Systematic lymphadenectomy versus sampling of ipsilateral mediastinal lymph-nodes during lobectomy for non-small-cell lung cancer: a systematic review of randomized trials and a meta-analysis

Application of tissue pneumoperitoneum technique around lymph nodes in thoracoscopic lung cancer resection

Background

Thoracoscopic surgery is a primary treatment for lung cancer, with lobectomy and mediastinal lymph node dissection being the predominant surgical approaches for invasive lung cancer. While many thoracic surgeons can proficiently perform lobectomy, thorough and standardized lymph node dissection remains challenging. This study aimed to explore a safer and more efficient surgical method for mediastinal lymph node dissection in lung cancer.

Methods

A prospective randomized controlled study was conducted, involving 100 patients with right lung cancer who were admitted to our hospital from January 2021 to April 2024 and met the inclusion criteria. These patients were randomly divided into an observation group (tissue pneumoperitoneum technique around lymph nodes group) and a control group (conventional surgery group). Thoracoscopic lobectomy and mediastinal lymph node dissection were performed. Intraoperative and postoperative related indicators were observed to validate the effectiveness and safety of the tissue pneumoperitoneum technique around lymph nodes.

Results

The observation group showed a significantly shorter lymph node dissection surgery time compared to the control group, with a statistically significant difference (p < 0.05). The number of lymph nodes dissected in the observation group was significantly higher than that in the control group, with a statistically significant difference (p < 0.05). Although the observation group had slightly more mediastinal lymph node stations dissected than the control group, the difference was not statistically significant (p > 0.05). The total drainage volume within three days postoperatively was comparable between the two groups, with no statistically significant difference (p > 0.05). The observation group had shorter chest tube indwelling time and postoperative hospital stay than the control group, with statistically significant differences (p < 0.05). The incidence of surgical complications was similar between the two groups, and there were no perioperative deaths.

Conclusion

The tissue pneumoperitoneum technique around lymph nodes is a more efficient method for mediastinal lymph node dissection in lung cancer, demonstrating safety and feasibility, and is worthy of promotion.

Protocol for a systematic review and meta-analysis of recurrence and metastasis of different surgical techniques for non-small cell lung cancer

INTRODUCTION

Lung cancer remains the primary cause of cancer-related deaths on a global scale. Surgery is the main therapeutic option for non-small cell lung cancer (NSCLC). However, the optimal surgical approach for lymph node assessment in NSCLC resection remains controversial, and it is still uncertain whether lymph node dissection (LND) is more effective in reducing recurrence and metastasis rates in NSCLC compared with lymph node sampling (LNS). Therefore, we will conduct a meta-analysis to evaluate the recurrence and metastasis of LND versus LNS in patients with NSCLC.

METHODS AND ANALYSIS

This systematic review and meta-analysis will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analysis: The PRISMA Statement. According to the predefined inclusion criteria, we will conduct a comprehensive search for randomised controlled trials and non-randomised studies examining the recurrence and metastasis of LND compared with LNS in patients with NSCLC. A literature search from inception in PubMed, EMBASE, the Cochrane Library, CNKI, Wanfang, SINOMED, VIP and Web of Science will be done. There will be no limitations on language, and the search will be undertaken on 30 August 2024, with regular search for new studies. Additionally, relevant literature references will be retrieved and hand-searching of pertinent journals will be conducted. The main outcomes include overall recurrence rate, local recurrence rate and distant metastasis rate. The supplementary outcomes encompass the rates of regional recurrence and lymph node metastasis. Two independent reviewers will perform screening, data extraction and quality assessment. Our reviewers will perform subgroup analysis, sensitivity analysis and publication bias analysis to evaluate the heterogeneity and robustness. Review Manager 5.4 will be applied in analysing and synthesising. The Grading of Recommendations Assessment, Development and Evaluation will be used to assess the quality of evidence for the whole study.

ETHICS AND DISSEMINATION

Ethical approval is dispensable for this study since no private information of the participants will be involved. The findings of the present study will be disseminated through a peer-reviewed journal or conference presentation.

STUDY REGISTRATION

The protocol of the systematic review has been registered on Open Science Framework, with a registration doi: https://doi.org/10.17605/OSF.IO/S2FT5.

A comparison of three-port and four-port Da Vinci robot-assisted thoracoscopic surgery for lung cancer: a retrospective study

BACKGROUND

At present, research comparing the short-term postoperative outcomes of anatomical resection in lung cancer under different ports of da Vinci robot-assisted surgery is insufficient. This report aimed to compare the outcomes of three-port and four-port da Vinci robot-assisted thoracoscopic surgery for radical dissection of lung cancer.

METHODS

171 consecutive patients who presented to our hospital from January 2020 to October 2021 with non-small cell lung cancer and treated with da Vinci robot-assisted thoracoscopic surgery for radical resection of lung cancer were retrospectively collected and divided into the three-port group (n = 97) and the four-port group (n = 74). The general clinical data, perioperative data and life quality were individually compared between the two groups.

RESULTS

All the 171 patients successfully underwent surgeries. Compared to the four-port group, the three-port group had comparable baseline characteristics in terms of age, sex, tumor location, tumor size, history of chronic disease, pathological type, and pathological staging. The three-port group also had shorter operation time, less intraoperative blood loss, lower chest tube drainage volume, shorter postoperative hospitalization stay durations, but showed no statistically significant difference (P > 0.05). Postoperative 24, 48 and 72 h visual analogue scale pain scores were lower in the three-port group (p < 0.001). No significant difference was observed between the two groups in the hospitalization costs (P = 0.664), number or stations of total lymph node dissected (p > 0.05) and postoperative respiratory complications (P > 0.05).

CONCLUSIONS

The three-port robot-assisted thoracoscopic surgery is safe and effective and took better outcomes than the four-port robot-assisted thoracoscopic surgery in non-small cell lung cancer.

Recent Advancements in Minimally Invasive Surgery for Early Stage Non-Small Cell Lung Cancer: A Narrative Review

Introduction: Lung cancer remains a global health concern, with non-small cell lung cancer (NSCLC) comprising the majority of cases. Early detection of lung cancer has led to an increased number of cases identified in the earlier stages of NSCLC. This required the revaluation of the NSCLC treatment approaches for early stage NSCLC. Methods: We conducted a comprehensive search using multiple databases to identify relevant studies on treatment modalities for early stage NSCLC. Inclusion criteria prioritized, but were not limited to, clinical trials and meta-analyses on surgical approaches to early stage NSCLC conducted from 2021 onwards. Discussion: Minimally invasive approaches, such as VATS and RATS, along with lung resection techniques, including sublobar resection, have emerged as treatments for early stage NSCLC. Ground-glass opacities (GGOs) have shown prognostic significance, especially when analyzing the consolidation/tumor ratio (CTR). There have also been updates on managing GGOs, including the non-surgical approaches, the extent of lung resection indicated, and the level of lymphadenectomy required. Conclusions: The management of early stage NSCLC requires a further assessment of treatment strategies. This includes understanding the required extent of surgical resection, interpreting the significance of GGOs (specifically GGOs with a high CTR), and evaluating the efficacy of alternative therapies. Customized treatment involving surgical and non-surgical interventions is essential for advancing patient care.

Analysis of related factors and treatment effect of chylothorax after lung surgery

Background

Chylothorax is a seldom encountered complication following lung surgery. However, due to the widespread practice of lung surgery, postoperative complications have inevitably arisen. Chylothorax significantly affects a patient's discharge and recovery. This study investigates the risk factors for postoperative chylothorax at our center and analyzes various treatment modalities and prognostic outcomes.

Methods

A retrospective analysis was conducted on all postoperative lung resections performed between January 2018 to August 2021 that met the inclusion criteria. Inclusion criteria covered patients undergoing various thoracic surgeries for lung conditions, while exclusion criteria included postoperative referrals for surgeries unrelated to lung tumors.

