Advances in positron emission tomography technology have increased the need for surgical staging in non–small cell lung cancer

Combination of 18F-FDG PET/CT and convex probe endobronchial ultrasound elastography for intrathoracic malignant and benign lymph nodes prediction

Background

Positron emission tomography–computed tomography (PET/CT) and convex probe endobronchial ultrasound (CP-EBUS) elastography are important diagnostic methods in predicting intrathoracic lymph nodes (LNs) metastasis, but a joint analysis of the two examinations is still lacking. This study aimed to compare the diagnostic efficiency of the two methods and explore whether the combination can improve the diagnostic efficiency in differentiating intrathoracic benign LNs from malignant LNs.

Materials and Methods

LNs examined by EBUS-guided transbronchial needle aspiration (EBUS-TBNA) and PET/CT from March 2018 to June 2019 in Shanghai Chest Hospital were retrospectively analyzed as the model group. Four PET/CT parameters, namely, maximal standardized uptake value mean standardized uptake value (SUVmean), SUVmean, metabolic tumor volume (MTV), and tumor lesion glycolysis (TLG); four quantitative elastography indicators (stiff area ratio, mean hue value, RGB, and mean gray value); and the elastography grading score of targeted LNs were analyzed. A prediction model was constructed subsequently and the dataset from July to November 2019 was used to validate the diagnostic capability of the model.

Results

A total of 154 LNs from 135 patients and 53 LNs from 47 patients were enrolled in the model and validation groups, respectively. Mean hue value and grading score were independent malignancy predictors of elastography, as well as SUVmax and TLG of PET/CT. In model and validation groups, the combination of PET/CT and elastography demonstrated sensitivity, specificity, positive and negative predictive values, and accuracy for malignant LNs diagnosis of 85.87%, 88.71%, 91.86%, 80.88%, and 87.01%, and 94.44%, 76.47%, 89.47%, 86.67%, and 88.68%, respectively. Moreover, elastography had better diagnostic accuracies than PET/CT in both model and validation groups (85.71% vs. 79.22%, 86.79% vs. 75.47%).

Conclusion

EBUS elastography demonstrated better efficiency than PET/CT and the combination of the two methods had the best diagnostic efficacy in differentiating intrathoracic benign from malignant LNs, which may be helpful for clinical application.

A PET/CT nomogram incorporating SUVmax and CT radiomics for preoperative nodal staging in non-small cell lung cancer

Objectives

To develop and validate a PET/CT nomogram for preoperative estimation of lymph node (LN) staging in patients with non-small cell lung cancer (NSCLC).

Methods

A total of 263 pathologically confirmed LNs from 124 patients with NCSLC were retrospectively analyzed. Positron-emission tomography/computed tomography (PET/CT) examination was performed before treatment according to the clinical schedule. In the training cohort (N = 185), malignancy-related features, such as SUVmax, short-axis diameter (SAD), and CT radiomics features, were extracted from the regions of LN based on the PET/CT scan. The Minimum-Redundancy Maximum-Relevance (mRMR) algorithm and the Least Absolute Shrinkage and Selection Operator (LASSO) regression model were used for feature selection and radiomics score building. The radiomics score (Rad-Score) and SUVmax were incorporated in a PET/CT nomogram using the multivariable logistic regression analysis. The performance of the proposed model was evaluated with discrimination, calibration, and clinical application in an independent testing cohort (N = 78).

Results

The radiomics scores consisting of 14 selected features were significantly associated with LN status for both training cohort with AUC of 0.849 (95% confidence interval (CI), 0.796–0.903) and testing cohort with AUC of 0.828 (95% CI, 0.782–0.919). The PET/CT nomogram incorporating radiomics score and SUVmax showed moderate improvement of the efficiency with AUC of 0.881 (95% CI, 0.834–0.928) in the training cohort and AUC of 0.872 (95% CI, 0.797–0.946) in the testing cohort. The decision curve analysis indicated that the PET/CT nomogram was clinically useful.

Conclusion

The PET/CT nomogram, which incorporates Rad-Score and SUVmax, can improve the diagnostic performance of LN metastasis.

