Selective lymph node dissection in early-stage non-small cell lung cancer

Preservation vs. dissection of inferior pulmonary ligament for thoracoscopic upper lobectomy: a prospective randomized controlled trial

OBJECTIVES

The proper procedure for inferior pulmonary ligament (IPL) during upper lobectomy remains a topic of debate. To address this matter, we carried out a trial comparing the clinical outcomes of IPL preservation versus IPL dissection during thoracoscopic upper lobectomy (TUL).

METHODS

Patients undergoing thoracoscopic left/right upper lobectomy (TLUL/TRUL) were assigned to either the dissection group (Group D) or the preservation group (Group P). Our primary objective was to quantify and compare the alterations in postoperative residual bronchial angle and lung volume changes between the two groups. Our secondary objective encompassed the assessment of various other intraoperative and postoperative outcomes.

RESULTS

Following adherence to the inclusion and exclusion criteria, we enrolled 100 patients (41 left and 59 right) in Group P and 108 patients (41 left and 67 right) in Group D for the study. Our findings revealed that in TLUL, Group P was able to reduce the degree of postoperative residual bronchial angle change (P < 0.05). Conversely, the situation was distinct for TRUL. We found no notable disparity between the two groups (P > 0.05) with regard to alterations in lung volume or the occurrence of postoperative complications-except for the duration of postoperative hospital stay (P < 0.05).

CONCLUSIONS

Our study suggests IPL preservation especially for TLUL when compared to TRUL, which have important implications for the clinical management of patients undergoing upper lobectomy.

A Systematic Review of Short-Term Outcomes of Minimally Invasive Thoracoscopic Surgery for Lung Cancer after Neoadjuvant Systemic Therapy

BACKGROUND

Minimally invasive surgeries for non-small cell lung cancers (NSCLCs) such as video-assisted thoracoscopic surgeries (VATSs) and robotic-assisted thoracoscopic surgeries (RATSs) have become standard of care for patients needing surgical resection in early stages. The role for neoadjuvant systemic therapy has increased with patients receiving neoadjuvant systemic chemotherapy and immunotherapy. However, there has been some equipoise over the intraoperative and overall outcomes for these patients. Here, we review the current data regarding outcomes of patients undergoing minimally invasive thoracic surgical resection after systemic chemotherapy, immunotherapy, or both.

METHODS

A systematic literature review of randomized controlled trials and observational studies presenting data on patients with NSCLC that underwent neoadjuvant systemic therapy followed by minimally invasive surgery was performed assessing complications, conversion rates, and lymph node yield.

RESULTS

Our search strategy and review of references resulted in 239 publications to screen with 88 full texts assessed and 21 studies included in our final review. VATS had a statistically significant higher lymph node yield in five studies. The reported conversion rates ranged from 0 to 54%. Dense adhesions, bleeding, and difficult anatomy were the most common reported reasons for conversion to open surgeries. The most common complications between both groups were prolonged air leak, arrythmia, and pneumonia. VATS was found to have significantly fewer complications in three papers.

CONCLUSIONS

The current literature supports VATS as safe and feasible for patients with NSCLC after neoadjuvant systemic treatment. Surgeons should remain prepared to convert to open surgeries in those patients with dense adhesions and bleeding risk.

LobE-Specific lymph node diSsectiON for clinical early-stage non-small cell lung cancer: protocol for a randomised controlled trial (the LESSON trial)

INTRODUCTION

Lung cancer was the most common malignancy and the leading cause of cancer-related death in China or worldwide, and surgery is still the preferred treatment for early-stage non-small cell lung cancer (NSCLC). The pattern of lymph node metastasis was found potentially lobe specific, and thus, lobe-specific lymph node dissection (L-SLND) was proposed to be an alternative to systematic lymph node dissection (SLND) for the treatment of early-stage NSCLC.

METHODS AND ANALYSIS

The LobE-Specific lymph node diSsectiON trial is a single-institutional, randomised, double-blind and parallel controlled trial to investigate the feasibility of L-SLND in clinically diagnosed stage IA1-2 NSCLC with ground-glass opacity components (≥50%). The intraoperative frozen section examination of surgical tissues confirms the histological type of NSCLC. We hypothesise that L-SLND (experimental group) is not inferior to SLND (control group) and intend to include 672 participants for the experimental group and 672 participants for the control group with a follow-up duration of 60 months. The primary outcomes are 5-year disease-free survival and 5-year overall survival. The secondary outcomes are metastatic lymph node ratio, postoperative complication incidence and mortality, duration of operation, duration of anaesthesia (min), the volume of bleeding (mL) and drainage volume. The intention-to-treat analysis would be performed in the trial.

ETHICS AND DISSEMINATION

This trial was approved by the ethics committee on biomedical research, West China Hospital of Sichuan University (2021-332). Informed consent would be obtained from all participants, and dissemination activities would include academic conference presentations and peer-reviewed publications.

TRIAL REGISTRATION NUMBER

This trial was registered in the Chinese Clinical Trial Registry, ChiCTR2100048415.