Results

Postoperative chylothorax occurred in 42 of 5,706 patients after lung surgery. General information and disease-related data of the chylothorax and control group were analyzed by univariate and multivariate analyses. Multivariate analysis showed that serum albumin before surgery [odds ratio (OR) =0.86, 95% confidence interval (CI): 0.81-0.91, P<0.001], γ-glutamyl transferase level before surgery (after logarithmic transformation, OR =1.01, 95% CI: 1.00-1.01, P=0.01), squamous cell carcinoma (OR =2.77, 95% CI: 1.37-5.6, P=0.008), right mediastinal lymph node dissection (OR =3.15, 95% CI: 1.62-6.14, P<0.001) were independent risk factors for postoperative chylothorax. Among the 42 cases of postoperative chylothorax, 26 patients were improved with conservative treatments, and 6 patients were improved with chemical pleurodesis. Eight patients with postoperative chylothorax underwent thoracoscopic thoracic duct ligation. Three patients experienced severe postoperative complications: one was discharged after prolonged treatment, while the remaining two either succumbed or were discharged against medical advice.

Conclusions

The incidence of chylothorax after lung surgery closely correlates with the intraoperative trauma and nutritional status of patients during the perioperative period. The majority of patients with postoperative chylothorax experienced relief through conservative measures, somatostatin administration, and chemical pleurodesis. Nevertheless, substantial postoperative chylothorax necessitated surgical intervention, involving thoracic duct ligation or drug pleurodesis.

Metastatic pathways to the lower zone by segment in patients with clinical T1 lower lobe non-small cell lung cancer

OBJECTIVE

Segmentectomy and mediastinal lymph node dissection (LND) may increasingly be used for non-small cell lung cancer (NSCLC). Lymph node metastasis (LNM) distribution varies by lower lobe segments; however, its segment-specific spread to the lower zone (#8, 9) (LZ) in lower lobe NSCLC is seldom reported.

METHODS

In total, 352 patients with clinical T1 lower lobe NSCLC who underwent lobectomy with systematic or lobe-specific LND were included for analysis between January 2006 and December 2018.

RESULTS

Fifty-eight (16.2%) patients had LNM (pN1: 24, pN2: 34), and nine (2.6%) had LZ metastasis. LZ metastasis was significantly more frequent in tumors with diameter > 2 cm, tumors without ground-glass opacity on radiological findings, left lung cancer, and basal segment lung cancer (respectively, p = 0.039, 0.006, 0.0177, 0.0024). None of the S6 NSCLC patients had LZ metastasis. Two patients with right basal segment NSCLC had LZ metastases (tumor on S10) as well as N1 lymph node and subcarinal zone metastasis. Seven (8.4%) patients with left basal segment NSCLC had LZ metastasis (tumor on S8: 3, tumor on S10: 4). Of them, three patients with left basal NSCLC had isolated LZ metastasis.

CONCLUSIONS

The LND of the LZ can be omitted for clinical T1 patients with S6 NSCLC. In addition, the LND of the LZ may be omitted in right basal NSCLC if intraoperative confirmation of negative N1 and subcarinal zone lymph nodes is obtained; however, it is necessary for left basal segment NSCLC.

Enhanced Survival with Lymphadenectomy in Early-Stage Metachronous Second Primary Lung Cancer: A Retrospective Analysis

INTRODUCTION

Lymphadenectomy is a cornerstone in the surgical management of resectable primary lung cancer. However, its prognostic significance in early-stage metachronous second primary lung cancer (MSPLC) remains poorly understood. This retrospective study aimed to evaluate the prognostic impact of lymphadenectomy in these patients using data from the Surveillance, Epidemiology, and End Results (SEER) Database.

METHODS

A retrospective cohort study was conducted using data from the SEER Database for patients surgically treated for stage I MSPLC between 2004 and 2015. Propensity score-matching was employed to create comparable cohorts, and the Cox proportional hazards model was utilized to estimate the hazard ratio (HR) for overall survival after lymphadenectomy compared to non-lymphadenectomy. Survival analysis was performed using Kaplan-Meier curves and the log-rank test.

RESULTS

Among 920 identified patients with MSPLC, 574 (62.4%) underwent lymphadenectomy. Propensity score-matching yielded 255 patients in both the lymphadenectomy and non-lymphadenectomy groups. Over a median follow-up of 38 months, the 5-year overall survival probability after a diagnosis of MSPLC was 58.7% in the lymphadenectomy group and 43.9% in the non-lymphadenectomy group (HR: 0.76; 95% confidence interval 0.64-0.90; p = 0.002).

CONCLUSION

In this population-based study, lymphadenectomy is associated with prolonged overall survival in patients with stage I MSPLC. These findings suggest the potential benefit of incorporating lymphadenectomy into the surgical management of MSPLC, providing valuable guidance for thoracic surgeons in clinical decision-making.

Survival outcomes following complete mediastinal lymphadenectomy or selective mediastinal lymphadenectomy in patients with stage I-IIIA non-small cell lung cancer: protocol for a systematic review and meta-analysis

INTRODUCTION

Lung cancer remains the largest cause of cancer-related deaths worldwide. Surgical removal of non-small cell lung cancer (NSCLC) has the potential to achieve a cure, although there is ongoing debate regarding the significance of removing mediastinal nodes and the optimal extent of lymph node excision. The purpose of this research is to assess the survival outcomes in patients diagnosed with stage I-IIIA NSCLC who received either complete mediastinal lymphadenectomy (CML) or selective mediastinal lymphadenectomy (SML).

METHODS AND ANALYSIS

The protocol follows the guidelines recommended in Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols, and this meta-analysis will be conducted in accordance with the standard methodology recommended by the Cochrane Collaboration and reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidance. We will conduct a comprehensive search for randomised controlled trials and non-randomised studies examining the effectiveness of CML compared with SML in patients with stage I-IIIA NSCLC. Two authors will perform a comprehensive search of the MEDLINE/PubMed, Embase, the Cochrane Library, CNKI, WanFang, Sinomed, VIP and Web of Science databases. There will be no restrictions on language or publication date, and the search will be conducted on 10 April 2024, with ongoing searches for new research. Reference lists will also be checked and pertinent journals will be hand searched. The primary outcomes include overall survival (OS) and disease-free survival (DFS), while the secondary outcomes consist of 1-year, 3-year and 5-year OS rates and 1-year, 3-year and 5-year DFS rates. Two independent reviewers will screen, extract data, assess quality and evaluate the potential for bias in the selected research, with a third acting as arbitrator. Subgroup analyses and sensitivity analyses are planned. The quality of the evidence will be evaluated using Grading of Recommendations Assessment, Development and Evaluation. Review Manager V.5.4 will be used for the analysis and synthesis process.

ETHICS AND DISSEMINATION

Ethical review and approval are not necessary for this study because it is based on a secondary analysis of the literature. The results will be submitted for reporting in a peer-reviewed publication.

STUDY REGISTRATION

Open Science Framework (https://doi.org/10.17605/OSF.IO/PN7UQ).

Importance of Lymph Node Evaluation in ≤2-cm Pure-Solid Non-Small Cell Lung Cancer

BACKGROUND

The prevalence of lymph node (LN) metastasis in small-sized lung cancer varies depending on the tumor size and proportion of ground-glass opacity. We investigated occult LN metastasis and prognosis in patients with small-sized non-small cell lung cancer (NSCLC), mainly focusing on the pure-solid tumor.

METHODS

We retrospectively reviewed patients with ≤2-cm clinical N0 NSCLC who underwent lung resection with curative intent from 2003 to 2017. Among them we analyzed patients who also underwent adequate complete systematic LN dissection. Pathologic results and disease-free survival of the radiologically mixed ground-glass nodule (mGGN) and pure-solid nodule (PSN) groups were analyzed.

