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

Combined Endosonographic Mediastinal Lymph Node Staging in Positron Emission Tomography and Computed Tomography Node-Negative Non-Small-Cell Lung Cancer in High-Risk Patients

Positron emission tomography (PET) with computed tomography (CT) is routinely utilized to investigate lymph node (LN) metastases in non-small-cell lung cancer. However, it is less sensitive in normal-sized LNs. This study was performed in order to define the prevalence of mediastinal LN metastases discovered on combined endosonography by endobronchial ultrasound (EBUS) and endoscopic ultrasound (EUS) fine needle aspiration in patients with a radiologically normal mediastinum. This study consists of a retrospective, single-institution, tertiary care referral center review of a prospectively maintained database. Patients were identified from a cohort between January 2009 and December 2014. One hundred and sixty-one patients with biopsy-proven, non-small-cell lung cancer were identified in whom both the preendosonography CT and PET-CT were negative for mediastinal LN metastases. Combined endosonography (EBUS + EUS-FNA) was performed in all patients. Z test was used for statistical analysis. A P value of <0.05 was considered statistically significant. A total of 161 consecutive patients were included. Patients were staged if they had central tumor, tumor size >3 cm, N1 lymph node involvement on PET-CT/CT, or if there was low SUV (<2.5) in the primary tumor. A total of 416 lymph nodes were biopsied in the 161 patients using combined endosonography; 147 with EBUS and 269 with EUS. Mean and median number of lymph nodes biopsied per patient using combined EBUS/EUS was 2.5 and 3, respectively (mean and median EBUS: 0.91 and 2.5; mean and median EUS 1.6 and 3). Endosonographic staging upstaged 13% of patients with radiologically normal lymph nodes in the mediastinum, hilum, lobar, and sublobar regions (confidence interval 8.22-19.20). Twenty-one out of 161 patients (13%) with radiologically normal mediastinum were positive on combined EBUS/EUS staging. Out of 21 patients upstaged on endosonography, 15 (71%) had tumor size >3 cm. Six (28%) had occult N1 disease. Thirteen (61%) had occult N2 disease and 2 (9%) had adrenal involvement. None of the upstaged patients had N1 LN involvement on PET-CT or CT scan. Combined endosonographic lymph node staging should be considered in the pretreatment staging of high-risk patients with non-small-cell lung cancer in the presence of radiologically normal mediastinal lymph nodes due to the significant rate of radiologically occult lymph node metastases.

The Accuracy of Clinical Staging of Stage I-IIIa Non-Small Cell Lung Cancer: An Analysis Based on Individual Participant Data

BACKGROUND

Clinical staging of non-small cell lung cancer (NSCLC) helps determine the prognosis and treatment of patients; few data exist on the accuracy of clinical staging and the impact on treatment and survival of patients. We assessed whether participant or trial characteristics were associated with clinical staging accuracy as well as impact on survival.

METHODS

We used individual participant data from randomized controlled trials (RCTs), supplied for a meta-analysis of preoperative chemotherapy (± radiotherapy) vs surgery alone (± radiotherapy) in NSCLC. We assessed agreement between clinical TNM (cTNM) stage at randomization and pathologic TNM (pTNM) stage, for participants in the control group.

RESULTS

Results are based on 698 patients who received surgery alone (± radiotherapy) with data for cTNM and pTNM stage. Forty-six percent of cases were cTNM stage I, 23% were cTNM stage II, and 31% were cTNM stage IIIa. cTNM stage disagreed with pTNM stage in 48% of cases, with 34% clinically understaged and 14% clinically overstaged. Agreement was not associated with age (P = .12), sex (P = .62), histology (P = .82), staging method (P = .32), or year of randomization (P = .98). Poorer survival in understaged patients was explained by the underlying pTNM stage. Clinical staging failed to detect T4 disease in 10% of cases and misclassified nodal disease in 38%.

