Guideline adherence of mediastinal staging of non-small cell lung cancer: A multicentre retrospective analysis

Endobronchial Ultrasound-Based Support Vector Machine Model for Differentiating between Benign and Malignant Mediastinal and Hilar Lymph Nodes

INTRODUCTION

The aim of the study was to establish an ultrasonographic radiomics machine learning model based on endobronchial ultrasound (EBUS) to assist in diagnosing benign and malignant mediastinal and hilar lymph nodes (LNs).

METHODS

The clinical and ultrasonographic image data of 197 patients were retrospectively analyzed. The radiomics features extracted by EBUS-based radiomics were analyzed by the least absolute shrinkage and selection operator. Then, we used a support vector machine (SVM) algorithm to establish an EBUS-based radiomics model. A total of 205 lesions were randomly divided into training (n = 143) and validation (n = 62) groups. The diagnostic efficiency was evaluated by receiver operating characteristic (ROC) curve analysis.

RESULTS

A total of 13 stable radiomics features with non-zero coefficients were selected. The SVM model exhibited promising performance in both groups. In the training group, the SVM model achieved an ROC area under the curve (AUC) of 0.892 (95% CI: 0.885-0.899), with an accuracy of 85.3%, sensitivity of 93.2%, and specificity of 79.8%. In the validation group, the SVM model had an ROC AUC of 0.906 (95% CI: 0.890-0.923), an accuracy of 74.2%, a sensitivity of 70.3%, and a specificity of 74.1%.

CONCLUSION

The EBUS-based radiomics model can be used to differentiate mediastinal and hilar benign and malignant LNs. The SVM model demonstrated excellent potential as a diagnostic tool in clinical practice.

Accuracy of endobronchial ultrasound-guided transbronchial needle aspiration for staging of non-small cell lung cancer

BACKGROUND

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is routinely performed to confirm a lung cancer diagnosis and/or to clinically stage disease. EBUS-TBNA findings may be used to determine whether patients can be offered potentially curative surgery. In this study, we evaluated the reporting in our service of EBUS-TBNA cytology for early-stage (operable) non-small cell lung cancer (NSCLC), focusing on diagnostic accuracy and analyzing cases with discordant cytologic and post-surgical histopathologic conclusions.

METHODS

Cytology slides and cytopathology reports of 120 NSCLC patients who had undergone EBUS-TBNA and lobectomy in our hospital system between 2015 and 2021 were retrospectively reviewed.

RESULTS

Of 290 lymph nodes (110 cases) able to be reviewed, interpretation of 48 lymph nodes was discordant with the original cytopathology report. This included 31 lymph nodes originally reported as adequate, which were found to be non-diagnostic on review. The diagnostic accuracy (benign/malignant) of lymph nodes that were sampled at EBUS-TBNA and excised at surgery was 89%. Specific examination of cases where EBUS-TBNA cytology did not reflect post-surgical findings illustrated important features and limitations of the procedure. These included potential misclassification of lymph node stations, the presence of multiple, variably involved nodes at lymph node stations, and the failure to detect small volume disease.

CONCLUSIONS

Continuous evaluation of EBUS-TBNA performance identifies technical limitations and areas of improvement for cytopathology reporting. This is increasingly important in an era where lung cancer screening is expected to increase diagnosis of early-stage disease and with the advent of novel treatments, including non-surgical management options.

Canadian Consensus Recommendations for the Management of Operable Stage II/III Non-Small-Cell Lung Cancer: Results of a Modified Delphi Process

The treatment paradigm for patients with stage II/III non-small-cell lung cancer (NSCLC) is rapidly evolving. We performed a modified Delphi process culminating at the Early-stage Lung cancer International eXpert Retreat (ELIXR23) meeting held in Montreal, Canada, in June 2023. Participants included medical and radiation oncologists, thoracic surgeons and pathologists from across Quebec. Statements relating to diagnosis and treatment paradigms in the preoperative, operative and postoperative time periods were generated and modified until all held a high level of consensus. These statements are aimed to help guide clinicians involved in the treatment of patients with stage II/III NSCLC.