Key Points

• The PET/CT nomogram (Int-Score) based on lymph node (LN) PET/CT images can reliably predict LN status in NSCLC.

• Int-Score is a relatively objective diagnostic method, which can play an auxiliary role in the process of clinicians making treatment decisions.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-020-07624-9.

Impact of EBUS-TBNA in addition to [18F]FDG-PET/CT imaging on target volume definition for radiochemotherapy in stage III NSCLC

Purpose/introduction

[¹⁸F]FDG-PET/CT is the standard imaging-technique for radiation treatment (RT) planning in locally advanced non-small cell lung cancer (NSCLC). The purpose of this study was to examine the additional value of endobronchial-ultrasound transbronchial needle aspiration (EBUS-TBNA) to standard PET/CT for mediastinal lymph-node (LN) staging and its impact on clinical target volume (CTV).

Materials and methods

All consecutive patients with primary stage III NSCLC who underwent [¹⁸F]FDG-PET/CT and EBUS-TBNA prior to RT were analyzed from 12/2011 to 06/2018. LN-stations were assessed by an expert-radiologist and a nuclear medicine-physician. CTV was evaluated by two independent radiation oncologists. LNs were grouped with increasing distance along the lymphatic chains from primary tumor into echelon-1 (ipsilateral hilum), echelon-2 (LN-station 7 and ipsilateral 4), and echelon-3 (remaining mediastinum and contralateral hilum).

Results

A total of 675 LN-stations of which 291 were positive for tumor-cells, were sampled by EBUS-TBNA in 180 patients. The rate of EBUS-positive LNs was 43% among all sampled LNs. EBUS-positivity in EBUS-probed LNs decreased from 85.8% in echelon-1 LNs to 42.4%/ 9.6% in echelon-2/ -3 LNs, respectively (p < 0.0001, Fisher’s exact test). The false discovery rate of PET in comparison with EBUS results rose from 5.3% in echelon-1 to 32.9%/ 69.1% in echelon-2/ -3 LNs, respectively (p < 0.0001, Fisher’s exact test). Sensitivity and specificity of FDG-PET/CT ranged from 85 to 99% and 67 to 80% for the different echelons. In 22.2% patients, EBUS-TBNA finding triggered changes of the treated CTV, compared with contouring algorithms based on FDG-avidity as the sole criterion for inclusion. CTV was enlarged in 6.7% patients due to EBUS-positivity in PET-negative LN-station and reduced in 15.5% by exclusion of an EBUS-negative but PET-positive LN-station.

Conclusion

The false discovery rate of [¹⁸F]FDG-PET/CT increased markedly with distance from the primary tumor. Inclusion of systematic mediastinal LN mapping by EBUS-TBNA in addition to PET/CT has the potential to increase accuracy of target volume definition, particularly in echelon-3 LNs. EBUS-TBNA is recommended as integral part of staging for radiochemotherapy in stage III NSCLC.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-021-05204-7.

Accuracy of lung cancer staging in the multidisciplinary team setting

Accurate staging of lung cancer is of utmost importance in determining the stage-appropriate treatment and prognosis. Imaging tests which include contrast-enhanced computed tomography (CT) examination of the chest to include the liver and adrenal glands and 18-fluoro-2 deoxyglucose positron emission tomography (PET)/CT scan facilitate the initial tumor node metastasis (TNM) staging of the disease and provide guidance on the optimal biopsy site and biopsy method. The diagnostic and staging approach should be tailored to the individual patient according to risk, benefit, patient preferences, and available expertise. Diagnosis and staging should preferably be accomplished with a single procedure or the least number of invasive procedures if more than one is needed. Ideally, centers managing lung cancer patients should have a multidisciplinary thoracic oncology board prescribing personalized evidence-based management tailored to each individual patient. Multidisciplinary team (MDT) meetings provide a platform for key experts from various disciplines to contribute specific advice on the management of each individual patient. As assessment of mediastinal lymph node involvement is an important component of lung cancer staging, optimal mediastinal staging can be achieved with a variety of techniques that can be discussed and performed by the various specialists in the MDT. Despite a relative paucity of quality evidence that MDT contributes to improvements in lung cancer survival outcomes, this approach has evolved to become the standard of care in many centers around the world. Thoracic MDT has resulted in more focused and timely investigations for histopathologic diagnosis and disease staging which translate into earlier treatment initiation. Moreover, there is increasing evidence that MDT care facilitates and allows access to investigations that lead to improved accuracy of tumor and nodal staging. However, there is still a paucity of evidence on the accuracy of lung cancer staging in the MDT setting.

