消化道正常生理性FDG摄取或泌尿系统FDG滞留的影响。3例转移癌病变直径≤1cm,其中2例的原发病灶FDG摄取明显增高,1例原发病灶^18F—FDGPET及CT诊断为阴性。68．8％原发肿瘤、66．7％转移肿瘤在平扫CT上显示异常密度,并精确定位;而31．2％原发肿瘤、33．3％转移肿瘤病变^18 F—FDGPET及CT诊断均为阴性。结论恶性肿瘤^18F—FDGPET假阴性与病理学类型、分化程度及病灶大小有关;结合CT或重视PET显像方法可减少恶性肿瘤^18F—FDGPET假阴性。     

Diagnosis efficacy of structural (CT) and functional (FDG-PET) imaging methods in the thoracic and extrathoracic staging of non-small cell lung cancer

Purpose. To evaluate the efficacy of FDG-PET in the definition of tumour lung node lesions and to compare the diagnostic validity of CT and FDGPET in the staging of patients with non-small cell lung cancer (NSCLC). Material and methods. Patients with clinical suspicion of potentially resectable NSCLC (n = 108) were studied by standard procedures in our setting, including fibrobronchoscopy, transthoracic fine-needle aspiration, thoracoabdominal CT and FDG-PET. PET images were analysed by researchers blinded to results of other imaging modalities. Definitive tumour diagnosis was by histopathological study in patients who underwent surgery and by specific imaging methods and biopsy, when available, in patients who did not. Diagnostic accuracy was evaluated by comparing CT/PET results with the definitive diagnosis. Results. In 13% of patients, no FDG-PET findings were observed and the histological study was negative for tumour. In 22% of patients, FDG-PET detected metastatic disease (M0 by CT). For mediastinal involvement, global diagnostic accuracy was 0.90 with FDG-PET and 0.59 with CT. False positive FDG-PET findings were produced by inflammatory conditions and false negative findings by the small size or proximity of lymph nodes to primary tumour. Mediastinal staging by CT and FDG-PET was correct in 56% and 87% of patients, respectively. CT indicated mediastinal invasion in 17% of patients with no FDG-PET finding of mediastinal involvement. Conversely, mediastinal spread was undetected by CT in 14% of patients with FDG-PET findings of mediastinal involvement. Conclusions. Although complementary, the functional method (FDG-PET) is significantly superior to the structural method (CT) for detection of mediastinal tumour disease.     

The prevalence and clinical significance of 18F–2‐fluoro‐2‐deoxy‐D‐glucose (FDG) uptake in the thyroid gland on PET or PET‐CT in patients with lymphoma

F¹⁸–2‐fluoro‐2‐deoxy‐D‐glucose (FDG) positron emission tomography (PET) has become a well established tool in staging and assessing therapy response in lymphoma. Incidental thyroid uptake on PET is not uncommon and can pose a diagnostic and management challenge. We retrospectively evaluate the prevalence and clinical significance of incidental FDG uptake in the thyroid gland in patients with lymphoma. 1868 lymphoma patients underwent PET and PET‐CT between August 2002 and August 2008. 52 patients (2.8%) demonstrated FDG thyroid uptake (M = 17, F = 35; mean age 63 yr). Thyroid uptake was determined as focal or diffuse, maximum standardized uptake values (SUVmax) recorded as well as SUV max ratio compared to background mediastinum activity (SUVR). Corresponding CT findings on PET‐CT were evaluated independently. Results were correlated with clinical, histopathological and imaging follow‐up. 30 (1.6%) patients had focal thyroid uptake. 16 (53%) had histological confirmation either by surgery (n = 7) or FNA under USS (n = 9). The final diagnosis was benign in 12/30 patients and malignant in 9/30. The malignancy risk for focal thyroid uptake was 30%. Five patients had intercurrent thyroid cancer (four papillary, one microinvasive follicular) and four had lymphomatous involvement. There was no significant difference between the mean sizes of benign (23.7 mm, range 12–34) and malignant nodules (23.6 mm, range 8–48). The mean SUVmax of malignant and benign nodules was 4.4 (range 1.8–10.1) and 3.2 (range 1.8–6.9) respectively with no statistically significant difference. 22 (1.2%) patients had diffuse FDG uptake in thyroid and benign aetiology was found in all with adequate follow‐up (15/22). Focal FDG thyroid uptake on PET or PET‐CT in lymphoma patients warrants further investigations. The malignancy risk is 30% either due to intercurrent thyroid cancer or lymphomatous involvement. SUVmax, SUVR and CT attenuation characteristics are not helpful in distinguishing between benign and malignant aetiologies. Diffuse thyroid uptake has a benign aetiology. Copyright © 2010 John Wiley & Sons, Ltd.     

