Temporal trends in outcomes following sublobar and lobar resections for small (≤2 cm) non–small cell lung cancers—a Surveillance Epidemiology End Results database analysis

Lobar or sublobar resection of peripheral stage I non-small cell lung cancer

PURPOSE OF REVIEW

We aim to highlight two recent clinical trials that have altered the approach of the management of stage I nonsmall cell lung cancer.

RECENT FINDINGS

The JCOG 0802 and CALGB 140503 trials demonstrated that sublobar resection is noninferior to lobectomy for overall and disease-free survival in patients with stage I nonsmall cell lung cancer.

SUMMARY

Since 1962, lobectomy has been deemed the gold standard treatment for operable lung cancer. However, two recent clinical trials have demonstrated that, for select patients, sublobar resection is oncologically noninferior; results, which are leading us into a new era for the surgical management of lung cancer. Notwithstanding the progress made by these studies and the opportunities that have been put forth, questions remain. This review aims at reviewing the results of both trials and to discuss future perspectives for the surgical treatment of lung cancer.

Survival outcomes of segmentectomy and lobectomy for early stage non-small cell lung cancer: a systematic review and meta-analysis

BACKGROUND

The question of whether segmentectomy and lobectomy have similar survival outcomes for patients with early-stage non-small cell lung cancer (NSCLC) is a matter of debate.

METHODS

A cohort study and randomized controlled trial were included, comparing segmentectomy and lobectomy, by utilizing computerized access to the Pubmed, Web of Science, and Cochrane Library databases up until July 2022. The Cochrane Collaboration tool was used to evaluate the randomized controlled trials, while the Newcastle-Ottawa Scale (NOS) was used to evaluate the cohort studies. Sensitivity analyses were also carried out.

RESULTS

The analysis incorporated 17 literature studies, including one randomized controlled trial and 16 cohort studies, and was divided into a segmentectomy group (n = 2081) and a lobectomy group (n = 2395) based on the type of surgery the patient underwent. Each study was followed up from 27 months to 130.8 months after surgery. Over survival (OS): HR = 1.14, 95%CI(0.97,1.32), P = 0.10; disease-free survival (DFS): HR = 1.13, 95%CI(0.91,1.41), P = 0.27; recurrence-free survival (RFS): HR = 0.95, 95%CI(0.81,1.12), P = 0.54.

CONCLUSION

The results of the study suggest that the survival outcomes of the segmentectomy group were not inferior to that of the lobectomy group. Segmentectomy should therefore be considered as a treatment option for early stage NSCLC.

Resectable non-stage IV nonsmall cell lung cancer: the surgical perspective

Surgery remains an essential element of the multimodality radical treatment of patients with early-stage nonsmall cell lung cancer. In addition, thoracic surgery is one of the key specialties involved in the lung cancer tumour board. The importance of the surgeon in the setting of a multidisciplinary panel is ever-increasing in light of the crucial concept of resectability, which is at the base of patient selection for neoadjuvant/adjuvant treatments within trials and in real-world practice. This review covers some of the topics which are relevant in the daily practice of a thoracic oncological surgeon and should also be known by the nonsurgical members of the tumour board. It covers the following topics: the pre-operative selection of the surgical candidate in terms of fitness in light of the ever-improving nonsurgical treatment alternatives unfit patients may benefit from; the definition of resectability, which is so important to include patients into trials and to select the most appropriate radical treatment; the impact of surgical access and surgical extension with the evolving role of minimally invasive surgery, sublobar resections and parenchymal-sparing sleeve resections to avoid pneumonectomy.

Effect of segmental versus lobectomy in minimally invasive surgery on postoperative wound complications in lung cancer patients: A meta-analysis

It is still a matter of debate whether the surgical segmentectomy and lobectomy of lung cancer are comparable in the incidence of perioperative wound complications. An extensive review of the literature through August 2023 was carried out with a critical review of four databases. Following the acceptance and elimination criteria set out in the trial, as well as a qualitative assessment of the literature, this resulted in a review of related research that compared the results of both lobectomy and partial resection in the management of lung cancer. The analysis of the data was performed with the RevMan 5.3 software, and the 95% confidence interval [CI] and odds ratio [OR] were performed with either stationary or random-effect models. It is concluded that the operation time of lobectomy is shorter than that of sectioning in the treatment of segmentectomy (mean difference [MD], -38.62; 95% CI, -41.96, -35.28; p < 0.0001). But the rate of postoperative wound infection (OR, 0.62; 95% CI, 0.18, 2.15; p = 0.45) and intraoperative blood loss (MD, 17.54; 95% CI, -4.19, 39.26; p = 0.11) were not significantly different for them. Thus, for those who have received a pulmonary carcinoma operation, different operative methods might not have an impact on the incidence of postoperative wound infections. The operative procedure appears to have a major impact on the length of the operation in patients.

PB-LNet: a model for predicting pathological subtypes of pulmonary nodules on CT images

OBJECTIVE

To investigate the correlation between CT imaging features and pathological subtypes of pulmonary nodules and construct a prediction model using deep learning.

METHODS

We collected information of patients with pulmonary nodules treated by surgery and the reference standard for diagnosis was post-operative pathology. After using elastic distortion for data augmentation, the CT images were divided into a training set, a validation set and a test set in a ratio of 6:2:2. We used PB-LNet to analyze the nodules in pre-operative CT and predict their pathological subtypes. Accuracy was used as the model evaluation index and Class Activation Map was applied to interpreting the results. Comparative experiments with other models were carried out to achieve the best results. Finally, images from the test set without data augmentation were analyzed to judge the clinical utility.

