Predictors for hilar/intrapulmonary lymph node metastasis in discrete type of clinical N1 non-small cell lung cancer

A Shift in Paradigm: Selective Lymph Node Dissection for Minimizing Oversurgery in Early Stage Lung Cancer

Systematic lymph node dissection has been widely accepted and turned into a standard procedure for lung cancer surgery. In recent years, the concept of "minimal invasive surgery (MIS)" has greatly changed the surgical paradigm of lung cancer. Previous studies revealed that excessive dissection of lymph nodes without metastases had uncertain clinical benefit. Meanwhile, it leads to the elevated risk of postoperative complications including chylothorax and laryngeal nerve injury. In addition, dissection of nonmetastatic lymph nodes may disturb systematic immunity, resulting in the secondary effect on primary tumor or latent metastases. The past decades have witnessed the innovative strategies such as lobe-specific lymph node dissection and selective lymph node dissection. On the basis of evolution of lymph node dissection strategy, we discuss the negative effects of excessive nonmetastatic lymph node dissection and summarize the recent advances in the optimized dissection strategies, hoping to provide unique perspectives on the future directions.

Perioperative and Oncological Outcomes of Robotic-Assisted, Video-Assisted Thoracoscopic and Open Lobectomy for Patients with N1-Metastatic Non-Small Cell Lung Cancer: A Propensity Score-Matched Study

(1) Background: Despite the fact that robotic-assisted thoracoscopic lobectomy (RATL) has been prevalently applied for early stage non-small cell lung cancer (NSCLC), its superiorities are still to be fully revealed for patients with metastatic N1 lymph nodes (LNs). We aim to evaluate the advantages of RATL for N1 NSCLC. (2) Methods: This retrospective study identified consecutive pathological N1 NSCLC patients undergoing RATL, video-assisted thoracoscopic lobectomy (VATL), or open lobectomy (OL) in Shanghai Chest Hospital between 2014 and 2020. Further, perioperative and oncological outcomes were investigated. (3) Results: A total of 855 cases (70 RATL, 435 VATL, and 350 OL) were included. Propensity score matching resulted in 70, 140, and 140 cases in the RATL, VATL, and OL groups, respectively. RATL led to (1) the shortest surgical time (p = 0.005) and lowest intraoperative blood loss (p < 0.001); (2) the shortest ICU (p < 0.001) and postsurgical hospital (p < 0.001) stays as well as chest tube duration (p < 0.001); and (3) the lowest morbidities of postsurgical complications (p = 0.016). Moreover, RATL dissected more N1 (p = 0.027), more N1 + N2 (p = 0.027) LNs, and led to a higher upstaging incidence rate (p < 0.050) than VATL. Finally, RATL achieved a comparable 5-year disease-free and overall survival in relation to VATL and OL. (4) Conclusions: RATL led to the most optimal perioperative outcomes among the three surgical approaches and showed superiority in assessing N1 and total LNs over VATL, though it did achieve comparable oncological outcomes in relation to VATL and OL for N1 NSCLC patients.

Construction and Evaluation of a Preoperative Prediction Model for Lymph Node Metastasis of cIA Lung Adenocarcinoma Using Random Forest

Background

Lymph node metastasis (LNM) is the main route of metastasis in lung adenocarcinoma (LA), and preoperative prediction of LNM in early LA is key for accurate medical treatment. We aimed to establish a preoperative prediction model of LNM of early LA through clinical data mining to reduce unnecessary lymph node dissection, reduce surgical injury, and shorten the operation time.

Methods

We retrospectively collected imaging data and clinical features of 1121 patients with early LA who underwent video-assisted thoracic surgery at the First Hospital of China Medical University from 2004 to 2021. Logistic regression analysis was used to select variables and establish the preoperative diagnosis model using random forest classifier (RFC). The prediction results from the test set were used to evaluate the prediction performance of the model.

Results

Combining the results of logistic analysis and practical clinical application experience, nine clinical features were included. In the random forest classifier model, when the number of nodes was three and the n-tree value is 500, we obtained the best prediction model (accuracy = 0.9769), with a positive prediction rate of 90% and a negative prediction rate of 98.69%.

