The role of positron emission tomography in evaluating mediastinal lymph node metastases in non-small-cell lung cancer

Positron emission tomography (PET) is a modality that differentiates malignant from benign processes based upon metabolism rather than anatomy. A number of studies have confirmed improved accuracy of PET over computed tomography (CT), but until a few recent studies, most had failed to include satisfactory histologic confirmation. The objective of this study was to compare PET and CT to histologic staging of the mediastinum in patients with non-small-cell lung cancer (NSCLC). Histologic examination of mediastinal lymph nodes (MLNs) was performed on 40 patients with NSCLC at mediastinoscopy and/or at surgical resection. PET scans were interpreted by one of two nuclear medicine physicians, blinded to histology, using CT scans for anatomic localization. CT scans were independently evaluated for mediastinal lymphadenopathy. The overall accuracy, sensitivity, and specificity of PET were 78% (31 of 40), 67% (four of six), and 79% (27 of 34), respectively. The overall accuracy, sensitivity, and specificity of CT were 68% (27 of 40), 50% (three of six), and 71% (24 of 34), respectively. PET was superior to CT at correctly identifying mediastinal nodal metastases; however, both modalities were inferior to the gold standard of surgical staging. PET is more accurate than CT in staging the mediastinum of patients with NSCLC. PET failed to identify lymph node metastasis in 33% of patients with histologically proven MLN involvement, and false positives were present in 15%. At present, mediastinoscopy should remain the standard of care for preoperative mediastinal staging for NSCLC.     

FDG-PET/CT imaging for staging and target volume delineation in preoperative conformal radiotherapy of rectal cancer

PURPOSE: To investigate the potential impact of using (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) on staging and target volume delineation for patients affected by rectal cancer and candidates for preoperative conformal radiotherapy. METHODS AND MATERIALS: Twenty-five patients diagnosed with rectal cancer T3-4 N0-1 M0-1 and candidates for preoperative radiotherapy underwent PET/CT simulation after injection of 5.18 MBq/kg of FDG. Clinical stage was reassessed on the basis of FDG-PET/CT findings. The gross tumor volume (GTV) and the clinical target volume (CTV) were delineated first on CT and then on PET/CT images. The PET/CT-GTV and PET/CT-CTV were analyzed and compared with CT-GTV and CT-CTV, respectively. RESULTS: In 4 of 25 cases (24%), PET/CT affected tumor staging or the treatment purpose. In 3 of 25 cases (12%) staged N0 M0, PET/CT showed FDG uptake in regional lymph nodes and in a case also in the liver. In a patient with a single liver metastasis PET/CT detected multiple lesions, changing the treatment intent from curative to palliative. The PET/CT-GTV and PET/CT-CTV were significantly greater than the CT-GTV (p = 0.00013) and CT-CTV (p = 0.00002), respectively. The mean difference between PET/CT-GTV and CT-GTV was 25.4% and between PET/CT-CTV and CT-CTV was 4.1%. CONCLUSIONS: Imaging with PET/CT for preoperative radiotherapy of rectal cancer may lead to a change in staging and target volume delineation. Stage variation was observed in 12% of cases and a change of treatment intent in 4%. The GTV and CTV changed significantly, with a mean increase in size of 25% and 4%, respectively.     

Accuracy of helical computed tomography and [18F] fluorodeoxyglucose positron emission tomography for identifying lymph node mediastinal metastases in potentially resectable non-small-cell lung cancer.

