Mediastinal staging of lung cancer: novel concepts

Integral mediastinal staging in patients with NON-SMALL cell lung cancer and risk factors for occult N2 disease

BACKGROUND

In patients with non-small cell lung cancer (NSCLC), the presence of abnormal hiliar lymph nodes (clinical N1; cN1), central tumor location and/or tumor size (diameter >3 cm) increases the risk of occult mediastinal metastasis (OMM). This study investigates prospectively the diagnostic value of an integral mediastinal staging (IMS) strategy that combines EndoBronchial Ultrasound-TransBronchial Needle Aspiration (EBUS-TBNA) and Video-Assisted Mediastinoscopy (VAM) in patients with NSCLC at risk of OMM.

METHODS

Patients with NSCLC and radiologically normal mediastinum assessed non-invasively by positron emission tomography and computed tomography of the chest (PET-CT), and OMM risk factors (cN1, central tumor and/or >3 cm) underwent EBUS-TBNA followed by VAM if the former was negative. Those with negative IMS underwent resection surgery of the tumor.

RESULTS

EBUS-TBNA identified OMM in 2 out of the 49 patients evaluated (4%) and VAM in 1 of the 47 patients with negative EBUS (2%). Two patients with a negative IMS had OMM at surgery. Overall, the prevalence of OMM was 10%. EBUS-TBNA has a sensitivity of 40%, a negative predictive value (NPV) of 93.6%, and negative likelihood ratio of 0.60 (95%CI:0.30-1.16). The risk of not diagnosing OMM after EBUS was 6% and after IMS was 4.4%.

CONCLUSION

Integral mediastinal staging in patients with NSCLC and clinical risk factors for OMM, does not seem to provide added diagnostic value to that of EBUS-TBNA, except perhaps in patients with cN1 disease who deserve further research.

The Value of a Systematic Protocol Using Endobronchial Ultrasound and Endoscopic Ultrasound in Staging of Lung Cancer for Patients with Imaging iN0–N1 Disease

<b><i>Introduction:</i></b> We hypothesize that systematic, combined, and multidisciplinary study of the mediastinum (endobronchial ultrasound [EBUS] and endoscopic ultrasound [EUS]) in patients with NSCLC with radiologically normal mediastinum improves the results of mediastinal staging obtained with EBUS alone. <b><i>Material and Methods:</i></b> A retrospective study of the prospective database collected on the patients with NSCLC with a radiologically normal mediastinum and an indication for systematic staging with EBUS and EUS. EBUS staging was followed by EUS in patients in which the results from the pathological analysis of EBUS were negative. <b><i>Results:</i></b> Forty-five patients were included in the analysis. The combination of EBUS followed by EUS provided better results than EBUS alone: sensitivity (S) 95% versus 80%, negative predictive value (NPV) 96.15% versus 86.21%, negative likelihood ratio 0.05 versus 0.20, and post-test probability 3.8% versus 13.8%. This represents an increase in S (15%), the validity index (6.6%), and NPV (9.9%) compared to EBUS alone. There were 4 false negatives (FNs) (8.8%) with the EBUS test alone. After adding EUS, 3 more cases were positive (6.6%) and only 1 FN (2.2%). <b><i>Conclusions:</i></b> In patients with NSCLC and a radiographically normal mediastinum, a systematic and combined staging with EBUS and EUS show higher sensitivity in the detection of mediastinal metastasis than with the use of EBUS alone. The high accuracy of the test means that the use of mediastinoscopy is not necessary to confirm the results in these patients. Since the availability of EUS is low, it may be advisable for the interventional pulmonologist to receive training in EUS-b.

Development and Validation of a 18F-FDG PET-Based Radiomic Model for Evaluating Hypermetabolic Mediastinal-Hilar Lymph Nodes in Non-Small-Cell Lung Cancer

Background

Accurate evaluation of lymph node (LN) status is critical for determining the treatment options in patients with non-small cell lung cancer (NSCLC). This study aimed to develop and validate a ¹⁸F-FDG PET-based radiomic model for the identification of metastatic LNs from the hypermetabolic mediastinal–hilar LNs in NSCLC.

Methods

We retrospectively reviewed 259 patients with hypermetabolic LNs who underwent pretreatment ¹⁸F-FDG PET/CT and were pathologically confirmed as NSCLC from two centers. Two hundred twenty-eight LNs were allocated to a training cohort (LN = 159) and an internal validation cohort (LN = 69) from one center (7:3 ratio), and 60 LNs were enrolled to an external validation cohort from the other. Radiomic features were extracted from LNs of PET images. A PET radiomics signature was constructed by multivariable logistic regression after using the least absolute shrinkage and selection operator (LASSO) method with 10-fold cross-validation. The PET radiomics signature (model 1) and independent predictors from CT image features and clinical data (model 2) were incorporated into a combined model (model 3). A nomogram was plotted for the complex model, and the performance of the nomogram was assessed by its discrimination, calibration, and clinical usefulness.

Results

The area under the curve (AUC) values of model 1 were 0.820, 0.785, and 0.808 in the training, internal, and external validation cohorts, respectively, showing good diagnostic efficacy for lymph node metastasis (LNM). Furthermore, model 2 was able to discriminate metastatic LNs in the training (AUC 0.780), internal (AUC 0.794), and external validation cohorts (AUC 0.802), respectively. Model 3 showed optimal diagnostic performance among the three cohorts, with an AUC of 0.874, 0.845, and 0.841, respectively. The nomogram based on the model 3 showed good discrimination and calibration.

Conclusions

Our study revealed that PET radiomics signature, especially when integrated with CT imaging features, showed the ability to identify true and false positives of mediastinal–hilar LNM detected by PET/CT in patients with NSCLC, which would help clinicians to make individual treatment decisions.