Detection of lymph node metastasis in non-small cell lung cancer using the new system of one-step nucleic acid amplification assay

Introduction

The prognosis of non-small cell lung cancer greatly depends on the presence of lymph node metastasis, which limits the need for surgery and adjuvant therapy for advanced cancer. One-step nucleic acid amplification of cytokeratin19 (CK19) mRNA was used to detect lymph node metastasis. Automated Gene Amplification Detector RD-200 and the LYNOAMP CK19 gene amplification reagent as components of the new one-step nucleic acid amplification system, which has increased gene amplification efficiency by improving the reagent composition, have shorter preprocessing and measurement times than conventional systems. We aimed to compare the clinical performance of the new system with that of histopathology and the conventional system.

Materials and methods

199 lymph nodes from 58 non-small cell lung cancer patients who underwent lymph node dissection were examined intraoperatively using the new system, conventional system, and histopathology.

Results

Lymph node metastasis was diagnosed in 32, 42, and 44 patients using histopathological analysis, the new system, and the conventional system, respectively. Compared with histopathological analysis, the concordance rate, sensitivity, specificity, positive predictive value, and negative predictive value of the new system were 92.0%, 90.6%, 92.2%, 69.0%, and 98.1%, respectively, and compared with the conventional system, the values were 95.0%, 86.4%, 97.4%, 90.5%, and 96.2%, respectively.

Conclusion

The clinical performance of the new one-step nucleic acid amplification system in detecting lymph node metastasis of lung cancer is comparable to that of histopathology and the conventional system; its performance was sufficient for determining the appropriate clinical treatment. The new rapid system can be effectively utilized during lung cancer treatment intraoperatively and postoperatively.

Imbalanced Data Correction Based PET/CT Radiomics Model for Predicting Lymph Node Metastasis in Clinical Stage T1 Lung Adenocarcinoma

OBJECTIVES

To develop and validate the imbalanced data correction based PET/CT radiomics model for predicting lymph node metastasis (LNM) in clinical stage T1 lung adenocarcinoma (LUAD).

METHODS

A total of 183 patients (148/35 non-metastasis/LNM) with pathologically confirmed LUAD were retrospectively included. The cohorts were divided into training vs. validation cohort in a ratio of 7:3. A total of 487 radiomics features were extracted from PET and CT components separately for radiomics model construction. Four clinical features and seven PET/CT radiological features were extracted for traditional model construction. To balance the distribution of majority (non-metastasis) class and minority (LNM) class, the imbalance-adjustment strategies using ten data re-sampling methods were adopted. Three multivariate models (denoted as Traditional, Radiomics, and Combined) were constructed using multivariable logistic regression analysis, where the combined model incorporated all of the significant clinical, radiological, and radiomics features. One hundred times repeated Monte Carlo cross-validation was used to assess the application order of feature selection and imbalance-adjustment strategies in the machine learning pipeline. Prediction performance of each model was evaluated using the area under the receiver operating characteristic curve (AUC) and Geometric mean score (G-mean).

RESULTS

A total of 2 clinical parameters, 2 radiological features, 3 PET, and 5 CT radiomics features were significantly associated with LNM. The combined model with Edited Nearest Neighbors (ENN) re-sampling methods showed strong prediction performance than traditional model or radiomics model with the AUC of 0.94 (95%CI = 0.86-0.97) vs. 0.89 (95%CI = 0.79-0.93), 0.92 (95%CI = 0.85-0.97), and G-mean of 0.88 vs. 0.82, 0.80 in the training cohort, and the AUC of 0.75 (95%CI = 0.57-0.91) vs. 0.68 (95%CI = 0.36-0.83), 0.71 (95%CI = 0.48-0.83) and G-mean of 0.76 vs. 0.64, 0.51 in the validation cohort. The combination of performing feature selection before data re-sampling obtains a better result than the reverse combination (AUC 0.76 ± 0.06 vs. 0.70 ± 0.07, p<0.001).

CONCLUSIONS

The combined model (consisting of age, histological type, C/T ratio, MATV, and radiomics signature) integrated with ENN re-sampling methods had strong lymph node metastasis prediction performance for imbalance cohorts in clinical stage T1 LUAD. Radiomics signatures extracted from PET/CT images could provide complementary prediction information compared with traditional model.

Nomogram based on prognostic nutrition index and Chest CT imaging signs predicts lymph node metastasis in NSCLC patients

OBJECTIVE

To establish and validate a model capable of predicting lymph node metastasis (LNM) of non-small cell lung cancer (NSCLC) patients.

METHODS

Preoperative clinical and CT imaging data on patients with NSCLC undergoing surgery were retrospectively analyzed. A model was developed using a training cohort of 290 patients. The univariate analysis followed by dichotomous logistic regression was performed to estimate different risk factors of lymph node metastasis, and a nomogram was constructed. Using another testing cohort of 120 patients, the performance of the nomogram was validated using several evaluation methods and indices and evaluated including via the area under the curve (AUC), calibration curve, Hosmer-Lemeshow test and decision curve analysis (DCA).