RESULTS

Four hundred seventy-seven patients were included and the nodules were divided into six groups: benign lesions, precursor glandular lesions, minimally invasive adenocarcinoma, invasive adenocarcinoma Grade 1, Grade 2 and Grade 3. The accuracy of the test set was 0.84. Class Activation Map confirmed that PB-LNet classified the nodules mainly based on the lungs in CT images, which is in line with the actual situation in clinical practice. In comparative experiments, PB-LNet obtained the highest accuracy. Finally, 96 images from the test set without data augmentation were analyzed and the accuracy was 0.89.

CONCLUSIONS

In classifying CT images of lung nodules into six categories based on pathological subtypes, PB-LNet demonstrates satisfactory accuracy without the need of delineating nodules, while the results are interpretable. A high level of accuracy was also obtained when validating on real data, therefore demonstrates its usefulness in clinical practice.

Is wedge a dirty word? Demographic and facility-level variables associated with high-quality wedge resection

Objectives

Although sublobar resections have gained traction, wedge resections vary widely in quality. We seek to characterize the demographic and facility-level variables associated with high-quality wedge resections.

Methods

The National Cancer Database was queried from 2010 to 2018. Patients with T1/T2 N0 M0 non-small cell lung cancer 2 cm or less who underwent wedge resection without neoadjuvant therapy were included. A wedge resection with no nodes sampled or with positive margins was categorized as a low-quality wedge. A wedge resection with 4 or more nodes sampled and negative margins was categorized as a high-quality wedge. Facility-specific variables were investigated via quartile analysis based on the overall volume and proportion of high-quality wedge or low-quality wedge resections performed.

Results

A total of 21,742 patients met inclusion criteria, 6390 (29.4%) of whom received a high-quality wedge resection. Factors associated with high-quality wedge resection included treatment at an academic center (3005 [47.0%] vs low-quality wedge 6279 [40.9%]; P < .001). The 30- and 90-day survivals were similar, but patients who received a high-quality wedge resection had improved 5-year survival (4902 [76.7%] vs 10,548 [68.7%]; P < .001). Facilities in the top quartile by volume of high-quality wedge resections performed 69% (4409) of all high-quality wedge resections, and facilities in the top quartile for low-quality wedge resections performed 67.6% (10,378) of all low-quality wedge resections. A total of 113 facilities were in the top quartile by volume for both high-quality wedge and low-quality wedge resections.

Conclusions

High-quality wedge resections are associated with improved 5-year survival when compared with low-quality wedge resections. By volume, high-quality wedge and low-quality wedge resections cluster to a minority of facilities, many of which overlap. There is discordance between best practice guidelines and current practice patterns that warrants additional study.

The Role of Sublobar Resection for the Surgical Treatment of Non-Small Cell Lung Cancer

Lung cancer is the most common cancer killer in the world. The standard of care for surgical treatment of non-small cell lung cancer has been lobectomy. Recent studies have identified that sublobar resection has non-inferior survival rates compared to lobectomy, however. Sublobar resection may increase the number of patients who can tolerate surgery and reduce postoperative pulmonary decline. Sublobar resection appears to have equivalent results to surgery in patients with small, peripheral tumors and no lymph node disease. As the utilization of segmentectomy increases, there may be some centers that perform this operation more than other centers. Care must be taken to ensure that all patients have access to this modality. Future investigations should focus on examining the outcomes from segmentectomy as it is applied more widely. When employed on a broad scale, morbidity and survival rates should be monitored. As segmentectomy is performed more frequently, patients may experience improved postoperative quality of life while maintaining the same oncologic benefit.

Sub-Lobar Resection: The New Standard of Care for Early-Stage Lung Cancer

The Lung Cancer Study Group previously established lobectomy as the standard of care for treatment of clinical T1N0 NSCLC. Advances in imaging technology and refinements in staging have prompted a re-investigation to determine the non-inferiority of sub-lobar resections to lobectomies. Two recent randomized studies, JCOG 0802 and CALGB 140503, are reviewed here in the context of LCSG 0821. The studies confirm non-inferiority for sub-lobar resection (wedge or segmentectomy) compared to lobectomy for peripheral T1N0 NSCLC less than or equal to 2 cm. Sub-lobar resection should therefore be considered the new standard of care in this sub-set of patients with NSCLC.

Lobar or Sublobar Resection for Peripheral Stage IA Non-Small-Cell Lung Cancer

BACKGROUND

The increased detection of small-sized peripheral non-small-cell lung cancer (NSCLC) has renewed interest in sublobar resection in lieu of lobectomy.

METHODS

We conducted a multicenter, noninferiority, phase 3 trial in which patients with NSCLC clinically staged as T1aN0 (tumor size, ≤2 cm) were randomly assigned to undergo sublobar resection or lobar resection after intraoperative confirmation of node-negative disease. The primary end point was disease-free survival, defined as the time between randomization and disease recurrence or death from any cause. Secondary end points were overall survival, locoregional and systemic recurrence, and pulmonary functions.

RESULTS

From June 2007 through March 2017, a total of 697 patients were assigned to undergo sublobar resection (340 patients) or lobar resection (357 patients). After a median follow-up of 7 years, sublobar resection was noninferior to lobar resection for disease-free survival (hazard ratio for disease recurrence or death, 1.01; 90% confidence interval [CI], 0.83 to 1.24). In addition, overall survival after sublobar resection was similar to that after lobar resection (hazard ratio for death, 0.95; 95% CI, 0.72 to 1.26). The 5-year disease-free survival was 63.6% (95% CI, 57.9 to 68.8) after sublobar resection and 64.1% (95% CI, 58.5 to 69.0) after lobar resection. The 5-year overall survival was 80.3% (95% CI, 75.5 to 84.3) after sublobar resection and 78.9% (95% CI, 74.1 to 82.9) after lobar resection. No substantial difference was seen between the two groups in the incidence of locoregional or distant recurrence. At 6 months postoperatively, a between-group difference of 2 percentage points was measured in the median percentage of predicted forced expiratory volume in 1 second, favoring the sublobar-resection group.