Mediastinal lymph node staging for lung cancer

Mediastinal lymph node staging is crucial in deciding the treatment strategy for lung carcinoma. The diagnosis rate of computed tomography is not high; however, it is a standard examination. Although the contrast computed tomography is necessary for an accurate diagnosis, images from the positron emission tomography are excellent, and these two technologies are independent and complementary. Positron emission tomography has a disadvantage of false positives and false negatives, but it should also be used in cases where lymph node diameters are 1 cm or more. However, image-based diagnostic methods are not an alternative to histological examination. The results of a transbronchial needle biopsy are extremely dependent on the inspection method, the diagnostic ability of the physician, and the staging of the case. The transesophageal ultrasound endoscope is useful for reaching parts inaccessible by a mediastinoscope. Although its employment requires technical training, it is becoming popular as a minimally invasive method of obtaining cell and the tissue samples. A thoracoscopic biopsy is considered as a last resort for mediastinal lymph node diagnosis. Carefully-chosen invasive procedures are necessary to diagnose swollen lymph nodes. Although mediastinoscopy is still considered as the gold standard, most procedures will be replaced by a comparatively minimally invasive method in the future.

Texture Analysis and Synthesis of Malignant and Benign Mediastinal Lymph Nodes in Patients with Lung Cancer on Computed Tomography

Texture analysis of computed tomography (CT) imaging has been found useful to distinguish subtle differences, which are in- visible to human eyes, between malignant and benign tissues in cancer patients. This study implemented two complementary methods of texture analysis, known as the gray-level co-occurrence matrix (GLCM) and the experimental semivariogram (SV) with an aim to improve the predictive value of evaluating mediastinal lymph nodes in lung cancer. The GLCM was explored with the use of a rich set of its derived features, whereas the SV feature was extracted on real and synthesized CT samples of benign and malignant lymph nodes. A distinct advantage of the computer methodology presented herein is the alleviation of the need for an automated precise segmentation of the lymph nodes. Using the logistic regression model, a sensitivity of 75%, specificity of 90%, and area under curve of 0.89 were obtained in the test population. A tenfold cross-validation of 70% accuracy of classifying between benign and malignant lymph nodes was obtained using the support vector machines as a pattern classifier. These results are higher than those recently reported in literature with similar studies.

The Role of Fluorodeoxy-D-glucose Positron Emission Tomography/Computed Tomography in Nodal Staging of Nonsmall Cell Lung Cancer in Sequential Surgical Algorithm

With nonsmall cell lung cancer (NSCLC), accurate mediastinal nodal staging is crucial to determine whether a patient is or is not a surgical candidate. Traditionally, computed tomography (CT) and fluorodeoxy-D-glucose (FDG) positron emission tomography (PET)/CT are the initial steps followed by tissue sampling through mediastinoscopy and/or thoracotomy, which are invasive procedures. There is controversy regarding the possibility of omission of the invasive diagnostic procedures and solely relying on noninvasive presurgical staging CT and FDG PET/CT results. Eighty-three patients who had PET/CT, mediastinoscopy, and thoracotomy for NSCLC were analyzed. For all lymph nodes that may be sampled by mediastinoscopy, PET/CT sensitivity was 80%, specificity was 86%, positive predictive value was 47%, and negative predictive value (NPV) was 97%; and for those in this group whose clinical stage was T1/T2 M0, sensitivity was 100% and specificity was 84%. For lymph nodes accessible only at thoracotomy, sensitivity was 42% and specificity was 88%. FDG PET/CT is accurate in assessing stations 2R/L, 4R/L, and 7 nodes and has the potential to replace mediastinoscopy in the treatment algorithm of T1/T2 M0 disease. A negative PET/CT may potentially prevent the patient from invasive mediastinoscopy given its high NPV. However, a patient with positive PET/CT should undergo tissue biopsy with pathology confirmation.