Resectability in bronchogenic carcinoma: A single‑center experience

Bronchogenic carcinoma comprises >90% of primary lung tumors. The present study aimed to estimate the profile of patients with bronchogenic carcinoma and assess the cancer resectability in newly diagnosed patients. This is a single-center retrospective review conducted over a period of 5 years. A total of 800 patients with bronchogenic carcinoma were included. The diagnoses were mostly proven with either cytological examination or histopathological diagnosis. Sputum analysis, cytological examination of pleural effusion and bronchoscopic examination were performed. Lymph node biopsy, minimally invasive procedures (mediastinoscopy and video-assisted thoracoscopic surgery), tru-cut biopsy or fine-needle aspiration was used to obtain the samples for diagnosis. The masses were removed by lobectomy and pneumonectomy. The age range was between 22 and 87 years, with a mean age of 62.95 years. Males represented the predominant sex. Most of the patients were smokers or ex-smokers. The most common symptom was a cough, followed by dyspnea. Chest radiography revealed abnormal findings in 699 patients. A bronchoscopic evaluation was performed for the majority of patients (n=633). Endobronchial masses and other suggestive malignancy findings were present in 473 patients (83.1%) of the 569 who underwent fiberoptic bronchoscopy. Cytological and/or histopathological samples of 581 patients (91.8%) were positive. Small cell lung cancer (SCLC) occurred in 38 patients (4.75%) and non-SCLC was detected in 762 patients (95.25%). Lobectomy was the main surgical procedure, followed by pneumonectomy. A total of 5 patients developed postoperative complications without any mortality. In conclusion, bronchogenic carcinoma is rapidly increasing without a predilection for sex in the Iraqi population. Advanced preoperative staging and investigation tools are required to determine the rate of resectability.

Portrayal of video-assisted mediastinoscopic lymphadenectomy's range subsequent to its simultaneous use with uniportal VAT-lobectomy for left-sided NSCLC: a case-based perspective

BACKGROUND

Video-assisted mediastinoscopic lymphadenectomy (VAMLA) is the most precise approach combining staging and therapeutic interventions in non-small cell lung cancer (NSCLC). In the case of left-sided NSCLC, the likelihood of mediastinal lymph node metastases depends on the involvement of the left lung regional lymphatic network. As such, it appears obvious - at least for selected patients with mediastinal staging by either PET-CT or EBUS-TBNA ± EUS-FNA and with cN ≤ 2 - to merge VAMLA and left-sided video-assisted thoracoscopic (VAT) lobectomy for a single-stage therapeutical procedure.

CASE PRESENTATION

We present the clinical course of an 83-year-old patient following simultaneous VAMLA and VAT-lobectomy for invasive mucinous adenocarcinoma of the left upper lobe with a provisional cT3cN0cM0 stage. The patient developed a clinically relevant postoperative pneumothorax due to a persistent parenchymal air leak. CT scan revealed a substantial pneumomediastinum and showed the capability of VAMLAs range for mediastinal lymph node dissection in a unique way. Following the prompt insertion of a second chest tube, the situation was stabilized with an unremarkable further in-hospital stay. The patient remains free of tumor recurrence or distant metastases at a one-year follow-up.

CONCLUSION

Presenting this aperçu, we encourage reviving the debate on (1) precise mediastinal staging in general and (2) VAMLA's important role as a diagnostic and therapeutic tool.

Confirmatory Mediastinoscopy after Negative EBUS-TBNA for Mediastinal Staging of Lung Cancer: Systematic Review and Meta-analysis

RATIONALE

Current guidelines of non-small cell lung cancer (NSCLC) mediastinal staging recommend starting invasive staging with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). However, the indication to confirm a negative result of EBUS-TBNA by means of video-assisted mediastinoscopy (VAM) prior to resection differs in every guideline.

