The Evolving Concept of Complete Resection in Lung Cancer Surgery

The International Association for the Study of Lung Cancer Lung Cancer Staging Project: Proposals for Revision of the Classification of Residual Tumor After Resection for the Forthcoming (Ninth) Edition of the TNM Classification of Lung Cancer

INTRODUCTION

The goal of surgical resection is to completely remove a cancer; it is useful to have a system to describe how well this was accomplished. This is captured by the residual tumor (R) classification, which is separate from the TNM classification that describes the anatomic extent of a cancer independent of treatment. The traditional R-classification designates as R0 a complete resection, as R1 a macroscopically complete resection but with microscopic tumor at the surgical margin, and as R2 a resection that leaves gross tumor behind. For lung cancer, an additional category encompasses situations in which the presence of residual tumor is uncertain.

METHODS

This paper represents a comprehensive review of evidence regarding these R categories and the descriptors thereof, focusing on studies published after the year 2000 and with adjustment for potential confounders.

RESULTS

Consistent discrimination between complete, uncertain, and incomplete resection is revealed with respect to overall survival. Evidence regarding specific descriptors is generally somewhat limited and only partially consistent; nevertheless, the data suggest retaining all descriptors but with clarifications to address ambiguities.

CONCLUSION

On the basis of this review, the R-classification for the ninth edition of stage classification of lung cancer is proposed to retain the same overall framework and descriptors, with more precise definitions of descriptors. These refinements should facilitate application and further research.

The International Association for the Study of Lung Cancer (IASLC) Staging Project for Lung Cancer: Recommendation to Introduce Spread Through Air Spaces as a Histologic Descriptor in the Ninth Edition of the TNM Classification of Lung Cancer. Analysis of 4061 Pathologic Stage I NSCLC

INTRODUCTION

Spread through air spaces (STAS) consists of lung cancer tumor cells that are identified beyond the edge of the main tumor in the surrounding alveolar parenchyma. It has been reported by meta-analyses to be an independent prognostic factor in the major histologic types of lung cancer, but its role in lung cancer staging is not established.

METHODS

To assess the clinical importance of STAS in lung cancer staging, we evaluated 4061 surgically resected pathologic stage I R0 NSCLC collected from around the world in the International Association for the Study of Lung Cancer database. We focused on whether STAS could be a useful additional histologic descriptor to supplement the existing ones of visceral pleural invasion (VPI) and lymphovascular invasion (LVI).

RESULTS

STAS was found in 930 of 4061 of the pathologic stage I NSCLC (22.9%). Patients with tumors exhibiting STAS had a significantly worse recurrence-free and overall survival in both univariate and multivariable analyses involving cohorts consisting of all NSCLC, specific histologic types (adenocarcinoma and other NSCLC), and extent of resection (lobar and sublobar). Interestingly, STAS was independent of VPI in all of these analyses.

CONCLUSIONS

These data support our recommendation to include STAS as a histologic descriptor for the Ninth Edition of the TNM Classification of Lung Cancer. Hopefully, gathering these data in the coming years will facilitate a thorough analysis to better understand the relative impact of STAS, LVI, and VPI on lung cancer staging for the Tenth Edition TNM Stage Classification.

Influencing Factors on the Quality of Lymph Node Dissection for Stage IA Non-Small Cell Lung Cancer: A Retrospective Nationwide Cohort Study

Lymphadenectomy is an essential part of complete surgical operation for non-small cell lung cancer (NSCLC). This retrospective, multicenter cohort study aimed to identify factors that influence the lymphadenectomy quality. Data were obtained from the Polish Lung Cancer Study Group Database. The primary endpoint was lobe-specific mediastinal lymph node dissection (L-SMLND). The study included 4271 patients who underwent VATS lobectomy for stage IA NSCLC, operated between 2007 and 2022. L-SMLND was performed in 1190 patients (27.9%). The remaining 3081 patients (72.1%) did not meet the L-SMLND criteria. Multivariate logistic regression analysis showed that patients with PET-CT (OR 3.238, 95% CI: 2.315 to 4.529; p < 0.001), with larger tumors (pT1a vs. pT1b vs. pT1c) (OR 1.292; 95% CI: 1.009 to 1.653; p = 0.042), and those operated on by experienced surgeons (OR 1.959, 95% CI: 1.432 to 2.679; p < 0.001) had a higher probability of undergoing L-SMLND. The quality of lymphadenectomy decreased over time (OR 0.647, 95% CI: 0.474 to 0.884; p = 0.006). An analysis of propensity-matched groups showed that more extensive lymph node dissection was not related to in-hospital mortality, complication rates, and hospitalization duration. Actions are needed to improve the quality of lymphadenectomy for NSCLC.