PURPOSE: Computed tomography (CT) and [18F] Fluorodeoxyglucose positron emission tomography (FDG-PET) are considered suitable methods for the noninvasive staging of the mediastinum. Our study was intended to estimate the efficacy of contrast-enhanced helical CT (hCT) and FDG-PET, alone and combined, in the diagnosis of lymph node mediastinal metastases. METHODS: This study was a prospective and blind comparison of the efficacy of hCT and FDG-PET with two alternative reference standards, mediastinoscopy, and mediastinoscopy plus thoracotomy plus a 6-month follow-up to diagnose lymph node mediastinal metastases in 132 consecutive patients with potentially resectable non-small-cell lung cancer (NSCLC). The metastatic disease was assessed histopathologically. Further clinical information was obtained postoperatively after a median follow-up of 42 months. RESULTS: The prevalence of cN2,3 is 0.28. For hCT the sensitivity and specificity are 0.86 (95% CI, 0.70 to 0.93) and 0.67 (95% CI, 0.56 to 0.75), for PET 0.94 (95% CI, 0.81 to 0.98) and 0.59 (95% CI, 0.49 to 0.68), and for hCT and PET combined in-parallel 0.97 (95% CI, 0.84 to 0.99) and 0.44 (95% CI, 0.34 to 0.53), which translate into a negative predicted probability of 0.98 (95% CI, 0.88 to 1.00). The crude diagnostic odds ratio of PET in the total sample studied is 13.1, in the subgroup hCT+ 11.04 (3.0 to 40 0.1), and in the hCT- 3.5 (0.5 to 21.5). Similar results were obtained for hCT stratified by PET. CONCLUSION: hCT and PET perform similarly in the mediastinal staging of NSCLC, both tests are conditionally dependent and provide complementary information, and their diagnostic value mainly resides on the negative results.     

The additional value of integrated PET/CT over PET in initial lymph node staging of esophageal cancer

The purpose of the present study was to assess the contribution of simultaneous functional/anatomical imaging using integrated 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT), compared with PET alone for the evaluation of initial lymph node staging in esophageal cancer. We studied 167 consecutive patients with thoracic esophageal squamous cell carcinoma (SCC) who had radical esophagectomy performed between January 1999 and April 2007. For individual nodal group evaluation, PET/CT showed 46.0% sensitivity (p<0.05 vs. PET), 99.4% specificity, 95.1% accuracy (p<0.05 vs. PET), 87.0% positive and 95.5% negative predictive values. PET showed 32.9% sensitivity, 98.9% specificity, 93.1% accuracy, 74.7% positive predictive value and 93.9% negative predictive value. Thus, the sensitivity and accuracy of PET/CT were significantly higher than those of PET. Comparisons between CT, PET and PET/CT in detecting lymph node metastasis by each region showed that PET/CT had a higher sensitivity in lower thoracic regions than PET and CT (p<0.05 vs. CT and PET). Lymph node staging (N0 vs. N1) was not significantly different, but staging per lymph nodal group was significantly better with PET/CT. Integrated PET/CT imaging with co-registration of anatomic and functional imaging data is useful in the initial lymph node staging of patients with operable esophageal cancer compared with PET alone.     

Accuracy and clinical impact of mediastinal lymph node staging with FDG-PET imaging in potentially resectable lung cancer

To determine the sensitivity, specificity, and accuracy of staging mediastinal nodal disease in potentially resectable lung cancer using fluorodeoxyglucose-positron emission tomography (FDG-PET), computed tomography (CT), or both and compare these results to surgical staging. We also assessed whether PET scanning results changed clinical management. From 1992 to 1997, 50 patients underwent CT, and PET scanning before or close to the time of surgical staging. Sensitivity, specificity, accuracy, and predictive values were then calculated based on pathology results. A retrospective review of the records was performed to determine how PET results affected clinical treatment decisions. Forty-seven of 50 patients had non-small-cell lung cancer. The prevalence of pathologically confirmed mediastinal and hilar involvement was 38%. The sensitivity, specificity, and accuracy of mediastinal disease staging were as follows: CT alone = 73%, 77%, 76%; PET alone = 73%, 94%, 87%; PET + CT = 82%, 96%, 91%, respectively. PET was more specific and accurate than CT (p = 0.025). The results of PET changed management decisions in 12 of 50 cases (24%). Using FDG-PET in conjunction with CT scanning provides the most accurate staging of mediastinal disease in lung cancer by contributing complementary information. Furthermore, PET can affect clinical decision-making and allow some patients considered unresectable a chance for resection.     