OBJECTIVE

Our aim was to evaluate the current evidence regarding the added value of confirmatory VAM after a negative EBUS-TBNA for mediastinal staging in patients with NSCLC.

METHODS

Systematic searches of studies on EBUS-TBNA for NSCLC mediastinal staging with or without confirmatory VAM but with surgical confirmation of negative results were conducted in accordance with PRISMA statement in PubMed, SCOPUS, Cochrane and Guidelines from 2005 through November 2021. In the meta-analysis the sensitivity of confirmatory VAM after a negative EBUS-TBNA, the sensitivity and negative predictive value (NPV) of the combination EBUS-TBNA plus confirmatory VAM, alongside the number of confirmatory VAM required to detect additional N2/3 disease (number needed to treat [NNT]), in patients with a previous negative EBUS-TBNA were estimated.

RESULTS

5412 articles were found, of which 29 studies were included. Random effects meta-analysis showed a sensitivity of 66.9% (95% CI: 55.8%-77.1%) for confirmatory VAM, and 96.7% (95% CI: 95.1%- 98%) for the combination EBUS-TBNA plus confirmatory VAM. NPV in studies with confirmatory VAM increased of 79.2% (95% CI: 71.4%-86.1%) for EBUS-TBNA alone to 91.8% (95% CI: 87.1%-95.5%) for EBUS-TBNA plus confirmatory VAM. The NNT of confirmatory VAM in patients with a previous negative EBUS-TBNA was 23.8 (95% CI: 19.3-31.2) CONCLUSIONS: Confirmatory VAM after negative EBUS-TBNA reduces the rate of unforeseen N2/3 disease, but with a high NNT, and should be recommended only to certain cases yet to be defined.

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.

Patients' Preferences Regarding Invasive Mediastinal Nodal Staging of Resectable Lung Cancer

BACKGROUND

Variability in practice and ongoing debate on optimal invasive mediastinal staging of patients with resectable non-small cell lung cancer (NSCLC) are widely described in the literature. Patients' preferences on this topic have, however, been underexposed so far.

METHODS

An internet-based questionnaire was distributed among MEDIASTrial participants (NTR6528, randomization of patients to mediastinoscopy or not in the case of negative endosonography). Literature, expert opinion and patient interviews resulted in five attributes: the risk of a futile lung resection (oncologically futile in case of unforeseen N2 disease), the length of the staging period, resection of the primary tumor, complications of staging procedures and the mediastinoscopy scar. The relative importance (RI) of each attribute was assessed by using adaptive conjoint analysis and hierarchical Bayes estimation. A treatment trade-off was used to examine the acceptable proportion of avoided futile lung resections to cover the burden of confirmatory mediastinoscopy.

RESULTS

Ninety-seven patients completed the questionnaire (57%). The length of the staging period was significantly the most important attribute (RI 26.24; 95% CI: 25.05-27.43), followed by the risk of a futile surgical lung resection (RI 23.44; 95% CI: 22.28-24.60) and resection of the primary tumor (RI 22.21; 95% CI: 21.09-23.33). Avoidance of 7% (IQR 1- >14%) futile lung resections would cover the burden of confirmatory mediastinoscopy, with a dichotomy among patients always (39%) or never (38%) willing to undergo confirmatory mediastinoscopy after N2 and N3-negative endosonography.

CONCLUSION

Although a strong dichotomy among patients always or never willing to undergo confirmatory mediastinoscopy was found, the length of the staging period was the most important attribute in invasive mediastinal staging according to patients with resectable NSCLC.

TRIAL REGISTRATION

Not applicable.

Diagnostic utility of metabolic parameters on FDG PET/CT for lymph node metastasis in patients with cN2 non-small cell lung cancer

Background

The aim of this study was to assess the diagnostic utility of metabolic parameters on fluorine-18-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET)/computed tomography (CT) for predicting lymph node (LN) metastasis in patients with cN2 non-small cell lung cancer (NSCLC).