RESULTS

CT-based imaging signs were important independent risk factors for lymph node metastasis in NSCLC patients. The possible risk factors also included four other independent risk factors through dichotomous logistic regression, i.e., age, SIRI, PNI and CEA, which were filtered and included in the nomogram. Nomogram yields AUC values of 0.828 [95% confidence interval (CI): 0.778-0.877] in the training cohort and 0.816 (95% CI: 0.737-0.895) in the validation cohort, respectively. The calibration curves showed high agreement in both the training and validation cohorts. At the threshold probability of 0-0.8, the nomogram increases the net outcomes compared to the treat-none and treat-all lines in the decision curve.

CONCLUSIONS

The nomogram based on the PNI and CT images signs holds promise as a novel and accurate tool for predicting the LNM in NSCLC patients and guiding intraoperative lymph node dissection.

Lung cancer staging, the established role of bronchoscopy

PURPOSE OF REVIEW

Lung cancer is the leading cause of cancer-related deaths worldwide. In the absence of distant metastases, accurate mediastinal nodal staging determines treatment approaches to achieve most favourable outcomes for patients. Mediastinal staging differentiates N0/N1 disease from N2/N3 in surgical candidates. Likewise, presence of nodal involvement in nonsurgical candidates who are being considered for stereotactic body radiation therapy is also critical. This review article seeks to discuss the current options available for mediastinal staging in nonsmall cell lung cancer (NSCLC), particularly the role of bronchoscopy.

RECENT FINDINGS

Although several techniques are available to stage the mediastinum, bronchoscopy with EBUS-TBNA with or without EUS-FNA appears to be superior in most clinical situations based on its ability to concomitantly diagnose and stage at once, safety, accessibility to the widest array of lymph node stations, cost and low risk of complications. However, training and experience are required to achieve consistent diagnostic accuracy with EBUS-TBNA.

SUMMARY

EBUS-TBNA with or without EUS-FNA is considered the modality of choice in the diagnosis and staging of NSCLC in both surgical and nonsurgical candidates.

Multi-energy level fusion for nodal metastasis classification of primary lung tumor on dual energy CT using deep learning

Lymph node metastasis also called nodal metastasis (Nmet), is a clinically primary task for physicians. The survival and recurrence of lung cancer are related to the Nmet staging from Tumor-Node-Metastasis (TNM) reports. Furthermore, preoperative Nmet prediction is still a challenge for the patient in managing the surgical plan and making treatment decisions. We proposed a multi-energy level fusion model with a principal feature enhancement (PFE) block incorporating radiologist and computer science knowledge for Nmet prediction. The proposed model is custom-designed by gemstone spectral imaging (GSI) with different energy levels on dual-energy computer tomography (CT) from a primary tumor of lung cancer. In the experiment, we take three different energy level fusion datasets: lower energy level fusion (40, 50, 60, 70 keV), higher energy level fusion (110, 120, 130, 140 keV), and average energy level fusion (40, 70, 100, 140 keV). The proposed model is trained by lower energy level fusion that is 93% accurate and the value of Kappa is 86%. When we used the lower energy level images to train the fusion model, there has been a significant difference to other energy level fusion models. Hence, we apply 5-fold cross-validation, which is used to validate the performance result of the multi-keV model with different fusion datasets of energy level images in the pathology report. The cross-validation result also demonstrates that the model with the lower energy level dataset is more robust and suitable in predicting the Nmet of the primary tumor. The lower energy level shows more information of tumor angiogenesis or heterogeneity provided the proposed fusion model with a PFE block and channel attention blocks to predict Nmet from primary tumors.

Selective Mediastinal Lymphadenectomy or Complete Mediastinal Lymphadenectomy for Clinical Stage I Non-Small Cell Lung Cancer: A Meta-Analysis

INTRODUCTION

Selective mediastinal lymphadenectomy (SML) and complete mediastinal lymphadenectomy (CML) are two main types of surgery conducted for the treatment of non-small cell lung cancer (NSCLC) plus lobectomy or segmentectomy. It is not known whether stage I NSCLC can benefit from CML. Using the meta-analytical method, our research aimed to find out the worth of SML and CML for the therapy of clinical stage I NSCLC.

METHODS

We searched PubMed, Ovid, MEDLINE, Cochrane Controlled Trial Register (CENTRAL), Embase, and Google Scholar for literature published up to June 2021 to evaluate the comparative research and to assess the post-operative complications, overall survival rate, disease-free survival rate, and local and distant recurrence. This meta-analysis was conducted by combining the results of the reported incidences of post-operative complications, local and distant recurrence, and short- and long-term mortality. The pooled odds ratios (OR) and the 95% confidence intervals were calculated by random or fixed effects models to compare the effectiveness between these two methods.

