Outcomes of Mediastinoscopy and Surgery with or without Neoadjuvant Therapy in Patients with Non-small Cell Lung Cancer Who are N2 Negative on Positron Emission Tomography and Computed Tomography

Clinical Effect of Endosonography on Overall Survival in Patients with Radiological N1 Non-Small Cell Lung Cancer

PURPOSE

It is unclear whether performing endosonography first in non-small cell lung cancer (NSCLC) patients with radiological N1 (rN1) has any advantages over surgery without nodal staging. We aimed to compare surgery without endosonography to performing endosonography first in rN1 on the overall survival (OS) of patients with NSCLC.

MATERIALS AND METHODS

This is a retrospective analysis of patients with rN1 NSCLC between 2013 and 2019. Patients were divided into 'no endosonography' and 'endosonography first' groups. We investigated the effect of nodal staging through endosonography on OS using propensity score matching (PSM) and multivariable Cox proportional hazard regression analysis.

RESULTS

In the no endosonography group, pathologic N2 occurred in 23.0% of patients. In the endosonography first group, endosonographic N2 and N3 occurred in 8.6% and 1.6% of patients, respectively. Additionally, 51 patients were pathologic N2 among 249 patients who underwent surgery and mediastinal lymph node dissection (MLND) in endosonography first group. After PSM, the 5-year OSs were 68.1% and 70.6% in the no endosonography and endosonography first groups, respectively. However, the 5-year OS was 80.2% in the subgroup who underwent surgery and MLND of the endosonography first group. Moreover, in patients receiving surgical resection with MLND, the endosonography first group tended to have a better OS than the no endosonography group in adjusted analysis using various models.

CONCLUSION

In rN1 NSCLC, preoperative endosonography shows better OS than surgery without endosonography. For patients with rN1 NSCLC who are candidates for surgery, preoperative endosonography may help improve survival through patient selection.

True Prevalence of Unforeseen N2 Disease in NSCLC: A Systematic Review + Meta-Analysis

Patients with unforeseen N2 (uN2) disease are traditionally considered to have an unfavorable prognosis. As preoperative and intraoperative mediastinal staging improved over time, the prevalence of uN2 changed. In this review, the current evidence on uN2 disease and its prevalence will be evaluated. A systematic literature search was performed to identify all studies or completed, published trials that included uN2 disease until 6 April 2023, without language restrictions. The Newcastle-Ottawa Scale (NOS) was used to score the included papers. A total of 512 articles were initially identified, of which a total of 22 studies met the predefined inclusion criteria. Despite adequate mediastinal staging, the pooled prevalence of true unforeseen pN2 (9387 patients) was 7.97% (95% CI 6.67-9.27%), with a pooled OS after five years (892 patients) of 44% (95% CI 31-58%). Substantial heterogeneity regarding the characteristics of uN2 disease limited our meta-analysis considerably. However, it seems patients with uN2 disease represent a subcategory with a similar prognosis to stage IIb if complete surgical resection can be achieved, and the contribution of adjuvant therapy is to be further explored.

Lung cancer with PET/CT-defined occult nodal metastasis yields favourable prognosis and benefits from adjuvant therapy: a multicentre study

PURPOSE

To investigate the surgical prognosis and efficacy of adjuvant therapy in non-small cell lung cancer (NSCLC) with occult lymph node metastasis (ONM) defined by positron emission tomography/computed tomography (PET/CT).

METHODS

A total of 3537 NSCLC patients receiving surgical resection were included in this study. The prognosis between patients with ONM and evident nodal metastasis, ONM patients with and without adjuvant therapy was compared, respectively.