Clinical application of ultrasound-guided mediastinal lymph node biopsy through cervical mediastinoscopy

BACKGROUND

Cervical mediastinoscopy is useful for diagnosing lung and mediastinal disease. Ultrasound is a safe real-time diagnostic tool widely employed in many surgical fields. Ultrasound was used in cervical mediastinoscopy in our cohort with satisfactory results. This study investigated the safety, feasibility, and availability of video-assisted mediastinoscopy (VAM) combined with ultrasound for mediastinal lymph node biopsy.

METHODS

A total of 87 cases involving cervical mediastinal lymph node biopsy performed from November 2015 to May 2020, with complete clinical and pathological information, were retrospectively analyzed in the Department of Thoracic Surgery at Beijing Chaoyang Hospital. The cohort was divided into two groups: ultrasound-guided biopsy under video-assisted mediastinoscopy (UVAM) (44 cases) and routine VAM (43 cases). Operation time, biopsy number and nodal stations, postoperative complications, pathological conditions, and surgical difficulty were compared between the two nodal stations.

RESULTS

UVAM was significantly shorter and more lymph node specimens were obtained than with VAM. There was one case of fatal bleeding and two cases of right recurrent laryngeal nerve injury in the VAM group, and no postoperative complications in the UVAM group.

CONCLUSIONS

When used with cervical VAM, ultrasound guidance assists physicians assess the space between lymph nodes, surrounding tissues, and large vessels systematically, making biopsy safer and easier, improving lymph node sampling, and decreasing postoperative complications. Furthermore, surgeons can easily learn and master this method.

KEY POINTS

Significant findings of the study: Ultrasound was used in combination with cervical mediastinoscopy and the results showed that ultrasound guidance makes biopsy in patients safer and easier, improves lymph node sampling, and decreases postoperative complications.

WHAT THIS STUDY ADDS

Surgeons can easily learn and master this method.

Endobronchial Ultrasound Elastography for Differentiating Benign and Malignant Lymph Nodes

BACKGROUND

Endobronchial ultrasound elastography that provides information on tissue stiffness may help distinguish malignant from benign mediastinal and hilar lymph nodes.

OBJECTIVES

In this prospective trial, we assessed the diagnostic value of elastographic images and the interobserver agreement in its evaluation.

METHOD

Elastographic images from 77 lymph nodes in 65 patients were reviewed by 3 pneumologists. The elastographic image was classified based on the predominant colour: predominantly green, intermediary, and predominantly blue. With 2 or 3 interobserver matches, the corresponding elastographic image was correlated with the pathological result obtained from endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and/or other invasive procedures.

RESULTS

All 3 reviewers had agreement in classifying elastographic images in 45% (35/77). Overall, the interobserver agreement among the 3 readers for classifying elastographic pattern was found to be moderate (Fleiss Kappa index = 0.519; 95% CI = [0.427; 0.611]). On cytological/histological evaluation, 55 lymph nodes were malignant and 22 were benign. In classifying "green" as benign and "blue" as malignant, the sensitivity and specificity were 71% (95% CI = [54%; 85%]) and 67% (95%-CI = [35%; 90%]), respectively.

CONCLUSIONS

Elastography will not replace invasive EBUS-TBNA due to a moderate interobserver agreement and insufficient sensitivity and specificity. However, elastography will, maybe, present an additional feature to identify malignant lymph nodes in the context of clinical, radiological, and cytological results.

Minimizing residual occult nodal metastasis in NSCLC: recent advances, current status and controversies

Introduction: Nodal involvement in lung cancer is a significant determinant of prognosis and treatment management. New evidence exists regarding the management of occult lymph node metastasis and residual disease in the fields of imaging, mediastinal staging, and operative management.Areas covered: This review summarizes the latest body of knowledge on the identification and management of occult lymph node metastasis in NSCLC. We focus on tumor-specific characteristics; imaging modalities; invasive mediastinal staging; and operative management including, technique, degree of resection, and lymph node examination.Expert opinion: Newly identified risk-factors associated with nodal metastasis including tumor histology, location, radiologic features, and metabolic activity are not included in professional societal guidelines due to the heterogeneity of their reporting and uncertainty on how to adopt them into practice. Imaging as a sole diagnostic method is limited. We recommend confirmation with invasive mediastinal staging. EBUS-FNA is the best initial method, but adoption has not been uniform. The diagnostic algorithm is less certain for re-staging of mediastinal nodes after neoadjuvant therapy. Mediastinal node sampling during lobectomy remains the gold-standard, but evidence supports the use of minimally invasive techniques. More study is warranted regarding sublobar resection. No consensus exists regarding lymph node examination, but new evidence supports reexamination of current quality metrics.

Discrimination of mediastinal metastatic lymph nodes in NSCLC based on radiomic features in different phases of CT imaging

Background

We aimed to develop radiomic models based on different phases of computed tomography (CT) imaging and to investigate the efficacy of models for diagnosing mediastinal metastatic lymph nodes (LNs) in non-small cell lung cancer (NSCLC).

Methods

Eighty-six NSCLC patients were enrolled in this study, and we selected 231 mediastinal LNs confirmed by pathology results as the subjects which were divided into training (n = 163) and validation cohorts (n = 68). The regions of interest (ROIs) were delineated on CT scans in the plain phase, arterial phase and venous phase, respectively. Radiomic features were extracted from the CT images in each phase. A least absolute shrinkage and selection operator (LASSO) algorithm was used to select features, and multivariate logistic regression analysis was used to build models. We constructed six models (orders 1–6) based on the radiomic features of the single- and dual-phase CT images. The performance of the radiomic model was evaluated by the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV).