RESULTS

Five retrospective studies and one randomized controlled trial study were included in our research. The six studies included a total of 5713 patients, of whom 1480 were assigned to the SML group and 4233 were assigned to the CML group. No statistically significant differences were found in the 1- and 5-year overall survival rates or the 1-, 3-, and 5-year disease-free survival rates between the two groups. However, the 3-year overall survival favored the SML group (P < 0.05). There were also no statistically significant differences between the local and distant metastasis. Among the postoperative complications, pneumonia, atelectasis, and prolonged air leak were more common in the CML group (P < 0.05). There were no differences in the prevalence of dysrhythmia, chylothorax, acute respiratory distress syndrome, or recurrent laryngeal nerve injury between the two groups, which may be due to the limited sample size.

CONCLUSION

Considering the comparable survival rates, disease control, and fewer postoperative complications in the evaluated participants, SML is the preferred treatment with less invasiveness for clinical stage I NSCLC.

Lobe-specific lymph node dissection in stage IA non-small-cell lung cancer: a retrospective cohort study

OBJECTIVES

To investigate lymph node (LN) metastasis according to tumour location and assess the impact of lobe-specific LN dissection on survival in stage IA non-small-cell lung cancer (NSCLC).

METHODS

We retrospectively analysed the data of patients with clinical stage IA NSCLC treated with lobectomy and systematic LN dissection at Asan Medical Center (Seoul, Korea) between June 2005 and April 2017. Patients who received neoadjuvant therapy had multiple primary tumours or missed the follow-up during the first postoperative year were excluded. The patients were divided into five groups according to involved lung lobes: right upper lobe (RUL), right middle lobe (RML), right lower lobe (RLL), left upper lobe (LUL) and left lower lobe (LLL), which were further divided into subgroups according to LN station metastasis. Overall survival (OS) and the incidence of metastasis were calculated for each subgroup. Efficacy indices (EIs) were calculated to determine the correlation between each lung lobe and LN station, and the impact of the dissection of these stations on survival.

RESULTS

A total of 1202 patients were analysed. The 5-year OS in the RUL, RML, RLL, LUL and LLL groups was 74%, 88%, 78%, 80% and 75%, respectively. The incidence of single LN station metastasis was 11%, 10%, 10%, 16% and 14%, respectively. The lobe-specific LNs for RUL, RML, RLL, LUL and LLL were stations 2/3/4, 4/7, 2/4/7, 4/5/6 and 6/7/9, respectively. Moreover, the LN stations with high EIs for RUL, RML, RLL, LUL and LLL were 4, 7, 7, 5 and 7, respectively. In the RUL group, the incidence of metastasis to stations 2, 3 and 4 was 2.3%, 0.5% and 7.6%, and the EI was 0.8, 0.3 and 4.3, respectively. In RML, the incidence of metastasis to stations 4 and 7 was 4% and 6%, and the EI was 1.3 and 2.4, respectively. In RLL, the incidence of metastasis to stations 2, 4 and 7 was 4.4%, 5.6% and 8.3%, and the EI was 1.3, 1.4 and 3.3, respectively. In LUL, the incidence of metastasis to stations 4, 5 and 6 was 1.4%, 11.8% and 2.5%, and the EI was 0.4, 7.1 and 0.5, respectively. In LLL, the incidence of metastasis to stations 6, 7 and 9 was 1.1%, 5.7% and 1.7%, and the EI was 0.6, 2.3 and 0.5, respectively. Furthermore, the OS of patients with lobe-specific LN metastasis was statistically significantly different from that of the non-lobe-specific LN metastasis group with P-values of <0.001 for RUL, 0.002 for RML, 0.002 for RLL, 0.001 for LUL and 0.003 for LLL.

CONCLUSIONS

Our findings support the use of lobe-specific LN dissection in stage IA NSCLC. When LN stations with high EI were negative, LN metastasis in other stations was unlikely. The incidence of LN metastasis beyond lobe-specific LN stations was ∼1% in all subgroups. Dissection of non-lobe-specific LNs may not improve the OS; however, prospective randomized controlled trials are needed to modify the standard approach.

Integrative nomogram of intratumoral, peritumoral, and lymph node radiomic features for prediction of lymph node metastasis in cT1N0M0 lung adenocarcinomas