Predictors of Long-Term Survival of Thoracoscopic Lobectomy for Stage IA Non-Small Cell Lung Cancer: A Large Retrospective Cohort Study

The standard of care for patients with early-stage non-small cell lung cancer (NSCLC) is anatomical lung resection with lymphadenectomy. This multicenter, retrospective, cohort study aimed to identify predictors of 5-year survival in patients after thoracoscopic lobectomy for stage IA NSCLC. The study included 1249 patients who underwent thoracoscopic lobectomy for stage IA NSCLC between 17 April 2007, and December 28, 2016. The 5-year survival rate equaled 77.7%. In the multivariate analysis, higher age (OR, 1.025, 95% CI: 1.002 to 1.048; p = 0.032), male sex (OR, 1.410, 95% CI: 1.109 to 1.793; p = 0.005), chronic obstructive pulmonary disease (OR, 1.346, 95% CI: 1.005 to 1.803; p = 0.046), prolonged postoperative air leak (OR, 2.060, 95% CI: 1.424 to 2.980; p < 0.001) and higher pathological stage (OR, 1.271, 95% CI: 1.048 to 1.541; p = 0.015) were related to the increased risk of death within 5 years after surgery. Lobe-specific mediastinal lymph node dissection (OR, 0.725, 95% CI: 0.548 to 0.959; p = 0.024) was related to the decreased risk of death within 5 years after surgery. These findings provide valuable insights for clinical practice and may contribute to improving the quality of treatment of early-stage NSCLC.

Identification of Factors Related to the Quality of Lymphadenectomy for Lung Cancer: Secondary Analysis of Prospective Randomized Trial Data

The outcomes of non-small cell lung cancer surgery are influenced by the quality of lymphadenectomy. This study aimed to evaluate the impact of different energy devices on lymphadenectomy quality and identify additional influencing factors. This secondary analysis of the prospective randomized trial data (clinicaltrials.gov: NCT03125798) compared patients who underwent thoracoscopic lobectomy with the LigaSure device (study group, n = 96) and monopolar device (control group, n = 94). The primary endpoint was the lobe-specific mediastinal lymphadenectomy. Lobe-specific mediastinal lymphadenectomy criteria were met in 60.4% and 38.3% of patients in the study and control groups, respectively (p = 0.002). In addition, in the study group, the median number of mediastinal lymph node stations removed was higher (4 vs. 3, p = 0.017), and complete resection was more often achieved (91.7% vs. 80.9%, p = 0.030). Logistic regression analysis indicated that lymphadenectomy quality was positively associated with the use of the LigaSure device (OR, 2.729; 95% CI, 1.446 to 5.152; p = 0.002) and female sex (OR, 2.012; 95% CI, 1.058 to 3.829; p = 0.033), but negatively associated with a higher Charlson Comorbidity Index (OR, 0.781; 95% CI, 0.620 to 0.986; p = 0.037), left lower lobectomy (OR, 0.263; 95% CI, 0.096 to 0.726; p = 0.010) and middle lobectomy (OR, 0.136; 95% CI, 0.031 to 0.606, p = 0.009). This study found that using the LigaSure device can improve the quality of lymphadenectomy in lung cancer patients and also identified other factors that affect the quality of lymphadenectomy. These findings contribute to improving lung cancer surgical treatment outcomes and provide valuable insights for clinical practice.

Comparison of the LigaSure™ bipolar vessel sealer to monopolar electrocoagulation for thoracoscopic lobectomy and lymphadenectomy: a prospective randomized controlled trial

BACKGROUND

High-energy devices allow better vessel sealing compared with monopolar electrocautery and could improve the outcomes of surgical operations. The objective of the study was to compare tissue dissection by the LigaSure™ device with that by monopolar electrocoagulation for thoracoscopic lobectomy and lymphadenectomy.

METHODS

This pragmatic, parallel group, prospective randomized controlled trial was funded by the Medtronic External Research Program (ISR-2016-10,756) and registered at www.