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.     

Positron emission tomography for staging of oesophageal and gastroesophageal malignancy.

Positron emission tomography (PET) with [18F]-fluoro-2-deoxy-D-glucose (FDG) was prospectively investigated as a means of detecting metastatic disease in patients with oesophageal tumours and compared with computerized tomography (CT), with the surgical findings as a gold standard. Twenty-six patients with a malignant tumour of the oesophagus or gastroesophageal junction underwent CT and PET of the chest and the abdomen. Seven patients underwent laparoscopy to establish resectability. Fifteen patients underwent laparotomy without prior laparoscopy. Four patients did not undergo surgery. The primary tumour was visualized in 81% of patients with CT and in 96% with PET. Neither CT nor PET were suited to assess the extent of wall invasion. Surgically assessed nodal status corresponded in 62% with CT and in 90% with PET. Distant metastases were found in five patients with CT and in eight with PET. The diagnostic accuracy of CT in determining resectability was 65% and for PET 88%. For CT and PET together this was 92%. The present study indicates that FDG-PET can be of importance for staging patients with oesophageal tumours. PET has a higher sensitivity for nodal and distant metastases and a higher accuracy for determining respectability than CT. PET and CT together would have decreased ill-advised surgery by 90%.     

2-(fluorine-18)fluoro-2-deoxy-D-glucose positron emission tomography in the detection and staging of malignant lymphoma. A bicenter trial

BACKGROUND: The authors undertook a prospective evaluation of the clinical value of 2-fluoro [18-]-2-deoxyglucose positron emission tomography (FDG-PET) in the detection and staging of malignant lymphoma compared with computed tomography (CT) and bone marrow biopsy (BMB). METHODS: Fifty-two consecutive patients with untreated malignant lymphoma were evaluated prospectively in a bicenter study. FDG-PET, CT, and BMB were performed for investigating lymph node/extranodal manifestations and bone marrow infiltration. Thirty-three percnt of the discrepant results were verified by biopsy, magnetic resonance imaging, or clinical follow-up (range, 4-24 month). RESULTS: Altogether, 1297 anatomic regions (lymph nodes, organs, and bone marrow) were evaluated. FDG-PET and CT scans were compared by receiver operating characteristic (ROC) curve analysis. The area under the ROC curve were as follows: lymph nodes, 0.996 (PET) and 0.916 (CT); extranodal, 0.999 (PET) and 0.916 (CT); supradiaphragmatic, 0.996 (PET) and 0.905 (CT); and infradiaphragmatic, 0.999 (PET) and 0.952 (CT). In these analyses, FDG-PET was significantly superior to CT (P < 0.05), except in infradiaphragmatic regions, in which the two methods produced equivalent results. In detecting bone marrow infiltration, FDG-PET was superior to CT and was equivalent to BMB. In 4 of 52 patients (8%), FDG-PET led to an upstaging and a change of therapy. CONCLUSIONS: Noninvasive FDG-PET is very accurate in the staging of malignant lymphoma. Compared with standard staging modalities (CT and BMB), PET was significantly superior and led to changes in the therapy regimen for 8% of patients.     

食管癌IMRT前FDG PET-CT显像对治疗决策的影响

目的 探讨食管癌初治患者IMRT前PET-CT显像对其治疗方案的影响。方法 回顾分析60例经食管镜检证实的食管癌患者,患者均为初次治疗,经常规影像检查后拟行IMRT。放疗前行PET-CT显像,观察是否有分期和治疗方案改变。结果 与常规影像比,PET-CT显像使12例患者分期发生改变(2例T期上调、6例N期上调、2例N期下调、2例M期上调)。3例患者由于新发现较多的远处转移,治疗方案由放疗改为化疗。PET-CT检查导致20例患者靶区改变,其中16例因发现更多转移淋巴结使靶体积增大,4例则排除了淋巴结转移使靶区缩小。结论 PET-CT对食管癌区域淋巴结和远处转移诊断有一定优势,有助提高分期准确性,改变了部分患者治疗决策方案。     