Radiomics studies to predict lymph node (LN) metastasis has only focused on either primary tumor or LN alone. However, combining radiomics features from multiple sources may reflect multiple characteristic of the lesion thereby increasing the discriminative performance of the radiomic model. Therefore, the present study intends to evaluate the efficiency of integrative nomogram, created by combining clinical parameters and radiomics features extracted from gross tumor volume (GTV), peritumoral volume (PTV) and LN, for the preoperative prediction of LN metastasis in clinical cT1N0M0 adenocarcinoma. A primary cohort of 163 patients (training cohort, 113; and internal validation cohort, 50) and an external validation cohort of 53 patients with clinical stage cT1N0M0 were retrospectively included. Features were extracted from three regions of interests (ROIs): GTV; PTV (5.0 mm around the tumor) and LN on pre-operative contrast enhanced computed tomography (CT). LASSO logistic regression method was used to build radiomic signatures. Multivariable regression analysis was used to build a nomogram. The performance of the nomogram was assessed with respect to its calibration, discrimination, and clinical usefulness. The discriminative performance of nomogram was validated both internally and externally. The radiomic signatures using the features of GTV, PTV and LN showed a good ability in predicting LN metastasis with an area under the curve (AUC) of 0.74 (95% CI 0.60–0.88), 0.72 (95% CI 0.57–0.87) and 0.64 (95% CI 0.48–0.80) respectively in external validation cohort. The integration of different signature together further increases the discriminatory ability: GTV + PTV (GPTV): AUC 0.75 (95% CI 0.61–0.89) and GPTV + LN: AUC 0.76 (95% CI 0.61–0.91) in external validation cohort. An integrative nomogram of clinical parameters and radiomic features demonstrated further increase in discriminatory ability with AUC of 0.79 (95% CI 0.66–0.93) in external validation cohort. The nomogram showed good calibration. Decision curve analysis demonstrated that the radiomic nomogram was clinically useful. The integration of information from clinical parameters along with CT radiomics information from GTV, PTV and LN was feasible and increases the predictive performance of the nomogram in predicting LN status in cT1N0M0 adenocarcinoma patients suggesting merit of information integration from multiple sources in building prediction model.

Video-assisted versus open thoracotomy lobectomy: comparison on lymphadenectomy and survival in early stage of lung cancer

Background

Video-assisted thoracic surgery (VATS) is increasingly used in the surgical treatment of early lung cancer, but the oncological benefits are still controversial. We aimed to compare video-assisted lobectomy and open thoracotomy lobectomy in terms of lymphadenectomy and long-term survival depending on the location of lobectomy.

Methods

A retrospective, multicenter study was based on the Polish Lung Cancer Study Group and included patients with stage I lung cancer who were surgically treated between 2007 and 2015. We included 1410 patients after video-assisted lobectomy and 4,855 after open thoracotomy.

Results

The average number of lymph nodes removed in video-assisted lobectomy was 10.9 and in open thoracotomy lobectomy was 12.9 (P<0.001). The 5-year survival was better in the video-assisted lobectomy group (78.6%) compared to open thoracotomy (73.8%) (P=0.002). Significant differences were found in the case of left lower lobe and left upper lobe lobectomies. Multivariable analysis showed that the prognostic factors for open thoracotomy relative to video-assisted lobectomy are: age over 60 [HR (95% CI): 1.55 (1.17-2.05), P=0.002], female [HR (95% CI): 1.57 (1.07-2.29), P=0.02], squamous cell carcinoma [HR (95% CI): 1.63 (1.12-2.37), P=0.011], left lower lobe [HR (95% CI): 2.69 (1.37-5.27), P=0.004] and left upper lobe [HR (95% CI): 1.53 (1.01-2.33), P=0.047].

Conclusions

The study showed that the number of lymph nodes removed during video-assisted lobectomy is significantly lower than in the open thoracotomy group. The long-term video-assisted lobectomy results were significantly better compared to open thoracotomy. Better long-term results were achieved on the left side of lobectomy.

Radiomics: an overview in lung cancer management-a narrative review

Radiomics is a novel approach for optimizing the analysis massive data from medical images to provide auxiliary guidance in clinical issues. Quantitative feature extraction is one of the critical steps of radiomics. The association between radiomics features and the clinicopathological information of diseases can be identified by several statistics methods. For instance, although significant progress has been made in the field of lung cancer, too many questions remain, especially for the individualized decisions. Radiomics offers a new tool to encode the characteristics of lung cancer which is the leading cause of cancer-related deaths worldwide. Here, we reviewed the workflow and clinical utility of radiomics in lung cancer management, including pulmonary nodules detection, classification, histopathology and genetics evaluation, clinical staging, therapy response, and prognosis prediction. Most of these studies showed positive results, indicating the potential value of radiomics in clinical practice. The implementation of radiomics is both feasible and invaluable, and has aided clinicians in ascertaining the nature of a disease with greater precision. However, it should be noted that radiomics in its current state cannot completely replace the work of therapists or tissue examination. The potential future trends of this modality were also remarked. More efforts are needed to overcome the limitations identified above in order to facilitate the widespread application of radiomics in the reasonably near future.

Nodal Involvement Pattern in Clinical Stage IA Non-Small Cell Lung Cancer According to Tumor Location

PURPOSE

The purpose of this study was to investigate lymph node involvement pattern in clinical stage IA non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Clinical stage ⅠA NSCLC patients who underwent lobectomy and lymph node resection were included in this retrospective study. Mediastinal lymph node involvement was distinguished by different lobes and tumor size.

RESULTS

From 2000 to 2015, a total of 759 patients were identified: 282 (37.2%) with tumors in the right upper lobe (RUL), 183 (24.1%) in the left upper lobe (LUL), 124 (16.3%) in the right lower lobe (RLL), 103 (13.6%) in the left lower lobe (LLL), and 67 (8.8%) in the right middle lobe (RML). Patients with tumor size ≤1 cm accounted for 19.6%, >1 and ≤2 cm for 47.8%, >2 and ≤3 cm for 32.5%. Patients with pN1 accounted for 8.2%, and pN2 for 12.5%. Among patients with pN2, the inferior mediastinum was involved in 9.7% of RULs and 17.4% of LULs; the superior mediastinum was involved in 52.2% of RLLs and 36.4% of LLLs. Mediastinal lymph node metastasis was found in 13.2% of patients with size >1 and ≤2 cm, and 19.0% of >2 and ≤3 cm. Patients with tumors ≤1 cm had no N2 lymph node involved.

