PET-CT in the staging and treatment of non-small-cell lung cancer

Comparison of 68Ga-FAP-2286 and 18F-FDG PET/CT in the diagnosis of advanced lung cancer

Purpose

The 68Ga/177Lu-FAP-2286 is a newly developed tumor imaging agent that shows potential for visualizing and treating tumor stroma. The objective of this research was to evaluate the effectiveness of 68Ga-FAP-2286 PET/CT and 18F-FDG PET/CT in diagnosing advanced lung cancer.

Methods

In this prospective study, patients with lung cancer who underwent 68Ga-FAP-2286 and 18F-FDG PET/CT examinations between September 2022 and June 2023 were analyzed. Lesion uptake was converted to SUVmax. A paired T-test was used to compare the SUVmax, and the number of positive lesions detected by the two methods was recorded.

Results

In total, 31 participants (median age: 56 years) were assessed. The uptake of 68Ga-FAP-2286 was significantly higher than that of 18F-FDG in primary lesions (9.90 ± 5.61 vs. 6.09 ± 2.84, respectively, P < 0.001), lymph nodes (7.95 ± 2.75 vs. 5.55 ± 1.59, respectively, P=0.01), and bone metastases (7.74 ± 3.72 vs. 5.66 ± 3.55, respectively, P=0.04). Furthermore, the detection sensitivity of lymph nodes using 68Ga-FAP-2286 PET/CT was superior to that with 18F-FDG PET/CT [100% (137/137) vs. 78.8% (108/137), respectively], as well as for bone metastases [100% (384/384) vs. 68.5% (263/384), respectively]. However, the detection sensitivity for primary tumors using both modalities was comparable [100% (13/13) for both].

Conclusion

Compared to 18F-FDG PET/CT, 68Ga-FAP-2286 PET/CT demonstrated better lesion detection capabilities for lung cancer, particularly in lymph nodes and bone metastases, providing compelling imaging evidence for the efficacy of 177Lu-FAP-2286 treatment.

Comparison of 68Ga-FAPI and 18F-FDG PET/CT in the Evaluation of Advanced Lung Cancer

Background Gallium 68 (⁶⁸Ga)-labeled fibroblast-activation protein inhibitor (FAPI) has recently been introduced as a promising tumor imaging agent. Purpose To compare ⁶⁸Ga-FAPI PET/CT with fluorine 18 (¹⁸F)-labeled fluorodeoxyglucose (FDG) PET/CT in evaluating lung cancer. Materials and Methods In this prospective study conducted from September 2020 to February 2021, images from participants with lung cancer who underwent both ⁶⁸Ga-FAPI and ¹⁸F-FDG PET/CT examinations were analyzed. The tracer uptakes, quantified by maximum standardized uptake value (SUV_max) and target-to-background ratio (TBR), were compared for paired positive lesions between both modalities using the paired t test or Wilcoxon signed-rank test. Results Thirty-four participants (median age, 64 years [interquartile range: 46-80 years]; 20 men) were evaluated. From visual evaluation, ⁶⁸Ga-FAPI PET/CT and ¹⁸F-FDG PET/CT showed similar performance in the delineation of primary tumors and detection of suspected metastases in the lungs, liver, and adrenal glands. The metabolic tumor volume in primary and recurrent lung tumors showed no difference between modalities (mean: 11.6 vs 10.8, respectively; P = .68). However, compared with ¹⁸F-FDG PET/CT, ⁶⁸Ga-FAPI PET/CT depicted more suspected metastases in lymph nodes (356 vs 320), brain (23 vs 10), bone (109 vs 91), and pleura (66 vs 35). From semiquantitative evaluation, the SUV_max and TBR of primary or recurrent tumors, positive lymph nodes, bone lesions, and pleural lesions at ⁶⁸Ga-FAPI PET/CT were all higher than those at ¹⁸F-FDG PET/CT (all P < .01). Although SUV_max of ⁶⁸Ga-FAPI and ¹⁸F-FDG in brain metastases were not different (mean SUV_max: 9.0 vs 7.4, P = .32), TBR was higher with ⁶⁸Ga-FAPI than with ¹⁸F-FDG (mean: 314.4 vs 1.0, P = .02). Conclusion Gallium 68-labeled fibroblast-activation protein inhibitor PET/CT may outperform fluorine 18-labeled fluorodeoxyglucose PET/CT in staging lung cancer, particularly in the detection of metastasis to the brain, lymph nodes, bone, and pleura. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Jacobson and Van den Abbeele in this issue.