RESULTS

ONM was associated with significantly better prognosis than evident nodal metastasis whether for patients with N1 (5-year OS: 56.8% versus 52.3%, adjusted p value = 0.267; 5-year RFS: 44.7% versus 33.2%, adjusted p value = 0.031) or N2 metastasis (5-year OS: 42.8% versus 32.3%, adjusted p value = 0.010; 5-year RFS: 31.3% versus 21.6%, adjusted p value = 0.025). In ONM population, patients receiving adjuvant therapy yielded better prognosis comparing to those without adjuvant therapy (5-year OS: 50.1% versus 33.5%, adjusted p value < 0.001; 5-year RFS: 38.4% versus 22.1%, adjusted p value < 0.001).

CONCLUSIONS

ONM defined by PET/CT identifies a unique clinical subtype of lung cancer, ONM is a favorable prognostic factor whether for pathological N1 or N2 NSCLC and adjuvant therapy could provide additional survival benefits for ONM patients.

Utility of Elastography for Differentiating Malignant and Benign Lymph Nodes During EBUS-TBNA: A Systematic Review and Meta-analysis

BACKGROUND

Ultrasound elastography noninvasively estimates tissue hardness. Studies have evaluated elastography for differentiating malignant from benign lymph nodes during endobronchial ultrasound-guided transbronchial needle aspiration. Several methods of performing elastography are described with variable diagnostic accuracy.

METHODS

The aim of this study was to evaluate endobronchial ultrasound-guided elastography in differentiating malignant from benign mediastinal lymphadenopathy. We performed a systematic search of the PubMed and Embase databases to extract the relevant studies. A diagnostic accuracy meta-analysis was carried out to calculate the pooled sensitivity and specificity [with 95% confidence intervals (CIs)], and positive and negative likelihood ratios of elastography.

RESULTS

After a systematic search, 20 studies (1600 patients, 2712 nodes) were selected. The pooled sensitivity and specificity of elastography were 0.90 (95% CI, 0.84-0.94) and 0.79 (95% CI, 0.73-0.84), respectively. The summary receiver operating curve demonstrated an area under the curve for elastography of 0.90 (0.88-0.93). The positive and negative likelihood ratios and the diagnostic odds ratio were 4.3 (95% CI, 3.3-5.5), 0.12 (95% CI, 0.07-0.20), and 35 (95% CI, 19-63), respectively. Of the most commonly described methods, the color classification method (type 3 malignant vs. type 1 benign) demonstrated the highest area under the curve of 0.91 (0.88-0.93). There was significant heterogeneity and publication bias. Subgroup analyses indicated no significant difference between the sensitivity and specificity of quantitative and qualitative elastography methods.

CONCLUSIONS

Ultrasound elastography is useful in differentiating malignant and benign lymph nodes during endobronchial ultrasound-guided transbronchial needle aspiration. However, elastography does not replace the requirement of lymph node aspiration.

Adjuvant therapy in stage IIIA-N2 non-small cell lung cancer after neoadjuvant concurrent chemoradiotherapy followed by surgery

Background

This study aimed to determine whether adjuvant therapy improves survival in patients with stage IIIA-N2 non-small cell lung cancer (NSCLC) after neoadjuvant concurrent chemoradiotherapy (CCRT) followed by surgery.

Methods

We retrospectively reviewed 467 consecutive patients with stage IIIA-N2 NSCLC who received neoadjuvant CCRT followed by surgery between 2004 and 2013. From these, we identified 398 eligible patients and their clinical outcomes were compared according to whether adjuvant therapy was provided.

Results

In total, 296 patients (74%) received adjuvant therapy consisting of chemotherapy alone (n=71) radiotherapy alone (n=118) and both chemotherapy and radiotherapy (n=107). Adjuvant therapy was not given to remaining 102 patients. Patients who receiving adjuvant therapy were significantly younger (P=0.001), and predominantly male (P=0.014) compared to patients who did not receive adjuvant therapy. Regarding to the pathologic response, the adjuvant therapy group had a significantly poor pathologic response. However, the 5-year overall survival (OS) rate did not significantly differ between the groups (adjuvant therapy group, 52.9%; no adjuvant therapy group, 54.9%; P=0.369). After adjusting for age, sex, type of operation, cell type and yp stage, adjuvant therapy was significantly associated with better OS (hazard ratio =0.59; 95% CI, 0.38–0.92; P=0.019) and disease free survival (hazard ratio =0.62; 95% CI, 0.44–0.87; P=0.006).