RESULTS

Of 1329 patients analyzed, 591 had mGGNs and PSNs. As tumor size increased, patients in the mGGN group showed no difference in LN metastasis: ≤1 cm, 2.27%; 1.0 to 1.5 cm, 2.19%; and 1.5 to 2.0 cm, 2.18% (P = .999). However the PSN group showed a significant difference in LN metastasis as the tumor size increased: ≤1 cm, 2.67%; 1.0 to 1.5 cm, 12.46%; and 1.5 to 2.0 cm, 21.31% (P < .001). In the multivariate analysis tumor size was a significant predictor of nodal metastasis in the PSN group but not in the mGGN group. In terms of 5-year disease-free survival, the mGGN group showed a better prognosis than the PSN group (94.4% vs 71.2%, P < .001).

CONCLUSIONS

We need to conduct a thorough LN dissection during surgery for small-sized NSCLC, especially for pure-solid tumors ≥ 1 cm.

Tumor distance from the mediastinum predicts N2 upstaging in clinical stage I lower-lobe non-small cell lung cancer

OBJECTIVE

Pulmonary lymphatic drainage of the lower lobe into the mediastinal lymph nodes includes not only the pathway via the hilar lymph nodes but also the pathway directly into the mediastinum via the pulmonary ligament. This study aimed to determine the association between the distance from the mediastinum to the tumor and the frequency of occult mediastinal nodal metastasis (OMNM) in patients with clinical stage I lower-lobe non-small cell lung cancer (NSCLC).

METHODS

Between April 2007 and March 2022, data of patients who underwent anatomical pulmonary resection and mediastinal lymph node dissection for clinical stage I radiological pure-solid lower-lobe NSCLC were retrospectively reviewed. In computed tomography axial sections, the ratio of the distance from the inner edge of the lung to the inner margin of the tumor within the lung width of the affected lung was defined as the inner margin ratio. Patients were divided into 2 groups based on whether the inner margin ratio was ≤0.50 (inner-type) or >0.50 (outer-type), and the association between inner margin ratio status and clinicopathological findings was assessed.

RESULTS

In total, 200 patients were enrolled in the study. OMNM frequency was 8.5%. More inner-type than outer-type patients had OMNM (13.2% vs 3.2%; P = .012) and skip N2 metastasis (7.5% vs 1.1%; P = .038). Multivariable analysis revealed that the inner margin ratio was the only independent preoperative predictor of OMNM (odds ratio, 4.72; 95% CI, 1.31-17.07; P = .018).

CONCLUSIONS

Tumor distance from the mediastinum was the most important preoperative predictor of OMNM in patients with lower-lobe NSCLC.

A simple nomogram for predicting occult lymph node metastasis of non-small cell lung cancer from preoperative computed tomography findings, including the volume-doubling time

PURPOSE

Latent lymph node metastasis is a clinical concern in the surgical treatment of non-small cell lung cancer (NSCLC). The present study identified a simple tool, including the volume-doubling time (VDT), for evaluating the risk of nodal metastasis.

METHODS

We reviewed, retrospectively, 560 patients who underwent radical resection for cN0M0 NSCLC. The whole tumor VDT and solid component VDT (SVDT) for differentiating the histological type and adenocarcinoma subtype were analyzed and a nomogram was constructed using variables selected through a stepwise selection method. The model was assessed through a calibration curve and decision curve analysis (DCA).

RESULTS

Lymph node metastases were detected in 89 patients (15.9%). The SVDT tended to be longer in patients with adenocarcinoma (294.5 days, p < 0.0001) than in those with other histological types of NSCLC, but was shorter when the solid/micropapillary component was predominant (127.0 days, p < 0.0001). The selected variables (tumor location, solid component diameter, consolidation tumor ratio, SVDT, and carcinoembryonic antigen) demonstrated significant differences and were used for the nomogram. The calibration curve indicated consistency, and the DCA showed validity across most threshold ranges from 0 to 68%.

CONCLUSIONS

The established nomogram is a useful tool for the preoperative prediction of lymph node metastasis, and the SVDT was the most influential factor in the nomogram.

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.

Extent of Lymph Node Dissection in Patients with Small-Sized Peripheral Non-Small Cell Lung Cancer during Intentional Segmentectomy

PURPOSE

Segmentectomy and mediastinal lymph node dissection (MLND) are becoming standard procedures for small-sized (<2 cm) peripheral non-small cell lung cancer (NSCLC). Although the benefits of the less resected lung are proven, the extent of lymph node dissection remains unchanged.

METHODS

We studied 422 patients who underwent lobectomy with MLND (lobe specific or systemic) for small peripheral NSCLC with clinical N0 disease. Patients with middle lobectomy (n = 39) and a consolidation-to-tumor (C/T) ratio ≤0.50 (n = 33) were excluded. We investigated the clinical factors, lymph node metastasis distributions, and lymph node recurrence patterns of 350 patients.

RESULTS

Thirty-five (10.0%) patients had lymph node metastasis; none with C/T ratio <0.75 had lymph node metastasis and lymph node recurrence. None had solitary lymph node metastasis in the outside lobe-specific MLND. Six patients had mediastinal lymph node metastasis at the initial site of recurrence; none had mediastinal lymph node recurrence outside the lobe-specific MLND, except for two patients with S6 primary disease.

CONCLUSION

NSCLC patients with small peripheral tumors and a C/T ratio <0.75 during segmentectomy may not require MLND. The optimal MLND for patients with a C/T ratio ≥0.75, except for those with S6 primary, may be lobe-specific MLND.

Lymph node dissection in small peripheral lung cancer: Supplemental analysis of JCOG0802/WJOG4607L

OBJECTIVE

The optimal region of lymph node dissection (LND) during segmentectomy in patients with small peripheral non-small cell lung cancer requires clarification. Through a supplemental analysis of the Japan Clinical Oncology Group (JCOG) 0802/West Japan Oncology Group (WJOG) 4607L, we investigated the associated factors, distribution, and recurrence pattern of lymph node metastases (LNMs) and proposed the optimal LND region.

METHODS

Of the 1106 patients included in the JCOG0802/WJOG4607L, 1056 patients with LNDs were included in this supplemental analysis. We investigated the distribution and recurrence pattern of LNMs along with the radiologic findings (with ground-glass opacity, part-solid tumor; without ground-grass opacity component, pure-solid tumor).

RESULTS

The radiologic findings were the only significant factor for LNMs. Of 533 patients with part-solid tumors, 8 (1.5%) had LNMs. Further, only 3 (0.5%) patients had pN2 disease, and no patients had interlobar LNMs from nonadjacent segments. Of the 523 patients with pure-solid tumors, 55 (10.5%) had LNMs, and 28 (5.4%) had pN2 disease. Five patients had metastases to nonadjacent interlobar lymph nodes (LNs). Two (2.0%) patients with S6 tumors had upper mediastinal LNMs. In addition, the incidence of mediastinal LN recurrence in patients with S6 lung cancer was greater in those who underwent selective LND than those who underwent systematic LND (P = .0455).

CONCLUSIONS

Nonadjacent interlobar and mediastinal LND have little impact on pathologic nodal staging in patients with part-solid tumors. In contrast, selective LND is recommended at least for patients with pure-solid tumors.

The American Association for Thoracic Surgery (AATS) 2023 Expert Consensus Document: Staging and multidisciplinary management of patients with early-stage non-small cell lung cancer

Novel targeted therapy and immunotherapy drugs have recently been approved for use in patients with surgically resectable lung cancer. Accurate staging, early molecular testing, and knowledge of recent trials are critical to optimize oncologic outcomes in these patients.