The prognostic value of tumor/lymph node standardized uptake value max ratio and correlation with hematologic parameters in stage III nonsmall cell lung cancer

Stage III non-small cell lung cancer (NSCLC) is a highly heterogeneous subtype of lung cancer. There are still no widely accepted prognostic parameters for stage III NSCLC. In this study, we evaluated the prognostic value of the standardized uptake value (SUV) max ratio of primary tumor to lymph node (T/N SUV max) and its correlation with various hematological parameters.Patient data were reviewed from the hospital database retrospectively. The T/N SUV max ratio was calculated by dividing the SUV max of the primary tumor by the maximal SUV max of the lymph node. The cut-off value for T/N SUV max ratio was determined by receiver operating characteristic analysis. Survival analysis was performed by Kaplan-Meier method with the Long-rank test. P value < .05 was considered statistically significant.A total of 52 patients were included in this study. The optimal cut-off value for T/N SUV max was 1.96 (area under the curve: 0.74; 72.7% sensitivity and 73.7% specificity). Patients with T/N SUV max ≤1.96 were defined as high risk patients and those with >1.96 were defined as low risk patients. The median event (recurrence or progression) free survival was 24.3 months (95% confidence interval: 12.0-36.6) for low risk patients, and 9.2 months (95% confidence interval: 6.1-12.4) for high risk patients (P = .0015). There was an inverse correlation between T/N SUV max and hemoglobin concentration and mean corpuscular volume (rho: -0.349, P = .011; rho: -0.312, P = .025, respectively).Low risk patients had a more favorable prognosis compared to high risk patients. We demonstrated that T/N SUV max can be of prognostic value in stage III NSCLC. T/N SUV max correlated only with hemoglobin and mean corpuscular volume.

The added value of18F-FDG PET/CT in staging non-small cell lung cancer

Background

Non-small cell lung cancer (NSCLC) accounts for about 80% of all lung cancers. The current criteria for its staging are based on the TNM system that determines treatment options and predicts survival rate in patients. The aim of the study was to evaluate the diagnostic accuracy of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography PET/CT in staging of NSCLC patients.

Methods

A retrospective study was conducted. We reviewed the CT and PET/CT examinations done in our institution on pathologically proven patients of NSCLC, in the period between October 2018 and end of July 2019.

Results

A total of 40 patients were evaluated with the age ranging from 37 to 77 years old, and the mean was 55.63 years (SD ± 10.29). There were 31 male cases and 9 female cases. When we compared contrast enhanced CT (CECT) to PET-CT for staging, PET-CT helped upstage disease in 10 of 40 patients (25%) and downstage in 3 of 40 patients (7.5%).

Conclusion

PET/CT is a useful imaging tool in initial staging of the newly diagnosed patients with NSCLC. It is better thаn СT alone fоr detection of malignant lesions for accurate staging. It can change the strategy of treatment according to its findings.

Validation of the 8th TNM classification for small-cell lung cancer in a retrospective material from Sweden

BACKGROUND

The purpose of this study was to evaluate on a Swedish cohort of small cell lung cancer (SCLC) patients whether the 8th TNM staging system can provide additional prognostic information in comparison with the previous 6th and 7th TNM versions and the older 2-stage LD vs ED system.

METHODS

We reviewed the medical records of patients (pts) with SCLC diagnosed between January 2008 and February 2016 in the Stockholm and Gotland region. Each patient file was revised and reclassified from the VASGL system to the 6^th, 7^th and 8^th TNM system respectively. We assessed overall survival (OS) according to the T, N, M-descriptor and compared LD/ED with the 6^th, -7^th, -8^th editions of TNM. Four separate multivariate models adjusted for basic patient characteristics were performed.

