The high-risk features and effect of postoperative radiotherapy on survival for patients with surgically treated stage IIIA-N2 non-small cell lung cancer

OBJECTIVES

Although postoperative radiotherapy (PORT) could reduce the incidence of local recurrence in patients with IIIA-N2 non-small cell lung cancer (NSCLC), the role of PORT on survival in patients with surgically treated stage IIIA-N2 NSCLC remains controversial. Therefore, this study was designed to evaluate the effect of PORT on survival for patients with surgically treated stage IIIA-N2 NSCLC.

MATERIALS AND METHODS

This study population was chosen from the Surveillance, Epidemiology, and End Results database. The Cox proportional hazards regression analysis was used to determine significant contributors to overall survival (OS) and cancer special survival (CSS) outcomes. To balance baseline characteristics between the non-PORT group and PORT group, propensity score matching (PSM) with 1:1 propensity nearest-neighbor match by 0.001 matching tolerance was conducted by R software. Furthermore, a Kaplan-Meier curve was used to visualize the OS and CSS between the PORT group and non-PORT group survival probability.

RESULTS

Of all evaluated cases, 4511 with IIIA-N2 NSCLC were eligible for inclusion, of which 1920 were enrolled into the PORT group. On univariate analysis and multivariate analysis, sex, age, year of diagnosis, race, histologic type, T stage, PORT, use of chemotherapy, and positive regional nodes were significantly associated with OS and CSS in IIIA-N2 NSCLC (P < 0.05). However, PORT was not significantly associated with OS (univariate HR = 0.92, 95%CI 0.85-0.99, P = 0.02; multivariate HR = 1.01, 95%CI 0.93-1.08, P = 0.91) and CSS (univariate HR = 0.92, 95%CI 0.85-1.01, P = 0.06; multivariate HR = 1.103 95%CI 0.94-1.12, P = 0.56) in IIIA-N2 NSCLC. Meanwhile, after PSM, neither OS nor CSS did differ significantly between the non-PORT group and PORT group (OS HR = 1.08, 95%CI 0.98-1.19, P = 0.12; CSS HR = 1.10, 95%CI 0.99-1.23, P = 0.07).

CONCLUSION

PORT did not contribute to a survival benefit in patients with surgically treated stage IIIA-N2 NSCLC.

Role of Diffusion-Weighted Magnetic Resonance Imaging for Characterization of Mediastinal Lymphadenopathy

BACKGROUND

To assess the diagnostic performance of diffusion-weighted (DW) magnetic resonance imaging (MRI) in the characterization of mediastinal lymph nodes and compare them with morphological parameters.

METHODS

A total of 43 untreated patients with mediastinal lymphadenopathy underwent DW and T2 weighted MRI followed by pathological examination in the period from January 2015 to June 2016. The presence of diffusion restriction, apparent diffusion coefficient (ADC) value, short axis dimensions (SAD), and T2 heterogeneous signal intensity of the lymph nodes were evaluated using receiver operating characteristic curve (ROC) and forward step-wise multivariate logistic regression analysis.

RESULTS

The ADC of malignant lymphadenopathy was significantly lower (0.873 ± 0.109 × 10^-3 mm²/s) than that of benign lymphadenopathy (1.663 ± 0.311 × 10^-3 mm²/s) (p = 0.001). When an ADC of 1.0955 × 10^-3 mm²/s was used as a threshold value for differentiating malignant from benign nodes, the best results were obtained with a sensitivity of 94%, a specificity of 96%, and an area under the curve (AUC) of 0.996. A model combining the other three MRI criteria showed less sensitivity (88.9%) and specificity (92%) compared to the ADC-only model.

CONCLUSION

The ADC was the strongest independent predictor of malignancy. The addition of other parameters failed to show any increase in sensitivity and specificity.

Lymph node sampling-what are the numbers?

Lung cancer is a deadly disease. Lymph node staging is the most important prognostic factor, and lymphatic drainage of the lung is complex. Major advances have been made in this field over the last several decades, but there is much left to understand and improve upon. Herein, we review the history of the lymphatic system and the creation of lymph node maps, the evolution of tumor, node, and metastasis lung cancer classification, the importance of lung cancer staging, techniques for lymph node dissection, and our recommendations regarding a minimum number of nodes to sample during pulmonary resection.