Results

A total of 846 features were extracted from each ROI, and 10, 9, 5, 2, 2, and 9 features were chosen to develop models 1–6, respectively. All of the models showed excellent discrimination, with AUCs greater than 0.8. The plain CT radiomic model, model 1, yielded the highest AUC, specificity, accuracy and PPV, which were 0.926 and 0.925; 0.860 and 0.769; 0.871 and 0.882; and 0.906 and 0.870 in the training and validation sets, respectively. When the plain and venous phase CT radiomic features were combined with the arterial phase CT images, the sensitivity increased from 0.879 and 0.919 to 0.949 and 0979 and the NPV increased from 0.821 and 0.789 to 0.878 and 0.900 in the training group, respectively.

Conclusions

All of the CT radiomic models based on different phases all showed high accuracy and precision for the diagnosis of LN metastasis (LNM) in NSCLC patients. When combined with arterial phase CT, the sensitivity and NPV of the model was be further improved.

Present indications of surgical exploration of the mediastinum

Preoperative mediastinal staging is crucial in the management of patients with non-small cell lung cancer (NSCLC), especially to define prognosis and the most proper treatment. To obtain the highest certainty level before lung resection, the current American and European guidelines for preoperative mediastinal nodal staging for NSCLC recommend getting tissue confirmation of regional nodal spread in all cases except in patients with small (≤3 cm) peripheral carcinomas with no evidence of nodal involvement on computed tomography (CT) and positron emission tomography (PET). We have a wide variety of surgical methods for mediastinal staging that are well integrated in the current preoperative algorithms. Their main indication is the validation of negative results obtained by minimally invasive endoscopic techniques. However, recent studies have reported the superiority of mediastinoscopy over endosonography methods in terms of accuracy for those tumours classified as clinical (c) N0-1 by CT and PET or with intermediate risk of N2 disease (cN1 and central tumours). Apart from the exploration of the mediastinum, other surgical procedures [parasternal mediastinotomy, extended cervical mediastinoscopy (ECM) and video-assisted thoracoscopic surgery (VATS)] allow the completion of the staging process with the assessment of the primary tumour and metastasis, exploring the lung, pleural cavity, and pericardium when it is required. Transcervical lymphadenectomies represent the evolution of mediastinoscopy and they are already considered the most reliable method for mediastinal staging, mainly in the subgroup of patients in whom endosonography methods have a low sensitivity: tumours with normal mediastinum by CT and PET. In addition to their indication for staging, these procedures have also demonstrated to be feasible as preresectional lymphadenectomy in VATS lobectomy, improving the radicality of the number of lymph nodes and lymph node stations explored, mostly for left-sided tumours for which a complete mediastinal nodal dissection is not always possible by VATS approach.

Lung cancer staging: a concise update

Diagnosis and clinical staging of lung cancer are fundamental to planning therapy. The techniques for clinical staging, i.e anatomic and metabolic imaging, endoscopies and minimally invasive surgical procedures, should be performed sequentially and with an increasing degree of invasiveness. Intraoperative staging, assessing the magnitude of the primary tumour, the involved structures, and the loco-regional lymphatic spread by means of systematic nodal dissection, is essential in order to achieve a complete resection. In resected tumours, pathological staging, with the systematic study of the resected specimens, is the strongest prognostic indicator and is essential to make further decisions on therapy. In the present decade, the guidelines on lung cancer staging of the American College of Chest Physicians and the European Society of Thoracic Surgeons are based on the best available evidence and are widely followed. Recent advances in the classification of the adenocarcinoma of the lung, with the definition of adenocarcinoma in situ, minimally invasive adenocarcinoma and lepidic predominant adenocarcinoma, and the publication of the eighth edition of the tumour, node and metastasis classification of lung cancer, have to be integrated into the staging process. The present review complements the latest guidelines on lung cancer staging by providing an update of all these issues.

Mediastinal staging by videomediastinoscopy in clinical N1 non-small cell lung cancer: a prospective multicentre study

A quarter of patients with clinical N1 (cN1) non-small cell lung cancer (NSCLC) based on positron emission tomography-computed tomography (PET-CT) imaging have occult mediastinal nodal involvement (N2 disease). In a prospective study, endosonography alone had an unsatisfactory sensitivity (38%) in detecting N2 disease. The current prospective multicentre trial investigated the sensitivity of preoperative mediastinal staging by video-assisted mediastinoscopy (VAM) or VAM-lymphadenectomy (VAMLA).Consecutive patients with operable and resectable (suspected) NSCLC and cN1 after PET-CT imaging underwent VAM(LA). The primary study outcome was sensitivity to detect N2 disease. Secondary endpoints were the prevalence of N2 disease, negative predictive value (NPV) and accuracy of VAM(LA).Out of 105 patients with cN1 on imaging, 26% eventually developed N2 disease. Invasive mediastinal staging with VAM(LA) had a sensitivity of 73% to detect N2 disease. The NPV was 92% and accuracy 93%. Median number of assessed lymph node stations during VAM(LA) was 4 (IQR 3-5), and in 96%, at least three stations were assessed.VAM(LA) has a satisfactory sensitivity of 73% to detect mediastinal nodal disease in cN1 lung cancer, and could be the technique of choice for pre-resection mediastinal lymph node assessment in this patient group with a one in four chance of occult-positive mediastinal nodes after negative PET-CT.

Upfront surgery as first-line therapy in selected patients with stage IIIA non-small cell lung cancer

OBJECTIVE

Surgery plays an important role in the multidisciplinary treatment strategy for patients with stage IIIA non-small cell lung cancer (NSCLC). Besides induction therapy, patients could benefit from surgery followed by adjuvant chemotherapy and radiotherapy. This study analyzed a subset of patients with pIIIA NSCLC who underwent upfront surgery as first-line therapy.