Conclusion

We established a preoperative prediction model for LNM of early LA using a machine learning random forest method combined with clinical and imaging features. More excellent predictors may be obtained by refining imaging features.

The impacts of isolated N1 lymph nodes metastasis on prognosis in non-small cell lung cancer: A single-center experience

Background: This study aims to investigate long-term results related to N1 group metastases with respect to anatomical localization and many external parameters and to examine the effect of these parameters on prognosis in patients with in nonsmall cell lung cancer.

Methods: Between January 2006 and May 2019, a total of 52 patients (44 males, 8 females; mean age: 59.9±9.5 years; range, 42 to 80 years) who underwent lobectomy due to primary lung malignancy were retrospectively analyzed. The N1 lymph nodes were divided into three anatomical groups as hilar, peribronchial, and intraparenchymal. Demographic features, tumor features, follow-up characteristics, and survival and diseasefree survival parameters were analyzed for each group. The results were also examined in terms of number of metastasis, number of metastatic levels, rate of metastasis, and histopathological type.

Results: The five-year survival rate was 66.4% in the peribronchial group and 50% in the hilar group. The five-year disease-free survival rate was 45.7% in the peribronchial group and 37.5% in the hilar group. There was no statistically significant difference between the groups in terms of survival and disease-free survival for anatomical localization, number of metastasis, number of metastatic levels, rate of metastasis, and histopathological type (p>0.05 for all).

Conclusion: The structure that would be formed by examining N1 in terms of parameters such as subtitle levels, number of metastasis, number of metastatic stations, rate of metastasis or combinations of these would have a more impact on the decisions in the follow-up and treatment process in this patient population.

Enlarged Mediastinal Lymph Nodes in Computed Tomography are a Valuable Prognostic Factor in Non-Small Cell Lung Cancer Patients with Pathologically Negative Lymph Nodes

Background

Most non-small cell lung cancer patients with enlarged mediastinal lymph nodes (LN) in preoperative computer tomography (CT) images are diagnosed with N0 in the pathological examination after surgery. However, these patients seem to have worse survival than those without enlarged mediastinal LN in our clinical practice. This study aimed to investigate whether the size of mediastinal LN is correlated with the prognosis in pathological N0 patients, which could help us to predict the prognoses further.

Methods

The retrospective cohort study involved 758 N0 patients with a thin layer CT scan. We have measured the size of mediastinal LN, including long diameter, short diameter, and volume on CT image, and classified patients by X-tile. Next, we explored the risk factors of enlarged LN by univariate and multivariate logistic analysis. Then, we have compared the 5-year cancer-specific survival by Kaplan-Meier and log-rank method. Multivariate Cox analysis was utilized to further survival analysis. Finally, we have constructed the prediction model by nomogram.

Results

A total of 150 N0 patients (19.8%) had mediastinal LN enlargement in our study. After multivariate logistic analysis, we found the LN enlargement was significantly correlated with age (p=0.001), pathology (p < 0.001) and tumor recurrence (p < 0.001). The patients with LN enlargement had a worse 5-year cancer-specific survival (75.3% vs 92.8%, p < 0.001) after Kaplan-Meier analysis. Patients with a larger volume had increased risk of tumor-associated death when compared with the normal group (p < 0.001) by multivariate Cox analyses.

Conclusion

N0 patients with larger mediastinal LN had a worse 5-year cancer-specific survival and a higher risk of recurrence. The volume of LN was the most valuable prognostic factor in N0 patients.

Clinicopathologic Significance of False-Positive Lymph Node Status on FDG-PET in Lung Cancer

INTRODUCTION

2-[¹⁸F] Fluoro-d-deoxyglucose (FDG) positron emission tomography (PET) is a relevant diagnostic procedure for staging lung cancer. However, accurate evaluation of lymph node metastases by PET is controversial because of false-positive FDG uptake.

PATIENTS AND METHODS

A total of 245 patients with lung cancer were retrospectively analyzed. Standardized maximum uptake values (SUV_max) of the primary tumor and lymph nodes were compared to pathologic lymph node metastases to correlate PET findings with clinicopathologic variables and patient outcomes.