Methods

We retrospectively reviewed patients who underwent surgery for cN2 NSCLC between 2007 and 2020. Those who had clinically diagnosed positive hilar and mediastinal LNs by routine CT and PET/CT imaging were investigated. To measure the metabolic parameters of LNs, the data according to maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and LN-to-primary tumor ratio of SUVmax (LPR) were examined. The diagnosis of each retrieved LN was confirmed based on histopathological examination of surgical tissue specimens. Receiver operating characteristics (ROC) curves with area under the curve (AUC) calculations and multivariate analysis by logistic regression were performed.

Results

Forty-five patients with 84 clinically diagnosed positive hilar or mediastinal LNs were enrolled in the present study. Of the 84 LNs, 63 LNs were pathologically proven as positive (75%). The SUVmax, MTV, TLG, and LPR of LN metastasis were significantly higher than those of benign nodes. In the ROC analysis, the AUC value of LPR [AUC, 0.776; 95% confidence interval (CI), 0.640–0.913] was higher than that of LN SUVmax (AUC, 0.753; 95% CI, 0.626–0.880) or LN TLG3.5 (AUC, 0.746; 95% CI, 0.607–0.885). Using the optimal LPR cutoff value of 0.47, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 84.1, 66.7, 88.3, 58.3, and 79.8%, respectively. Multivariate analysis by logistic regression showed that LPR was an independent predictor for LN metastasis (odds ratio, 6.45; 95% CI, 1.785–23.301; P = 0.004). In the subgroup analysis of adenocarcinoma patients (n = 18; 32 LNs), TLG3.5 was a better predictor (AUC, 0.816; 95% CI, 0.639–0.985) than LPR (AUC, 0.792; 95% CI, 0.599–0.986) or LN SUVmax (AUC, 0.792; 95% CI, 0.625–0.959).

Conclusions

Our findings suggest that LPR on FDG-PET is a useful predictor for LN metastasis in patients with cN2 NSCLC. TLG can be a good predictor for LN metastasis in patients with adenocarcinoma.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08688-6.

Performance insights of endobronchial ultrasonography (EBUS) and mediastinoscopy for mediastinal lymph node staging in lung cancer

INTRODUCTION

Endobronchial Ultrasonography (EBUS) and mediastinoscopy are used for mediastinal lymph node staging in patients with suspected non-small cell lung carcinoma (NSCLC). In our hospital, confirmatory mediastinoscopy has been largely abandoned, which may reduce the number of surgical interventions and health care costs. This study provides insight into EBUS and mediastinoscopy performance in patients with proven NSCLC from January 2007 until January 2019.

METHODS

This is a single-centre, retrospective study, evaluating unforeseen N2 rates, negative predictive value and survival, providing insight into the diagnostic yield of EBUS and mediastinoscopy. Surgical lung resection with lymph node dissection was used as reference.

RESULTS

A total of 418 patients with proven NSCLC after lung resection (mean age: 66 years; 61 % male) and 118 patients who underwent mediastinoscopy, have been included in the study. The overall prevalence of N2 metastases after lung resection was 10.5 %. The percentage of unforeseen N2 cases after negative EBUS was 14.5 %, and 14.3 % after negative mediastinoscopy. Over the past nine years, none of the confirmatory mediastinoscopies were tumor positive after negative EBUS results. The median survival in patients with surgically confirmed N2 metastases was 33 months, compared to 23 months in patients with EBUS/mediastinoscopy-proven N2 metastases.

CONCLUSION

Despite optimisation of mediastinal staging procedures, it remains difficult to identify all patients with N2 metastases in the workup of NSCLC. In our institute, confirmatory mediastinoscopy has no added value after tumor-negative EBUS procedures, and has been abandoned as standard procedure.