METHODS

Selected patients with pIIIA NSCLC who received upfront surgery were retrospectively analyzed. Clinicopathologic characteristics and survival outcomes including progression-free survival (PFS) and overall survival (OS) were evaluated.

RESULTS

A total of 668 patients were identified. Five hundred sixty-five patients received adjuvant chemotherapy, and 157 patients received adjuvant radiotherapy after surgery. The median PFS and OS were 17.0 and 44.0 months, respectively. The 3-year and 5-year PFS rates were 31.6% and 21.0%, and the 3-year and 5-year OS rates were 54.7% and 43.0%. Patients with adenocarcinoma (AD) had better OS than those with squamous cell carcinoma (5-year OS: P = .026). Patients with low-grade AD (acinar and papillar) had a similar PFS and OS compared with patients with high-grade AD (solid, micropapillary, and mucinous) (5-year PFS: P = .894; 5-year OS: P = .439). Patients with mutated epidermal growth factor receptor had a similar OS to patients with wild-type epidermal growth factor receptor (5-year OS: P = .121). Patients with clinical N0 status (P = .004) and patients with single-station of pathologic N2 (P < .001) had better OS.

CONCLUSIONS

Upfront surgery followed by adjuvant therapy may provide favorable survival outcomes for selected patients with pIIIA NSCLC, especially for patients with AD or patients with clinical N0 and pathologic single-station N2 diseases.

Radiomic Analysis using Density Threshold for FDG-PET/CT-Based N-Staging in Lung Cancer Patients

PURPOSE

Mediastinal nodal (N)-staging done by integrated 2-deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]FDG) positron emission tomography/x-ray computed tomography (PET/CT) in lung cancer patients is not always accurate. In order to reduce the need for invasive staging procedures, additional surrogate parameters for the detection of malignant lymph node infiltration would be helpful. The purpose of this study was to evaluate if radiomic semi-automated density profiling in mediastinal lymph nodes can improve preclinical N-staging, irrespective of the specific lung cancer entity.

PROCEDURES

This retrospective study was approved by the institutional review board. Two hundred forty-eight histologically proven lymph nodes in 122 lung cancer patients were investigated. In malignantly infiltrated lymph nodes, the specific lung cancer entity was histologically classified; benign lymph nodes were histologically classified as benign. Non-contrast enhanced [¹⁸F]FDG-PET/CT was performed before surgery/biopsy. Lymph node analyses were performed on the basis of FDG uptake and volumetric CT histogram analysis for metric lymph node sampling.

RESULTS

Of the 248 lymph nodes, 118 were benign, 130 malignant. Malignant lymph nodes had a significantly higher median CT density (32.4 Hounsfield units (HU) (min 5.4/max 77.5 HU)) compared to benign lymph nodes (9.3 HU (min -49.5/max 60.4 HU, p < 0.05), irrespective of the histological subtype. The discrimination between different malignant tumour subtypes by means of volumetric density analysis failed. Irrespective of the malignant subtype, a possible cutoff value of 20 HU may help differentiate between benign and malignant lymph nodes.

CONCLUSION

Density measurements in unclear mediastinal and hilar lymph nodes with equivocal FDG uptake in PET might serve as a possible surrogate parameter for N-staging in lung cancer patients, irrespective of the specific lung cancer subtype. This could also help to find possible high yield targets in cases where invasive lymph node staging is necessary.

Added value of combined endobronchial and oesophageal endosonography for mediastinal nodal staging in lung cancer: a systematic review and meta-analysis

BACKGROUND

Guidelines recommend endosonography with fine-needle aspiration for mediastinal nodal staging in non-small-cell lung cancer, but most do not specify whether this should be through endobronchial endoscopy (EBUS), oesophageal endoscopy (EUS), or both. We assessed the added value and diagnostic accuracy of the combined use of EBUS and EUS.

METHODS

For this systematic review and random effects meta-analysis, we searched MEDLINE, Embase, BIOSIS Previews, and Web of Science, without language restrictions, for studies published between Jan 1, 2000, and Feb 25, 2016. We included studies that assessed the accuracy of the combined use of EBUS and EUS in detecting mediastinal nodal metastases (N2/N3 disease) in patients with lung cancer. For each included study, we extracted data on the age and sex of participants, inclusion criteria regarding tumour stage on imaging, details of the endoscopic testing protocol, duration of each endoscopic procedure, number of lymph nodes sampled, serious adverse events occurring during the endoscopic procedures, the reference standard, and 2 × 2 tables for EBUS, EUS, and the combined approach. We evaluated the added value (absolute increase in sensitivity and in detection rate) of the combined use of EBUS and EUS in detecting mediastinal nodal metastases over either test alone, and the diagnostic accuracy (sensitivity and negative predictive value) of the combined approach. This study is registered with PROSPERO, number CRD42015019249.

FINDINGS

We identified 2567 unique manuscripts by database search, of which 13 studies (including 2395 patients) were included in the analysis. Median prevalence of N2/N3 disease was 34% (range 23-71). On average, addition of EUS to EBUS increased sensitivity by 0·12 (95% CI 0·08-0·18) and addition of EBUS to EUS increased sensitivity by 0·22 (0·16-0·29). Mean sensitivity of the combined approach was 0·86 (0·81-0·90), and the mean negative predictive value was 0·92 (0·89-0·93). The mean negative predictive value was significantly higher in studies with a prevalence of 34% or less (0·93 [95% CI 0·91-0·95]) compared with studies with a prevalence of more than 34% (0·89 [0·85-0·91]; p=0·013). We found no significant differences in mean sensitivity and negative predictive value between studies that did EBUS first or EUS first, or between studies that used an EBUS-scope or a regular echoendoscope to do EUS.

INTERPRETATION

The combined use of EBUS and EUS significantly improves sensitivity in detecting mediastinal nodal metastases, reducing the need for surgical staging procedures.