PET-CT for assessing mediastinal lymph node involvement in patients with suspected resectable non-small cell lung cancer

BACKGROUND

A major determinant of treatment offered to patients with non-small cell lung cancer (NSCLC) is their intrathoracic (mediastinal) nodal status. If the disease has not spread to the ipsilateral mediastinal nodes, subcarinal (N2) nodes, or both, and the patient is otherwise considered fit for surgery, resection is often the treatment of choice. Planning the optimal treatment is therefore critically dependent on accurate staging of the disease. PET-CT (positron emission tomography-computed tomography) is a non-invasive staging method of the mediastinum, which is increasingly available and used by lung cancer multidisciplinary teams. Although the non-invasive nature of PET-CT constitutes one of its major advantages, PET-CT may be suboptimal in detecting malignancy in normal-sized lymph nodes and in ruling out malignancy in patients with coexisting inflammatory or infectious diseases.

OBJECTIVES

To determine the diagnostic accuracy of integrated PET-CT for mediastinal staging of patients with suspected or confirmed NSCLC that is potentially suitable for treatment with curative intent.

SEARCH METHODS

We searched the following databases up to 30 April 2013: The Cochrane Library, MEDLINE via OvidSP (from 1946), Embase via OvidSP (from 1974), PreMEDLINE via OvidSP, OpenGrey, ProQuest Dissertations & Theses, and the trials register www.clinicaltrials.gov. There were no language or publication status restrictions on the search. We also contacted researchers in the field, checked reference lists, and conducted citation searches (with an end-date of 9 July 2013) of relevant studies.

SELECTION CRITERIA

Prospective or retrospective cross-sectional studies that assessed the diagnostic accuracy of integrated PET-CT for diagnosing N2 disease in patients with suspected resectable NSCLC. The studies must have used pathology as the reference standard and reported participants as the unit of analysis.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data pertaining to the study characteristics and the number of true and false positives and true and false negatives for the index test, and they independently assessed the quality of the included studies using QUADAS-2. We calculated sensitivity and specificity with 95% confidence intervals (CI) for each study and performed two main analyses based on the criteria for test positivity employed: Activity > background or SUVmax ≥ 2.5 (SUVmax = maximum standardised uptake value), where we fitted a summary receiver operating characteristic (ROC) curve using a hierarchical summary ROC (HSROC) model for each subset of studies. We identified the average operating point on the SROC curve and computed the average sensitivities and specificities. We checked for heterogeneity and examined the robustness of the meta-analyses through sensitivity analyses.

MAIN RESULTS

We included 45 studies, and based on the criteria for PET-CT positivity, we categorised the included studies into three groups: Activity > background (18 studies, N = 2823, prevalence of N2 and N3 nodes = 679/2328), SUVmax ≥ 2.5 (12 studies, N = 1656, prevalence of N2 and N3 nodes = 465/1656), and Other/mixed (15 studies, N = 1616, prevalence of N2 to N3 nodes = 400/1616). None of the studies reported (any) adverse events. Under-reporting generally hampered the quality assessment of the studies, and in 30/45 studies, the applicability of the study populations was of high or unclear concern.The summary sensitivity and specificity estimates for the 'Activity > background PET-CT positivity criterion were 77.4% (95% CI 65.3 to 86.1) and 90.1% (95% CI 85.3 to 93.5), respectively, but the accuracy estimates of these studies in ROC space showed a wide prediction region. This indicated high between-study heterogeneity and a relatively large 95% confidence region around the summary value of sensitivity and specificity, denoting a lack of precision. Sensitivity analyses suggested that the overall estimate of sensitivity was especially susceptible to selection bias; reference standard bias; clear definition of test positivity; and to a lesser extent, index test bias and commercial funding bias, with lower combined estimates of sensitivity observed for all the low 'Risk of bias' studies compared with the full analysis.The summary sensitivity and specificity estimates for the SUVmax ≥ 2.5 PET-CT positivity criterion were 81.3% (95% CI 70.2 to 88.9) and 79.4% (95% CI 70 to 86.5), respectively.In this group, the accuracy estimates of these studies in ROC space also showed a very wide prediction region. This indicated very high between-study heterogeneity, and there was a relatively large 95% confidence region around the summary value of sensitivity and specificity, denoting a clear lack of precision. Sensitivity analyses suggested that both overall accuracy estimates were marginally sensitive to flow and timing bias and commercial funding bias, which both lead to slightly lower estimates of sensitivity and specificity.Heterogeneity analyses showed that the accuracy estimates were significantly influenced by country of study origin, percentage of participants with adenocarcinoma, (¹⁸F)-2-fluoro-deoxy-D-glucose (FDG) dose, type of PET-CT scanner, and study size, but not by study design, consecutive recruitment, attenuation correction, year of publication, or tuberculosis incidence rate per 100,000 population.