The Role of Lymphadenectomy in Early-Stage NSCLC

Lung cancer remains the leading cause of cancer-related death worldwide. The involvement of lymph nodes by the tumor has a strong impact on survival of patients. For this reason, lymphadenectomy plays a crucial role in the staging and prognosis of NSCLC, to define the most appropriate therapeutic strategies concerning the stage of the disease. To date, the benefit, in terms of survival, of the different extents of lymphadenectomy remains controversial in the scientific community. It is recognized that metastatic involvement of mediastinal lymph nodes in lung cancer is one of the most significant prognostic factors, in terms of survival, and it is therefore mandatory to identify patients with lymph node metastases who may benefit from adjuvant therapies, to prevent distant disease and local recurrences. The purpose of this review is to evaluate the role of lymphadenectomy in early-stage NSCLC in terms of efficacy and accuracy, comparing systematic, sampling, and lobe-specific lymph node dissection and analyzing the existing critical issue, through a search of the most relevant articles published in the last decades.

Uniportal VATS for Diagnosis and Staging in Non-Small Cell Lung Cancer (NSCLC)

Uniportal VATS has become an accepted approach in minimally invasive thoracic surgery since its first report for lobectomy in 2011. Since the initial restrictions in indications, it has been used in almost all procedures, from conventional lobectomies to sublobar resections, bronchial and vascular sleeve procedures and even tracheal and carinal resections. In addition to its use for treatment, it provides an excellent approach for suspicious solitary undiagnosed nodules after bronchoscopic or transthoracic image-guided biopsy. Uniportal VATS is also used as a surgical staging method in NSCLC due to its low invasiveness in terms of chest tube duration, hospital stay and postoperative pain. In this article, we review the evidence of uniportal VATS accuracy for NSCLC diagnosis and staging and provide technical details and recommendations for its safe performance for that purpose.

[Prediction of Lymph Node Metastasis of Mixed Ground-glass Nodules Based on Clinical Imaging Information]

BACKGROUND

Previous studies have shown that lymph node metastasis only occurs in some mixed ground-glass nodules (mGGNs) which the pathological results were invasive adenocarcinoma (IAC). However, the presence of lymph node metastasis leads to the upgrading of tumor-node-metastasis (TNM) stage and worse prognosis of the patients, so it is important to perform the necessary evaluation before surgery to guide the operation method of lymph node. The aim of this study was to find suitable clinical and radiological indicators to distinguish whether mGGNs with pathology as IAC is accompanied by lymph node metastasis, and to construct a prediction model for lymph node metastasis.

METHODS

From January 2014 to October 2019, the patients with resected IAC appearing as mGGNs in computed tomography (CT) scan were reviewed. All the lesions were divided into two groups (with lymph node metastasis or not) according to their lymph node status. Lasso regression model analysis by applying R software was used to evaluate the relationship between clinical and radiological parameters and lymph node metastasis of mGGNs.

RESULTS

A total of 883 mGGNs patients were enroled in this study, among which, 12 (1.36%) showed lymph node metastasis. Lasso regression model analysis of clinical imaging information in mGGNs with lymph node metastasis showed that previous history of malignancy, mean density, mean density of solid components, burr sign and percentage of solid components were informative. Prediction model for lymph node metastasis in mGGNs was developed based on the results of Lasso regression model with area under curve=0.899.

CONCLUSIONS

Clinical information combined with CT imaging information can predict lymph node metastasis in mGGNs.

The IASLC Proposed Grading System Accurately Predicts Prognosis and Mediastinal Nodal Metastasis in Patients With Clinical Stage I Lung Adenocarcinoma

The International Association for the Study of Lung Cancer (IASLC) recently proposed a new grading system for lung adenocarcinoma (LUAD). We aimed to validate the prognostic performance of the grading system and explore its role in guiding the strategy of lymph node (LN) dissection. We retrospectively reviewed 1029 patients with clinical stage I LUAD who underwent surgery between 2011 and 2013. The association between mediastinal nodal metastasis and grading system was evaluated. To investigate the value of the grading system in guiding LN dissection strategies, 3 pathologists evaluated the feasibility of identifying the grading system using frozen section (FS). The differences in prognosis between all neighboring grades were highly significant based on the grading system ( P <0.001). Notably, almost no grade 1 LUAD (1.4%) had pN2 disease, whereas higher rates were found in grade 2 LUAD (9.6%) and grade 3 LUAD (18.3%) ( P <0.001). Multivariate logistic regression analysis revealed that higher tumor grade was an independent predictor of mediastinal nodal metastasis ( P =0.002). Moreover, limited mediastinal LN dissection had equivalent prognosis in grade 1 LUAD, but significantly worse prognosis in grade 2 and grade 3 LUAD than systematic mediastinal LN dissection. The overall accuracy of using intraoperative FS to identify the IASLC grading system was 85.4% (κ=0.765) with substantial agreement. The IASLC grading system could accurately stratify prognosis and predict mediastinal nodal metastasis in patients with clinical stage I LUAD. FS was feasible for identifying the IASLC grading system.

Mediastinal lymph node evaluation, especially at station 4L, in left upper lobe lung cancer

Background

Mediastinal lymph node (LN) dissection during lung resection is essential for accurate staging. Station 4L dissection is anatomically difficult. Therefore, care should be taken to avoid complications. We investigated the importance of mediastinal LN dissection in left upper lobe lung cancer and evaluated intraoperative videos to identify relevant steps during dissection.

Methods

We retrospectively reviewed 151 consecutive patients with left upper lobe lung cancer. Finally, 139 patients were enrolled to examine the survival effects of clinical factors of metastatic LN stations. The association between risk factors or surgical procedures and recurrent laryngeal nerve palsy was analyzed.

Results

LN dissection of the left upper lobe revealed station 4L LN metastasis in nine patients, three of whom were node-negative on mediastinoscopy. Station 4L LN status was confirmed intraoperatively in 12 of 33 patients. Twenty patients had recurrent laryngeal nerve palsy, four of whom were complicated with aspiration pneumonia. Station 4L LN dissection was an independent risk factor for recurrent laryngeal nerve palsy (P=0.03). The use of an energy device near the recurrent laryngeal nerve was a significant risk factor for recurrent laryngeal nerve palsy. Incidentally, pathological N stage ≥2 was an independent prognostic factor for disease-free survival (DFS) (P=0.005) herein.

Conclusions

In patients with left upper lobe lung cancer, pathological N2 disease is an important predictor of recurrence. Therefore, accurate mediastinal LN dissection, including at station 4L, should be performed. We propose to standardize the dissection procedure at each institution to avoid complications, such as recurrent laryngeal nerve palsy.

Lung Cancer Management in Low and Middle-Income Countries

Lung cancer is an increasing problem in the developing world due to rising trends in smoking, high incidence of air pollution, lack of awareness and screening, delayed presentation, and diagnosis at the advanced stage. Even after diagnosis, there are disparities in access to health care facilities and inequitable distribution of resources and treatment options. In addition, the shortage of trained personnel and infrastructure adds to the challenges faced by patients with lung cancer in these regions. A multi-pronged effort targeting tobacco cessation, health promotion and awareness, capacity building, and value-based care are the need of the hour.

Surgical Issues for Operable Early-Stage Non-Small-Cell Lung Cancer

Surgical care for early stage non-small-cell lung cancer continuously evolves with new procedures, techniques and care pathways. The most obvious recent change was the transition to minimally invasive procedures, but numerous other aspects of care have also been refined to improve safety and tolerability. These care advancements are essential as we move into an era with increased early detection as a result of screening and greater indications for the use of adjuvant and neoadjuvant strategies.