核医学正电子断层显像在肾肿瘤患者术前诊断中的作用

目的探讨PET在肾肿瘤术前诊断中作用。方法回顾性分析134例肾肿瘤患者PET图像。134例肾肿瘤术前评估患者中,32例行常规氟-18脱氧葡萄糖(18F-fluorodeoxyglucose,18F-FDG)PET或PET/CT显像(以下简称FDG-PET),51例行FDG-PET双时相显像,51例1周内分别行FDG-PET及碳-11乙酸盐(11C-acetate,AC)PET或PET/CT(以下简称AC-PET)双核素检查。收集其临床资料和影像检查结果。以病理结果为金标准。结果 FDG-PET对肾原发恶性肿瘤总的诊断准确率为48.5%,阳性预测值为96.3%,对透明细胞癌诊断准确率最低,为28.6%。对肾盂癌及其他恶性肿瘤诊断准确率为92.9%和75.0%。AC-PET对透明细胞癌诊断准确率93.5%。FDG-PET双时相显像60.0%阳性病灶标准摄取值(standard uptake value,SUV)升高,2例阴性病灶变为阳性。20例PET检查前其他检查发现肾外病灶的患者,检查后排除4例,并新发现6例患者肾外转移病灶。结论 FDG-PET检查对肾盂癌及其他恶性肿瘤诊断准确性高,对肾实质肿瘤诊断能力差,对肾肿瘤患者术前分期有帮助。AC-PET可弥补FDG-PET的不足。FDG-PET双时相显像不能从根本上解决FDG-PET对肾肿瘤诊断假阴性的问题。     

18F-FDG PET/CT对36例肺部病变的诊断价值初探

[目的]探讨PET/CT检查对肺内肿瘤的诊断价值.[方法]对36例患者用18F-FDG PET/CT进行全身显像,分别观察CT、PET及两者的同机融合图像.[结果]PET与CT均可发现大部肺内原发病灶及其转移灶,PET较CT多发现恶性病灶11处,CT则发现PET阴性的恶性病灶4处;融合图像显示两者融合较为准确,部分病灶两者的体积大小显示不等大;CT还可发现较多肺外的良性病灶.[结论]PET/CT一体机对肺内病灶及转移灶的诊断可综合两种检查方法的优势,提高诊断的效能.     

Diagnostic Performance of Diffusion Weighted Imaging of Malignant and Benign Pulmonary Nodules and Masses: Comparison with Positron Emission Tomography