CONCLUSIONS

This study demonstrates suboptimal agreement between clinical and pathologic staging. Discrepancies between clinical and pathologic T and N staging could have led to different treatment decisions in 10% and 38% of cases, respectively. There is therefore a need for further research into improving staging accuracy for patients with stage I-IIIa NSCLC.

Systematic and combined endosonographic staging of lung cancer (SCORE study)

Guidelines recommend endosonography for mediastinal nodal staging in patients with resectable nonsmall cell lung cancer (NSCLC). We hypothesise that a systematic endobronchial ultrasound (EBUS) evaluation combined with an oesophageal investigation using the same EBUS bronchoscope (EUS-B) improves mediastinal nodal staging versus the current practice of targeted positron emission tomography (PET)-computed tomography (CT)-guided EBUS staging alone.A prospective, multicentre, international study (NCT02014324) was conducted in consecutive patients with (suspected) resectable NSCLC. After PET-CT, patients underwent systematic EBUS and EUS-B. Node(s) suspicious on CT, PET, EBUS and/or EUS-B imaging and station 4R, 4L and 7 (short axis ≥8 mm) were sampled. For patients without N2/N3 disease determined on endosonography, surgical-pathological staging was the reference standard.229 patients were included in this study. The prevalence of N2/N3 disease was 103 out of 229 patients (45%). A PET-CT-guided targeted approach by EBUS identified 75 patients with N2/N3 disease (sensitivity 73%, 95% CI 63-81%; negative predictive value (NPV) 81%, 95% CI 74-87%). Four additional patients with N2/N3 disease were found by systematic EBUS (sensitivity 77%, 95% CI 67-84%; NPV 84%, 95% CI 76-89%) and five more by EUS-B (84 patients total; sensitivity 82%, 95% CI 72-88%; NPV 87%, 95% CI 80-91%). Additional clinical relevant staging information was obtained in 23 out of 229 patients (10%).Systematic EBUS followed by EUS-B increased sensitivity for the detection of N2/N3 disease by 9% compared to PET-CT-targeted EBUS alone.

Role of EBUS TBNA in Staging of Lung Cancer: A Clinician's Perspective

The treatment of non-small cell lung cancer (NSCLC) includes surgical resection with curative intent in early-stage disease and chemoradiation in the advanced stage disease. Therefore, an accurate preoperative mediastinal lymph node staging is required not only to offer the appropriate treatment but also to avoid unnecessary invasive procedures including thoracotomy. The mediastinal lymph nodes can be sampled using several techniques including mediastinoscopy, surgery (open or video-assisted thoracoscopic surgery), endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA), or endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA). Currently, EBUS-TBNA/EUS-FNA is the preferred modality for sampling mediastinal lymph nodes because of its minimally invasive nature and high diagnostic yield. In this review, we discuss the utility of endosonographic procedures in mediastinal lymph node staging of NSCLC.

Combined Endosonography Reduces Time to Diagnose Pulmonary Coccidioidomycosis

Coccidioidomycosis causes significant morbidity in endemic areas. In the absence of sensitive diagnostic serologic testing, clinicians have increasingly relied on lung and lymph node biopsies for diagnosis. Recently, endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) has been shown to be an excellent sampling method for the diagnosis and staging of lung cancers, especially when combined with endoscopic ultrasound guided fine needle aspiration (EUS-FNA). We present 13 consecutive cases where EBUS-TBNA and/or EUS-FNA of pulmonary lymph nodes were performed as part of the workup for pulmonary coccidioidomycosis. EBUS-TBNA+EUS-FNA led to diagnosis in all nine cases in which they were performed concurrently, and in the remaining 4 in which either was performed individually. BAL was performed in all cases with positive results in 5 (38%). The mean time to diagnose by EBUS/EUS (1.6 d) was significantly shorter than by bronchoalveolar lavage (6.3 d) (P=0.003). The findings indicate that combined EBUS-TBNA+EUS-FNA for lymph node biopsy facilitates early and accurate diagnosis of pulmonary coccidioidomycosis.

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.