Controversies in Mediastinal Staging for Nonsmall Cell Lung Cancer

Mediastinal lymph nodal involvement in nonsmall cell lung cancer plays a crucial role in deciding treatment strategy. Survival falls markedly with increasing involvement of mediastinal nodal stations. Hence, accurate staging of the mediastinum with lowest morbidity is of utmost importance. A wide array of invasive and noninvasive modalities that complement each other in assessing the nodes are available at our disposal. Guidelines recommend noninvasive imaging as the initial step in the staging algorithm for all tumors, followed by invasive staging. No single modality has proven to be the ideal method to stage the mediastinum when used alone. In the present decade, minimally invasive endobronchial ultrasound (EBUS) has challenged the position of surgical mediastinoscopy, which has been the gold standard, historically. However, a negative EBUS needs to be confirmed by surgical mediastinoscopy. Video-assisted mediastinoscopic lymphadenectomy has also come to the forefront in last two decades and has shown exceptional results, when performed in experienced centers. This review details the various modalities of mediastinal staging and the controversies surrounding the optimal method of staging, restaging after neoadjuvant therapy, and the most cost-effective strategy.

What Should Thoracic Surgeons Consider during Surgery for Ground-Glass Nodules?: Lymph Node Dissection

Thoracic surgeons need to be aware of several important points regarding intraoperative lymph node dissection during surgery for non-small cell lung cancer with ground-glass opacities. The first point relates to the need for lymph node dissection during sublobar resection. Since even patients undergoing sublobar resection may benefit from lymph node dissection, it should be selectively performed according to adequate indications, which require further study. Second, there seems to be no difference in postoperative morbidity between systematic sampling and systematic dissection, but the survival benefit from systematic dissection remains unclear. The results of randomized controlled trials on this topic are conflicting, and their evidence is jeopardized by a high risk of bias in terms of the study design. Therefore, further randomized controlled trials with a sound design should investigate this issue. Third, more favorable survival outcomes tend to be positively associated with the number of examined lymph nodes. Minimum requirements for the number of examined lymph nodes in non-small cell lung cancer should be defined in the future. Finally, lobe-specific lymph node dissection does not have a negative prognostic impact. It should not be routinely performed, but it can be recommended in selected patients with smaller, less invasive tumors. Results from an ongoing randomized controlled trial on this topic should be awaited.

Guiding Principles in the Management of Synchronous and Metachronous Primary Non-Small Cell Lung Cancer

Multiple lung cancers can be found simultaneously, with incidence ranging from 1% to 8%. Documentation of more than 1 pulmonary lesion can be challenging, because these solid, ground-glass, or mixed-density tumors may represent multicentric malignant disease or intrapulmonary metastases. If mediastinal nodal and distant deposits are excluded, surgery should be contemplated. After surgical treatment of lung cancer, patients should be followed closely for an undetermined period of time. Good clinical judgment is of outmost importance in deciding which individuals will benefit from those surgical interventions and which are candidates for alternate therapies. Every case should be discussed in a multidisciplinary meeting.

The Role of Surgery in Lung Cancer Treatment: Present Indications and Future Perspectives-State of the Art

Non-small cell lung cancers (NSCLC) are different today, due to the increased use of screening programs and of innovative systemic therapies, leading to the diagnosis of earlier and pre-invasive tumors, and of more advanced and controlled metastatic tumors. Surgery for NSCLC remains the cornerstone treatment when it can be performed. The role of surgery and surgeons has also evolved because surgeons not only perform the initial curative lung cancer resection but they also accompany and follow-up patients from pre-operative rehabilitation, to treatment for recurrences. Surgery is personalized, according to cancer characteristics, including cancer extensions, from pre-invasive and local tumors to locally advanced, metastatic disease, or residual disease after medical treatment, anticipating recurrences, and patients' characteristics. Surgical management is constantly evolving to offer the best oncologic resection adapted to each NSCLC stage. Today, NSCLC can be considered as a chronic disease and surgery is a valuable tool for the diagnosis and treatment of recurrences, and in palliative conditions to relieve dyspnea and improve patients' comfort.

The Evolving Concept of Complete Resection in Lung Cancer Surgery

Simple Summary

In the surgical treatment of lung cancer, the complete removal of the portion of the lung where the cancer is and of the involved adjacent structures is of paramount importance to achieve long-term survival. The International Association for the Study of Lung Cancer (IASLC) proposed a definition of complete resection that included a well-defined type of removal of the regional lymph nodes as a fundamental step. The lymph nodes may contain cancer cells and, if left behind, cancer will soon progress. The IASLC also defined incomplete resection when there is any evidence of persistent cancer after the operation. It also defined an intermediate condition, uncertain resection, when no evidence of residual disease can be proved, but all the conditions of complete resection are not fulfilled. Four validations of the definitions have proved their prognostic value and, therefore, the definitions should be followed when a surgical resection of lung cancer is planned.

Abstract

Different definitions of complete resection were formulated to complement the residual tumor (R) descriptor proposed by the American Joint Committee on Cancer in 1977. The definitions went beyond resection margins to include the status of the visceral pleura, the most distant nodes and the nodal capsule and the performance of a complete mediastinal lymphadenectomy. In 2005, the International Association for the Study of Lung Cancer (IASLC) proposed definitions for complete, incomplete and uncertain resections for international implementation. Central to the IASLC definition of complete resection is an adequate nodal evaluation either by systematic nodal dissection or lobe-specific systematic nodal dissection, as well as the integrity of the highest mediastinal node, the nodal capsule and the resection margins. When there is evidence of cancer remaining after treatment, the resection is incomplete, and when all margins are free of tumor, but the conditions for complete resection are not fulfilled, the resection is defined as uncertain. The prognostic relevance of the definitions has been validated by four studies. The definitions can be improved in the future by considering the cells spread through air spaces, the residual tumor cells, DNA or RNA in the blood, and the determination of the adequate margins and lymphadenectomy in sublobar resections.

Pulmonary metastasectomy: limits to credibility

Lung metastases are a common site of spread for many malignant tumours. Pulmonary metastasectomy has been practiced for many years for sarcomas and is now becoming increasingly frequently advocated for patients with many other tumours, especially colorectal cancer. In this article we argue that this procedure is one framed by therapeutic opportunity and not supported by strong evidence. It is potentially harmful and may not be effective. Our argument is based on several important issues: (I) the vagueness of the concept of "oligometastases" and its biological implausibility; (II) the flaws in the often-cited observational evidence, especially selection bias; (III) the lack of any reliable randomised trial evidence of improved survival but evidence of harm; (IV) the failure of strategies to detect metastases earlier to influence overall survival. The introduction of stereotactic radiotherapy and image-guided thermal ablation have made the urge to treat lung metastases stronger but without any good evidence to justify their use. We acknowledge the problems of carrying out randomised trials when there is a clear lack of equipoise in the clinical teams involved but believe that there is an ethical need to do so. Many patients are probably being given false hope of cure or prolonged survival but are at risk of harm from pulmonary metastasectomy or ablation. It is possible that a few patients may benefit but without better evidence we do not know which, if any, do.

Impact of a Lymph Node Specimen Collection Kit on the Distribution and Survival Implications of the Proposed Revised Lung Cancer Residual Disease Classification: A Propensity-Matched Analysis

IMPORTANCE

The International Association for the Study of Lung Cancer (IASLC) has proposed a revision of the residual disease (R-factor) classification, to R0, 'R-uncertain', R1 and R2. We previously demonstrated longer survival after surgical resection with a lymph node specimen collection kit, and now evaluate R-factor redistribution as the mechanism of its survival benefit.

OBJECTIVE

We retrospectively evaluated surgical resections for lung cancer in the population-based observational 'Mid-South Quality of Surgical Resection' cohort from 2009-2019, including a full-cohort and propensity-score matched analysis.