Background: Diffusion-weighted imaging (DWI) makes it possible to detect malignant tumors based onthe diffusion of water molecules. However, it is uncertain whether DWI has advantages over FDG-PET fordistinguishing malignant from benign pulmonary nodules and masses. Materials and Methods: One hundredforty-three lung cancers, 17 metastatic lung tumors, and 29 benign pulmonary nodules and masses were assessedin this study. DWI and FDG-PET were performed. Results: The apparent diffusion coefficient (ADC) value(1.27±0.35 ×10-3 mm2/sec) of malignant pulmonary nodules and masses was significantly lower than that (1.66±0.58×10-3 mm2/sec) of benign pulmonary nodules and masses. The maximum standardized uptake value (SUVmax:7.47±6.10) of malignant pulmonary nodules and masses were also significantly higher than that (3.89±4.04) ofbenign nodules and masses. By using optimal cutoff values for ADC (1.44×10-3 mm2/sec) and for SUVmax (3.43),which were determined with receiver operating characteristics curves (ROC curves), the sensitivity (80.0%) ofDWI was significantly higher than that (70.0%) of FDG-PET. The specificity (65.5%) of DWI was equal to that(65.5%) of FDG-PET. The accuracy (77.8%) of DWI was not significantly higher than that (69.3%) of FDGPETfor pulmonary nodules and masses. As the percentage of bronchioloalveolar carcinoma (BAC) componentin adenocarcinoma increased, the sensitivity of FDG-PET decreased. DWI could not help in the diagnosis ofmucinous adenocarcinomas as malignant, and FDG-PET could help in the correct diagnosis of 5 out of 6 mucinousadenocarcinomas as malignant. Conclusions: DWI has higher potential than PET in assessing pulmonary nodulesand masses. Both diagnostic approaches have their specific strengths and weaknesses which are determined bythe underlying pathology of pulmonary nodules and masses.     

不同类型肺结节的生长曲线分析

背景与目的 计算机断层扫描(computed tomography,CT)随访评估肺内结节的生长特性是临床判断结节良恶性的常用策略.不同生物学行为的肺结节可能具有不同的生长速度和生长模式.本研究的目的是绘制不同类型肺结节的体积生长曲线,了解其生长方式,为判断结节性质并制定肺结节随访方案提供依据.方法 应用三维分析软件对111例接受2次及以上CT检查的肺结节(实性结节54例、亚实性结节57例)的影像资料进行回顾性分析.35例恶性及5例良性结节经病理或组织学确认,其余71例经两年随访无显著生长,经专家会诊确认为肺癌低危结节.所有结节按密度及性质分组:实性良性/低危结节、实性恶性结节、亚实性良性/低危结节、亚实性恶性结节.以随访间隔时间(d)为X轴,以随访结节的三维体积(mm3)和三维体积对数为Y轴,绘制体积线性及指数性生长曲线,由研究者主观观察曲线的形态.应用卡方检验比较不同性质肺结节的生长曲线的差异.结果 实性恶性结节中12例(66.7%)生长曲线快速上升,3例(16.7%)先平缓-后上升,2例(11.1%)缓慢上升,1例(5.56%)平直.亚实性恶性结节中8例(47.1%)呈快速上升型,4例(23.5%)缓慢上升,3例(17.6%)平直,2例(11.8%)为先下降-后上升型.实性良性/低危结节中5例(13.9%)呈下降型,17例(47.2%)平直,8例(21.6%)缓慢上升,6例(16.7%)呈波浪型.亚实性良性/低危结节中4例(10%)呈下降型,21例(52.5%)平直,9例(22.5%)缓慢上升,6例(15%)呈波浪型.良性/低危结节与恶性结节生长曲线分布存在显著性差异(χ2=42.4,P<0.01).结论 肺癌生长曲线具有异质性,快速上升是恶性肺结节的特征性生长曲线,但部分可在一定时期内表现为平直、缓慢上升甚至下降.缓慢生长不能排除肺癌可能,尤其是亚实性结节.     

Positron emission tomography (PET) for staging low-grade non-Hodgkin's lymphomas (NHL)