[Review for N2 Sub-staging in Non-small Cell Lung Cancer]

Patients with N2 non-small cell lung cancer (NSCLC) were heterogeneous groups and required further stratification. The International Society for the Study of Lung Cancer (IASLC) divided N2 into three sub-stages: N2 at a single station without N1 involvement (N2a1), N2 at a single station with N1 involvement (N2a2), and N2 at multiple stations (N2b). These new descriptors significantly distinguished the overall survival (OS), disease-free survival (DFS), and recurrence pattern of patients with different N2 sub-stages. The OS and DFS of N2a1 were not sufficiently distinguished from N1 at multiple stations (N1b). The OS and DFS of N2a2 were intermediate between those of N2a1 and N2b. Current evidence did not support the further subdivision of the N2b. The main recurrence pattern of N2a1, N2a2 and N2b were distant metastasis, and the risks of distant metastasis increased successively. N2a1 patients were at low risk of locoregional recurrence, which could not be reduced by postoperative radiotherapy (PORT). N2a2 and N2b patients had a similar higher risk of locoregional recurrence, which could be reduced to a similar level of N2a1 patients by PORT.
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Multidisciplinary Postoperative Validation of 18F-FDG PET/CT Scan in Nodal Staging of Resected Non-Small Cell Lung Cancer

BACKGROUND

The aim of this study was to examine the validity of PET/CT scans in the preoperative identification of lymph node metastases (LNM) and compare them with postoperative outcomes.

METHODS

In this retrospective study, we included 87 patients with a solitary lung nodule or biopsy-proven non-small cell lung cancer treated in our institution from 2009 to 2015. Patients were divided into two groups and four subgroups, depending on pre- and postoperative findings.

RESULTS

According to our analysis, PET/CT scan has a sensitivity of 50%, a specificity of 88.89%, a positive predictive value of 63.16%, and a negative predictive value of 82.35%. Among the patients, 13.8% were downstaged in PET-CT, while 8% were upstaged. In 78.2% of cases, the PET/CT evaluation was consistent with the histology. Metastases without extracapsular invasion were seldom recognized on PET/CT.

CONCLUSIONS

This analysis showed the significance of extracapsular tumor invasion, which causes an inflammatory reaction, on LNM, which is probably responsible for preoperative false-positive findings. In conclusion, PET/CT scans are very effective in identifying patients without tumors. Furthermore, it is highly probable that patients with negative findings are free of disease.

Pharmacological, Nutritional, and Rehabilitative Interventions to Improve the Complex Management of Osteoporosis in Patients with Chronic Obstructive Pulmonary Disease: A Narrative Review

Osteoporosis is a highly prevalent condition affecting a growing number of patients affected by chronic obstructive pulmonary disease (COPD), with crucial implications for risk of fragility fractures, hospitalization, and mortality. Several risk factors have been identified to have a role in osteoporosis development in COPD patients, including corticosteroid therapy, systemic inflammation, smoke, physical activity levels, malnutrition, and sarcopenia. In this scenario, a personalized multitarget intervention focusing on the pathological mechanisms underpinning osteoporosis is mandatory to improve bone health in these frail patients. Specifically, physical exercise, nutritional approach, dietary supplements, and smoke cessation are the cornerstone of the lifestyle approach to osteoporosis in COPD patients, improving not only bone health but also physical performance and balance. On the other hand, pharmacological treatment should be considered for both the prevention and treatment of osteoporosis in patients at higher risk of fragility fractures. Despite these considerations, several barriers still affect the integration of a personalized approach to managing osteoporosis in COPD patients. However, digital innovation solutions and telemedicine might have a role in optimizing sustainable networking between hospital assistance and community settings to improve bone health and reduce sanitary costs of the long-term management of COPD patients with osteoporosis.

A Comprehensive Comparison of Different Nodal Subclassification Methods in Surgically Resected Non-Small-Cell Lung Cancer Patients

INTRODUCTION

The revision of the N descriptor in non-small-cell lung cancer has been widely discussed in the past few years. Many different subclassification methods based on number or location of lymph nodes have been proposed for better distinguishing different N patients. This study aimed to systematically collect them and provide a comprehensive comparison among different subclassification methods in a large cohort.