RESULTS

In total, 706 pts were eligible for the study. Median OS was 7.7 months. Differences in survival between less advanced stages (IA-IIB) were difficult to assess since there were few patients (n = 32). The majority of patients (78%) migrated to new stage categories in the 8th TNM edition; IIIC, IVA and IVB. In the 8th TNM edition subjects with M1a disease had a similar prognosis to patients with multiple metastatic diseases, M1c. Conversely, subjects with a single metastasis had a similar prognosis to M0-disease. On multivariate analysis, stage was an independent prognostic factor independently of the classification system used.

CONCLUSION

In this cohort, the 8th TNM classification system seems to provide more accurate prognostic information in patients with SCLC when compared to the previous TNM versions. There were few cases with Stages I and II and therefore no robust conclusions can be drawn in this category. The reason single metastatic lesions (M1b) had a better prognosis when compared to M1c could be due to a more aggressive treatment approach in these patients.

Current role of standardized uptake valuemax-derived ratios in N2 fluorine-18 fluorodeoxyglucose positron-emission tomography non-small cell lung cancer

Mediastinal staging is a crucial moment in management of non-small cell lung cancer (NSCLC) patients. In integrated pathways, 18-fluorine fluorodeoxyglucose positron-emission tomography (¹⁸F-FDG-PET/CT) is an indispensable imaging resource with its peculiarities and its limitations. A critical review of work up protocols would certainly help to standardize procedures with important reflections also on the diagnostic value of this examination. In this regard, new semi-quantitative and semi-qualitative indexes have been proposed with the aim of increasing the accuracy of ¹⁸F-FDG-PET/CT in mediastinal lymph node staging. These latter, such as SUV_n/t and SUV indexes, seem to overcome the problem of spatial resolution and discrimination of malignancy by endorsing a new predictive and prognostic role.

Ratio of lymph node to primary tumor SUVmax multiplied by maximal tumor diameter on positron emission tomography/integrated computed tomography may be a predictor of mediastinal lymph node malignancy in lung cancer

Positron emission tomography/integrated computed tomography (PET/CT) provides the most accurate imaging modality for preoperative lung cancer staging. However, the diagnostic accuracy of maximum standardized uptake value (SUVmax) for mediastinal (N2) lymph nodes (LN) is unclear. We compared SUVmax, the ratio of LN to primary tumor SUVmax (SUVn/t), and SUVn/t multiplied by maximal tumor diameter (SUVindex) in terms of their abilities to predict mediastinal LN malignancy.We retrospectively analyzed 170 mediastinal LN stations from 73 consecutive patients who underwent systemic LN resection and PET/CT within 27 days. The SUVmax of the primary tumors was >2.0 and the SUVmax of the mediastinal LN stations ranged from 2.0 to 7.0 on PET/CT. Receiver-operating characteristic curves (ROCs) of SUVmax, SUVn/t, and SUVindex were calculated separately and the areas under the curves (AUCs) were used to assess the abilities of the parameters to predict LN malignancy. The optimal cutoff values were calculated from each ROC curve and the diagnostic abilities were also compared. The diagnostic accuracies of the 3 methods were also assessed separately in smoking and nonsmoking patients.Twenty-eight LN stations were malignancy-positive and the remaining 142 were malignancy-negative. The AUCs for SUVindex, SUVn/t, and SUVmax were 0.709, 0.590, and 0.673, respectively, and the optimal cutoff values for SUVindex, SUVn/t, and SUVmax were 1.11, 0.34, and 3.6, respectively. The differences between SUVindex and SUVn/t were significant, but there was no significant difference between SUVindex and SUVmax. There were no significant differences between smokers and nonsmokers in the AUCs for any of the methods for predicting LN malignancy (P values >0.05).SUVindex may be a predictor of mediastinal LN malignancy in lung cancer patients.

Ratio of Lymph Node to Primary Tumor SUV on PET/CT Accurately Predicts Nodal Malignancy in Non-Small-Cell Lung Cancer

Thoracic lymph nodes with marginally elevated maximum standardized uptake value (SUVmax) on PET/CT a diagnostic challenge in staging non-small-cell lung cancer. We evaluated the ratio of lymph node to primary tumor SUVmax (SUVN/T) in predicting nodal malignancy among 132 sampled nodes from 85 patients both a primary tumor SUVmax > 2.5 and LN SUVmax 2.0 to 6.0. SUVN/T was more accurate than SUVmax for this subset of patients.