AUTHORS' CONCLUSIONS

This review has shown that accuracy of PET-CT is insufficient to allow management based on PET-CT alone. The findings therefore support National Institute for Health and Care (formally 'clinical') Excellence (NICE) guidance on this topic, where PET-CT is used to guide clinicians in the next step: either a biopsy or where negative and nodes are small, directly to surgery. The apparent difference between the two main makes of PET-CT scanner is important and may influence the treatment decision in some circumstances. The differences in PET-CT accuracy estimates between scanner makes, NSCLC subtypes, FDG dose, and country of study origin, along with the general variability of results, suggest that all large centres should actively monitor their accuracy. This is so that they can make reliable decisions based on their own results and identify the populations in which PET-CT is of most use or potentially little value.

A pilot study of 4'-[methyl-11C]-thiothymidine PET/CT for detection of regional lymph node metastasis in non-small cell lung cancer

Background

4′-[methyl-¹¹C]-thiothymidine (4DST) is a novel positron emission tomography (PET) tracer to assess proliferation of malignancy. The diagnostic abilities of 4DST and 2-deoxy-2-¹⁸ F-fluoro-d-glucose (FDG) for detecting regional lymph node (LN) metastases of non-small cell lung cancer (NSCLC) were prospectively compared. In addition, the relationship between the PET result and the patient's prognosis was evaluated.

Methods

A total of 31 patients with NSCLC underwent 4DST PET/computed tomography (CT) and FDG PET/CT. The PET/CT images were evaluated qualitatively and quantitatively for focal uptake of each PET tracer, according to the staging system of the American Joint Committee on Cancer. Surgical and histological results provided the reference standards. Patients were followed for up to two years to assess disease-free survival.

Results

On a per-lesion basis, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for LN staging were 82%, 72%, 32%, 96%, and 73%, respectively, for 4DST, and 29%, 86%, 25%, 88%, and 78%, respectively, for FDG. The sensitivity of 4DST was significantly higher than that of FDG (P < 0.001). The disease-free survival rate with positive 4DST uptake in nodal lesions was 0.35, which was considerably lower than the rate of 0.83 with negative findings (P = 0.04). Among the factors tested, nodal staging by 4DST was the most influential prognostic factor (P = 0.05) in predicting the presence of a previously existing spread lesion or of a recurrence over the course of 2 years.

Conclusion

4DST PET/CT is sensitive for detecting mediastinal lymph node metastasis in NSCLC, but its low specificity is a limitation. However, it may be helpful in predicting the prognosis of NSCLC.

Mediastinoscopy: trends and practice patterns in the United States

OBJECTIVES

Historically, mediastinoscopy has been the gold standard for the staging of lung cancer. A practice gap exists as the result of a variation in knowledge concerning current trends and practice patterns of mediastinoscopy usage. In addition, there are regional variations in practice-based learning and patient care. Lessons learned during surgeries performed on patients with lung cancer and other advances such as positron emission tomography and endobronchial ultrasound could be universally applied to improve surgeons' management of patient care. The purpose of this study was to assess contemporary practices in the staging of lung cancer.

METHODS

We queried the Society of Thoracic Surgeons National Database for data regarding mediastinoscopy usage, yield, and variation, both by year and region.