CLINICALTRIALS

gov (NCT03125798). The study included patients aged 18 years or older, who had undergone thoracoscopic lobectomy with lymphadenectomy at the Department of Thoracic Surgery of Poznan University of Medical Sciences between May 3, 2018, and November 4, 2021. Using simple randomization, the patients were assigned to undergo tissue dissection with either the LigaSure device (study group) or monopolar electrocautery (control group). Participants and care givers, except operating surgeons, were blinded to group assignment. The primary outcome was postoperative chest drainage volume. Secondary outcomes were change of the esophageal temperature during subcarinal lymphadenectomy and C-reactive protein level 72 h after surgery.

RESULTS

Study outcomes were analyzed in 107 patients in each group. We found no differences between the study and control groups in terms of chest drainage volume (550 vs. 600 mL, respectively; p = 0.315), changes in esophageal temperature (- 0.1 °C vs. - 0.1 °C, respectively; p = 0.784), and C-reactive protein levels (72.8 vs. 70.8 mg/L, respectively; p = 0.503). The mean numbers of lymph nodes removed were 12.9 (SD: 3.1; 95% CI, 12.4 to 13.5) in the study group and 11.6 (SD: 3.2; 95% CI, 11.0 to 12.2) in the control group (p < 0.001).

CONCLUSIONS

The use of the LigaSure device did not allow to decrease the chest drainage volume, local thermal spread, and systemic inflammatory response. The number of lymph nodes removed was higher in patients operated with the LigaSure device, which indicated better quality of lymphadenectomy.

Uncertain resection of highest mediastinal lymph node positive among pN2 non-small cell lung cancer patients: survival analysis of postoperative radiotherapy and driver gene mutations

BACKGROUND AND PURPOSE

The role of postoperative radiotherapy (PORT) in uncertain resection of pN2 non-small cell lung cancer (NSCLC) with highest mediastinal lymph node positive has not been determined. We aim to evaluate the effect of PORT and driver gene mutation status (DGMS) on survival in such patients.

METHODS

140 selected patients were grouped according to whether they received PORT and their DGMS. Locoregional recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), disease-free survival (DFS), and overall survival (OS) of each group were evaluated by Kaplan-Meier analyses. COX regression was used to evaluate the effects of various factors on DFS and OS.

RESULTS

Of 140 patients, thirty-four patients (24.3%) received PORT, and forty (28.6%) had positive driver gene mutation status (DGp). PORT significantly prolonged LRFS (p = 0.002), DFS (p = 0.019) and OS (p = 0.02), but not DMFS (p = 0.062). By subgroup analysis, in patients with negative driver gene mutation status (DGn), those receiving PORT had notably longer LRFS (p = 0.022) and DFS (p = 0.033), but not DMFS (p = 0.060) or OS (p = 0.215), compared to those not receiving PORT. Cox analysis showed that the number of positive lymph nodes (PLNs) and administration of PORT were independent prognostic factors of DFS, and pathology, PLNs, and DGMS may be prognostic factors of OS (all p < 0.05).

CONCLUSION

Postoperative radiotherapy may improve locoregional recurrence-free and disease-free survival in patients with pN2 NSCLC with positive highest mediastinal lymph nodes, while driver gene mutation status impacted OS significantly. Only patients with positive driver gene mutations experienced significant overall survival benefits from postoperative radiotherapy.

Perioperative Outcomes of Video-Assisted Thoracoscopic Surgery Versus Open Thoracotomy After Neoadjuvant Chemoimmunotherapy in Resectable NSCLC

Background

Neoadjuvant chemoimmunotherapy becomes more widespread in the treatment of NSCLC, but few studies have reported the details of surgical techniques and perioperative challenges following neoadjuvant chemoimmunotherapy until now. The primary aim of our study was to address the feasibility and safety of pulmonary resection after neoadjuvant chemoimmunotherapy via different surgical approaches, video-assisted thoracoscopic surgery (VATS) and open thoracotomy.

Methods

Patients with an initial diagnosis of clinical stage IB-IIIB(T3-4N2) NSCLC, who received neoadjuvant chemoimmunotherapy and surgery between January 2019 and August 2021 were included. Patients were retrospectively divided into two groups (VATS, and thoracotomy), and differences in perioperative, oncological, and survival outcomes were compared.