CONCLUSION

Selective lymph node dissection based on tumor location is not recommended in clinical stage ⅠA NSCLC, and systemic lymph node dissection should be performed for NSCLC with size >1 cm.

Development of a nomogram for preoperative prediction of lymph node metastasis in non-small cell lung cancer: a SEER-based study

Background

Lymph node dissection is an important part of lung cancer surgery. Preoperational evaluation of lymph node metastases decides which dissection pattern should be chosen. The present study aimed to develop a nomogram to predict lymph node metastases on the basis of clinicopathological features of non-small cell lung cancer (NSCLC) patients.

Methods

A total of 35,138 patients diagnosed with NSCLC from 2010–2015 were selected from the Surveillance, Epidemiology, and End Results (SEER) database. Patients were randomly divided into training cohort and validation cohort. Possible risk factors were included and analyzed by logistic regression models. A nomogram was then constructed and validated.

Results

21.83% of all patients were confirmed with positive lymph node metastasis. Age at diagnosis, sex, stage, T status, tumor size, grade and laterality were identified as predicting factors for lymph node involvement. These variables were included to build the nomogram. The AUC of the model was 0.696 (95% CI, 0.617 to 0.775). The model was further validated in the validation set with AUC 0.693 (95% CI, 0.628 to 0.758). The model presented with good prediction accuracy in both training cohort and validation cohort.

Conclusions

We developed a convenient clinical prediction model for regional lymph node metastases in NSCLC patients. The nomogram will help physicians to determine which patients will receive the most benefit from lymph node dissection.

The choice of dissection or preservation of the inferior pulmonary ligament after an upper lobectomy: a systematic review and meta-analysis

BACKGROUND

The necessity of the inferior pulmonary ligament (IPL) dissection after an upper lobectomy remains controversial. This meta-analysis aimed to evaluate whether this accessional procedure could reduce the postoperative complications and improve outcomes.

METHODS

PubMed, Embase, Ovid, Cochrane Library, CBM, and CNKI databases were searched for the relevant studies which compared the dissection with preservation of IPL during the upper lobectomy. The Review Manager 5.3 software was used for this meta-analysis.

RESULTS

Three RCTs and five CCTs were included in this meta-analysis. These studies contained a total of 610 patients, in which 315 patients received a pulmonary ligament dissection (group D) after the upper lobectomy, while the other 295 patients preserved the pulmonary ligament (group P). No significant difference was demonstrated between the group D and group P in terms of drainage time after surgery (MD 0.14, 95%CI - 0.05 to 0.33, P = 0.15), rate of postoperative dead space (OR 1.33, 95%CI 0.72 to 2.46, P = 0.36), rate of postoperative complications (OR 1.20, 95%CI 0.66 to 2.19, P = 0.56). However, the pooled comparison revealed a greater change of the right main bronchial angle (MD 5.00, 95%CI 1.68 to 8.33, P = 0.003) in group D compared with group P, indicated that the dissection of IPL may lead to a greater distortion of bronchus.

CONCLUSIONS

This meta-analysis confirmed that the dissection of IPL do not effectively reduce the postoperative complications and improve the prognosis. Therefore, it is not necessary to dissect the IPL after an upper lobectomy.

Development of a predictive radiomics model for lymph node metastases in pre-surgical CT-based stage IA non-small cell lung cancer

OBJECTIVES

To develop and validate predictive models using clinical parameters, radiomic features and a combination of both for lymph node metastasis (LNM) in pre-surgical CT-based stage IA non-small cell lung cancer (NSCLC) patients.

METHODS

This retrospective study included 649 pre-surgical CT-based stage IA NSCLC patients from our hospital. One hundred and thirty-eight (21 %) of the 649 patients had LNM after surgery. A total of 396 radiomic features were extracted from the venous phase contrast enhanced computed tomography (CECT). The training group included 455 patients (97 with and 358 without LNM) and the testing group included 194 patients (41 with and 153 without LNM). The least absolute shrinkage and selection operator (LASSO) algorithm was used for radiomic feature selection. The random forest (RF) was used for model development. Three models (a clinical model, a radiomics model, and a combined model) were developed to predict LNM in early stage NSCLC patients. The area under the receiver operating characteristic (ROC) curve (AUC) value and decision curve analysis were used to evaluate the performance in LNM status (with or without LNM) using the three models.

RESULTS

The ROC analysis (also decision curve analysis) showed predictive performance for LNM of the radiomics model (AUC values for training and testing, respectively 0.898 and 0.851) and of the combined model (0.911 and 0.860, respectively). Both performed better than the clinical model (0.739 and 0.614, respectively; delong test p-values both<0.001).