CONCLUSIONS

In patients with peripheral NSCLC with a tumor size of 2 cm or less and pathologically confirmed node-negative disease in the hilar and mediastinal lymph nodes, sublobar resection was not inferior to lobectomy with respect to disease-free survival. Overall survival was similar with the two procedures. (Funded by the National Cancer Institute and others; CALGB 140503 ClinicalTrials.gov number, NCT00499330.).

Sublobar Resections

Sublobar resections are commonly performed operations that have seen an increase in applicability. The sublobar approach, comprising segmentectomy and wedge resections, can provide lung preservation and thus is better tolerated in select patients in comparison to lobectomy. These operations are offered for a variety of benign and malignant lesions. Understanding the indications and technical aspects of these approaches is paramount as improvements in lung cancer screening protocols and the imaging modalities has led to an increase in the detection of early-stage cancer. In this article, we discuss the anatomy, indications, technical approaches, and outcomes for sublobar resection.

A cross-sectional study: analysis of anatomical variation in the right upper lung intersegmental vein V2a based on a 3D reconstruction technique

BACKGROUND

This study aimed to summarize and analyze the anatomical structures of the right upper lung intersegmental vein V2a based on 3-dimensional (3D) reconstruction technology.

METHODS

We collected the enhanced computed tomography (CT) scans of 157 patients with pulmonary diseases, and reconstructed the right upper lung tissue structure through interactive qualitative and quantitative analysis (IQQA). According to the reconstruction results, the V2a of the right upper pulmonary intersegmental vein was returned to different veins for classification, and the subtypes were further subdivided according to the different vascular routes and the location of the pulmonary segmental bronchus.

RESULTS

Among 157 patients, there were 4 types of V2a according to the anatomical position of the veins. In type B (15 cases, 9.6%), V2a returned to the apical vein V1. In type C (2 cases, 1.3%), V2a did not exist, while in type D (1 case, 0.6%), V2a directly flowed into the right atrium. Type A is further divided into three subtypes (A1, A2, A3) according to the type of veins returned and the anatomical location of their confluence. In subtype A1 (110/139 cases, 79.1%), V2a returned to the posterior segment central vein. In subtype A2 (8/139 cases, 5.8%), V2a flowed from the B2 mediastinal surface down to the interlobular part of the posterior segmental vein. In subtype A3 (21/139 cases, 15.1%), V2a flowed between B1a and B2a and back to the central vein at the junction of the B2 and B3 bronchus. Type B is further divided into 3 subtypes (B1, B2, B3) according to the location of the apical posterior segmental bronchus. In B1 subtype (1/15 cases, 6.7%), V2a continued from the mediastinal surface of B1 back down to V1. In B2 subtype (7/15 cases, 46.7%), V2a continued from the medial side of the B1 lung back down to V1. In subtype B3 (7/15 cases, 46.7%), V2a flowed back into the central part of the posterior segmental vein.

CONCLUSIONS

This study, supported by 3D reconstruction technology, preliminarily summarized the V2a typology and further refined the anatomical differences of each subtype.

Development and validation of nomograms based on clinical characteristics and CT reports for the preoperative prediction of precise lymph node dissection in lung cancer

OBJECTIVE

To develop and validate nomograms for preoperative prediction of precision lymph node (LN) dissection in lung cancer.

PATIENTS AND METHODS

The prediction models of each group LNs (LNx) were developed in a primary cohort that consisted of 1380 patients with clinicopathologically confirmed lung cancer. Clinical characteristics and CT reports were extracted. Patients with LNx dissection were divided into training cohort and testing cohort. Nomograms were built through univariate and multivariate regression analysis in the training cohort and internally verified in the testing cohort. The accuracy of the models was verified by constructing survival analysis in patients without LNx dissection.

RESULTS

Due to the lack of sufficient patients for LN1, 8, 13, a total of 10 nomograms were constructed in this study, including LN-2 ∼ 7, 9 ∼ 12. According to the nomogram of each group LN, the most common independent risk factors predicting LN status were CT-reported lymphadenectasis, tumor diameter and location, and the others include age, gender, and whether there were multiple nodules, etc. All models showed good discrimination, with the average C-index of 0.738 in the training cohort and 0.707 in the testing cohort. Survival analysis in patients without LNx dissection all showed the high accuracy of each nomogram to predict LN metastasis status and TNM staging.

CONCLUSION

We constructed nomograms to predict the metastasis status of each group of lymph nodes based on clinical characteristics and CT reports. Surgeons can accurately determine the extent of lymph node dissection in patients with lung cancer based on our nomogram models before surgery.

Prognostic impact of the tumor volume doubling time in clinical T1 non-small cell lung cancer with solid radiological findings

BACKGROUND

The purpose of this study was to investigate better radiological prognostic factors in clinical T1 pure-solid non-small cell lung cancer (NSCLC).

METHODS

This study enrolled 284 patients with clinical T1 solid NSCLC who underwent anatomical lung resection. The Cox proportional hazard model was used to evaluate the prognostic impact of tumor volume doubling time (VDT) at disease-free survival (DFS) and cancer-specific survival (CSS).