The incremental effect of positron emission tomography on diagnostic accuracy in the initial staging of esophageal carcinoma

BACKGROUND: The purpose of the current study was to assess whether [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) provides incremental value (e.g., additional information on lymph node involvement or the presence of distant metastases) compared with computed tomography (CT) in patients with esophageal carcinoma. METHODS: The authors examined 149 consecutive patients with thoracic esophageal carcinoma. Eighty-one patients underwent radical esophagectomy without pretreatment, 17 received chemoradiotherapy followed by surgery, 3 underwent endoscopic mucosal resection, and the remaining 48 patients received definitive radiotherapy and chemotherapy. The diagnostic accuracy of FDG-PET and CT was evaluated at the time of diagnosis. RESULTS: The primary tumor was visualized using FDG-PET in 119 (80%) of 149 patients. Regarding lymph node metastases, FDG-PET had 32% sensitivity, 99% specificity, and 93% accuracy for individual lymph node group evaluation and 55% sensitivity, 90% specificity, and 72% accuracy for lymph node staging evaluation. PET exhibited incremental value over CT with regard to lymph node status in 14 of 98 patients who received surgery: 6 patients with negative CT findings were eventually shown to have lymph node metastases (i.e., they had positive PET findings and a positive reference standard [RS]); 6 patients with positive CT findings were shown not to have lymph node metastases (i.e., they had negative PET findings and a negative RS); and 2 patients were shown to have cervical lymph node metastases in addition to mediastinal or abdominal lymph node metastases. Among the remaining patients, PET showed incremental value over CT with regard to distant organ metastases in six patients. The overall incremental value of PET compared with CT with regard to staging accuracy was 14% (20 of 149 patients). CONCLUSIONS: FDG-PET provided incremental value over CT in the initial staging of esophageal carcinoma. At present, combined PET-CT may be the most effective method available for the preoperative staging of esophageal tumors.     

Comparison between positron emission tomography and computed tomography in the use of the assessment of esophageal carcinoma

BACKGROUND: The role and potential value of positron emission tomography (PET) scanning in certain tumors has been widely investigated in recent years. The authors retrospectively assessed the performance of 18-F-fluorodeoxyglucose (FDG)-PET in the assessment of esophageal squamous cell carcinoma (SCC). METHODS: The results using PET were compared with those using computed tomography (CT), and these were correlated with the pathologic findings. The authors studied 32 patients with thoracic esophageal SCC who had undergone radical esophagectomy. RESULTS: Uptake of FDG in the primary tumor was found in 25 of the 32 (78.1%) cases. Comparison of the FDG uptake and the clinicopathologic findings showed that there was a significant association between the FDG uptake and each of the depth of tumor invasion (P < 0.05), occurrence of lymph node metastasis (P < 0.01), and lymphatic invasion (P < 0.01). The survival rate in cases with high FDG uptake (standardized uptake value [SUV], >3) was significantly lower than that in cases with low FDG uptake (SUV, < 3; P < 0.05). In the evaluation of lymph node staging by the detection of lymph node metastasis, FDG-PET showed 77.8% sensitivity, 92.9% specificity, and 84.4% accuracy, and CT scanning showed 61.1% sensitivity, 71.4% specificity, and 65.6% accuracy. Positron emission tomography scanning showed a high degree of accuracy in the neck, upper thoracic, and abdominal regions. However, in the mid- and lower thoracic regions, the sensitivity was very low. The smallest lymph node metastasis that was detected by FDG-PET imaging was 6 mm. The average size of lymph node metastasis that was undetected by FDG-PET scanning was 7.3 mm (range, 1-17 mm). CONCLUSIONS: In conclusion, FDG-PET may be used as a noninvasive diagnostic technique in assessing the aggressiveness of the tumor and the prognosis in patients with esophageal SCC. During the preoperative diagnostic procedures, the sensitivity, specificity, and accuracy of lymph node staging is higher with FDG-PET than with CT imaging. In view of the high specificity of FDG-PET, it also gives useful information to guide the choice of treatment of esophageal carcinoma.     