INTRODUCTION/BACKGROUND

Among non-small-cell lung cancers with appreciable functional activity, positron emission tomography/computed tomography (PET/CT) is the most accurate imaging modality for clinical staging. However, lymph nodes (LN) with marginally elevated standardized uptake value (SUV) present a diagnostic challenge. In this retrospective study, we hypothesized that normalizing the LN SUV by using the ratio of the LN to primary tumor SUVmax (SUVN/T) may be a better predictor of nodal malignancy than using SUVmax alone for nodes with low to intermediate SUV.

PATIENTS AND METHODS

We identified 172 patients with newly diagnosed non-small-cell lung cancer who underwent pathologic LN staging and PET/CT within 31 days before biopsy. Receiver operating characteristic curves with area under the curve (AUC) calculations were used to evaluate SUVmax and SUVN/T for their ability to predict nodal malignancy for both the entire cohort of 504 LNs and a subset of 132 LNs from 85 patients who had both primary tumor SUVmax > 2.5 and LN SUVmax 2.0 to 6.0.

RESULTS

In patients with primary tumor SUVmax > 2.5 and LN SUVmax 2.0 to 6.0, SUVN/T was significantly more accurate in predicting nodal malignancy (AUC, 0.846; 95% confidence interval, 0.775-0.917) than SUVmax (AUC, 0.653; 95% confidence interval, 0.548-0.759). The optimal cutoff value of SUVN/T to predict nodal malignancy was 0.28 (90% sensitivity, 68% specificity). Sensitivity was > 95% for SUVN/T < 0.21, whereas specificity was > 95% for SUVN/T > 0.50.

CONCLUSION

The ratio of LN SUV to primary tumor SUV on PET/CT is more accurate than SUVmax when assessing nodes of low to intermediate SUV.

PET imaging of neovascularization with (68)Ga-3PRGD2 for assessing tumor early response to Endostar antiangiogenic therapy

Antiangiogenic therapy is an effective strategy to inhibit tumor growth. Endostar, as an approved antiangiogenesis agent, inhibits the newborn vascular endothelial cells, causing the decrease of integrin αvβ3 expression. Radiolabeled 3PRGD2, a novel PEGlayted RGD dimer probe (PEG4-E[PEG4-c(RGDfK)]2) showed highly specific targeting capability to integrin αvβ3, which could be used for monitoring the efficacy of Endostar antiangiogenic therapy. In this study, (68)Ga-3PRGD2 PET imaging was performed in Endostar treated/untreated Lewis Lung Carcinoma (LLC) mice on days 3, 7, 14, and 21 post-treatment for monitoring the tumor response to Endostar treatment, with the (18)F-FDG imaging as control. As a result, (68)Ga-3PRGD2 PET reflected the tumor response to Endostar antiangiogenic therapy much earlier (day 3 post-treatment vs day 14 post-treatment) and more accurately than that of (18)F-FDG metabolic imaging, which provides new opportunities to develop individualized therapeutic approaches, establish optimized dosages and dose intervals for effective treatment that improve the survival rate of patients.

The Anatomical Biological Value on Pretreatment (18)F-fluorodeoxyglucose Positron Emission Tomography Computed Tomography Predicts Response and Survival in Locally Advanced Head and Neck Cancer

¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) has become increasingly relevant in the staging of head and neck cancers, but its prognostic value is controversial. The objective of this study was to evaluate different PET/CT parameters for their ability to predict response to therapy and survival in patients treated for head and neck cancer. A total of 28 consecutive patients with a variety of newly diagnosed head and neck cancers underwent PET/CT scanning at our institution before initiating definitive radiation therapy. All underwent a posttreatment PET/CT to gauge tumor response. Pretreatment PET/CT parameters calculated include the standardized uptake value (SUV) and the anatomical biological value (ABV), which is the product of SUV and greatest tumor diameter. Maximum and mean values were studied for both SUV and ABV, and correlated with response rate and survival. The mean pretreatment tumor ABV_max decreased from 35.5 to 7.9 (P = 0.0001). Of the parameters tested, only pretreatment ABV_max was significantly different among those patients with a complete response (CR) and incomplete response (22.8 vs. 65, respectively, P = 0.021). This difference was maximized at a cut-off ABV_max of 30 and those patients with ABV_max < 30 were significantly more likely to have a CR compared to those with ABV_max of ≥ 30 (93.8% vs. 50%, respectively, P = 0.023). The 5-year overall survival was 80% compared to 36%, respectively, (P = 0.028). Multivariate analysis confirmed that ABV_max was an independent prognostic factor. Our data supports the use of PET/CT, and specifically ABV_max, as a prognostic factor in head and neck cancer. Patients who have an ABV_max ≥ 30 were more likely to have a poor outcome with chemoradiation alone, and a more aggressive trimodality approach may be indicated in these patients.

Initial experience of MR/PET in a clinical cancer center

Magentic Resonance/positron emission tomography (PET) has been introduced recently for imaging of clinical patients. This hybrid imaging technology combines the inherent strengths of MRI with its high soft-tissue contrast and biological sequences with the inherent strengths of PET, enabling imaging of metabolism with a high sensitivity. In this article, we describe the initial experience of MR/PET in a clinical cancer center along with a review of the literature. For establishing MR/PET in a clinical setting, technical challenges, such as attenuation correction and organizational challenges, such as workflow and reimbursement, have to be overcome. The most promising initial results of MR/PET have been achieved in anatomical areas where high soft-tissue and contrast resolution is of benefit. Head and neck cancer and pelvic imaging are potential applications of this hybrid imaging technology. In the pediatric population, MR/PET can decrease the lifetime radiation dose. MR/PET protocols tailored to different types of malignancies need to be developed. After the initial exploration phase, large multicenter trials are warranted to determine clinical indications for this exciting hybrid imaging technology and thereby opening new horizons in molecular imaging.

The correlation of SUVmax with pathological characteristics of primary tumor and the value of Tumor/ Lymph node SUVmax ratio for predicting metastasis to lymph nodes in resected NSCLC patients

Background

We aimed to investigate the correlation of maximum standardized uptake value (SUVmax) with pathological characteristics of primary tumor and to determine a Tumor/ Lymph node (T/LN) SUVmax ratio predicting metastasis to lymph nodes in NSCLC patients.

Methods

Eighty-one NSCLC patients who had PET/CT examination at initial staging and subsequently underwent surgical resection were retrospectively evaluated. There were 100 PET/CT positive mediastinal or hilar lymph node stations. Pathological characteristics of the tumor such as largest tumor diameter, tumor histology, differentiation, number of mitosis, degree of stromal inflammation, necrosis; etiology of PET/CT positive lymph node stations; SUVmax of primary tumor and positive lymph node stations were recorded. A T/LN SUVmax ratio was calculated for each lymph node station.

Results

SUVmax of the primary tumor was positively correlated with the largest tumor diameter (p = 0.001, r = 0.374), number of mitosis (p < 0.001, r = 0.405), and postoperative pathological stage (p = 0.007, r = 0.298). Patients with squamous cell carcinoma had a statistically significant higher mean SUVmax, number of mitosis and advanced N stages compared to adenocarcinoma. The etiology of 100 PET/CT positive lymph node stations were metastasis in 14, anthracosis in 40, reactive in 39, granulomatous in 4, and silicosis in 3 patients. A T/LN SUVmax ratio of 5 or lower was suggestive for a malignant lymph node with a sensitivity of 92.8% and specificity of 47%.

Conclusions

SUVmax of a primary tumor is related to certain pathological characteristics, such as largest diameter, histology, and number of mitosis. A T/LN SUVmax ratio lower than 5 predicts the metastasis to lymph nodes with a high sensitivity.

Pulmonary lesion assessment: comparison of whole-body hybrid MR/PET and PET/CT imaging--pilot study

PURPOSE

To compare the performance of magnetic resonance (MR)/positron emission tomography (PET) imaging in the staging of lung cancer with that of PET/computed tomography (CT) as the reference standard and to compare the quantification accuracy of a new whole-body MR/PET system with corresponding PET/CT data sets.