METHOD

Pathological N1 or N2 non-small-cell lung cancer patients undergoing surgical resection between 2005 and 2016 in the Western China Lung Cancer Database were retrospectively reviewed. A literature review was conducted to collect previous subclassification methods. Kaplan-Meier and multivariable Cox analyses were used to examine the prognostic performance of subclassification methods. Decision curve analysis, Akaike's information criterion, and area under the receiver operating curve concordance were also performed to evaluate the standardized net benefit of the subclassification methods.

RESULTS

A total of 1625 patients were identified in our cohort. Eight subclassification methods were collected from previous articles and further grouped into subclassification based on number categories (node number or station number), location categories (lymph node zone or chain) or combination of number and location categories. Subclassification based on combination of lymph node location and number tended to have better discrimination ability in multivariable Cox analysis. No significant superiority among the different subclassification methods was observed in the three statistical models.

CONCLUSION

Subclassification based on the combination of location and number could be used to provide a more accurate prognostic stratification in surgically resected NSCLC and is worth further validation.

The Impact of Skip vs. Non-Skip N2 Lymph Node Metastasis on the Prognosis of Non-Small-Cell Lung Cancer: A Systematic Review and Meta-Analysis

Objective: The skip N2 metastases were frequent in non-small-cell lung cancer (NSCLC) and the better prognosis of NSCLC with a skip over non-skip N2 lymph node metastases is controversial. The primary aim of this study is to investigate the prognosis effect of skip N2 lymph node metastases on the survival of NSCLC.

Setting: A literature search was conducted in PubMed, EMBASE, and Cochrane Library with the term of “N2” or “mediastinal lymph node” or “mediastinal nodal metastases”, and “lung cancer” and “skip” or “skipping” in the title/abstract field. The primary outcomes of interests are 3- and 5-year survival in NSCLC.

Participants: Patients who underwent complete resection by lobectomy, bilobectomy, or pneumonectomy with systemic ipsilateral lymphadenectomy and were staged as pathologically N2 were included.

Primary and Secondary Outcome Measures: The 3- and 5-year survival of NSCLC was analyzed. The impact of publication year, number of patients, baseline mean age, gender, histology, adjuvant therapy, number of skip N2 stations, and survival analysis methods on the primary outcome were also analyzed.

Results: A total of 21 of 409 studies with 6,806 patients met the inclusion criteria and were finally included for the analysis. The skip N2 lymph node metastases NSCLC had a significantly better overall survival (OS) than the non-skip N2 NSCLC [hazard ratio (HR), 0.71; 95% CI, 0.62–0.82; P < 0.001; I² = 40.4%]. The skip N2 lymph node metastases NSCLC had significantly higher 3- and 5-year survival rates than the non-skip N2 lymph node metastases NSCLC (OR, 0.75; 95% CI, 0.66–0.84; P < 0.001; I² = 60%; and OR, 0.78; 95% CI, 0.71–0.86; P < 0.001; I² = 67.1%, respectively).

Conclusion: This meta-analysis suggests that the prognosis of skip N2 lymph node metastases NSCLC is better than that of a non-skip N2 lymph node.

A Prediction Model to Optimize Invasive Mediastinal Staging Procedures for Non-Small Cell Lung Cancer in Patients With a Radiologically Normal Mediastinum: The Quebec Prediction Model

BACKGROUND

Current guideline-recommended criteria for invasive mediastinal staging in patients with a radiologically normal mediastinum fail to identify a significant proportion of patients with occult mediastinal disease (OMD), despite it leading to a large number of invasive staging procedures.

RESEARCH QUESTION

Which variables available before surgery predict the probability of OMD in patients with a radiologically normal mediastinum?

STUDY DESIGN AND METHODS

We identified all cTxN0/N1M0 non-small cell lung cancer tumors staged by CT imaging and PET with CT imaging in our institution between 2014 and 2018 who underwent gold standard surgical lymph node dissection or were demonstrated to have OMD before surgery by invasive mediastinal staging techniques and divided them into a derivation and an independent validation cohort to create the Quebec Prediction Model (QPM), which allows calculation of the probability of OMD.