PET/CT与MRI在鼻咽癌淋巴结转移诊断和N分期中的比较研究

目的 比较PET／CT与MRI在鼻咽癌淋巴结转移诊断和N分期中的作用。方法116例鼻咽癌患者于治疗前行PET／CT和MRI检查。依据随访结果比较PET／CT和MRI在淋巴结转移诊断和N分期中的作用。结果116例患者的614个淋巴结的随访结果显示,阳性340个,阴性274个。PET／CT诊断转移淋巴结的敏感性、特异性及准确性分别为93．2％、98．2％和95．4％,而MRI分别为88．8％、91．2％和89．9％,两者各指标比较,差异有统计学意义（P〈0．05）。按1992年福州分期,109例（94．0％）的PET／CT分期正确,103例（88．8％）的MRI分期正确;按UICC分期,108例（93．1％）的PET／CT分期正确,100例（86．2％）的MRI分期正确。结论PET／CT判断鼻咽癌淋巴结转移和N分期较MRI准确,但对炎性增生、大面积坏死淋巴结,或直径小于PET空间分辨率的转移淋巴结应警惕其假阳性和假阴性判断。     

术前CT检查在可手术非小细胞肺癌TNM分期中的应用评价

目的比较术前CT检查和术后病理诊断的非小细胞肺癌TNM分期结果,评价术前CT检查对非小细胞肺癌TNM分期的临床参考价值。方法112例临床确诊为NSCLC的患者行术前螺旋CT检查,临床分期为Ⅰ～ⅢA患者行手术切除加系统性淋巴结清扫,术前CT检查对TNM的分期结果定义为临床TNM（cTNM）,术后的病理分期定义为病理TNM（pTNM）。对比患者的cTNM与pTNM,评价术前CT检查确定非小细胞肺癌TNM分期的敏感度、特异性和准确率。结果（1）术前CT检查诊断T分期的敏感度和特异性分别为76.6％和85.7％,阳性预测值为92.2％,阴性预测值为62.5％,准确率为79.5％。一致性检验有统计学意义（Kappa=0.658,P<0.05）;（2）术前CT检查诊断纵隔淋巴结转移的敏感度和特异性分别为72.9％和84.9％,阳性预测值为84.3％,阴性预测值为73.8％,准确率为78.6％,一致性检验有统计学意义（Kappa=0.667,P<0.05）。螺旋CT检查诊断 4R、5、6 组纵隔淋巴结转移的准确率和特异性偏低,其中4R组淋巴结转移的假阳性和假阴性较高。结论术前CT检查对非小细胞肺癌TNM分期有重要的临床参考价值,但存在假阳性和假阴性,应结合其他检查手段如PET-CT或纵隔镜等提高术前TNM分期准确率。     

18FDG-PET对大肠癌分期、再分期诊断的价值

目的:评价18FDG-PET(18氟标记脱氧葡萄糖-正电子发射断层扫描)对大肠癌分期及术后再分期的价值。方法:对24例经肠镜检查初步诊断为直肠、结肠癌的患者行全身18FDG-PET检查,并在1～2W内完成手术及病理诊断。大肠癌术后18FDG-PET随访56例。结果:24例病理证实为大肠癌,23例局部18FDG摄取增高,SUVmax=7.09±3.26,2.98～12.2(SUV,Standarduptakevalue)。18FDG-PET对于肿瘤原发病灶诊断准确率为95%(23/24)。假阴性1例。单纯局部(主要为第1站)淋巴结转移8例(灵敏度8/16,50%),远处转移8例。改变33%(8/24)的患者治疗方案。56例随访病例中30例PET显示阴性,其中5例随访2年后复发,准确率83.4%。26例发现局部和/或多发转移,其中颈部淋巴结转移8例;肺及纵隔转移4例;肝转移7例;腹腔淋巴结转移11例;吻合口局部复发12例,骨转移11例。结论:18FDG-PET对大肠癌的分期和术后的再分期诊断有较高价值。     