Results

In total, there were 131 NSCLC patients included. Surgery was delayed beyond 42 days in 21 patients (16.0%), and radical resection (R0) was achieved in 125 cases (95.4%). Lobectomy was the principal method of pulmonary resection (102 cases, 77.9%) and pneumonectomy was performed in 11 cases (8.4%). Postoperative complications within 30 days occurred in 28 patients (21.4%), and no 90-day mortality was recorded. There were 53 patients (38.5%) treated with VATS, and 78 (59.5%) with open thoracotomy. VATS could achieve similar definitive resection rates, postoperative recovery courses, comparable morbidities, and equivalent RFS rates(p>0.05), with the advantages of reduced operative time (160.1 ± 40.4 vs 177.7 ± 57.7 min, p=0.042), less intraoperative blood loss (149.8 ± 57.9 vs 321.2 ± 72.3 ml, p=0.021), and fewer intensive care unit(ICU) stays after surgery (3.8% vs 20.5%, p=0.006) compared with open thoracotomy. However, the mean number of total lymph nodes resected was lower in the VATS group (19.5 ± 7.9 vs 23.0 ± 8.1, p=0.013). More patients in the thoracotomy group received bronchial sleeve resection/bronchoplasty (53.8% vs 32.1%, p=0.014) and vascular sleeve resection/angioplasty (23.1% vs 3.8%, p=0.003). After propensity score matching (PSM) analysis, VATS still had the advantage of fewer ICU stays after surgery (2.3% vs. 20.5%, p=0.007).

Conclusions

Our results have confirmed that pulmonary resection following neoadjuvant PD-1 inhibitors plus chemotherapy is safe and feasible. VATS could achieve similar safety, definitive surgical resection, postoperative recovery, and equivalent oncological efficacy as open thoracotomy, with the advantage of fewer ICU stays after surgery.

A real-world comparison between neoadjuvant chemoimmunotherapy and chemotherapy alone for resectable non-small cell lung cancer

BACKGROUND

The impact of neoadjuvant chemoimmunotherapy on pulmonary resection and related outcomes had been poorly reported in previous studies. The present study aims to clarify the efficacy and safety of neoadjuvant chemoimmunotherapy, and intraoperative difficulty in the following surgery, in comparison with chemotherapy alone in non-small cell lung cancer (NSCLC).

METHODS

Patients with newly diagnosed clinical stages IB-IIIB(T3-4N2) NSCLC, received neoadjuvant chemotherapy + PD-1 inhibitors (PD-1 + Chemo group) or chemotherapy alone (Chemo group) followed by surgery between December 2018 and December 2020 were included. The clinicopathological characteristics were retrospectively reviewed and analyzed.

RESULTS

There were 69 NSCLC patients in the PD-1 + Chemo group and 121 in the Chemo group. The major pathological response (MPR) rate in the PD-1 + Chemo group was 49.3%, higher than that of 19.0% in the Chemo group (p < 0.001). The 2-year disease-free survival (DFS) rate was 79.3% and 60.2%, respectively, in the two groups (p = 0.048). Multivariate analysis identified surgical radicality (hazard ratio (HR), 2.954, 95% confidence interval (CI), 1.527-5.714, p = 0.001), and pathological response (MPR(CR) vs. SD(PD), HR, 0.248, 95% CI, 0.107-0.572, p = 0.001) to be independent prognostic factors for DFS. Lobectomy was performed in 73.9% and 66.1% of patients, respectively, and bronchial sleeve resection/bronchoplasty rate was also comparable (43.4% vs. 40.5%, p = 0.688). More patients in the PD-1 + Chemo group received vascular sleeve resection/angioplasty (15.9% vs. 6.6%, p = 0.039) and pericardial resection (10.1% vs. 2.5%, p = 0.038). After propensity score matching analysis, pericardial resection rate was still slightly higher in the PD-1 + Chemo group (9.4% vs. 1.6%, p = 0.05). Perioperative morbidities within 30 days and mortality in 90 days were comparable between groups (p > 0.05).

CONCLUSIONS

Neoadjuvant chemoimmunotherapy for NSCLC is safe and feasible, with higher MPR rates, as well as favorable DFS than chemotherapy alone. Surgical complexity might be increased in certain patients, with comparable perioperative morbidity and mortality.