RESULTS

Of 3,505 resections, 34% were R0, 60% R-uncertain, and 6% R1 or R2. The R0 percentage increased from 9% in 2009 to 56% in 2019 (p < 0.0001). Kit cases were 66% R0 and 29% R-uncertain, compared to 14% R0 and 79% R-uncertain in non-kit cases (p < 0.0001). Compared with non-kit resections, kit resections had 12.3 times the adjusted odds of R0 versus R-uncertainty.Of 2,100 R-uncertain resections, kit cases had lower percentages of non-examination of lymph nodes, 1% vs. 14% (p < 0.0001) and non-examination of mediastinal lymph nodes, 8% vs. 35% (p < 0.0001). With the kit, more R-uncertain cases had examination of stations 7 (43% vs. 22%, p < 0.0001) and 10 (67% vs. 45%, p < 0.0001).The adjusted hazard ratio (aHR) for kit cases versus non-kit cases was 0.75 (confidence interval [CI]: 0.66-0.85, p < 0.0001). In 2,100 subjects with R-uncertain resections, kit cases had an aHR of 0.79 versus non-kit cases ([CI: 0.64-0.99], p=0.0384); however, in the 1,199 R0 resections the survival difference was not significant (aHR: 0.85[0.68-1.07], p = 0.17).

CONCLUSIONS AND RELEVANCE

A lymph node kit increased overall survival by increasing R0, reducing the probability of R-uncertain resections, and diminishing extreme R-uncertainty.

Lymphadenectomy in pulmonary metastasectomy

Lymph node (LN) removal during pulmonary metastasectomy is a prerequisite to achieve complete resection or at least collect prognostic information, but is not yet generally accepted. On average, the rate of unexpected lymph node involvement (LNI) is less than 10% in sarcoma, 20% in colorectal cancer (CRC) and 30% in renal cell carcinoma (RCC) when radical LN dissection is performed. LNI is a negative prognostic factor and presence of preoperative mediastinal disease usually leads to exclusion of the patient from metastasis surgery. Nonetheless, some authors found excellent prognoses even with mediastinal LNI in colorectal and RCC metastases when radical LN dissection was performed (median survival of 37 and 36 months, respectively). Multiple metastases, central location of the lesion followed by anatomical resections are associated with a higher LNI rate. The real prognostic influence of systematic LN dissection remains unclear. Two positive effects were described after radical lymphadenectomy: a trend for improved survival in RCC patients and a reduction of mediastinal recurrences from 23% to 0% in CRC patients. Unfortunately, there is a great number of studies that do not demonstrate any positive effect of lymphadenectomy during pulmonary metastasectomy except a pseudo stage migration effect. Future studies should not only focus on survival, but also on local and LN recurrence.

The significance of systematic lymph node dissection in surgery for early-stage non-small cell lung cancer patients aged ≤40 years

Background

Surgery remains the best option for treating early-stage non-small cell lung cancer (NSCLC), and lymph node dissection (LND) is an important step in this approach. However, the extent of LND in the general age population, especially in young patients, is controversial. This retrospective study aimed to investigate the correlation between systematic lymph node dissection (SLND) and prognosis in young (≤40 years) patients with stage IA NSCLC.

Methods

Clinicopathological data of 191 patients aged ≤40 years who underwent surgical pulmonary resection for stage IA NSCLC between January 2010 and December 2016 were retrospectively collected. Of the patients, 104 received SLND (SLND group), while the other 87 patients underwent sampling or no LND (non-SLND group). The disease-free survival (DFS) and overall survival (OS) curves of the patients from each group were plotted using the Kaplan-Meier method, and the correlations of the patients' clinical factors with prognosis were also analyzed.

Results

The median follow-up period was 55 months. During follow-up, 7 patients died, and recurrence or metastasis was detected in 16 patients. Kaplan-Meier analysis revealed no difference in DFS (P=0.132) between the SLND and non-SLND group, but a significant difference was found between the groups in OS (P=0.022). Additionally, there was no statistically pronounced difference in OS or DFS between male and female patients. Multivariate survival analysis showed that the type of SLND, as well as tumor size, is an independent prognostic factor for DFS (HR, 3.530; 95% CI, 1.120-11.119; P=0.031) and OS (HR, 13.076; 95% CI, 1.209-141.443; P=0.034).

Conclusions

For young (age ≤40) stage IA NSCLC patients with pathological invasive adenocarcinoma, intraoperative SLND can improve the DFS and OS. Further studies are needed to verify the most optimal degree of LND in young patients.

Finding the "True" N0 Cohort: Technical Aspects of Near-infrared Sentinel Lymph Node Mapping in Non-small Cell Lung Cancer

OBJECTIVE

To examine technical-, patient-, tumor-, and treatment-related factors associated with NIR guided SLN identification.

BACKGROUND

Missed nodal disease correlates with recurrence in early stage NSCLC. NIR-guided SLN mapping may improve staging and outcomes through identification of occult nodal disease.

METHODS

Retrospective analysis of 2 phase I clinical trials investigating NIR-guided SLN mapping utilizing ICG in patients with surgically resectable NSCLC.

RESULTS

In total, 66 patients underwent NIR-guided SLN mapping and lymphadenectomy after peritumoral ICG injection. There was significantly increased likelihood of SLN identification with injection dose ≥1 mg compared to <1 mg (65.2% vs 35.0%, P = 0.05), lung ventilation after injection (65.2% vs 35.0%, P = 0.05), and albumin dissolvent (68.1%) compared to fresh frozen plasma (28.6%) and sterile water (20.0%) (P = 0.01). In patients receiving the optimized ICG injection, there was significantly increased likelihood of SLN identification with radiologically solid nodules compared to sub-solid nodules (77.4% vs 33.3%, P = 0.04) and anatomic resection compared to wedge resection (88.2% vs 52.2%, P = 0.04). Disease-free and overall survival are 100% in those with a histologically negative SLN identified (n = 25) compared to 73.6% (P = 0.02) and 63.6% (P = 0.01) in patients with node negative NSCLC established via routine lymphadenectomy alone (n = 22).

CONCLUSIONS

SLN(s) are more reliably identified with ICG dose ≥1 mg, albumin dissolvent, post-injection lung ventilation, radiologically solid nodules, and anatomic resections. To date, N0 status when established via NIR SLN mapping seems to be associated with decreased recurrence and improved survival after surgery for NSCLC.

Impact of histological components on selecting limited lymphadenectomy for lung adenocarcinoma ≤ 2 cm

OBJECTIVES

There is still some dispute regarding the performance of limited mediastinal lymphadenectomy (LML) even for lung adenocarcinoma ≤ 2 cm. We aimed to recognize the potential candidates who can benefit from LML based on the percentage of histological components (PHC).

METHODS

We analyzed 1160 surgical patients with invasive lung adenocarcinoma ≤ 2 cm from seven institutions between January 2012 and December 2015. All histological subtypes were listed in 5% increments by pathological slices. To test the accuracy of frozen section in judging PHC, frozen section slides from 140 cases were reviewed by three pathologists.

RESULTS

There were 882 patients with systematic mediastinal lymphadenectomy (SML) and 278 with LML. Multivariable analysis indicated that, the total percentage of micropapillary and solid components (PHC_MIP+S) > 5 % was the independent predictor of N2 metastasis (P < 0.001). Overall, recurrence-free survival (RFS) and overall survival (OS) favored SML compared with LML, but the subgroup analysis revealed LML and SML had similar prognosis in the group of PHC_MIP+S ≤ 5 %. Moreover, multivariable Cox analysis showed LML (vs. SML) was independently associated with worse prognosis for patients with PHC_MIP+S > 5 % (RFS, HR = 2.143, P < 0.001; OS, HR=1.963, P < 0.001), but not for those with PHC_MIP+S ≤ 5 % (RFS, P = 0.398; OS, P = 0.298). The sensitivity and specificity of frozen section to intraoperatively identify PHC_MIP+S ≤ 5 % were 97.6 % and 84.2 %, respectively.

CONCLUSIONS

PHC_MIP+S showed the predictive value for N2 metastasis and procedure-specific outcome (LML vs. SML). It may serve as a feasible indicator for identifying proper candidates of LML by using intraoperative frozen section.