FUNDING

No external funding.

Integrin Imaging with 99mTc-3PRGD2 SPECT/CT Shows High Specificity in the Diagnosis of Lymph Node Metastasis from Non-Small Cell Lung Cancer

Purpose To evaluate an integrin imaging approach based on single photon emission computed tomography (SPECT)/computed tomography (CT) by using technetium 99m (^99mTc)-dimeric cyclic arginine-glycine-aspartic acid (RGD) peptides with three polyethylene glycol spacers (3PRGD2) as the tracer to target the integrin α_vβ₃ expression in lung cancer and lymph node metastasis. Materials and Methods With ethics committee approval and written informed consent, 65 patients (41 male, 24 female; mean age, 60 years ± 11 [standard deviation]) with suspicious lung lesions were recruited with informed consent. The patients underwent both ^99mTc-3PRGD2 SPECT/CT and fluorine 18 (¹⁸F) fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT within 1 week. Finally, 65 lung lesions in 53 patients were pathologically diagnosed as non-small cell lung cancer (NSCLC) and 14 lung lesions in 12 patients were benign. Per-region analysis of lymph nodes included 248 regions with metastasis and 56 negative regions. Twenty specimens from the removed lung lesions or lymph nodes were stained with integrin α_vβ₃, CD34, and Ki-67 to correlate with the image findings. Receiver operating characteristic curve, z statistics, McNemar test, and χ² analysis were used to compare the diagnostic performance of the two imaging methods. Results ^99mTc-3PRGD2 SPECT/CT was found to be more specific than ¹⁸F-FDG PET/CT in the per-region diagnosis of lymph node metastasis (specificity, 94.6% vs 75.0%; P = .008) when the sensitivity of the two methods was comparable (88.3% vs 90.7%; P = .557). There was no significant difference between the two methods in the per-lesion diagnosis of lung tumor (z = 0.82, P = .410). The accumulation level of ^99mTc-3PRGD2 was found in positive correlation with the integrin α_vβ₃ expression (r = 0.84, P = .001) and microvessel density (r = 0.63, P = .011) in the tumors. Conclusion ^99mTc-3PRGD2 SPECT/CT shows high specificity in the diagnosis of lymph node metastasis from NSCLC, which may benefit surgical decision making for the patients. ^© RSNA, 2016.

Impact of Endobronchial Ultrasound Guided Transbronchial Needle Aspiration on Diagnostic Yield of Bronchoscopy in Patients with Mediastinal Lymph Node Enlargement

Endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) had an enormous impact on the current advancement in diagnostic bronchoscopy. The aims of the present study were: (1) to evaluate the added value of EBUS-TBNA to routine diagnostic bronchoscopy performed in patients with mediastinal lymph node enlargement and (2) to identify factors that affect the diagnostic yield of EBUS-TBNA. We retrospectively analyzed 712 EBUS-TBNA procedures out of the 4081 bronchoscopies performed in the years 2009-2014. The number of EBUS-TBNA procedures increased from 61 (8.8 % of all bronchoscopies) in 2009 to 160 (21.4 %) in 2014. In 625 (87.8 %) patients adequate cytological material was obtained. Based on cytological examination of EBUS-TBNA aspirates, specific diagnosis was made in 367 (51.5 %) patients. The forceps biopsy of endobronchial lesions provided specific diagnosis in only 204 (28.6 %) patients. The percentage of patients with EBUS-TBNA based diagnosis increased steadily from 34.4 % in 2009 to 65.0 % in 2014 (p < 0.0001). The median lymph node diameter in patients with positive EBUS-TBNA findings was 20 (IQR 15-30) mm and was significantly larger than that in patients with negative EBUS-TBNA results (15 (IQR 10-20) mm, p = 0.0001). The highest diagnostic yield (78.5 %) was found in patients with lymph node dimension between 31 mm and 40 mm. We conclude that EBUS-TBNA is a valuable diagnostic method in an unselected group of patients with mediastinal lymph node enlargement. The percentage of positive EBUS-TBNA diagnoses is related to lymph node dimensions. The overall efficacy of EBUS-TBNA improves with increasing years of experience.

Ultrasound techniques in the evaluation of the mediastinum, part 2: mediastinal lymph node anatomy and diagnostic reach of ultrasound techniques, clinical work up of neoplastic and inflammatory mediastinal lymphadenopathy using ultrasound techniques and how to learn mediastinal endosonography

Ultrasound imaging has gained importance in pulmonary medicine over the last decades including conventional transcutaneous ultrasound (TUS), endoscopic ultrasound (EUS), and endobronchial ultrasound (EBUS). Mediastinal lymph node (MLN) staging affects the management of patients with both operable and inoperable lung cancer (e.g., surgery vs. combined chemoradiation therapy). Tissue sampling is often indicated for accurate nodal staging. Recent international lung cancer staging guidelines clearly state that endosonography should be the initial tissue sampling test over surgical staging. Mediastinal nodes can be sampled from the airways [endobronchial ultrasound combined with transbronchial needle aspiration (EBUS-TBNA)] or the esophagus [endoscopic ultrasound fine needle aspiration (EUS-FNA)]. EBUS and EUS have a complementary diagnostic yield and in combination virtually all MLNs can be biopsied. Additionally endosonography has an excellent yield in assessing granulomas in patients suspected of sarcoidosis. The aim of this review in two integrative parts is to discuss the current role and future perspectives of all ultrasound techniques available for the evaluation of mediastinal lymphadenopathy and mediastinal staging of lung cancer. A specific emphasis will be on learning mediastinal endosonography. Part 1 deals with an introduction into ultrasound techniques, MLN anatomy and diagnostic reach of ultrasound techniques and part 2 with the clinical work up of neoplastic and inflammatory mediastinal lymphadenopathy using ultrasound techniques and how to learn mediastinal endosonography.