RESULTS

The median VDT was 347 days. Age (hazard ratio (HR) = 1.04; 95% confidence interval (CI), 1.01-1.07) and standardized uptake value max (SUVmax) (>6.0) (HR = 2.61; 95% CI, 1.52-4.66) were identified as significantly independent worse prognostic factors for DFS in a multivariable analysis without VDT. Furthermore, a multivariable analysis without SUVmax identified age (HR = 1.06; 95% CI, 1.03-1.09), CEA (>5.0 ng/ml) (HR = 2.34; 95% CI, 1.30-4.02), tumor diameter on CT (>2.0 cm) (HR = 1.91; 95% CI, 1.18-3.13), and VDT (HR = 4.03; 95% CI, 2.41-6.93) as significantly independent worse prognostic factors for DFS.

CONCLUSIONS

The VDT value could be a useful prognostic factor in clinical T1 solid NSCLC.

Lobe-Specific Analysis of Sublobar Lung Resection for NSCLC Patients with Tumors ≤ 2 cm

Simple Summary

With the increase of the use of sublobar resection, the optimal strategy for early-stage NSCLC patients is essential. Previous studies showed tumors in different lobes are associated with different prognoses after radiotherapy and immunotherapy, inspiring us that each lobes had a different prognosis. Thus, we investigated the best surgical procedure for sublobar resection in patients with NSCLC ≤ 2 cm based on a lobe-specific analysis using propensity score matching. The results of this study will make it easier for surgeons to screen out patients with NSCLC ≤ 2 cm for segmentectomy or wedge resection, although this must be validated in larger cohorts.

Abstract

(1) Background: Sublobar resection can be used as an alternative surgical strategy for early-stage non-small-cell lung cancer (NSCLC) patients. However, the choice between wedge resection and segmentectomy remains contentious. In this study, we investigated the optimal surgical procedure for sublobar resection in patients with NSCLC ≤ 2 cm with a lobe-specific analysis; (2) Methods: Data for patients with T1N0M0 with a diameter of ≤2 cm who had undergone sublobar resection were retrieved. Propensity score matching (PSM) was used to reduce the inherent bias, and the Kaplan–Meier method and log-rank tests were used to assess the differences in survival; (3) Results: A total of 1882 patients were identified after the PSM. Patients with NSCLC ≤ 2 cm who had undergone segmentectomy showed better survival than those who had undergone wedge resection. However, when NSCLC was ≤1 cm, there was no significant difference in OS between the two groups. This demonstrated an OS advantage of segmentectomy over wedge resection for patients with NSCLC tumors of 1–2 cm (p = 0.024). Further analysis indicated that this survival benefit was only observed in patients with right upper NSCLC of 1–2 cm, but not with NSCLC in the other four lobes; (4) Conclusions: Segmentectomy showed a greater survival benefit than wedge resection only in patients with NSCLC of 1–2 cm, particularly those with primary tumors in the right upper lobe. Therefore, we propose a lobe-specific sublobar resection strategy for early-stage NSCLC patients (tumors of 1–2 cm) who cannot tolerate lobectomy.

A guide for managing patients with stage I NSCLC: deciding between lobectomy, segmentectomy, wedge, SBRT and ablation-part 2: systematic review of evidence regarding resection extent in generally healthy patients

Background

Clinical decision-making for patients with stage I lung cancer is complex. It involves multiple options (lobectomy, segmentectomy, wedge, stereotactic body radiotherapy, thermal ablation), weighing multiple outcomes (e.g., short-, intermediate-, long-term) and multiple aspects of each (e.g., magnitude of a difference, the degree of confidence in the evidence, and the applicability to the patient and setting at hand). A structure is needed to summarize the relevant evidence for an individual patient and to identify which outcomes have the greatest impact on the decision-making.

Methods

A PubMed systematic review from 2000-2021 of outcomes after lobectomy, segmentectomy and wedge resection in generally healthy patients is the focus of this paper. Evidence was abstracted from randomized trials and non-randomized comparisons with at least some adjustment for confounders. The analysis involved careful assessment, including characteristics of patients, settings, residual confounding etc. to expose degrees of uncertainty and applicability to individual patients. Evidence is summarized that provides an at-a-glance overall impression as well as the ability to delve into layers of details of the patients, settings and treatments involved.

Results

In healthy patients there is no short-term benefit to sublobar resection vs. lobectomy in randomized and non-randomized comparisons. A detriment in long-term outcomes is demonstrated by adjusted non-randomized comparisons, more marked for wedge than segmentectomy. Quality-of-life data is confounded by the use of video-assisted approaches; evidence suggests the approach has more impact than the resection extent. Differences in pulmonary function tests by resection extent are not clinically meaningful in healthy patients, especially for multi-segmentectomy vs. lobectomy. The margin distance is associated with the risk of recurrence.

Conclusions

A systematic, comprehensive summary of evidence regarding resection extent in healthy patients with attention to aspects of applicability, uncertainty and effect modifiers provides a foundation on which to build a framework for individualized clinical decision-making.

A guide for managing patients with stage I NSCLC: deciding between lobectomy, segmentectomy, wedge, SBRT and ablation-part 3: systematic review of evidence regarding surgery in compromised patients or specific tumors

Background

Clinical decision-making for patients with stage I lung cancer is complex. It involves multiple options [lobectomy, segmentectomy, wedge, stereotactic body radiotherapy (SBRT), thermal ablation], weighing multiple outcomes (e.g., short-, intermediate-, long-term) and multiple aspects of each (e.g., magnitude of a difference, the degree of confidence in the evidence, and the applicability to the patient and setting at hand). A structure is needed to summarize the relevant evidence for an individual patient and to identify which outcomes have the greatest impact on the decision-making.