CONCLUSION

A radiomics model using the venous phase of CE-CT has potential for predicting LNM in pre-surgical CT-based stage IA NSCLC patients.

The incidence of lymph node metastasis in patients with different oncogenic driver mutations among T1 non-small-cell lung cancer

OBJECTIVE

To investigate the incidence and distribution of lymph node metastasis in patients with different gene mutations among pathological T1 non-small-cell lung cancers (NSCLC).

METHODS

NSCLC cases resected in our institution between 2016 and 2018 were included. Driver mutation testing was performed in all resected tumor tissues. These patients were grouped by the type of gene mutations. On the basis of protein that mutant-genes encoded involved in the molecular pathway, the genotypes were further classified into four distinct groups: upstream receptor mutant protein (EGFR, HER2 and MET); downstream regulator mutant protein (KRAS and BRAF); fusion mutant protein (ROS1, ALK and RET) and the wild type group. The incidence of lymph node metastasis was compared among different groups.

RESULTS

Of the 1052 patients enrolled, the frequency of positive mutations was 68.0%. The incidence of lymph node metastasis were as follows: wild type (19.3%), ROS1 (72.8%), BRAF (55.5%), ALK (44.7%), HER2 (40%), RET (23.1%), KRAS (15.3%), EGFR (15.3%) and MET mutation (0%) (P < 0.001). The incidence of lymph node metastasis was significantly higher in fusion mutant protein group (45.1%) compared with others (wild type 19.3%, downstream regulator mutant protein 19.1%, upstream receptor mutant protein 15.3%, all P < 0.001). Patients with fusion genes also showed higher proportion of vascular invasion and positive lymph node ratio of greater than 0.33 compared to others.

CONCLUSION

Different genotypes of NSCLC have different propensity to develop lymph node metastasis. Cases of fusion gene mutations had a higher risk and burden of lymph node metastasis than other genotypes, which may indicate that more intensive treatment or surveillance strategies should be applied for these patients.

Predictors and survival impact of station 4L metastasis in left non-small cell lung cancer

BACKGROUND

It remains unclear about the predictors and survival impact of station 4L metastasis in left-sided non-small cell lung cancer (NSCLC). This study aims to investigate these issues to explore the significance of station 4L lymph-node dissection (LND).

METHODS

We retrospectively enrolled 405 patients with station 4L LND, and divided them into the positive station 4L metastasis group and the negative station 4L metastasis group. The logistic regression was performed to identify the predictors of station 4L metastasis. The survival outcomes including disease-free survival (DFS) and overall survival (OS) were analyzed in pN2 patients to explore the prognostic effect of station 4L metastasis.

RESULTS

There were 48 (11.9%) patients in the positive station 4L metastasis group and 357 (88.1%) patients in the negative station 4L metastasis group. Station 5 metastasis (P = 0.008, OR 7.578, 95% CI 1.710-33.589), station 10 metastasis (P = 0.004, OR 7.133, 95% CI 1.904-26.717), and cN2 (P = 0.010, OR 5.062, 95% CI 1.473-17.392) were independent risk factors of station 4L metastasis. In pN2 patients, the positive station 4L metastasis group had inferior DFS (P = 0.019) and OS (P = 0.006) compared with the negative station 4L metastasis group, and station 4L metastasis was the independent risk factor for poor prognosis.

CONCLUSION

It is of great necessity to perform station 4L LND in left NSCLC, because station 4L metastasis is not rare and has an unfavorable prognosis.

Combined Off-Pump Coronary Artery Bypass Grafting and Lung Resection in Patients with Lung Cancer Accompanied by Coronary Artery Disease

Introduction

Optimal surgical approach for the treatment of resectable lung cancer accompanied by coronary artery disease (CAD) remains a contentious issue. In this study, we present our cases that were operated simultaneously for concurrent lung cancer and CAD.

Methods

Simultaneous off-pump coronary artery bypass surgery (OPCABG) and lung resection were performed on 10 patients in our clinic due to lung cancer accompanied by CAD. Demographic features of patients, operation data and postoperative results were evaluated retrospectively.

Results

Mean patient age was 63.3 years (range 55-74). All patients were male. Six cases of squamous cell carcinoma, three of adenocarcinoma and one case of large cell carcinoma were diagnosed. Six patients had single-vessel CAD and 4 had two-vessel CAD. Three patients underwent OPCABG at first and then lung resection. The types of resections were one right pneumonectomy, three right upper lobectomies, one right lower lobectomy, three left upper lobectomies, and two left lower lobectomies. Reoperation was performed in one patient due to hemorrhage. One patient developed intraoperative contralateral tension pneumothorax. One patient died due to acute respiratory distress syndrome at the early postoperative period.

Conclusion

Simultaneous surgery is a safe and reliable option in the treatment of selected patients with concurrent CAD and operable lung cancer.