Conclusions

Our data indicate that adjuvant therapy is more often given to patients with poor pathologic findings. Adjuvant treatment after trimodal therapy is a significant predictor of survival after adjustment of clinical variables.

The utility of endosonography for mediastinal staging of non-small cell lung cancer in patients with radiological N0 disease

OBJECTIVES

Recent practice guidelines recommend endosonography for patients with radiological N0 non-small cell lung cancer (NSCLC) when the primary tumors are >3 cm in diameter or centrally located. However, any role for endosonography remains debatable. We evaluated the utility of endosonography in patients with radiological N0 NSCLC based on tumor centrality, diameter and histology.

MATERIALS AND METHODS

Patients who underwent staging endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) with or without transesophageal bronchoscopic ultrasound-guided fine needle aspiration (EUS-B-FNA) for radiological N0 NSCLC were retrospectively investigated using prospectively collected endosonography data. The radiological N0 stage was defined by node diameter as evident on computed tomography images and ¹⁸F-FDG uptake using integrated positron emission tomography-computed tomography.

RESULTS

In total of 168 patients, the median size of the primary tumor was 39 mm, and 41 % of tumors were centrally located. The prevalence of occult mediastinal metastases was 11.3 % (19/168). The sensitivity of endosonography in terms of diagnosing occult mediastinal metastases was only 47 % (9/19); 6 of 10 patients with false-negative endosonography data exhibited metastases in accessible nodes. The diagnostic performance of endosonography did not differ by tumor centrality or diameter. Patients with adenocarcinoma histology showed higher prevalence of occult mediastinal metastases and higher false-negative results in endosonography compared with those with non-adenocarcinoma histology.

CONCLUSION

Not all patients with radiological N0 NSCLC benefit from endosonography, given the low prevalence of occult mediastinal metastases and the poor sensitivity of endosonography in this population. The strategy of invasive mediastinal staging needs to be tailored considering the histology of the tumor in this population.

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.

Which definition of a central tumour is more predictive of occult mediastinal metastasis in nonsmall cell lung cancer patients with radiological N0 disease?

Background

Guidelines recommend invasive mediastinal staging for centrally located tumours, even in radiological N0 nonsmall cell lung cancer (NSCLC). However, there is no uniform definition of a central tumour that is more predictive of occult mediastinal metastasis.

Methods

A total of 1337 consecutive patients with radiological N0 disease underwent invasive mediastinal staging. Tumours were categorised into central and peripheral by seven different definitions.

Results

About 7% (93 out of 1337) of patients had occult N2 disease, and they had significantly larger tumour size and more solid tumours on computed tomography. After adjustment for patient- and tumour-related characteristics, only the central tumour definition of the inner one-third of the hemithorax adopted by drawing concentric lines arising from the midline significantly predicted occult N2 disease (adjusted OR 2.13, 95% CI 1.17–3.87; p=0.013). This association was maintained after excluding patients with pure ground-glass nodules (adjusted OR 2.54, 95% CI 1.37–4.71; p=0.003) or only including those with solid tumours (adjusted OR 2.30, 95% CI 1.08–4.88; p=0.030).

Conclusions

We suggest that a central tumour should be defined using the inner one-third of the hemithorax adopted by drawing concentric lines from the midline. This is particularly useful for predicting occult N2 disease in patients with NSCLC.