Transesophageal approach to lung, adrenal biopsy and fiducial placement using endoscopic ultrasonography (EUS): An interventional pulmonology experience. Initial experience of the UCSF-FRETOC (fresno tracheobronchial & oesophageal center) study group

BACKGROUND

Routine lung cancer surveillance has resulted in early detection of pulmonary nodules and masses. Combined endobronchial ultrasound (EBUS) and trans-esophageal endoscopic ultrasound (EUS) are approved methods for sampling lymph nodes or masses. Furthermore, EUS allows for adrenal sampling as part of staging, and can assist with fiducial placement for stereotactic body radiation therapy (SBRT).

OBJECTIVES

Promote use of EUS by interventional pulmonologists in the United States when diagnosing and staging lung cancer or when placing fiducials.

METHODS

All patients undergoing EUS and/or EBUS were serially entered into a prospectively maintained database. Only patients undergoing EUS guided lung and/or adrenal biopsy and/or fiducial placement were selected for analysis. All patients underwent a post-procedure chest radiograph and were followed outpatient.

RESULTS

20 of 39 patients underwent sampling of a suspicious lung mass. An adequate sample was obtained in 19 of 20 patients. In all 19 patients a definitive diagnosis was achieved (95%). In all 13 patients who underwent adrenal sampling, presence or absence of metastasis was conclusively established. 6 patients successfully underwent fiducial placement. In all 39 patients, no major procedure related complications were noted for a period of 30 days. One patient had a small pneumothorax that resolved spontaneously.

CONCLUSIONS

EUS can be safely performed by a trained interventional pulmonologist for the diagnosis of lung, adrenal masses and placement of fiducials. We think that interventional pulmonologists in the United States involved in lung cancer staging should receive training in EUS techniques.

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.

EBUS: Faster, cheaper and most effective in lung cancer staging

The use of endobronchial ultrasound trans-bronchial needle aspiration (EBUS-TBNA) as the initial diagnostic and staging procedure in patients with suspected, non-metastatic lung cancer has gained substantial support, and is now recommended by numerous guidelines. Whereas considerable attention has been pointed to the reductions in costs achieved by EBUS-TBNA, that has not been the case for some of its more significant benefits, namely the reduction of the diagnostic work-up time and its ability to accurately assess and restage lymph nodes, which were previously stated incorrectly by CT or PET scan. Both these benefits translate into improved outcomes for patients, as delays are reduced, futile surgeries are prevented and curable operations can be performed on patients previously excluded by CT or PET scan. Indeed, the use of EBUS as the initial diagnostic and staging procedure has been proven to significantly increase survival, compared with conventional diagnostic and staging procedures, in a pragmatic, randomised controlled trial (Navani N. et al, 2015). The instalment of EBUS will have the greatest effect on overwhelmed, suboptimally functioning national healthcare systems, by decreasing the number of required diagnostic and staging procedures, therefore reducing both treatment delays and costs. The improved selection of surgical candidates by EBUS will result in improved patient outcomes. The latest findings regarding the benefits of EBUS are outlined in this review, which, to the best of our knowledge, is the first to emphasise the impact of the procedure, both on timing and costs of lung cancer staging, as well as on survival.

Endoscopic ultrasound fine-needle aspiration by experienced pulmonologists: a cusum analysis

Endobronchial ultrasound transbronchial needle aspiration (EBUS TBNA) is an established, minimally invasive way to sample intrathoracic abnormalities. The EBUS scope can be passed into the oesophagus to perform endoscopic ultrasound with bronchoscope-guided fine-needle aspiration (EUS-B-FNA). In cases of suspected lung cancer, a combination of the two techniques is now recommended by consensus guidelines. EBUS TBNA is usually performed by pulmonologists; however, the learning curve for EUS-B-FNA, which may be performed during the same procedure, has not been described.A multicentre, observational Australian study, using prospectively collected data from three experienced pulmonologists was conducted. Cumulative sum (cusum) analysis was used to generate visual learning curves.A total of 152 target lesions were sampled in 137 patients, with an overall sensitivity for malignancy of 94.8%. The sensitivity for malignant lesions outside of the 2009 International Association for the Study of Lung Cancer lymph node map (largely intraparenchymal lesions) was 92.9%. All three operators were competent by conventional cusum criteria. There was one case of pneumothorax, and no episodes of mediastinitis or oesophageal perforation were observed.Our data suggest that experienced pulmonologists can safely and accurately perform EUS-B-FNA, with a high diagnostic sensitivity for both lymph node and non-nodal lesions.