Methods

A PubMed systematic review from 2000-2021 of outcomes after lobectomy, segmentectomy and wedge resection in older patients, patients with limited pulmonary reserve and favorable tumors is the focus of this paper. Evidence was abstracted from randomized trials and non-randomized comparisons (NRCs) with adjustment for confounders. The analysis involved careful assessment, including characteristics of patients, settings, residual confounding etc. to expose degrees of uncertainty and applicability to individual patients. Evidence is summarized that provides an at-a-glance overall impression as well as the ability to delve into layers of details of the patients, settings and treatments involved.

Results

In older patients, perioperative mortality is minimally altered by resection extent and only slightly affected by increasing age; sublobar resection may slightly decrease morbidity. Long-term outcomes are worse after lesser resection; the difference is slightly attenuated with increasing age. Reported short-term outcomes are quite acceptable in (selected) patients with severely limited pulmonary reserve, not clearly altered by resection extent but substantially improved by a minimally invasive approach. Quality-of-life (QOL) and impact on pulmonary function hasn't been well studied, but there appears to be little difference by resection extent in older or compromised patients. Patient selection is paramount but not well defined. Ground-glass and screen-detected tumors exhibit favorable long-term outcomes regardless of resection extent; however solid tumors <1 cm are not a reliably favorable group.

Conclusions

A systematic, comprehensive summary of evidence regarding resection extent in compromised patients and favorable tumors with attention to aspects of applicability, uncertainty and effect modifiers provides a foundation for a framework for individualized decision-making.

Application Research of Three-Dimensional Printing Technology and Three-Dimensional Computed Tomography in Segmentectomy

Background

To compare the application of the emerging 3D printing technology and 3D-CT in segmentectomy. And to explore the advantages of 3D printing technology in thoracoscopic segmentectomy.

Methods

We collected the clinical data of 118 patients undergoing thoracoscopic segmentectomy from January 2019 to April 2021 at the Thoracic Surgery Department, the Dianjiang People's Hospital of Chongqing and Southwest Hospital. Among them, 61 patients were in the 3D printing group and 57 patients were in the 3D-CT group respectively. The perioperative data of these two groups of patients were analyzed respectively.

Results

There were no significant differences between the two groups in age, gender, tumor diameter, pathology, the preoperative complications of diabetes and heart disease. However, the patients with the complications of hypertension in the 3D printing group are significantly more than the 3D-CT group (P = 0.003). Compared with the 3D-CT group, patients in the 3D printing group had significantly shorter operation time (162.7 ± 47.0 vs. 190.3 ± 56.9 min, P = 0.006), less intraoperative fluid input (1,158.5 ± 290.2 vs. 1,433.2 ± 653.3, P = 0.013), and less total intraoperative fluid output, including intraoperative blood loss, urine excretion, and other fluid loss. In addition, there were no statistically significant differences in intraoperative blood loss, 24 h pleural fluid volume, 48 h pleural fluid volume, postoperative chest tube duration, postoperative hospital stay and complications between the two groups of patients (P &gt; 0.05).

Conclusions

In thoracoscopic segmentectomy, the application of 3D printing technology shortens the operation time, reduces intraoperative fluid input and output, guides the operation more safely and effectively, and has better clinical application value.

Extent of Resection Influences Survival in Early-Stage Lung Cancer with Occult Nodal Disease

BACKGROUND

Minimal literature exists evaluating the impact of the extent of resection on survival in patients with small, early-stage non-small cell lung cancer (NSCLC) found to have occult nodal disease (OND). We hypothesized that sublobar resection has comparable overall survival to patients undergoing lobectomy for clinical Stage IA NSCLC that harbors OND.

METHODS

The National Cancer Database was reviewed for identification of patients with clinical Stage IA NSCLC who underwent wedge resection, segmentectomy or lobectomy and were found to have OND. Overall survival was compared between groups and a multivariate Cox-Regression model identified factors associated with worse survival.

RESULTS

OND occurred in 6.1% of all patients with clinical Stage IA disease undergoing resection. Patients undergoing wedge resection and segmentectomy found to have OND were older (67.6 ± 9.6 vs. 66.1 ± 9.3 vs. 65.6 ± 9.5, p=0.004), and had more advanced pathologic stage (pStage III: 68.7% vs. 50.5% vs. 41.5%, p<0.001) than those receiving lobectomy. There was no difference in the median overall survival between segmentectomy and lobectomy (68.5 months vs. 57.6, p=0.200.) However, wedge resection was independently associated with worse overall survival when controlling for other preoperative variables, hazard ratio: 1.23 (1.01 - 1.51), p=0.042.

CONCLUSIONS

Review of the National Cancer Database suggests that there is no improvement in overall survival in patients undergoing lobectomy versus segmentectomy in carefully selected patients with clinical Stage IA NSCLC harboring occult nodal disease. However, those undergoing wedge resection may have worse overall survival than those undergoing both lobectomy and segmentectomy.

Bibliometric Analysis of 50 Most Cited Articles Comparing Lobectomy with Sublobar Resection

BACKGROUND

 Recent years have seen an increase in the number of studies of the sublobar resection approach in non-small cell lung cancer (NSCLC) surgery. The purpose of this bibliometric analysis is to assess the significance and impact of articles comparing sublobar resection and lobectomy in NSCLC surgery.

MATERIAL AND METHODS

 The Web of Science database was searched to identify studies comparing sublobar resection and lobectomy in NSCLC surgery published between 2005 and 2020 (accessed: September 11, 2020). The 50 most cited articles were analyzed by years, countries, authors, authors' affiliations, journals, journals' addresses, and impact factors.