Central tumours defined as located in the inner one-third of the hemithorax adopted by drawing concentric lines from the midline are associated with occult mediastinal metastasis in patients with NSCLC and radiological N0 diseasehttp://ow.ly/scg630nbRmY

Semi-quantitative Analysis of EBUS Elastography as a Feasible Approach in Diagnosing Mediastinal and Hilar Lymph Nodes of Lung Cancer Patients

This study aimed to semi-quantitatively evaluate the elastographic imaging color distribution of mediastinal and hilar lymph nodes (LNs), and explored its utility in helping define malignant and benign LNs for lung cancer patients. We prospectively collected patients who underwent preoperative mediastinal staging of suspected lung cancer by EBUS-TBNA. We analyzed the elastography color distribution of each LN and calculated the blue color proportion (BCP). The LN elastographic patterns were compared with the final EBUS-TBNA pathological results. A receiver operating characteristic (ROC) curve was constructed to evaluate the diagnostic value of BCP. We sampled and analyzed 79 LNs from 60 patients. The average BCP in malignant LNs was remarkably higher than that in benign LNs (57.1% versus 30.8%, P < 0.001). The area under the ROC curve (AUC) for the BCP was 0.86 (95% CI: 0.78–0.94). The best cutoff BCP for differentiating between benign and malignant LNs was determined as 36.7%. All the 16 LNs (20.3%) with a BCP lower than 27.9% were diagnosed as benign tissues. Our study suggests that elastography is a feasible technique that may safely help to predict LN metastasis during EBUS-TBNA. We found a clear BCP cutoff value to help define positive and negative LNs.

Pre- and postoperative care for stage I-III NSCLC: Which quality of care indicators are evidence-based?

Identification of evidenced-based Quality of Care (QoC) indicators for lung cancer care is essential to quality improvement. The aim of this review was to identify evidence-based quality indicators for the pre- and postoperative care of stage I-III Non Small Cell Lung Cancer (NSCLC) provided by the lung physician. To obtain these indicators, a search in PubMed, Embase and the Cochrane library database was performed. English literature published between 1980 and 2012 was included and search terms regarding 'lung neoplasms', 'quality of care', 'pathology', 'diagnostic methods', 'preoperative and postoperative treatment' were used. The potential indicators were categorized as structure, process or outcome measures and the indicators supported by literature with high evidence level were selected. Five QoC indicators were identified. The use of the positron emission tomography-computed tomography (PET-CT) results in more accurate mediastinal staging compared to the CT scan. Endoscopic Ultrasound-Fine Needle Aspiration and Endobronchial Ultrasound-Fine Needle Aspiration are sensitive diagnostic tools for mediastinal staging and reduce futile thoracotomies. Pathological conformation of lung cancer can best be obtained by a combination of cytological and histological diagnostics used during bronchoscopy. For patients with clinical stage III NSCLC, preoperative multimodality treatment (i.e. preoperative chemoradiation) results in superior survival and increased mediastinal downstaging compared to single modality treatment (i.e. preoperative chemotherapy or radiotherapy). After surgery, the addition of chemotherapy results in a significant survival benefit for patients with pathological stage II and III NSCLC. These five QoC indicators can be used for benchmarking and ultimately quality improvement of lung cancer care.

Evaluation of lymph node metastasis in lung cancer: who is the chief justice?

Accurate determination of the diagnosis and the stage of lung cancer play a critical role to ensure that patients are provided the optimal treatment. However, the process is usually beyond complex. Early studies have suggested lymph nodes (LNs) >1.0 cm in size on computed tomography (CT) are considered as metastatic nodes, while the sensitivity of this criterion is not satisfied. Subsequently, positron emission tomography-computed tomography (PET-CT) was shown to be superior to CT alone on assessment of nodal involvement and was widely used to estimate suitability for resection with curative intent, but the dependability also remains controversial. Furthermore, transbronchial needle aspiration (TBNA) with and without endobronchial ultrasound (EBUS), as a well-accepted minimally invasive approach for LN biopsy, has been documented as an efficient tool in evaluation of CT and PET-CT negative LNs. Additionally, radiographic features including ground-glass/solid nodules ratio, referring as imaging biomarker, were indicated to be correlated with metastasis. Hence, we highlight the importance of comprehensive estimation of mediastinal and hilar LNs, and we suggested the judgment of LNs by radiographic tools alone might not be reliable and TBNA is indispensable in certain circumstances.