Oncological outcomes of unsuspected pN2 in patients with non-small-cell lung cancer: a systematic review and meta-analysis

OBJECTIVES

Optimal treatment of stage IIIA (N2) non-small-cell lung cancer (NSCLC) is controversial. Guidelines advise induction therapy before surgical resection. A proportion of patients with cN0 NSCLC are postoperatively upstaged due to unsuspected N2 disease. Survival of unsuspected N2 NSCLC treated with surgery varies and technical feasibility of video-assisted thoracic surgery (VATS) is unknown. The purpose of this study was to assess prevalence and survival of unsuspected N2 NSCLC treated with thoracotomy or VATS.

METHODS

A systematic review and meta-analysis was performed of all available literatures through Pubmed, Cochrane, EMBASE, Web of Science, Trials registries and System for Information on Grey Literature (SIGLE) from 2000 to 2019. Outcomes of interest were prevalence, overall survival (OS) and disease-free survival of unsuspected N2 NSCLC. Secondary outcomes were number of harvested lymph nodes, postoperative complications and survival of unsuspected N2 NSCLC treated with VATS.

RESULTS

Seventeen studies with patients with clinical stage N0-1 and unsuspected pN2 NSCLC were included. Prevalence of unsuspected pN2 was 8.6%. Three- and 5-year OS was 58% [95% confidence interval (CI) 37-78%) (N = 4337] and 35% (95% CI 28-43%) (N = 4337). Three- and 5-y ear disease-free survival was 48% (95% CI 30-66%) (N = 109) and 35% (95% CI 24-46%) (N = 517). VATS resulted in a low complication rate with similar 5-year OS as thoracotomy.

CONCLUSIONS

In patients with cN0-1 NSCLC, a minority has unsuspected pN2 NSCLC. Even for these patients, 5-year OS and disease-free survival are reasonable. VATS with adequate lymph node dissection is the treatment of choice when in experienced hands. Adjuvant therapy should be provided in absence of relevant comorbidity.

Occult lymph node metastases in clinical N0/N1 NSCLC; A single center in-depth analysis

OBJECTIVES

Lymph node staging in patients with non-small cell lung cancer is crucial for determining prognosis and treatment. Our objective was to evaluate the clinical- to pathological agreement of guideline-concordant nodal staging in patients with resectable NSCLC and assess occurrence and distribution of occult lymph node metastases (OLM).

MATERIALS AND METHODS

In a retrospective single center cohort study (n = 390), we analyzed all surgically treated NSCLC patients from January 2015 until April 2019. Patients were classified into sub-groups (1) mediastinal staging by PET-CT/CT-scan (IMAGE-group) or (2) invasive staging by endobronchial ultrasound and mediastinoscopy (INVAS-group). Agreement between final clinical (cN) and pathological nodal stage (pN) and the presence and location of OLM are analyzed.

RESULTS

Agreement between cN- and pN-stage was 86.3 % in the IMAGE-group (n = 117) and 50.9 % in the INVAS-group (n = 167). Occult N1 disease was found in 33 patients (16.6 % in cN0) of which 52 % occurred in LN-regions 12-14. Occult N2 disease was found in 20 cases (6.5 % in cN0 and 12.7 % in cN1). Combined, 23.1 % of all pre-operatively cN0-staged patients (n = 46/199) had OLM (pN+), of which 12.1 % (24/199) had metastases in regions 5-6 and/or 12-14. Of all patients with OLM, 50.0 % (23/46) had primary tumors ≤30 mm.

CONCLUSION

OLM are frequently identified in clinically N0/N1 NSCLC, also in tumors <3 cm, and often in regions beyond reach of current staging techniques. These findings should be addressed when non-surgical treatment or sub-lobar resections are considered for early stage lung cancer.