18F-FDG PET-CT在非小细胞肺癌术前区域淋巴结分期中的价值

目的 探讨18F-FDG PET-CT在非小细胞肺癌(NSCLC)患者术前区域淋巴结(N)分期方面的价值,以及CT密度和双时相扫描在淋巴结性质判定方面的作用.方法 43例手术病理证实的NSCLC患者均于术前行18F-FDG PET-CT扫描,对常规扫描图像采用PET法(单纯根据18F-FDG摄取水平判断淋巴结性质)和PET+CT密度法(结合CT密度和摄取水平判断淋巴结性质)分析.摄取水平通过目测法和半定量分析法结合判定.双时相扫描的储留指数(RI)>10%为摄取升高.以病理检查作为金标准对所得结果进行分析.结果 以区域淋巴结组为单位,PET法的诊断敏感度、特异度、准确度、阳性预测值和阴性预测值分别为88.0%、88.4%、88.3%、59.5%和97.4%,PET+CT密度法的相应值分别为84.0%、94.6%、92.9%、75.0%和96.8%,其中2种方法的特异度和准确度之间差异有统计学意义(P<0.05).28组淋巴结行双时相扫描,良恶性组摄取变化值(△SUVmax)之间和砒之间差异无统计学意义(P>0.05);在23组延迟相摄取升高的淋巴结中,11组为转移;在5组无摄取升高的淋巴结中,1组为转移.结论 18F-FDG PET-CT在肺癌患者术前N分期方面有较高的诊断价值,结合淋巴结CT密度和18F-FDG摄取水平可进一步提高诊断的特异度和准确度.对于常规相摄取增高的淋巴结,延迟相摄取升高对判断淋巴结性质的价值有限,但无摄取升高则更支持良性诊断.     

Combining independent studies of diagnostic fluorodeoxyglucose positron-emission tomography and computed tomography in mediastinal lymph node staging for non-small cell lung cancer

AIMS AND BACKGROUND: A meta-analysis of diagnostic test performance was conducted to compare the results of relevant studies reporting diagnostic accuracy values for mediastinal staging in patients with non-small cell lung cancer (NSCLC). This paper deals with the two most accurate imaging techniques currently in use: positron emission tomography (PET) with FDG and computed tomography (CT). A statistical pooling method was used to perform a quantitative meta-analysis aimed at demonstrating the potential advantage of one of these two methods. METHODS: Studies in all languages published between 1998 and 2005 that examined the use of FDG-PET and CT for mediastinal staging in NSCLC patients, enrolled at least 18 participants, and provided enough data to allow calculation of sensitivity and specificity rates were considered eligible for the quantitative meta-analysis. Statistical methods to pool the overall estimates of sensitivity and specificity and to compare the discriminant power of PET and CT were discussed and used. RESULTS: Of the 13 studies included in the analysis, 12 reported greater accuracy of FDG-PET than CT in detecting mediastinal lymph node metastases. The sensitivity of FDG-PET ranged from 50% to 100%. The estimate of the overall sensitivity was 0.83% with 95% CI (0.749-0.913). Specificity ranged from 79% to 100%, with an overall estimated specificity of 0.87% with 95% CI (0.80-0.95). For CT, the sensitivity and specificity ranged from 50% to 97% and 58% to 94%, respectively; the overall estimate was 0.68% with 95% CI (0.582-0.788) and 0.76% with 95% CI (0.668-0.859). The summary receiver operating characteristic (SROC) approach was used to assess the superior diagnostic accuracy of one of the two methods. The areas under the two SROC curves were AUC(PET) = 0.909 vs. AUC(CT) = 0.794. CONCLUSIONS: Numerical and visual results of the meta-analysis of recent relevant reports agreed that FDG-PET is more accurate than CT in identifying mediastinal lymph node metastases in non-small cell lung cancer.     