Surgery following neoadjuvant chemotherapy for non-small-cell lung cancer patients with unexpected persistent pathological N2 disease

Patients with mediastinal lymph node (LN) downstaging following neoadjuvant chemotherapy exhibit improved outcomes compared with patients with persistent N2 disease. The aim of this study was to compare clinicopathological characteristics and survival between patients with unexpected and expected persistent N2 disease following surgery for non-small-cell lung cancer (NSCLC). This retrospective analysis included 348 patients with NSCLC who underwent surgery following chemotherapy at the Shanghai Pulmonary Hospital, Tongji University School of Medicine, between 1995 and 2012. According to the results of the imaging examinations and postoperative pathology, the patients were divided into three groups, namely groups I (nodal downstaging, pN0-1), II (expected persistent N2 disease) and III (unexpected persistent N2 disease). The rates of overall survival (OS) and disease-free survival (DFS) were estimated by the Kaplan-Meier method. Univariate and multivariate analyses were performed to identify the independent risk factors for OS and DFS. The mortality rate was 1.1% during the postoperative period. Perioperative complications occurred in 45 patients (12.9%). The 5-year OS rate was 32.2, 6.3 and 25.9% in groups I, II and III, respectively (group I vs. III, P=0.023; and group III vs. II, P<0.001). The 5-year DFS rate was 30.1, 5.1 and 22.4% in groups I, II and III, respectively (group I vs. III, P=0.012; and group III vs. II, P<0.001). Grouping, predicted forced expiratory volume in 1 sec, N downstaging and skip N2 metastasis were identified as independent predictive factors associated with OS, whereas the independent risk factors associated with DFS were grouping and N downstaging. Patients with unexpected persistent N2 disease exhibited better survival compared with those with expected persistent N2 disease. Surgery following chemotherapy remains the optimal approach for a proportion of patients with persistent N2 disease.

Endobronchial ultrasound versus mediastinoscopy for mediastinal nodal staging of non-small-cell lung cancer

INTRODUCTION

Correct mediastinal staging is critical for determination of the most appropriate management strategy in patients with non-small-cell lung cancer (NSCLC). The purpose of this study was to compare the diagnostic performance of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) with that of mediastinoscopy in patients with NSCLC.

METHODS

A prospective trial was conducted in a tertiary referral center in Korea. Patients with histologically proven NSCLC and suspicion for N1, N2, or N3 metastasis were enrolled. Each patient underwent EBUS-TBNA followed by mediastinoscopy. Surgical resection and complete lymph node dissection were conducted in patients for whom no evidence of mediastinal metastasis was apparent after mediastinoscopy.

RESULTS

In total, 138 patients underwent EBUS-TBNA and 127 completed both EBUS-TBNA and mediastinoscopy. N2/N3 disease was confirmed in 59.1% of the patients. The diagnostic sensitivity, specificity, accuracy, positive predictive value, and negative predictive value (NPV) of EBUS-TBNA on a per-person analysis were 88.0%, 100%, 92.9%, 100%, and 85.2%, respectively. The diagnostic sensitivity, specificity, accuracy, positive predictive value, and NPV of mediastinoscopy on a per-person analysis were 81.3%, 100%, 89.0%, 100%, and 78.8%, respectively. Significant differences in the sensitivity, accuracy, and NPV were evident between EBUS-TBNA and mediastinoscopy (p < 0.005).

CONCLUSIONS

EBUS-TBNA was superior to mediastinoscopy in terms of its diagnostic performance for mediastinal staging of cN1-3 NSCLC. Because EBUS-TBNA is both less invasive and affords superior diagnostic sensitivity, it should be the first-line procedure performed in patients with NSCLC.