Percutaneous lung microwave ablation versus lung resection in high-risk patients. A monocentric experience

Background and aim of work:

Lung microwave ablation (MWA) is considered an alternative treatment in high-risk patients, not suitable for surgery. The aim of our study is to compare MWA and pulmonary lobectomy in high-risk, lung cancer patients.

Methods:

This was a single-center, propensity score-weighted cohort study. All adult patients who underwent CT guided MWA for stage I NSCLC between June 2009-October 2014 were included in the study and were compared with a cohort of patients submitted to lung lobectomy in the same period of time. Outcomes were overall survival (OS) and disease-free survival (DFS).

Results:

32 patients underwent MWA, and 35 high-risk patients submitted to lung lobectomy in the same period were selected. Median follow-up time was 51.1 months (95% CI: 43.8-62.3). Overall survival was 43.8 (95% CI: 26.1-55) and 55.8 months (95% CI: 49.9-76.8) in the MWA group and Lobectomy group, respectively. Negative prognostic factors were MWA procedure (HR:2.25, 95% CI: 1.20-4.21, p= 0.0109) and nodule diameter (HR: 1.04, 95% CI: 1.01-1.07; p= 0.007) for OS, while MWA procedure (HR: 5.2; 95% CI: 2.1-12.8: p < 0.001), ECOG 3 (HR: 5.0; 95% CI: 1.6-15.6; p = 0.006) and nodule diameter (HR: 1.1; 95% CI: 1.0-1.1; p = 0.003) for DFS.

Conclusions:

Our study demonstrated a high percentage of local relapse in the MWA group but a comparable overall survival. Although lung lobectomy remains the gold standard treatment for stage I NSCLC, we can consider the MWA procedure as valid alternative local treatment in high-risk patients for stage I NSCLC. (www.actabiomedica.it)

Locally advanced non-small cell lung cancer: the place of specialist thoracic surgery in the multidisciplinary team

One reason that lung cancer is the leading cause of cancer mortality worldwide, is that surgical intervention is highly dependent on earlier tumor stage and good patient condition. As large proportion of cases are already metastatic at presentation and many are locally advanced, curative surgery is only possible in a minority of fit patients. Increasing the number of patients achieving complete resection is one of the avenues to increase overall survival using our existing technology. In the past, complex cases may have been sporadically discussed between various specialists in order to achieve better outcomes. More recently, the idea of discussing those cases on a routine basis, rather than an accident of geography or referral pattern, gave rise to the multidisciplinary team. Lung cancer management is now increasingly complex, especially with novel modalities such as targeted therapies, immune checkpoint inhibitors and stereotactic body radiotherapy delivery. Likewise, in thoracic surgery, minimally invasive techniques, early recovery after surgery protocols and complex techniques for resecting locally advanced tumours or preserving lung parenchyma must all be deployed appropriately to continue our incremental gains in survival and quality of life. To highlight the role of specialist thoracic surgeon in the multidisciplinary care of locally advanced non-small cell lung cancer, we conducted a search of English language publications for its multidisciplinary-based surgical management. We limited our search to the last decade, then hand-searched relevant references. In addition, we used our large prospective database as a team-oriented specialized thoracic surgical service to benchmark and demonstrate the benefits of specialist surgeons in the modern multidisciplinary team. In conclusion, patients with locally advanced non-small cell lung cancer should have any surgical option withheld without a specialist thoracic surgical opinion as part of the multidisciplinary team discussion.

Survival After Mediastinal Node Dissection, Systematic Sampling, or Neither for Early Stage NSCLC

INTRODUCTION

The American College of Surgeons Oncology Group Z0030 found no survival difference between patients with early stage NSCLC who had mediastinal nodal dissection or systematic sampling. However, a meta-analysis of 1980 patients in five randomized controlled trials from 1989 to 2007 associated better survival with nodal dissection. We tested the survival impact of the extent of nodal dissection in curative-intent resections for early stage NSCLC in a population-based observational cohort.

METHODS

Resections for clinical T1 or T2, N0 or nonhilar N1, M0 NSCLC in four contiguous United States Hospital Referral Regions from 2009 to 2019 were categorized into mediastinal nodal dissection, systematic sampling, and "neither" on the basis of of the evaluation of lymph node stations. We compared demographic and clinical characteristics, perioperative complication rates, and survival after assessing statistical interactions and confounding.

RESULTS

Of the 1942 eligible patients, 18% had nodal dissection, 6% had systematic sampling, and 75% had an intraoperative nodal evaluation that met neither standard. In teaching hospitals, nodal dissection was associated with a lower hazard of death than "neither" resections (0.57 [95% confidence interval: 0.41-0.79]) but not systematic sampling (0.74 [0.40-1.37]) after adjusting for multiple comparisons. There was no significant difference in hazard ratios at nonteaching institutions (p > 0.3 for all comparisons). Perioperative complication rates were not significantly worse after mediastinal nodal dissection or systematic sampling, compared with "neither," (p > 0.1 for all comparisons).

CONCLUSIONS

In teaching institutions, mediastinal nodal dissection was associated with superior survival over less-comprehensive pathologic nodal staging. There was no survival difference between teaching and nonteaching institutions, a finding that warrants further investigation.

Minimizing residual occult nodal metastasis in NSCLC: recent advances, current status and controversies

Introduction: Nodal involvement in lung cancer is a significant determinant of prognosis and treatment management. New evidence exists regarding the management of occult lymph node metastasis and residual disease in the fields of imaging, mediastinal staging, and operative management.Areas covered: This review summarizes the latest body of knowledge on the identification and management of occult lymph node metastasis in NSCLC. We focus on tumor-specific characteristics; imaging modalities; invasive mediastinal staging; and operative management including, technique, degree of resection, and lymph node examination.Expert opinion: Newly identified risk-factors associated with nodal metastasis including tumor histology, location, radiologic features, and metabolic activity are not included in professional societal guidelines due to the heterogeneity of their reporting and uncertainty on how to adopt them into practice. Imaging as a sole diagnostic method is limited. We recommend confirmation with invasive mediastinal staging. EBUS-FNA is the best initial method, but adoption has not been uniform. The diagnostic algorithm is less certain for re-staging of mediastinal nodes after neoadjuvant therapy. Mediastinal node sampling during lobectomy remains the gold-standard, but evidence supports the use of minimally invasive techniques. More study is warranted regarding sublobar resection. No consensus exists regarding lymph node examination, but new evidence supports reexamination of current quality metrics.

Beyond Margin Status: Population-Based Validation of the Proposed International Association for the Study of Lung Cancer Residual Tumor Classification Recategorization

INTRODUCTION

The International Association for the Study of Lung Cancer's (IASLC's) proposal to recategorize the residual tumor (R) classification for resected NSCLC needs validation.

METHODS

Using a 2009 to 2019 population-based multi-institutional NSCLC resection cohort from the United States, we classified resections by Union for International Cancer Control (UICC) and IASLC R criteria and compared the distribution of R classification variables and their survival associations.

RESULTS

Of 3361 resections, 95.3% were R0, 4.3% were R1, and 0.4% were R2 by UICC criteria; 33.3% were R0, 60.8% were R-uncertain, and 5.8% were R1/2 by IASLC criteria; 2044 patients (63.8%) migrated from UICC R0 to IASLC R-uncertain. Median survival was not reached, 69 (95% confidence interval [CI]: 64-77), and 25 (95% CI: 18-36) months, respectively, for patients with IASLC R0, R-uncertain, and R1 or R2 resections. Failure to achieve nodal dissection criteria caused 98% of migration to R-uncertainty, metastasis to the highest mediastinal node station, 5.8%. Compared with R0, R-uncertain resections with mediastinal nodes, no mediastinal nodes, and no nodes had adjusted hazard ratios of 1.28 (95% CI: 1.10-1.48), 1.47 (95% CI: 1.24-1.74), and 1.74 (95% CI: 1.37-2.21), respectively, suggesting a dose-response relationship between nodal R-uncertainty and survival. Accounting for mediastinal nodal involvement, the highest mediastinal station involvement was not independently prognostic. The incomplete resection variables were uniformly prognostic.