RESULTS

Cases with mediastinoscopy, as a percentage of all cases performed in the database, have significantly decreased from 14.6% in 2006 to 11.4% in 2010 (P < 0.001). The 5-year median rate of mediastinoscopy in lung cancer patients at 163 centers was 15.3% (interquartile range 5.2%-31.7%), indicating significant variation among centers. The overall median center rate also decreased over time from 21.4% (2006) to 10.0% (2010).

CONCLUSIONS

With advances in minimally invasive procedures and imaging, mediastinoscopy usage has declined significantly. Our findings are likely to be relevant to both clinical practice and practice guidelines.

Methods for staging non-small cell lung cancer: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines

BACKGROUND

Correctly staging lung cancer is important because the treatment options and prognosis differ significantly by stage. Several noninvasive imaging studies and invasive tests are available. Understanding the accuracy, advantages, and disadvantages of the available methods for staging non-small cell lung cancer is critical to decision-making.

METHODS

Test accuracies for the available staging studies were updated from the second iteration of the American College of Chest Physicians Lung Cancer Guidelines. Systematic searches of the MEDLINE database were performed up to June 2012 with the inclusion of selected meta-analyses, practice guidelines, and reviews. Study designs and results are summarized in evidence tables.

RESULTS

The sensitivity and specificity of CT scanning for identifying mediastinal lymph node metastasis were approximately 55% and 81%, respectively, confirming that CT scanning has limited ability either to rule in or exclude mediastinal metastasis. For PET scanning, estimates of sensitivity and specificity for identifying mediastinal metastasis were approximately 77% and 86%, respectively. These findings demonstrate that PET scanning is more accurate than CT scanning, but tissue biopsy is still required to confirm PET scan findings. The needle techniques endobronchial ultrasound-needle aspiration, endoscopic ultrasound-needle aspiration, and combined endobronchial ultrasound/endoscopic ultrasound-needle aspiration have sensitivities of approximately 89%, 89%, and 91%, respectively. In direct comparison with surgical staging, needle techniques have emerged as the best first diagnostic tools to obtain tissue. Based on randomized controlled trials, PET or PET-CT scanning is recommended for staging and to detect unsuspected metastatic disease and avoid noncurative resections.

CONCLUSIONS

Since the last iteration of the staging guidelines, PET scanning has assumed a more prominent role both in its use prior to surgery and when evaluating for metastatic disease. Minimally invasive needle techniques to stage the mediastinum have become increasingly accepted and are the tests of first choice to confirm mediastinal disease in accessible lymph node stations. If negative, these needle techniques should be followed by surgical biopsy. All abnormal scans should be confirmed by tissue biopsy (by whatever method is available) to ensure accurate staging. Evidence suggests that more complete staging improves patient outcomes.

High dose involved field radiation therapy as salvage for loco-regional recurrence of non-small cell lung cancer

PURPOSE

To determine the effectiveness of salvage radiation therapy (RT) in patients with loco-regional recurrences (LRR) following initial complete resection of non-small cell lung cancer (NSCLC) and assess prognostic factors affecting survivals.

MATERIALS AND METHODS

Between 1994 and 2007, 64 patients with LRR after surgery of NSCLC were treated with high dose RT alone (78.1%) or concurrent chemo-radiation therapy (CCRT, 21.9%) at Samsung Medical Center. Twenty-nine patients (45.3%) had local recurrence, 26 patients (40.6%) had regional recurrence and 9 patients (14.1%) had recurrence of both components. The median RT dose was 54 Gy (range, 44-66 Gy). The radiation target volume included the recurrent lesions only.

RESULTS

The median follow-up time from the start of RT in survivors was 32.0 months. The rates of in-field failure free survival, intra-thoracic failure free survival and extra-thoracic failure free survival at 2 years were 52.3%, 33.9% and 59.4%, respectively. The median survival after RT was 18.5 months, and 2-year overall survival (OS) rate was 47.9%. On both univariate and multivariate analysis, the interval from surgery till recurrence and CCRT were significant prognostic factors for OS.

CONCLUSION

The current study demonstrates that involved field salvage RT is effective for LRR of NSCLC following surgery.