Although positron emission tomography (PET) imaging is now recognized as a useful tool for staging intermediate and high-grade non-Hodgkin's lymphoma (NHL), few data are available regarding its accuracy in low grade NHL. We therefore studied 36 patients with histologically proven low-grade NHL. Whole-body 2-(fluorine-18) fluoro-2-deoxy-D-glucose (FDG) PET was performed at the time of initial diagnosis (n = 21) or for disease recurrence (n = 15) prior to any treatment. PET results were compared to those of physical examination and computed tomography (CT). PET studies were read without knowledge of any clinical data. Any focus of increased activity was described and given a probability of malignancy using a 5 point-scale (0: normal to 4: definitively malignant). An individual biopsy was available for a total of 31 lesions. The sensitivity and specificity were 87% and 100% for FDG-PET, 100% and 100% for physical examination and 90% and 100% for CT respectively. In addition, 42 of 97 peripheral lymph node lesions observed by FDG-PET were clinically undetected, whereas the physical examination detected 23 additional nodal lesions. PET and CT both indicated 12 extranodal lymphomatous localizations. FDG-PET showed 7 additional extranodal lesions while 5 additional unconfirmed lesions were observed on CT. Regarding bone marrow infiltration, PET and biopsy were concordant in 24 patients with 11 true positive (TP) and 13 true negative (TN). However PET was FN in 11 patients and no biopsy was performed in one patient. The combination PET/CT/physical examination seems to be more sensitive than the conventional approach for staging low grade NHL. Its sensitivity however is unacceptably low for diagnosing bone marrow infiltration.     

Comparison of 18FDG-PET with CT scans in the evaluation of patients with residual and recurrent Hodgkin's lymphoma

The reliable assessment of residual masses after treatment as well as of new lesions suspected for relapse remains a diagnostic problem in patients with Hodgkin's disease (HD). The current study compares the results obtained by CT scan to FDG-PET imaging in a blind analysis with respect to the viability of residual masses and in case of suspected relapse. Between 1/94 and 10/99, 47 comparisons of PET and corresponding CT scans - 26 comparisons in 24 patients with residual tumors and 21 comparisons in 20 patients with suspected relapse of HD - were evaluated by independent reviewers blinded to he results of each other. Patients with primary diagnosis had been treated within trials of the German HD Trial study group. Relapsed patients received intensified salvage chemotherapy regimens. PET was assessed visually and by quantifying glucose uptake (SUV). Changes in size of tumor lesions as well as contrast medium enhancement served as criteria for assessment by CT scans. Results were validated either by histologic examination of a resected mass or biopsy (n=17) or by a clinical follow-up over 6 months following treatment (n=30). In 26 cases with residual lesions FDG-PET showed an increased tracer uptake in 8, 7 of which were true positive (TP) and 1 false positive (FP). Eighteen cases were classified as being negative (no viable HD), 17 true negative (TN) and 1 FN. In the blinded reading of the corresponding CT scans, 10 cases with residual lesions were considered to contain vital lymphoma (2 TP, 8 FP). Sixteen CT scans were classified as negative (10 TP, 6 FN). The resulting sensitivity and specificity of PET were 87.5% and 94.4% in contrast to only 25% and 56% for CT scans. The positive and negative predictive values of PET and CT scans were 87.5% and 94.4% and 20% and 62.5%, respectively. In patients with suspected relapse, sensitivity and positive predictive value for the diagnosis of the relapse were 100% and 86%, respectively, yielding the same results for both methods. FDG-PET performed in HD patients with residual masses appears to offer important additional information regarding the presence of viable HD in these residual lesions. In patients with suspected relapse of HD, FDG-PET seems not to offer any information over CT scans. Using SUVs is not superior to visual assessment of PET alone.     

磨玻璃型肺癌诊治研究进展

低剂量螺旋CT筛查可以降低肺癌致死率，同时随着计算机成像技术的普及，越来越多的人在行肺CT检查时发现肺内结节，其中有一部分表现为磨玻璃样阴影。磨玻璃样结节(ground-glass opacity，GGO)在胸部CT上表现为肺密度云雾样增高，但不掩盖支气管及肺血管结构的阴影。GGO是一种非特异性表现，病因包括肿瘤、感染、局部出血或间质纤维化等。近年来，表现为局灶性GGO的早期肺癌发病率逐渐增高，特别是亚洲、女性及非吸烟患者。因此，有必要对表现为GGO的结节进行良恶性鉴别，为临床治疗制定指导决策。