RESULTS

Eight hundred three patients were identified (development set, n = 502; validation set, n = 301) with a prevalence of OMD of 9.1%. The developed prediction model included largest mediastinal lymph node size (P < .001), tumor centrality (P = .23), presence of cN1 disease (P = .29), and lesion standardized uptake value (P = .09). Using a calculated probability of more than 10% as a threshold to identify OMD, this model had a sensitivity, specificity, positive predictive value, and negative predictive value in the derivation cohort of 73.9% (95% CI, 58.9%-85.7%), 81.1% (95% CI, 77.2%-84.6%), 28.3% (95% CI, 23.4%-33.8%), and 96.8% (95% CI, 95.0%-98.1%), respectively. It performed similarly in the validation cohort (P = .77, Hosmer-Lemeshow test; P = .5163, Pearson χ² and unweighted sum-of-squares statistics; and P = .0750, Stukel score test) and outperformed current guideline-recommended criteria in identifying patients with OMD (area under the receiver operating characteristic curve [AUC] for American College of Chest Physicians guidelines criteria, 0.65 [95% CI, 0.59-0.71]; AUC for European Society of Thoracic Surgeons guidelines criteria, 0.60 [95% CI, 0.54-0.67]; and AUC for the QPM, 0.85 [95% CI, 0.80-0.90]).

INTERPRETATION

The QPM allows the clinician to integrate available information from CT and PET imaging to minimize invasive staging procedures that will not modify management, while also minimizing the risk of unforeseen mediastinal disease found at surgery.

The influence of the number of lymph nodes removed on the accuracy of a newly proposed N descriptor classification in patients with surgically-treated lung cancer

INTRODUCTION

The International Association for the Study of Lung Cancer has proposed a new classification of N descriptor based on the number of metastatic lymph nodes (LNs) stations, including skip metastasis. The aim of the study was to determine the effect of removed LNs on the adequacy of this new classification.

MATERIALS AND METHODS

The material was collected retrospectively based on the database of the Polish Lung Cancer Group, including information on 8016 patients with non-small cell lung cancer operated in 23 thoracic surgery centers in Poland. The material covered the period from January 2005 to September 2015. We divided patients into two groups: ≤6LNs and >6LNs removed.

RESULTS

In the whole group, an average of 13.4 nodes and 4.54 nodal stations were removed. 5-year survivals in the >6LNs group vs ≤ 6LNs group were: 62.3% and 55.1% (N0), 44.5% and 35.9% (N1a), 34.1% and 31,7% (N1b), 37.3% and 26.3% (N2a1), 32.4% and 26.7% (N2a2), 29.4% and 29.2% (N2b1), and 22.0% and 23.0% (N2b2), respectively. Comparing these groups, we detected significant differences at N0 (p < 0.001) and N2a1 (p = 0.022). In the ≤6LNs group, the survival curves for N2a1, N2a2, N2b1, and N2b2 overlapped (p > 0.05). In the >6LNs group, the survival curves were significantly different between grades, with survival for N2a1 better than N1b (p = 0.232).

CONCLUSION

The proposed classification N descriptor is potentially better at differentiating patients into different stages. The accuracy of the classification depends on the number of lymph nodes removed. Therefore, the extent of lymphadenectomy has a significant impact on the staging of surgically-treated lung cancer.

Alternative methods of lymph node staging in lung cancer: a narrative review

The nodal status indicator in non-small cell lung cancer is one of the most crucial prognostic factors available. However, there are still many arguments among scientists regarding whether the currently used nodal status descriptor should be changed in the forthcoming editions of the Tumor Node Metastasis classification or whether it is precise enough and should be maintained as is. We reviewed studies concerning nodal factor classifications to evaluate their accuracy in non-small cell lung cancer patients and to address the previously mentioned challenge. We reviewed the PubMed database regarding the following classifications: ongoing 8^th edition of the Tumor Node Metastasis classification, number of positive lymph nodes, number of negative lymph nodes, number of dissected lymph nodes, lymph node ratio, nodal chains, log odds of positive lymph nodes, zone-based classification and one that is based on the number of lymph node stations involved. Moreover, we analysed data regarding various combinations of these classifications. Our analysis showed that the present nodal staging may not accurately categorize every lung cancer patient. The number of positive lymph nodes and lymph node ratio or the log odds of positive lymph nodes (as the mathematical modification of lymph node ratio) are more legitimate, as they possess very robust data and should be considered initially as additional factors that can be incorporated in ongoing nodal staging systems. Forthcoming non-small cell lung cancer staging systems could benefit from the addition of quantitative-based parameters. Additionally, the minimal extent of lymphadenectomy should be established as staging benefits from it. International, prospective validation studies need to be performed to optimize the cut-off values and prognostic groups and to confirm the superiority of the newly suggested descriptors in non-small cell lung cancer nodal staging.