Ten Years of Linear Endobronchial Ultrasound: Evidence of Efficacy, Safety and Cost-effectiveness

Real-time endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is one of the major landmarks in the history of bronchoscopy. In the 10 years since it was introduced, a vast body of literature on the procedure and its results support the use of this technique in the study of various mediastinal and pulmonary lesions. This article is a comprehensive, systematic review of all the available scientific evidence on the more general indications for this technique. Results of specific studies on efficacy, safety and cost-effectiveness available to date are examined. The analysis shows that EBUS-TBNA is a safe, cost-effective technique with a high grade of evidence that is a valuable tool in the diagnosis and mediastinal staging of patients with suspected or confirmed lung cancer. However, more studies are needed to guide decision-making in the case of a negative result. Evidence on the role of EBUS-TBNA in the diagnosis of sarcoidosis and extrathoracic malignancies is also high, but much lower when used in the study of tuberculosis, lymphoma and for the re-staging of lung cancer after neoadjuvant chemotherapy. Nevertheless, due to its good safety record and lack of invasiveness compared to surgical techniques, the grade of evidence for recommending EBUS-TBNA as the initial diagnostic test in patients with these diseases is very high in most cases.

Ultrasound techniques in the evaluation of the mediastinum, part I: endoscopic ultrasound (EUS), endobronchial ultrasound (EBUS) and transcutaneous mediastinal ultrasound (TMUS), introduction into ultrasound techniques

Ultrasound imaging has gained importance in pulmonary medicine over the last decades including conventional transcutaneous ultrasound (TUS), endoscopic ultrasound (EUS), and endobronchial ultrasound (EBUS). Mediastinal lymph node staging affects the management of patients with both operable and inoperable lung cancer (e.g., surgery vs. combined chemoradiation therapy). Tissue sampling is often indicated for accurate nodal staging. Recent international lung cancer staging guidelines clearly state that endosonography (EUS and EBUS) should be the initial tissue sampling test over surgical staging. Mediastinal nodes can be sampled from the airways [EBUS combined with transbronchial needle aspiration (EBUS-TBNA)] or the esophagus [EUS fine needle aspiration (EUS-FNA)]. EBUS and EUS have a complementary diagnostic yield and in combination virtually all mediastinal lymph nodes can be biopsied. Additionally endosonography has an excellent yield in assessing granulomas in patients suspected of sarcoidosis. The aim of this review, in two integrative parts, is to discuss the current role and future perspectives of all ultrasound techniques available for the evaluation of mediastinal lymphadenopathy and mediastinal staging of lung cancer. A specific emphasis will be on learning mediastinal endosonography. Part I is dealing with an introduction into ultrasound techniques, mediastinal lymph node anatomy and diagnostic reach of ultrasound techniques and part II with the clinical work up of neoplastic and inflammatory mediastinal lymphadenopathy using ultrasound techniques and how to learn mediastinal endosonography.

Stereotactic ablative radiotherapy versus lobectomy for operable stage I non-small-cell lung cancer: a pooled analysis of two randomised trials

BACKGROUND

The standard of care for operable, stage I, non-small-cell lung cancer (NSCLC) is lobectomy with mediastinal lymph node dissection or sampling. Stereotactic ablative radiotherapy (SABR) for inoperable stage I NSCLC has shown promising results, but two independent, randomised, phase 3 trials of SABR in patients with operable stage I NSCLC (STARS and ROSEL) closed early due to slow accrual. We aimed to assess overall survival for SABR versus surgery by pooling data from these trials.

METHODS

Eligible patients in the STARS and ROSEL studies were those with clinical T1-2a (<4 cm), N0M0, operable NSCLC. Patients were randomly assigned in a 1:1 ratio to SABR or lobectomy with mediastinal lymph node dissection or sampling. We did a pooled analysis in the intention-to-treat population using overall survival as the primary endpoint. Both trials are registered with ClinicalTrials.gov (STARS: NCT00840749; ROSEL: NCT00687986).

FINDINGS

58 patients were enrolled and randomly assigned (31 to SABR and 27 to surgery). Median follow-up was 40·2 months (IQR 23·0-47·3) for the SABR group and 35·4 months (18·9-40·7) for the surgery group. Six patients in the surgery group died compared with one patient in the SABR group. Estimated overall survival at 3 years was 95% (95% CI 85-100) in the SABR group compared with 79% (64-97) in the surgery group (hazard ratio [HR] 0·14 [95% CI 0·017-1·190], log-rank p=0·037). Recurrence-free survival at 3 years was 86% (95% CI 74-100) in the SABR group and 80% (65-97) in the surgery group (HR 0·69 [95% CI 0·21-2·29], log-rank p=0·54). In the surgery group, one patient had regional nodal recurrence and two had distant metastases; in the SABR group, one patient had local recurrence, four had regional nodal recurrence, and one had distant metastases. Three (10%) patients in the SABR group had grade 3 treatment-related adverse events (three [10%] chest wall pain, two [6%] dyspnoea or cough, and one [3%] fatigue and rib fracture). No patients given SABR had grade 4 events or treatment-related death. In the surgery group, one (4%) patient died of surgical complications and 12 (44%) patients had grade 3-4 treatment-related adverse events. Grade 3 events occurring in more than one patient in the surgery group were dyspnoea (four [15%] patients), chest pain (four [15%] patients), and lung infections (two [7%]).

INTERPRETATION

SABR could be an option for treating operable stage I NSCLC. Because of the small patient sample size and short follow-up, additional randomised studies comparing SABR with surgery in operable patients are warranted.

FUNDING

Accuray Inc, Netherlands Organisation for Health Research and Development, NCI Cancer Center Support, NCI Clinical and Translational Science Award.