Diagnostic performance of endobronchial ultrasound-guided mediastinal lymph node sampling in early stage non-small cell lung cancer: A prospective study

BACKGROUND AND OBJECTIVE

Standard nodal staging of lung cancer consists of positron emission tomography/computed tomography (PET/CT), followed by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) if PET/CT shows mediastinal lymphadenopathy. Sensitivity of EBUS-TBNA in patients with N0/N1 disease by PET/CT is unclear and largely based on retrospective studies. We assessed the sensitivity of EBUS-TBNA in this setting.

METHODS

We enrolled patients with proven or suspected lung cancer staged as N0/N1 by PET/CT and without metastatic disease (M0), who underwent staging EBUS-TBNA. Primary outcome was sensitivity of EBUS-TBNA compared with a composite reference standard of surgical stage or EBUS-TBNA stage if EBUS demonstrated N2/N3 disease.

RESULTS

Seventy-five patients were included in the analysis. Mean tumour size was 3.52 cm (±1.63). Fifteen of 75 patients (20%) had N2 disease. EBUS-TBNA identified six while nine were only identified at surgery. Sensitivity of EBUS-TBNA for N2 disease was 40% (95% CI: 16.3-67.7%).

CONCLUSION

A significant proportion of patients with N0/N1 disease by PET/CT had N2 disease (20%) and EBUS-TBNA identified a substantial fraction of these patients, thus improving diagnostic accuracy compared with PET/CT alone. Sensitivity of EBUS-TBNA however appears lower compared with historical data from patients with larger volume mediastinal disease. Therefore, strategies to improve EBUS-TBNA accuracy in this population should be further explored.

EUS-B-FNA vs conventional EUS-FNA for left adrenal gland analysis in lung cancer patients

INTRODUCTION

In patients with lung cancer, left adrenal glands (LAG) suspected for distant metastases (M1b) based on imaging require further evaluation for a definitive diagnosis. Tissue acquisition is regularly performed using conventional EUS-FNA. The aim of this study was to investigate the success rate of endoscopic ultrasound guided fine-needle aspiration using the EBUS scope (EUS-B-FNA) for LAG analysis.

METHODS

This is a prospective multicenter study in consecutive patients with (suspected) lung cancer and suspected mediastinal and LAG metastases. Following complete mediastinal staging using the EBUS scope (EBUS+EUS-B), the LAG was evaluated and sampled by both EUS-B (experimental procedure) and conventional EUS (current standard of care).

RESULTS

The success rate for LAG analysis (visualized, sampled and adequate tissue obtained) was 89% (39/44; 95% CI 76-95%) for EUS-B-FNA, and 93% (41/44; 95%CI 82-98%) for EUS-FNA. In the absence of metastases at EUS-B and/or EUS, surgical verification of the LAG or 6 months clinical and radiological follow-up was obtained, but missing for 5 patients. The prevalence of LAG metastases was 54% (21/39). In patients in whom LAG was seen and sampled, sensitivity for LAG metastases was at least 87% (95%CI 65-97%) for EUS-B, and at least 83% (95%CI 62-95%) for conventional EUS.

CONCLUSION

LAG analysis by EUS-B shows a similar high success rate in comparison to conventional EUS.

IMPLICATION

Both a mediastinal nodal and LAG evaluation can be adequately performed with just an EBUS scope and single endoscopist. This staging strategy is likely to reduce patient-burden and costs.