RESULTS

 The bibliometric analysis revealed that the most cited article had 443 citations, while the total number of citations of all articles was 2,820. The mean number of citations, in turn, was 56.4 ± 75.62 (1-443) times. The highest number of publications over the past 15 years was in 2016, with eight articles. The Annals of Thoracic Surgery (n = 10; 20%) had the highest number of publications on the list. The articles included in the present study were mostly (n = 35, 70%) published in U.S. journals. While multiple subject matters and analyses were presented by many studies, survival was the topic of greatest interest, with 37 (74%) studies.

CONCLUSION

 This study revealed that interest in studies comparing sublobar resection with lobectomy has increased in recent years. It also presents both quantitative and qualitative analyses of the most cited articles in the literature on this topic. Therefore, it can serve as a guide for researchers.

Clinicopathological and computed tomographic features associated with occult lymph node metastasis in patients with peripheral solid non-small cell lung cancer

OBJECTIVES

To investigate the value of combining clinicopathological characteristics with computed tomographic (CT) features of tumours for predicting occult lymph node metastasis (OLNM) in peripheral solid non-small cell lung cancer (PS-NSCLC).

METHODS

The study included 478 NSCLC clinically N0 (cN0) patients who underwent lobectomy and systemic lymph node dissection from January 2014 to August 2019. Patients were classified into OLNM and negative lymph node metastasis (NLNM) groups. The CT features of non-metastatic and metastatic lymph nodes with a largest short-diameter > 5 mm were compared in the OLNM group. Thereafter, the clinicopathological characteristics and CT morphological features of tumours were compared between both groups. Multivariable logistic regression analysis and receiver-operating characteristic curve were developed.

RESULTS

CT images detected 103 metastatic and 705 non-metastatic lymph nodes, and no significant differences in CT features of lymph nodes were found in all 161 OLNM patients (P > 0.05). For both groups, sex, carcinoembryonic antigen and pathological type differed significantly (all P < 0.05), while tumour size, necrosis, calcification, vascular convergence, pleural involvement, and the shortest interval of tumour-pleura differed significantly on CT images (all P < 0.05). Multivariable logistic regression analysis showed that carcinoembryonic antigen > 5.00 ng/ml, adenocarcinoma, absence of vascular convergence, and pleural involvement of Type II (one linear or cord-like pleural tag or tumour abut to the pleura with a broad base observed on both lung and mediastinal window images) were independent predicting factors of OLNM.

CONCLUSIONS

CT findings of lymph nodes can provide limited value and integrating clinicopathological characteristics with the CT morphological features of tumours is helpful in predicting OLNM in patients with PS-NSCLC.

Prognostic relevance of pleural invasion for resected NSCLC patients undergoing adjuvant treatments: A propensity score-matched analysis of SEER database

BACKGROUND

Adjuvant chemotherapy demonstrated a clear benefit in resected non-small cell lung cancer (NSCLC) with nodal disease (stages II-III), and a minimal benefit in tumors >4 cm (stage II, TNM 8th edition). Pleural invasion (PL), classified as visceral pleural invasion (VPI, which includes PL1 and PL2, and parietal pleural invasion (PL3), is an established negative prognostic factor. However, whether PL should influence the decisional algorithm of postoperative chemotherapy is controversial.

METHODS

A survival analysis of NSCLC patients who underwent radical surgery between 2010 and 2015 included in the SEER database was performed. Tumor stage and size, number of examined and positive nodes, histology, PL, and treatment data were extracted. Propensity score matching was performed. The benefit of chemotherapy was analyzed in two subgroups: standard of care (SOC), including patients with positive nodes or tumors ≥ 4 cm; non-SOC, including patients with tumors < 4 cm and negative nodes.

RESULTS

Records of 30,858 patients were extracted. 11,708 patients were included in the propensity score-matched analysis. In the SOC subgroup, including 8089 patients, all pleural invasion degrees were associated with progressively increased risk for death and shorter overall survival (OS), independently from chemotherapy administration. However, chemotherapy significantly improved the median OS regardless of the extent of PL. In the non-SOC subgroup, including 3619 patients, only PL3 was associated with increased mortality. The administration of chemotherapy did not improve survival outcomes.

CONCLUSION

Chemotherapy should be strongly recommended in patients in the SOC-subgroup with pleural invasion. VPI is not associated with unfavorable prognosis in the non-SOC subgroup.

Benefit of three-dimensional image simulation in surgical resection of early stage lung cancer

BACKGROUND

The present study investigated the oncological outcomes of clinical stage IA2 non-small cell lung cancer that was treated using preoperative simulation and surgical resection.

METHODS

The data of patients who underwent surgical resection for clinical stage IA2 non-small cell lung cancer between January 2002 and June 2018 were reviewed. Preoperative simulations were indicated for patients with centrally located tumors who can undergo anatomic resection. The clinical features, imaging characteristics of the tumors, surgical approaches and outcomes were analyzed.

RESULTS

Of the 1086 identified patients, 281 patients with clinical stage IA2 non-small cell lung were enrolled and categorized into 2 groups, with and without preoperative simulation. The tumor location, maximum standard uptake value, histological grade, disease-free survival and disease recurrence were significantly different between the 2 groups. For the group with preoperative simulations, 70.7% of the patients underwent anatomic resection, and 79.7% of the patients without preoperative simulations underwent anatomic resection (P <0.001). Patients with preoperative simulations had fewer relapses (2%) than patients without preoperative simulations (11.5%, P < 0.01).

CONCLUSIONS

Preoperative simulation confirmed the relationship between the tumor and surrounding blood vessels and bronchus and ensured an oncological safety margin. 3D simulations are a useful and feasible tool for planar operative procedures, satisfy the requirements for early-stage NSCLC. These results are promising but preliminary and more extended follow-up is needed.