Diagnostic value of fluorine 18 fluorodeoxyglucose positron emission tomography/computed tomography for the detection of metastases in non-small-cell lung cancer patients

In the recent years, fluorine 18 fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET)/computed tomography (CT) has emerged as a new modality for staging non-small-cell lung cancer (NSCLC) patients. The aim of this meta-analysis was to assess the diagnostic value of (18)F-FDG PET/CT in detecting metastatic lesions in NSCLC patients. Meta-analysis methods were used to pool sensitivity, specificity, positive and negative likehood ratios, diagnostic odd ratios and to construct a summary receiver-operating characteristic curve. Data from included studies were pooled to compare the diagnostic accuracy between PET/CT and PET or CT alone in nodal staging. Totally, 56 studies involving 8,699 patients met the inclusion criteria. The pooled sensitivities and specificities of (18)F-FDG PET/CT were 0.72 [95% confidence interval (CI): 0.65-0.78] and 0.91 (95% CI: 0.86-0.94) in determining mediastinal nodal staging; 0.71 (95% CI: 0.60-0.80) and 0.83 (95% CI: 0.77-0.88) in intrathoracic staging; 0.78 (95% CI: 0.64-0.87) and 0.90 (95% CI: 0.84-0.94) in intrathoracic staging on a per-node basis. For detecting extrathoracic metastases, the pooled sensitivities and specificities of (18)F-FDG PET/CT were 0.77 (95% CI: 0.47-0.93) and 0.95 (95% CI: 0.92-0.97) for all extrathoracic metastases; 0.91 (95% CI: 0.80-0.97) and 0.98 (95% CI: 0.94-0.99) for bone metastases. (18)F-FDG PET/CT is beneficial in detecting lymph node metastases and extrathoracic metastases although PET/CT showed low sensitivity in detecting brain metastases. (18)F-FDG PET/CT confers significantly higher sensitivity and specificity than contrast-enhanced CT (both p < 0.01) and higher sensitivity than (18)F-FDG PET in staging NSCLC (p < 0.05).

(18)FDG-PET/CT for detection of mediastinal nodal metastasis in non-small cell lung cancer: a meta-analysis

BACKGROUND

We performed a meta-analysis to evaluate the role of (18)F-fluorodeoxyglucos -e positron emission tomography/computed tomography ((18)FDG-PET/CT) in detecting mediastinal nodal metastasis in patients with non-small cell lung cancer (NSCLC).

METHODS

Studies about (18)FDG-PET/CT for detecting mediastinal nodal metastasis in patient with NSCLC were systematically searched in the MEDLINE, EMBASE, and EBM Review databases from January 1, 2000 to July 26, 2011. A software called "Meta-Disc" was used to obtain pooled estimates of sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR), respectively. We also calculated summary receiver operating characteristic (SROC) curves, and the Q* index.

RESULTS

20 articles fulfilled all inclusion criteria (3028 eligible patients). The pooled sensitivity, and specificity with 95% confidence interval for PET/CT on a per-patient analysis were 0.719 (0.683-0.753), and 0.898 (0.882-0.912). Corresponding values for PET/CT on a per-nodal-station analysis were 0.610 (0.582-0.636), 0.924 (0.918-0.930). The Q* index estimates under SROC were 0.8464 and 0.8067, respectively.

CONCLUSIONS

(18)FDG-PET/CT had more specificity but less sensitivity for mediastinal nodal metastasis in patients with NSCLC.

Diagnostic performance of integrated positron emission tomography/computed tomography for mediastinal lymph node staging in non-small cell lung cancer: a bivariate systematic review and meta-analysis

INTRODUCTION

Accurate clinical staging of mediastinal lymph nodes (MLNs) of patients with non-small cell lung cancer (NSCLC) is important in determining therapeutic options and prognoses. Integrated positron emission tomography and computed tomography (PET/CT) scanning is becoming widely used for MLN staging in patients with NSCLC. We performed a bivariate meta-analysis to determine the pooled sensitivity (SEN) and specificity (SPE) of this imaging modality.