Cost-effectiveness of endoscopic mediastinal staging

Lung cancer is the first cause of cancer-related mortality. Mediastinal staging has a main role in the definition of the therapeutic strategy in early-stage and locally-advanced non-small cell lung cancer (NSCLC). Non-invasive mediastinal staging with CT or PET imaging has relatively limited accuracy, and nodal biopsy may be required to reach adequate staging results. In the last two decades endoscopic techniques have been increasingly used in the field of mediastinal staging thanks to a reduced invasiveness and to the possibility of obtaining a more thorough assessment in comparison with surgical techniques. However, the ideal staging strategy is still a matter for debate, particularly considering the cost-effectiveness of the different approaches. Complication-rate, costs, impact on quality of life, time delay to treatment and survival of the different staging techniques still have to be analyzed in detail. Other issues to be discussed are the optimal combination of staging approaches and the influence of factors as the prevalence of nodal disease on the cost-effectiveness of the different methods. Future issues of invasive staging concern the possibility of extending the definition of nodal status to N1 intrapulmonary nodes, in the light of the development of new oncological and surgical therapeutic approaches.

Results of neoadjuvant chemo(radio)therapy and resection for stage IIIA non-small cell lung cancer in The Netherlands

Introduction: Concurrent chemoradiotherapy remains the main treatment strategy for patients with stage IIIA non-small cell lung cancer (NSCLC); stage cT3N1 or cT4N0-1 may be eligible for surgery and potentially resectable stage IIIA (N2) NSCLC for neoadjuvant therapy followed by resection. We evaluated treatment patterns and outcomes of patients with stage IIIA NSCLC in The Netherlands.Material and Methods: Primary treatment data of patients with clinically staged IIIA NSCLC between 2010 and 2016 were extracted from The Netherlands Cancer Registry. Patient characteristics were tabulated and 5-year overall survival (OS) was calculated and reported.Results: In total, 9,591 patients were diagnosed with stage IIIA NSCLC. Of these patients, 41.3% were treated with chemoradiotherapy, 11.6% by upfront surgery and 428 patients (4.5%) received neoadjuvant treatment followed by resection. The 5-year OS was 26% after chemoradiotherapy, 40% after upfront surgery and 54% after neoadjuvant treatment followed by resection. Clinical over staging was seen in 42.3% of the patients that were operated without neoadjuvant therapy.Conclusion: In The Netherlands, between 2010 and 2016, 4.5% of patients with stage IIIA NSCLC were selected for treatment with neoadjuvant therapy followed by resection. The 5-year OS in these patients exceeded 50%. However, the outcome might be overestimated due to clinical over staging.

Adherence to the mediastinal staging guideline and unforeseen N2 disease in patients with resectable non-small cell lung cancer: Nationwide results from the Dutch Lung Cancer Audit - Surgery

OBJECTIVES

Invasive mediastinal staging is advised by guidelines in patients with resectable non-small cell lung cancer (NSCLC) and suspicious lymph nodes (cN1-3) or for central, FDG-non-avid or peripheral tumours >3 cm. Our objective was to assess current guideline adherence and consequent unforeseen N2 disease (uN2) in NSCLC patients having various indications for mediastinal staging.

MATERIALS AND METHODS

We analysed the Dutch Lung Cancer Audit - Surgery data of all patients who underwent a primary lung resection with lymph node dissection for NSCLC in 2017-2018. Based on the 2015 ESTS-ERS-ESGE guideline we assessed the use of initial endosonography and confirmatory mediastinoscopy as well as uN2 rates.

RESULTS

A total of 2238 patients were analysed. 43 % (95 %-CI: 41-45) underwent initial endosonography followed by a confirmatory mediastinoscopy in 44 % (95 %-CI:40-47) of them, resulting in a 19 % (95 %-CI: 17-20) rate of properly staged patient according to the guidelines. uN2 was demonstrated in 12.5 % (95 %-CI: 9.7-16.0) of correctly staged patients compared to 10.9 % (95 %-CI: 9.6-12.4) who were not (p = .36). The highest uN2 rate was found in cN1-3 patients who were not staged (23.0 %, 95 %-CI: 16.4-31.2) compared to 13.0 % (95 %-CI: 9.7-17.1) who were (p = .01).

CONCLUSION

Guideline adherence in Dutch NSCLC patients with an indication for invasive mediastinal staging is poor. The highest uN2 rate was found in unstaged cN1-3 patients, suggesting that this subgroup may benefit from an appropriate staging conform guidelines.