Endosonography for mediastinal nodal staging of clinical N1 non-small cell lung cancer: a prospective multicenter study

BACKGROUND

Patients with clinical N1 (cN1) lung cancer based on imaging are at risk for malignant mediastinal nodal involvement (N2 disease). Endosonography with a needle technique is suggested over surgical staging as a best first test for preoperative invasive mediastinal staging. The addition of a confirmatory mediastinoscopy seems questionable in patients with a normal mediastinum on imaging. This prospective multicenter trial investigated the sensitivity of preoperative linear endosonography and mediastinoscopy for mediastinal nodal staging of cN1 lung cancer.

METHODS

Consecutive patients with operable and resectable cN1 non-small cell lung cancer underwent a lobe-specific mediastinal nodal staging by endosonography. The primary study outcome was sensitivity to detect N2 disease. The secondary end points were the prevalence of N2 disease, the negative predictive value (NPV) of both endosonography and endosonography with confirmatory mediastinoscopy, and the number of patients needed to detect one additional N2 disease with mediastinoscopy.

RESULTS

Of the 100 patients with cN1 on imaging, 24 patients were diagnosed with N2 disease. Invasive mediastinal nodal staging with endosonography alone has a sensitivity of 38%, which can be increased to 73% by adding a mediastinoscopy. NPV was 81% and 91%, respectively. Ten mediastinoscopies are needed to detect one additional N2 disease missed by endosonography.

CONCLUSIONS

Endosonography alone has an unsatisfactory sensitivity to detect mediastinal nodal metastasis in cN1 lung cancer, and the addition of a confirmatory mediastinoscopy is of added value.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01456429; URL: www.clinicaltrials.gov.

Endoscopic ultrasound in the diagnosis and staging of lung cancer

We reviewed the role of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and esophageal ultrasound guided fine needle aspiration (EUS-FNA) in the pretherapeutic assessment of patients with proven or suspected lung cancer. EUS-FNA and EBUS-TBNA have been shown to have a good diagnostic accuracy in the diagnosis and staging of lung cancer. In the future, these techniques in combination with positron emission tomography/computed tomographic may replace surgical staging in patients with suspected and proven lung cancer, but until then surgical staging remains the gold standard for adequate preoperative evaluation.

Multimodality treatment with surgery for locally advanced non-small-cell lung cancer with n2 disease: a review article

Stage III non-small-cell lung cancer (NSCLC) is composed of a heterogeneous population of lesions (ie, T4N0-3, T3N1-3, and T1a-2aN2-3), which makes it difficult to establish a definitive treatment strategy. Although several retrospective and prospective studies have been conducted to investigate the significance of multimodality treatments with surgery for patients with resectable stage III NSCLC, the role of surgery still remains controversial. In this article, we review the results of retrospective and prospective studies that have investigated the significance of multimodality treatment with surgery for patients with stage III NSCLC, particularly those with mediastinal lymph node metastasis, and the implications for the treatment of this controversial subset of patients.

Minimally invasive endoscopic staging for mediastinal lymphadenopathy in lung cancer: a systematic review protocol

INTRODUCTION

Minimally invasive endoscopic biopsy techniques have been widely available as potential alternatives for mediastinal lesions staging in patients with known or suspected lung cancer. Previous efforts have been made to evaluate the diagnostic performance of specific endoscopic modality alone at the level of the mediastinum for staging lung cancer, however, few studies focus on the accuracy of comparisons between different endoscopic modalities, especially at the level of any individual lymph node station. The objective of our study is to determine the diagnostic yields of different endoscopic modalities for staging mediastinal lymphadenopathy in lung cancer, especially concerning the individual lymph node station.

METHODS/DESIGN

A systematic electronic search of MEDLINE, EMBASE, SinoMed and ISI Web of Science were performed to identify studies evaluating endoscopic modalities accuracy with restriction of English and Chinese languages from inception to an update until May 2014. Data were extracted with the patient as the unit of analysis with regards to the abilities of different endoscopic modalities at the level of mediastinum and particular lymph node station. The methodological quality was assessed independently according to the Quality Assessment of Diagnostic Accuracy Study (QADAS) criteria. An exact binomial rendition of bivariate mixed-effects regression model was used to estimate the pooled sensitivity and specificity. Also, pre-post probability analysis, publication bias analysis and sensitivity analysis were performed for a synthesis of knowledge of this context.

DISSEMINATION

The findings will advance our better available knowledge of optimal clinical decision-making when dealing with staging of mediastinal metastasis in lung cancer.

TRIAL REGISTRATION NUMBER

PROSPERO-NIHR Prospective Register of Systematic Reviews (CRD42014009792).

Endobronchial ultrasound-guided transbronchial needle aspiration for non-small cell lung cancer staging

Real-time endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is an established technique for invasive mediastinal staging of non-small cell lung cancer (NSCLC). Needle-based techniques are now recommended as a first-line diagnostic modality for mediastinal staging. Accurate performance of systematic staging with EBUS-TBNA requires a detailed knowledge of mediastinal anatomy. This examination begins at the N3 lymph nodes, progressing through the N2 and N1 lymph node stations, unless a higher station lymph node is positive for malignant cells by rapid on-site cytologic examination. Objective methods of identifying EBUS-TBNA targets include sampling any lymph node station with a visible lymph node or with a lymph node greater than 5 mm in short axis. Three passes per station or the use of rapid on-site cytologic examination with identification of diagnostic material (tumor or lymphocytes) up to five passes are well-established techniques. Obtaining sufficient tissue for molecular profiling may require performing more than three passes. The operating characteristics of EBUS-TBNA are similar to mediastinoscopy. However, mediastinoscopy should be considered in the setting of a negative EBUS-TBNA and a high posterior probability of N2 or N3 involvement.