MATERIALS AND METHODS

Institutional review board approval and informed consent were obtained. Ten patients in whom bronchial carcinoma was proven or clinically suspected underwent clinically indicated fluorine 18 fluorodeoxyglucose (FDG) PET/CT and, immediately thereafter, whole-body MR/PET imaging with a new hybrid whole-body system (3.0-T MR imager with integrated PET system). Attenuation correction of MR/PET images was segmentation based with fat-water separation. Tumor-to-liver ratios were calculated and compared between PET/CT and MR/PET imaging. Tumor staging on the basis of the PET/CT and MR/PET studies was performed by two readers. Spearman rank correlation was used for comparison of data.

RESULTS

MR/PET imaging provided diagnostic image quality in all patients, with good tumor delineation. Most lesions (nine of 10) showed pronounced FDG uptake. One lesion was morphologically suspicious for malignancy at CT and MR imaging but showed no FDG uptake. MR/PET imaging had higher mean tumor-to-liver ratios than did PET/CT (4.4 ± 2.0 [standard deviation] for PET/CT vs 8.0 ± 3.9 for MR/PET imaging). Significant correlation regarding the tumor-to-liver ratio was found between both imaging units (ρ = 0.93; P < .001). Identical TNM scores based on MR/PET and PET/CT data were found in seven of 10 patients. Differences in T and/or N staging occurred mainly owing to modality-inherent differences in lesion size measurement.

CONCLUSION

MR/PET imaging of the lung is feasible and provides diagnostic image quality in the assessment of pulmonary masses. Similar lesion characterization and tumor stage were found in comparing PET/CT and MR/PET images in most patients.

99mTc-labeled RGD-BBN peptide for small-animal SPECT/CT of lung carcinoma

We recently designed and synthesized a Glu-c(RGDyK)-bombesin (RGD-BBN) heterodimeric peptide exhibiting a dual integrin α(v)β(3) and gastrin-releasing peptide receptor (GRPR) targeting property. In this study, we investigated whether (99m)Tc-labeled RGD-BBN peptide could be used for the noninvasive detection of lung carcinoma by using small-animal single-photon emission computed tomography (SPECT)/CT. RGD-BBN peptide was conjugated with 6-hydrazinonicotinyl (HYNIC) and then radiolabeled with (99m)Tc using tricine and TPPTS as the coligands (TPPTS = trisodium triphenylphosphine-3,3',3"-trisulfonate). The biodistribution, planar gamma imaging, and small-animal SPECT/CT studies of (99m)Tc-HYNIC(tricine)(TPPTS)-RGD-BBN ((99m)Tc-RGD-BBN) were performed in C57/BL6 mice bearing Lewis lung carcinoma (LLC) or bearing both inflammation and LLC. HYNIC-RGD-BBN possessed a dual integrin α(v)β(3) and GRPR binding capacity. (99m)Tc-RGD-BBN was prepared with a high radiochemical purity (>98%), and it exhibited specific tumor imaging with high contrast to the contralateral background. (99m)Tc-RGD-BBN was superior to (18)F-FDG for distinguishing lung carcinoma from inflammation. The uptake of (99m)Tc-RGD-BBN in LLC xenografts was 2.69 ± 0.66% ID/g at 1 h postinjection (p.i.) and was decreased to 1.99 ± 0.61% ID/g at 2 h p.i. The inflammation uptake of (99m)Tc-RGD-BBN was 1.20 ± 0.32% ID/g at 1 h and 0.56 ± 0.17% ID/g at 2 h p.i., respectively. High pancreas uptake (25.76 ± 5.49%ID/g and 19.56 ± 6.78% ID/g at 1 and 2 h p.i., respectively) was also found due to the high GRPR expression of this organ. Small-animal SPECT/CT using (99m)Tc-RGD-BBN can specifically detect the LLC pulmonary metastases. Our results suggested that SPECT/CT with (99m)Tc-RGD-BBN would provide an effective approach for the noninvasive detection of lung cancer.

[Application of ¹⁸F-FDG PET/CT in pulmonary disease: a report of 419 cases]

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。