RESULTS

The SUV_max values of metastatic lymph nodes were significantly higher than those of lymph nodes without metastases (P = .0036). When SUV_max ≥ 4 was defined as PET positive for metastasis, the sensitivity, specificity, and accuracy were 48.1%, 79.8%, and 73.1%, respectively. Multivariate logistic regression analysis showed that age > 75 years, bilateral hilar FDG uptake, and no lymph node swelling were significant factors related to false-positive lymph node metastases. Smoking status, FDG uptake in the primary tumor, and concurrent lung diseases were not significant factors.

CONCLUSION

Metastatic lymph nodes show higher FDG uptake than false-positive lymph nodes, and older patient age, bilateral hilar FDG uptake, and no swollen nodes are associated with no metastases. Patients with lymph node metastases have worse survival than those with false-positive FDG-PET findings. However, abnormal FDG uptake in the lymph node is an important prognostic factor.

Prognostic factor and treatment strategy for clinical N1 non-small cell lung cancer

OBJECTIVES

The aim of this study is to evaluate the surgical results of clinical N1 disease and to clarify the high-risk clinical N1 subgroup.

METHODS

Between 1990 and 2012, 137 patients who were clinically diagnosed as having N1 disease were enrolled. Their medical records were reviewed to assess clinical characteristics, radiologic findings, pathologic results, postoperative outcomes, recurrence patterns, and survival. Logistic regression analysis was used to identify independent predictive factors for pathologic N2 upstaging. To determine which factors were significantly associated with survival, a multivariate analysis using a Cox proportional hazards model was performed.

RESULTS

More cases were pathological N2 in adenocarcinoma than squamous cell carcinoma (p = 0.039). The overall survival rates at 5 years were 54.9%, 36.7% in group upper lobe, middle and lower lobe, respectively (p = 0.013). Logistic regression analyses revealed that #10 positive (p = 0.002, HR 4.625) and adenocarcinoma (p = 0.029, HR 1.544) were significant predictor of pathologic N2 disease. Multivariate analyses revealed that pathologic N2 (p = 0.007, HR 4.186), middle and lower lobe (p = 0.009, HR 2.045) and presence of #10 (p = 0.024, HR 1.871) were independent prognostic factors. Patients with upper lobe and absence of #10 showed a significantly higher 5-year survival rate than patients with middle and lower lobe and presence of #10 (62.1 vs 25.9%: p < 0.0001).

CONCLUSIONS

Among patients with cN1, pathological N2 disease, tumor in middle and lower lobe and clinical #10 lymph node positive were high-risk subgroup. Further analyses using larger numbers of patients with N1 disease from multiple centers are necessary.

Adjuvant chemotherapy may improve outcome of patients with non-small-cell lung cancer with metastasis of intrapulmonary lymph nodes after systematic dissection of N1 nodes

Objective

Survival benefit of adjuvant chemotherapy (AC) of patients with intrapulmonary lymph node (IPLN) metastasis (level 12−14) needs investigation. We evaluated the impact of AC on patients whose metastatic nodes were limited to intrapulmonary levels after systematic dissection of N1 nodes.

Methods

First, 155 consective cases of lung cancer confirmed as pathologic N1 were collected and evaluated. Patients received systematic dissection of N2 and N1 nodes. For patients with IPLN metastasis, survival outcomes were compared between those receiving AC and those not receiving AC.

Results

In this group, 112 cases (72.3%) had IPLN metastasis and 55 cases (35.5%) had N1 involvement limited to level 13−14 without further disease spread to higher levels. Patients with IPLN involvement had a better prognosis than that of patients with hilar-interlobar involvement. For the intrapulmonary N1 group (level 12−14-positive, level 10−11-negative or unknown, n=112), no survival benefit was found between the AC group and non-AC group [5-year overall survival (OS): 54.6±1.6vs. 50.4±2.4 months, P=0.177]. However, 76 of 112 cases for whom harvesting of level-10 and level-11 nodes was done did not show cancer involvement in pathology reports (level 12−14-positive, level 10−11 both negative), oncologic outcome was better for patients receiving AC than those not receiving AC in this subgroup (5-year OS: 57.3±1.5vs. 47.1±3.2 months, P=0.002).

Conclusions

Oncologic outcome may be improved by AC for patients with involvement of N1 nodes limited to intrapulmonary levels after complete examination of N1 nodes.