Tumor necrosis factor superfamily 15 promotes lymphatic metastasis via upregulation of vascular endothelial growth factor-C in a mouse model of lung cancer

Lymphatic metastasis is facilitated by lymphangiogenic growth factor vascular endothelial growth factor-C (VEGFC) that is secreted by some primary tumors. We previously identified tumor necrosis factor superfamily 15 (TNFSF15), a blood vascular endothelium-derived cytokine, in lymphatic endothelial cells, as a key molecular modulator during lymphangiogenesis. However, the effect of TNFSF15 on tumor lymphatic metastasis and the underlying molecular mechanisms remain unclear. We report here that TNFSF15, which is known to inhibit primary tumor growth by suppressing angiogenesis, can promote lymphatic metastasis through facilitating lymphangiogenesis in tumors. Mice bearing tumors induced by A549 cells stably overexpressing TNFSF15 exhibited a significant increase in densities of lymphatic vessels and a marked enhancement of A549 tumor cells in newly formed lymphatic vessels in the primary tumors as well as in lymph nodes. Treatment of A549 cells with TNFSF15 results in upregulation of VEGFC expression, which can be inhibited by siRNA gene silencing of death domain-containing receptor-3 (DR3), a cell surface receptor for TNFSF15. In addition, TNFSF15/DR3 signaling pathways in A549 cells include activation of NF-κB during tumor lymphangiogenesis. Our data indicate that TNFSF15, a cytokine mainly produced by blood endothelial cells, facilitates tumor lymphangiogenesis by upregulating VEGFC expression in A549 cells, contributing to lymphatic metastasis in tumor-bearing mice. This finding also suggests that TNFSF15 may have potential as an indicator for prognosis evaluation.

Extranodal extension of nodal metastases is a poor prognostic moderator in non-small cell lung cancer: a meta-analysis

Extranodal extension (ENE) of nodal metastasis is defined as the extension of metastatic cells through the nodal capsule into the perinodal tissue. This morphological parameter, recently proposed as an important prognostic factor in different types of malignancy, has not been included in the TNM staging system for non-small cell lung cancer (NSCLC). In this systematic review with meta-analysis, we weighted the prognostic role of ENE in patients with lymph node-positive NSCLC. Two independent authors searched SCOPUS and PubMed through 28 February 2017. Prospective and retrospective studies on NSCLC, comparing patients with presence of ENE (ENE+) ENE+) vs. only intranodal extension (ENE-) and including data regarding prognosis, were considered as eligible. Data were summarized using risk ratios (RR) for the number of deaths/recurrences, and hazard ratios (HR) with 95% confidence intervals (CI) for time-dependent risk related to ENE+, adjusted for potential confounders. We identified 13 studies, including 1709 patients (573 ENE+ and 1136 ENE-) with a median follow-up of 60 months. ENE was associated with a significantly increased risk of mortality of all causes (RR = 1.39, 95% CI: 1.18-1.65, P < 0.0001, I2 = 70%; HR = 1.30, 95% CI: 1.01-1.67, P = 0.04, I2 = 0%) and of disease recurrence (RR = 1.32, 95% CI: 1.04-1.68, P = 0.02, I2 = 42%; HR = 1.93, 95% CI: 1.53-2.44, P < 0.0001, I2 = 0%). We conclude that in NSCLC, requirements for assessment of ENE should be included in gross sampling and ENE status should be included in the pathology report. Inclusion of ENE status in oncology staging systems will allow further assessment of its role as prognostic parameter.

Selective versus systematic lymph node dissection (other than sampling) for clinical N2-negative non-small cell lung cancer: a meta-analysis of observational studies

Background

The proper extent of lymph node dissection is still controversial. Hence, we compared the clinical efficacy between two strategies of lymph node dissection [selective lymph node dissection (SLND) and systematic lymph node dissection (LND)] for clinical N2-negative non-small cell lung cancer (NSCLC) patients.

Methods

After searching five databases, six cohort studies were eligible for this meta-analysis and the primary endpoint was overall survival (OS). In order to provide a comprehensive perspective, we estimated some perioperative outcomes as well. Either fixed effect or random effects model were properly selected to evaluate the data according to the heterogeneity of included studies.

Results

A total of 7,333 patients with clinical N2-negative NSCLC patients were analyzed for OS. The pooled results demonstrated that LND did not improve survival in OS [hazard ratio (HR) =1.05, 95% confidence interval (CI): 0.82-1.34, P=0.69] compared with SLND. In accordance with OS, there is no significant difference in DFS between LND and SLND (HR =0.98, 95% CI: 0.78-1.23, P=0.87). Moreover, SLND could significantly reduce the operative time [mean difference (MD) =-21.45, 95% CI: -29.53 to -13.36, P<0.001] and blood loss (MD =-28.88, 95% CI: -44.38 to -13.39, P<0.001). Both postoperative morbidity and recurrence showed no significant between two groups.

Conclusions

SLND is an alternative to LND for clinical N2-negative NSCLC patients, which may even provide clinical benefits. However, more randomized controlled trials (RCTs) are expected to determine whether SLND is valid and practical to become a standard procedure of surgical treatment for early-stage NSCLC patients.