Identifying Lung Cancer Patients Suitable for Segmentectomy: A Brief Review

Background: In 1995, a clinical randomized controlled study (RCT) conducted by the Lung Cancer Study Group (LCSG) pointed out that the lobectomy was the gold standard for treating early lung cancer. However, with the development of technology, the results of several retrospective studies have shown that the efficacy of pulmonary segmentectomy is equivalent to that of lobectomy. Currently, it is still controversial whether segmental resection or lobectomy should be performed for early lung cancer. Thus, we aim to summarize the indications of segmentectomy.

Methods: To conduct the review, previous researches involving indications of segmentectomy were collected from the literature using Pubmed. These articles were published and accepted in English in the medical literature from 2013 to 2020. We have focused on segmentectomy and its indications.

Results: A total of 176 articles were retrieved from the Pubmed database, of which 31 articles included indications for segmentectomy. We summarized the relevant content, and the potential and prospect of segmentectomy for the treatment of lung cancer were emphasized.

Conclusions: These findings have a number of important implications for future practice. Pulmonary segmentectomy is a very vital surgical procedure for select patients with lung cancer, which provides a novel approach for the treatment of lung cancer and the survival of lung cancer patients.

Segmentectomy or lobectomy for early-stage non-small-cell lung cancer: a systematic review and meta-analysis

OBJECTIVES

The role of segmentectomy in early-stage non-small-cell lung cancer (NSCLC) remains a matter of debate. We performed a meta-analysis to evaluate the oncological outcomes following segmentectomy versus lobectomy for stage I, stage IA only and stage IA <2 cm only.

METHODS

We systematically searched the literature for articles reporting on overall survival (OS), cancer-specific survival (CSS) or recurrence-free survival (RFS). The hazard ratios (HRs) were retrieved and pooled using an inverse variance-weighted approach.

RESULTS

Twenty-eight studies were included in the analysis. In stage I, segmentectomy was found to be inferior to lobectomy for all 3 outcomes with HR: 1.25 (P = 0.01) for OS, 1.59 (P = 0.02) for CSS and 1.40 (P < 0.001) for RFS. In stage IA, the differences were significant for OS and CSS, though not for RFS with HR: 1.31 (P = 0.04), 1.56 (P = 0.02) and 1.22 (P = 0.11), respectively. In stage IA <2 cm, no significant differences were found between segmentectomy and lobectomy with HR: 1.13 (P = 0.37) for OS, 1.02 (P = 0.95) for CSS and 1.24 (P = 0.11) for RFS.

CONCLUSIONS

For stages I and IA, lobectomy showed superior results whereas for tumours <2 cm, our study did not find significant differences in oncological outcomes between both groups. These results suggest that segmentectomy might be a valuable alternative to lobectomy for NSCLC in tumours <2 cm.

Survival and Recurrence Following Wedge Resection Versus Lobectomy for Early-Stage Non-Small Cell Lung Cancer

To determine if wedge resection is equivalent to lobectomy for Stage I Non-Small Cell Lung Cancer (NSCLC) and to evaluate the impact of radiologic and pathologic variables not available in large national databases. Records were reviewed from 2010-2016 for patients with pathologic Stage I NSCLC who underwent wedge resection or lobectomy. Propensity score matching was performed on pre-operative variables and patients with ≥1 lymph node removed. Clinical variables were compared. Kaplan-Meier curves and multivariable Cox proportional hazard models for 5-year overall survival (OS), disease-free (DFS), and locoregional-recurrence-free survival (LRFS) were created. A total of 1086 patients met inclusion criteria; 391 lobectomies and 695 wedge resections. Propensity score matching yielded 167 pairs of lobectomy and wedge resection patients. Complications were fewer for wedge resections than lobectomies, 19.2% for wedge resection patients vs 34.1% for lobectomy patients, p < 0.01. OS was equivalent between groups, 86.2% for lobectomy patients vs 83.4% for wedge resection patients p = 0.47. DFS was similar, 79.0% for lobectomy patients vs 72.5% for wedge resection patients p = 0.10. Overall LRFS was worse in wedge resection patients vs lobectomy patients, 82.0% vs 93.4% p < 0.01. However, in the matched wedge resection patients with a margin >10 mm the LRFS was equal to that of lobectomy patients, 86.4% for wedge resection patients vs 91.8% for lobectomy patients p = 0.140. Patients with Stage I NSCLC can experience similar OS, DFS, and LRFS with wedge resection as compared to lobectomy, when wedge resection margins are >10 mm and appropriate lymph node dissection is performed.

Should sublobar resection be offered for screening-detected lung nodules?

The increasing use of low-dose CT for screening for lung cancer will inevitably identify many small, asymptomatic lung nodules and ground-glass opacities (GGOs). Current guidelines for the management of screening-detected lesions tend to advise a conservative approach based on serial imaging and intervention only if ‘suspicious’ features emerge. However, more recent developments in thoracic surgery and in the understanding of the screening-detected lesions themselves prompt some pertinent questions over this conservatism. Is CT surveillance sufficiently reliable to exclude malignancy? Is it really necessary to hold back on operative biopsy and resection given modern surgical safety and efficacy? Is the option for early surgical therapy a viable one—especially with the availability of sublobar resection today? Modern data suggests that the risk of inaction for some screening-detected lesions may be higher than expected, whereas the potential harm of surgical intervention may be substantially reduced by sublobar resection and the latest minimally invasive surgical techniques. A more pro-active approach towards offering surgery for screening-detected lesions should now be considered.