18F-FDG PET/CT在419例肺外科患者中的应用经验

背景与目的我国是肺癌的高发国家,PET/CT在我国的肺外科临床应用价值仍处在探索阶段。本研究总结病理证实的419例肺部肿瘤或肿瘤样病变的患者资料,探讨PET/CT在这一领域的应用价值。方法 2007年12月-2011年8月北京大学肿瘤医院胸外一科单个医疗组对594例肺部肿瘤或肿瘤样病变的患者在诊治过程的不同阶段进行了PET/CT检查,以获得病理的419例患者为研究对象,结合临床、病理及随访,分析PET/CT在良恶性定性,肺癌TNM分期,疗效评价及疗后随访中的应用价值。结果全组419例患者中病理证实为良性者63例,恶性者356例,其中原发性肺癌338例,肺转移瘤18例。PET/CT对恶性肿瘤定性诊断(SUVmax>2.5)的敏感性为85.0%,特异性为52.4%,准确性79.2%,阳性预测值89.2%,阴性预测值42.9%。338例患者中治疗前行PET/CT者275例,共发现远处转移46例(46/275,16.7%),较传统检查(38/275,13.8%)多发现8例。对临床怀疑术后复发者(89例)行PET/CT,发现复发43例(43/89,48.3%),较传统检查(37/89,41.6%)多发现6例。对手术的168例患者作了T及N分期相关性的研究,发现SUVmax与肿瘤直径正相关(P<0.05)。清扫淋巴结共计610组,PET/CT诊断肺癌淋巴结转移的敏感性为36.3%,特异性为93.9%,准确性为84.3%,阳性预测值为54.4%,阴性预测值为88.0%。全组有10例患者化疗前后均作了PET/CT,SUVmax随肿瘤降期而下降,下降平均百分比为37.5%(P<0.05)。结论 PET/CT是现阶段除组织学外另一种可选的判断肺部良恶性病变的方法。PET/CT在肺癌M分期中的作用优于传统检查;也可作为术后复查的常规手段之一。PET/CT对淋巴结转移的诊断特异性较好,但敏感性不高。PET/CT在肺癌化疗评效中有积极意义。     

18F-FDG PET显像在非小细胞肺癌临床分期中的价值

目的 探讨^18F-脱氧葡萄糖-正电子发射体层显像(^18F-FDG PET)在非小细胞肺癌(NscLC)临床分期中的价值。方法 105例NSCLC患者于放射治疗前行^18F-FDG PET检查,进行PET分期,并将PET分期和CT分期结果进行比较分析。结果 ^18F-FDG PET扫描使38例NSCLC患者分期改变,其中分期升级31例,分期降级7例。21例分期升级者PET检查发现了远处转移灶,其治疗方案由根治性治疗改为姑息性治疗;6例分期降级者进行了根治性手术治疗,其中5例PET分期与病理分期一致。PET发现远处转移灶的几率随PET扫描前分期的升级而上升,其中Ⅰ期10．0％(2／20),Ⅱ期14．3％(3／21),Ⅲ期25．0％(16／64)。结论 ^18F-FDG PET显像改变了36．2％(38／105)NSCLC患者的临床分期,影响了其治疗策略。^18F-FDG PET显像对NSCLC患者的临床分期有重要的参考价值。     

鼻咽癌T分期,N分期的研究

鼻咽癌临床分期受Ｔ和Ｎ各种因素的交叉影响，同时也Ｔ与Ｎ之间的相互匹配的不同而发生变化。本文采用单因素生存分析及Ｃｏｘ模型多因素分析方法，分别对完成首程放射治疗的鼻咽癌Ｔ１，Ｔ４Ｎ０Ｍ１３３例及早期ＴＮ０－３Ｍ０２０３例进行分析。