CONCLUSIONS

The proposed R classification recategorization variables were mostly prognostic, except the highest mediastinal nodal station involvement. Further categorization of R-uncertainty by severity of nodal quality deficit should be considered.

Prognostic relevance of regional lymph-node distribution in patients with N1-positive non-small cell lung cancer: A retrospective single-center analysis

OBJECTIVE

Lymph node (LN) metastases predict survival in patients with non-small cell lung cancer (NSCLC) treated with curative surgery. Nevertheless, prognostic differences within the same nodal (N) status have been reported. Consequently, the International Association for the Study of Lung Cancer (IASLC) proposed to stratify patients with limited nodal disease (pN1) from low (pN1a) to high (pN1b) nodal tumor burden. This study aimed to validate the IASLC proposal in a large single-center surgical cohort of patients with pN1 NSCLC.

MATERIAL AND METHODS

Data from 317 patients with pN1 NSCLC treated between January 2012 and December 2016, were retrospectively analyzed. Associations between distribution of LN metastases and survival were analyzed for different classification models-toward nodal extension (pN1a: one station involved; pN1b: multiple stations involved) and toward location (pN1 in the hilar [LN#10/11] or peripheral zone [LN#12-14]).

RESULTS

Tumor-specific survival (TSS) in the entire pN1 cohort was 67.1% at five years. Five-year TSS rates for pN1a and pN1b patients were comparable (67.6% vs. 66.5%, p = 0.623). Significant survival differences from pN1a to pN1b were observed only in patients with adenocarcinoma histology and completed adjuvant chemotherapy (5-year TSS: pN1a, 80.4% vs. pN1b, 49.6%; p = 0.005). TSS for LN metastases in the hilar zone/peripheral zone or in both zones was 68.2% and 59.9%, respectively (p = 0.068). In multivariate analysis, adjuvant chemotherapy, squamous cell histology, and nodal disease limited to one zone nodal disease were identified as independent beneficial prognostic factors (p < 0.05).

CONCLUSION

pN1 in only one region (hilar or lobar) was associated with better outcome than metastatic affection of both regions after surgery and adjuvant therapy. A stratification towards single (pN1a) and multiple (pN1b) N1-metastases was found of prognostic relevance only in adenocarcinoma. Prospective multicenter analysis of prognostic subgroups in N1 NSCLC is required to evaluate its clinical impact for consideration in future TNM classification.

Factors associated with nodal metastasis in 2-centimeter or less non-small cell lung cancer

OBJECTIVE

Lymph node involvement is an important determinant of treatment and prognosis in non-small cell lung cancer (NSCLC) and must be determined via surgical lymph node (LN) evaluation. However, lymphadenectomy is associated with multiple significant morbidities. Recent studies have suggested LN evaluation can be foregone in some or all patients with NSCLC ≤2.0 cm. Our objective was to identify whether these patients may be safely spared the morbidity of lymphadenectomy.

METHODS

We undertook a retrospective study of patients treated for NSCLC ≤2.0 cm at a single institution from 2005 to 2017. We examined patient, demographic, and tumor variables for associations with LN metastases via univariable and multivariable analyses.

RESULTS

In total, 555 patients met our inclusion criteria. Our primary independent variables included tumor size, histology, and histologic subtype. Although tumors ≤1 cm were less likely to have LN metastases than 1.1- to 2-cm tumors (6.8% vs 13.3%), there was no statistically significant difference. Histologic type was not associated with LN status. In an adenocarcinoma subgroup analysis, micropapillary predominant tumors were more likely to have LN metastases. All invasive mucinous adenocarcinomas and minimally invasive adenocarcinomas were N0.

CONCLUSIONS

LN evaluation may be unnecessary in patients with minimally invasive adenocarcinoma or invasive mucinous adenocarcinomas ≤2.0 cm. However, this information is rarely available pre- or intraoperatively. Thus, we recommend LN evaluation always be performed when possible, even for subcentimeter NSCLC, unless the histology is absolutely certain. To our knowledge, this is the largest dataset published to study patients with NSCLC ≤2.0 cm.

Safety of lymphadenectomy during video-assisted thoracic surgery lobectomy: analysis from a national database

OBJECTIVES

The Italian VATS Group database was accessed to evaluate whether preoperative and intraoperative factors may affect the safety of lymphadenectomy (LA) during video-assisted thoracic surgery lobectomy.

METHODS

All video-assisted thoracic surgery lobectomy procedures performed between 1 January 2014 and 30 March 2017 for non-small-cell lung cancer with cN0 or cN1 disease were identified in the database. LA safety was evaluated based on intraoperative (operative time, bleeding and conversion rate) and postoperative (30-day morbidity and mortality, chest drain duration and length of stay) outcomes and was correlated with the number of resected lymph nodes and the rates of nodal upstaging. Continuous variables were presented as mean ± standard deviation and compared using the unpaired t-test; the χ2 test was used for categorical variables. Univariable analysis was performed on selected variables. Significant variables (P < 0.30) were entered into a Cox multivariable logistic regression model, using the overall and specific occurrence of complications as dependent variables. The Spearman's rank correlation coefficient was applied as needed.

RESULTS

A total of 3181 cases (2077 men, 65.3%; mean age of 69 years) met the enrolment criteria. Final pathology was consistent with adenocarcinoma (n = 2262, 67.5%), squamous cell (n = 520, 15.5%), typical (n = 184, 5.5%) and atypical carcinoid (n = 48, 1.4%) and other (n = 335, 10%). The mean number of resected lymph nodes was 13.42 ± 8.24; nodal upstaging occurred in 308 of 3181 (9.68%) cases. Six hundred and fifty-five complications were recorded in 404 (12.7%) patients; in this series, no mortality was observed. Univariable and multivariable analyses did not show any association between the extension of LA and intraoperative or postoperative outcomes. The number of resected lymph nodes and nodal upstagings showed a minimal correlation with intraoperative outcomes and a moderate correlation with postoperative air leak (ρ = 0.35 and ρ = 0.48, respectively), arrhythmia (ρ = 0.29 and ρ = 0.35, respectively), chest drain duration (ρ = 0.35 and ρ = 0.51, respectively) and length of stay (ρ = 0.35).

CONCLUSIONS

Based on the VATS Group data, video-assisted thoracic surgery LA proved to be safe and displayed good outcomes even when performed with an extended approach.

Early-Stage NSCLC: Advances in Thoracic Oncology 2018

2018 was a banner year for all thoracic oncology, but especially for early-stage NSCLC. Three seminal events occurred in the approximately 18 months from mid-2017 to the end of 2018: in June 2017 at the American Society of Clinical Oncology Annual Meeting a small, relatively unheralded study from Max Diehn's group at Stanford University reported on the use of a novel "cancer personalized profiling by deep sequencing" circulating tumor-DNA technology to identify minimal residual disease in patients after curative-intent radiation or surgery for NSCLC; in April 2018 at the American Association for Cancer Research Annual Meeting, Drew Pardoll presented a small pilot study of 21 patients who had received two doses of preoperative nivolumab; in September 2018, at the 19th World Conference on Lung Cancer, Harry J. De Koning presented the long-awaited results of the Dutch-Belgian Lung Cancer Screening Trial (NELSON). These three seminal studies, along with others which are reviewed in this paper, promise to accelerate our progress towards a world in which lung cancer is identified early, more patients undergo curative-intent treatment that achieves the promised cure, and those at risk for failure after treatment are identified early, when the cancer remains most vulnerable. The day is around the corner when lung cancer is defanged and no longer the worldwide terror it currently is. We herein present an overview of the most recent body of work that moves us inexorably towards that day.