Postoperative radiotherapy option based on mediastinal lymph node reclassification for patients with pN2 non-small-cell lung cancer

Background

In this research, we used the mediastinal lymph node reclassification proposed by the International Association for the Study of Lung Cancer (iaslc) to screen for patients with pathologic N2 (pN2) non-small-cell lung cancer (nsclc) who might benefit from postoperative radiotherapy (port).

Methods

The study enrolled 440 patients with pN2 nsclc who received complete surgical resection and allocated them to one of three groups: N2a1 (single-station skip mediastinal lymph node metastasis), N2a2 (single-station non-skip mediastinal lymph node metastasis), and N2b (multi-station mediastinal lymph node metastasis). Rates of local recurrence at first recurrence in patients receiving and not receiving port were compared using the chi-square test. Overall (os) and disease-free survival (dfs) were then compared using Kaplan-Meier survival analysis with log-rank test. In addition, the factors potentially influencing os and dfs were analyzed using univariate and multivariate Cox regression.

Results

The rate of local recurrence for the N2a2 and N2b groups was significantly lower in patients receiving port (p = 0.044 and p = 0.043 respectively). The log-rank test revealed that, for the N2a1 group, differences in os and dfs were not statistically significant between the patients who did and did not receive port (p = 0.304 and p = 0.197 respectively). For the N2a2 group, os and dfs were markedly superior in patients who received port compared with those who did not (p = 0.001 and p = 0.014 respectively). For the N2b group, os was evidently better in patients who received port compared with those who did not (p = 0.025), but no statistically significant difference in dfs was observed (p = 0.134). Multivariate regression analysis revealed that, in the N2a1 group, port was significantly associated with poor os [hazard ratio (hr): 2.618; 95% confidence interval (ci): 1.185 to 5.785; p = 0.017]; in the N2a2 group, port was associated with improved os (hr: 0.481; 95% ci: 0.314 to 0.736; p = 0.001) and dfs (hr: 0.685; 95% ci: 0.479 to 0.980; p = 0.039).

Conclusions

For patients with pN2 nsclc who receive complete resection, port might be beneficial only for patients with single-station non-skip metastasis (N2a2). Patients with single-station skip metastasis (N2a1) and multi-station metastasis (N2b) might not currently benefit from port.

Risk analyses of N2 lymph-node metastases in patients with T1 non-small cell lung cancer: a multi-center real-world observational study in China

PURPOSE

N2 lymph-node metastases occur in approximately 6-17% of the patients with T1-2 non-small cell lung cancer (NSCLC). However, the clinical characteristics of N2 patients are not fully understood.

METHODS

This retrospective, multi-center analysis included T1 NSCLC patients receiving surgical resection during a period from Jan 2nd, 2014 to Dec 27th, 2017. The diagnosis was pathologically verified in all cases. Univariate and multivariate logistic regression analyses were conducted to analyze the factors that are associated with pN2 lymph-node metastases.

RESULTS

A total of 10,885 patients (48.4% men; 84.7% adenocarcinoma) were included in the analysis. The mean age was 59.0 ± 9.9 years. The mean tumor size was 1.8 ± 0.8 cm. Of the patients, 3260 (29.9%) were smokers or ex-smokers. Lymph-node metastases were verified in 1808 (16.6%) patients, and 1167 (10.7%) patients had N2 lymph-node metastases. The multivariate analyses indicated that larger tumor size, lower differentiation, CEA level ≥ 5 ng/mL, vascular invasion (+), and pleural involvement (+) were associated with higher percentages of N2 lymph-node metastases (p < 0.001 for all).

CONCLUSIONS

This study demonstrated the significant association between N2 lymph-node metastases and tumor size and differentiation, CEA levels, and status of vascular invasion and pleural involvement.