Combined endobronchial and transesophageal approach of an ultrasound bronchoscope for mediastinal staging of lung cancer

Background

We evaluated the utility of a combined approach using endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and transesophageal bronchoscopic ultrasound-guided fine-needle aspiration (EUS-FNA-B/E) for mediastinal staging of lung cancer.

Methods

An EBUS-TBNA database was analyzed retrospectively. EUS-FNA-B/E was performed after EBUS-TBNA when mediastinal lymph nodes were not accessible using EBUS-TBNA or when tissue sampling using EBUS-TBNA alone was inadequate.

Results

During the study period, 44 patients were enrolled. EBUS-TBNA and EUS-FNA-B/E were performed on 79 and 52 lymph nodes, respectively. The sensitivity, specificity, and accuracy of mediastinal N-staging using EBUS-TBNA alone were 79%, 100%, and 84%, respectively. The sensitivity, specificity, and accuracy of mediastinal N-staging using a combination of EBUS-TBNA and EUS-FNA-B/E were 100%, 100%, and 100%, respectively. Significant differences in sensitivity (P = 0.008) and accuracy (P = 0.004) of mediastinal N-staging were evident when EBUS-TBNA alone and the combined procedure were compared. The nodal stage shifted higher after use of the EUS-FNA-B/E procedure in six cases (13%). No serious complication associated with the procedures was noted.

Conclusions

Use of a combination of EBUS-TBNA and EUS-FNA-B/E can afford better sensitivity and accuracy of mediastinal N-staging compared with use of EBUS-TBNA alone. Such combined procedures should be considered for examination of lesions that are inaccessible or difficult to access by EBUS-TBNA.

Advances in the diagnosis and treatment of non-small cell lung cancer

The diagnostic and therapeutic landscape of non-small cell lung cancer (NSCLC) has changed dramatically in the past 50 years since the Surgeon General's report on smoking and lung cancer. Early detection is now a reality for lung cancer. The use of low-dose computed tomography scans for early detection decreases mortality and is beginning to be used in routine clinical practice. Technological advances such as positron emission tomography and endobronchial ultrasound have improved the accuracy of NSCLC staging. The cure rate for early-stage NSCLC has improved as a result of multimodality treatment approaches. The role of systemic therapy has also expanded to earlier stages of the disease. In recent years, the initial steps toward personalized medicine by utilization of targeted treatments based on tumor genotype have been undertaken. Emerging technological advances and greater insights into tumor biology are poised to greatly reduce the burden of lung cancer in the years to come.

Role of endobronchial and endoscopic ultrasound in pulmonary medicine

In the last decade, endobronchial ultrasound (EBUS) has evolved into an important tool for diagnostic bronchoscopy in daily practice. EBUS has established as a standard for the diagnosis of hilar or mediastinal lymphadenopathy, as a guidance technique for peripheral pulmonary lesions and for the evaluation of tumor involvement of the tracheobronchial wall or mediastinum. In the meantime, EBUS has also taken a significant role in mediastinal staging in lung cancer patients. However, EBUS plays not only a role in the diagnosis of malignancies, it is also important for the diagnosis of benign disorders.

High resolution MRI for non-invasive mouse lymph node mapping

Mouse models are fundamental to the study and design of new techniques for the cancer diagnosis and treatment. The lymphatic system plays an active role in oncogenesis and metastatic disease progression. However, the in vivo identification of LNs in mice is challenging with conventional imaging modalities since the LN diameter in normal mice is 1-2 mm. Standard dissection techniques are challenging and can only provide endpoint data. Here, we describe high resolution MRI (HR-MRI) approaches for the non-invasive detection of mouse LNs in vivo. We compare in vivo non-invasive HR-MRI methods (without exogenous contrast injections) to the ex vivo dye injection methods for the identification of commonly studied LNs in both normal mice and a mouse model of pancreatic ductal adenocarcinoma (PDAC). We demonstrated the potential to use HR-MRI techniques as a non-invasive imaging assay for visualizing mouse LNs in vivo.

Mediastinal staging in daily practice: endosonography, followed by cervical mediastinoscopy. Do we really need both?

OBJECTIVES

In patients with lung cancer, endosonography has emerged as a minimally invasive method to obtain cytological proof of mediastinal lymph nodes, suspicious for metastases on imaging. In case of a negative result, it is currently recommended that a cervical mediastinoscopy be performed additionally. However, in daily practice, a second procedure is often regarded superfluous. The goal of our study was to assess the additional value of a cervical mediastinoscopy, after a negative result of endosonography, in routine clinical practice.

METHODS

In a retrospective cohort study, the records of 147 consecutive patients with an indication for mediastinal lymph node staging and a negative result of endosonography were analysed. As a subsequent procedure, 124 patients underwent a cervical mediastinoscopy and 23 patients were scheduled for an intended curative resection directly. The negative predictive value (NPV) for both diagnostic procedures was determined, as well as the number of patients who needed to undergo a mediastinoscopy to find one false-negative result of endosonography (number needed to treat (NNT)). Clinical data of patients with a false-negative endosonography were analysed.

RESULTS

When using cervical mediastinoscopy as the gold standard, the NPV for endosonography was 88.7%, resulting in a NNT of 8.8 patients. For patients with fluoro-2-deoxyglucose positron emission tomography positive mediastinal lymph nodes, the NNT was 6.1. Overall, a futile thoracotomy could be prevented in 50% of patients by an additional mediastinoscopy. A representative lymph node aspirate, containing adequate numbers of lymphocytes, did not exclude metastases.

CONCLUSIONS

In patients with a high probability of mediastinal metastases, based on imaging, and negative endosonography, cervical mediastinoscopy should not be omitted, not even when the aspirate seems representative.