Diagnosing and staging lung cancer involving the mediastinum

The purpose of this article is to provide an update on evidence-based methods for mediastinal staging in patients with lung cancer. This is a review of the recently published studies and a summary of relevant guidelines addressing the role of CT scan, PET scan, endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA), and mediastinoscopy as pertinent to lung cancer staging and restaging. The focus is on how these diagnostic methods fit into the best algorithm for patients with chest imaging abnormalities suspected of malignant disease. Several studies, meta-analyses, and systematic reviews specifically targeted the role of PET scan, EBUS-TBNA, and mediastinoscopy for detecting mediastinal lymph node involvement in patients suffering from lung cancer. Based on the recommendations from the currently published guidelines, algorithms of care are proposed for staging and restaging of the mediastinum.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Endobronchial ultrasonography for positron emission tomography and computed tomography-negative lymph node staging in non-small cell lung cancer

BACKGROUND

Integrated positron emission tomography (PET) with computed tomography (CT) is a useful modality to investigate lymph node metastases for non-small cell lung cancer, but is less sensitive for normal-sized lymph nodes. We sometimes encounter cases with radiologically normal lymph nodes and unsuspected mediastinal metastases detected by endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). However, few studies have investigated staging in patients with radiologically normal mediastina, and the accuracy of EBUS-TBNA staging for radiologically normal mediastina and hila is unclear.

METHODS

This study was a retrospective, single-institution review of a prospectively maintained database at Chiba Cancer Center between May 1, 2008, and September 1, 2013. We analyzed 113 non-small cell lung cancer patients with both CT-negative and PET/CT-negative lymph nodes (N0) in preoperative nodal staging performed by EBUS-TBNA. After preoperative staging was performed, patients with either N0 or N1 clinical staging underwent surgery. Final N factors were determined by mediastinal lymphadenectomy.

RESULTS

In our study, the overall rate of N2 disease was 17.6% (20 of 113). For nodal staging by EBUS-TBNA, the sensitivity, specificity, negative predictive value, and diagnostic accuracy were 35.0% (7 of 20), 100% (93 of 93), 87.7% (93 of 106), and 88.4% (100 of 113), respectively. There were no severe complications from EBUS-TBNA staging.

CONCLUSIONS

The overall rate of unsuspected N2 was not low. EBUS-TBNA was accurate and feasible for preoperative mediastinal nodal staging of non-small cell lung cancer with both CT-negative and PET/CT-negative lymph nodes. The sensitivity of EBUS-TBNA for radiologically normal mediastina and hila was low. Further investigations are required.

Prognosis of unexpected and expected pathologic N1 non-small cell lung cancer

BACKGROUND

This study was undertaken to compare clinicopathologic features and survival between patients with unexpected N1 (clinical N0-pathologic N1) and expected N1 disease (clinical N1-pathologic N1) after operation for non-small cell lung cancer.

METHODS

From 2003 to 2009, 305 patients who were found to have pathologic N1 disease after complete resection were retrospectively analyzed. Among these, 177 patients had negative findings for both computed tomography (CT) and positron emission tomography (PET)/CT (group cN0). Sixty-eight patients had negative CT and positive PET/CT or positive CT and negative PET/CT findings (group cN0-1). Sixty patients had positive findings for both CT and PET/CT (group cN1).

RESULTS

Patients in the cN1 group had larger tumors (p<0.001), greater pathologic T stage (p=0.018), and greater percentage of squamous cell carcinoma (p<0.001) than did those in the other groups. Patients in the cN1 group had a greater number of positive N1 lymph nodes (p=0.004) and more frequent extracapsular nodal invasion (p<0.001). The 5-year overall survival was 66%, 63%, and 58% in groups cN0, cN0-1, and cN1, respectively (cN0 vs cN0-1, p=0.958; cN0 vs cN1, p=0.038). The 5-year disease-free survival was 54%, 52%, and 39% in groups cN0, cN0-1, and cN1, respectively (cN0 vs cN0-1, p=0.862; cN0 vs cN1, p=0.01).

CONCLUSIONS

Patients with unexpected N1 disease showed better survival than did those with expected N1 disease, which seemed to be related to the pathologically minimal extent of the primary tumor and nodal involvement.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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