METHODS

The PubMed/MEDLINE, Embase, and SpringerLink databases were searched for articles related to PET/CT for MLN staging in patients with NSCLC. SEN and SPE were calculated for every study. Hierarchical summary receiver operating characteristic curves were used to summarize overall test performance and assess study quality. Potential between-study heterogeneity was explored by subgroup analyses.

RESULTS

Fourteen of 330 initially identified reports were included in the meta-analysis. When we did not consider the unit of analysis, the pooled weighted SEN and SPE were 0.73 (95% confidence interval [CI]: 0.65-0.79) and 0.92 (95% CI: 0.88-0.94), respectively. In the patient-based data analysis, the pooled weighted SEN was 0.76 (95% CI: 0.65-0.84) and the pooled weighted SPE was 0.88 (95% CI: 0.82-0.92). In the MLN-based data analysis, the pooled SEN was 0.68 (95% CI: 0.56-0.78) and the pooled SPE was 0.95 (95% CI: 0.91-0.97).

CONCLUSIONS

Integrated PET/CT is a relatively accurate noninvasive imaging technique, with excellent specificity for MLN staging in patients with NSCLC. Nevertheless, current evidence suggests that we should not depend on the results of PET/CT completely for MLN staging in patients with NSCLC.

EBUS-TBNA in mediastinal/hilar lymphadenopathies and/or masses: an Italian case series

INTRODUCTION

Transbronchial needle aspiration (TBNA) is an established method to diagnose hilar/mediastinal lymphadenopathies and/or masses. Real-time endobronchial ultrasound (EBUS) is a method that involves TBNA, and has been shown to increase the diagnostic yield in this context.

OBJECTIVES

A descriptive study has been conducted to test real-time EBUS in the diagnosis of hilar-mediastinal lymphadenopathies/masses with a shorter diameter less then 2.5 cm or with a previous negative 'blind' TBNA.

METHODS

Consecutive patients referred for EBUS-TBNA of hilar/mediastinal lymph nodes were included in the study, when a node or mass was detected on a chest computed tomography scan. The primary end point was the number of successful biopsy specimens. Lymph node stations were classified according to the American Thoracic Society scheme.

RESULTS

Ninety-four patients (66 males, 28 females) of mean age 62 years (range: 17-86) underwent EBUS-TBNA: EBUS-TBNA could be performed in all patients. The procedure was diagnostic in 80 patients (89.4%); positive samples were 73 (52 lung cancer, 18 sarcoidosis and 3 tuberculosis), negative samples were 17, inadequate specimens were obtained in four patients (4.25%) and surgically proven false negative results were found in six cases (6.38%). Biopsy specimens were taken from lymph nodes in region 2L (1 case), 2R (5 cases), 4R (20 cases), 4L (7 cases), 7 (47 cases), 10R (9 cases), 10L (2 cases), 11R (6 cases) and 11L (3 cases). Sensitivity was 92.4%, and specificity was 100%. No complications occurred.

CONCLUSIONS

EBUS-TBNA is a safe and reliable method for sampling mediastinal lymph nodes.

[Role of mediastinoscopy and repeat mediastinoscopy today]

For patients with lung cancer preoperative evaluation of the mediastinal lymph nodes is important to estimate local operability and/or to consider the necessity of neoadjuvant treatment. Cervical mediastinoscopy is generally accepted as a safe and highly accurate procedure in the staging of lung cancer. Nodes accessible to CM are the levels of the superior (level 2R and 2L) and inferior (level 4R and 4L) paratracheal and subcarinal (level 7) nodal stations. Additionally extended CM and left parasternal mediastinotomy allow the exploration of the aortopulmonary window (level 5) and anterior mediastinal nodes (level 6). In locally advanced lung cancer repeat mediastinoscopy was used after induction chemotherapy or chemoradiation to reexplore the upper mediastinum in order to select patients with a higher probability to undergo complete resection. Operative mortality of both investigations is less than 0.5%; the preoperative complication rate is very low (less than 4%). Because of the higher sensitivity, specificity, and accuracy, mediastinoscopy and repeat mediastinoscopy are superior to new methods like FDG-PET, FDG-PET/CT, EBUS-FNA, and EUS-FNA.