Clinical significance of intrapulmonary lymph node dissection in pathological stage IA non-small cell lung cancer: A propensity score matching analysis

Background

This study aimed to investigate the prognostic impact of intrapulmonary lymph node (ILN, stations 13–14) dissection on disease‐free survival (DFS) in stage IA non‐small cell lung cancer (NSCLC) patients in order to facilitate a more suitable determination of surgical strategies for early‐stage cases.

Methods

We retrospectively analyzed 416 patients with pathological stage IA NSCLC from February 2016 to November 2019. The patients were divided into a group with ILN dissection (ILN^D+ group) and a group without ILN dissection (ILN^D‐ group). DFS was compared using the Kaplan–Meier method and compared statistically using the log‐rank test before and after propensity score matching (PSM). Subgroup analysis of DFS stratified based on tumor size was also calculated.

Results

Both before and after PSM, the four‐year DFS of the ILN^D+ group was greatly increased compared to that of ILN^D‐ group (90.1% vs. 79.7%, p = 0.003; 95.5% vs. 80.6%, p = 0.003, respectively) and multivariable cox regression analysis revealed ILN dissection was an independent factor favoring DFS in stage IA NSCLC (p = 0.016 and p = 0.015, respectively). Subgroup analysis revealed the four‐year DFS was comparable between the ILN ^D+ and ILN^D‐ groups with regard to tumor size ≤1.5 cm (90.6% vs. 92.7%, p = 0.715). However, the ILN ^D+ group was found to have a better oncological outcome compared with the ILN^D‐ group with regard to tumor size >1.5 cm (90.0% vs. 73.8%, p = 0.003).

Conclusions

The prognostic impact of ILN dissection on patients with stage IA NSCLC appears to be significantly influenced by tumor size, and this should be taken into account when choosing the most appropriate therapeutic modality.

Predicting occult lymph node metastasis by nomogram in patients with lung adenocarcinoma ≤2 cm

Background: Previous researches had not proposed any prediction models for occult lymph node metastasis (OLNM). Considering the occurrence of OLNM and the importance of OLNM management, we aimed to develop a nomogram to predict OLNM of patients with lung adenocarcinoma ≤2 cm. Methods: Characteristics of patients with lung adenocarcinoma of ≤2 cm diameter at the Peking Union Medical College Hospital were retrospectively reviewed. Univariate and multivariate logistic regressions were performed. A nomogram model was developed. The concordance index (C-index) and calibration and decision curves were used to evaluate the predictive ability. Results: A total of 473 patients were enrolled, with an OLNM incidence of 7.4%. Four factors were selected as risk factors. The model had a C-index of 0.932. Calibration and decision curves were determined. Conclusion: Patients with pure ground-glass opacity (pGGO) or noninvasive adenocarcinoma have significantly lower risk of OLNM. SUV_max, CEA, micropapillary and solid component were identified as independent risk factors. The nomogram model was effective in predicting OLNM preoperatively.

A propensity-matched analysis of stereotactic body radiotherapy and sublobar resection for stage I non-small cell lung cancer in patients at high risk for lobectomy: the results in a Chinese population

Background

To investigate the comparative effectiveness of stereotactic body radiotherapy (SBRT) and sublobar resection (SLR) in patients with stage I non-small cell lung cancer (NSCLC) considered to be high-risk lobectomy patients.

Methods

From January 2012 to December 2015, patients who underwent SBRT or SLR for clinical stage I NSCLC were examined retrospectively. Propensity score matching (PSM) was performed to reduce selection bias in SBRT and SLR patients.

Results

Data from 86 SBRT and 79 SLR patients was collected. Median follow-up periods of the SBRT and SLR groups were 32 and 37 months, respectively. Patients treated with SBRT exhibited significantly higher age, higher likelihood of being male, larger tumor diameter, lower forced expiratory volume in 1 second (FEV1), and poorer performance status compared with SLR patients. There were no significant differences between SBRT and SLR patients for 3-year overall survival (OS) (80.3% and 82.3%, P=0.405), cause-specific survival (CSS) (81.3% and 83.4%, P=0.383), and local control (LC) (89.7% and 86.0%, P=0.501). Forty-nine patients were identified from each group after performing PSM. After patients were matched for age, gender, performance status, tumor characteristics and pulmonary function, no significant differences were observed in 3-year OS (85.4% and 73.3%, P=0.649), CSS (87.2% and 74.9%, P=0.637) and LC (95.6% and 82.1%, P=0.055). Prevalence of significant adverse events (grade 3 or worse) was 0% and 10.2% in the matched SBRT and SLR groups (P=0.056), respectively.

Conclusions

Disease control and survival in the SBRT patients was equivalent to that seen in SLR patients with stage I NSCLC considered high-risk lobectomy candidates. SBRT could therefore be an alternative option to SLR in treating patients with a high operative risk.

Surgical Consideration Based on Lymph Nodes Spread Patterns in Patients with Peripheral Right Middle Non-small Cell Lung Cancer 3 cm or Less

BACKGROUND

The optimal extent of lung resection and lymph nodes dissection for peripheral early-stage right middle non-small cell lung cancer (NSCLC) still remains controversial. In this study, we analyzed the patterns of lymph nodes metastasis (LNM) of patients with peripheral right middle NSCLC ≤ 3 cm, aiming to provide evidences for surgical choice for early-stage peripheral right middle lobe NSCLC.

METHODS

We retrospectively investigated the clinical and pathological data of patients diagnosed with peripheral right middle lobe NSCLC ≤ 3 cm between January 2015 and December 2019. The LNM patterns were analyzed by tumor size.

RESULTS

A total of 60 patients were included for analysis. The tumor size was preoperatively divided as follows: ≤ 1 cm (13 patients); > 1 cm but ≤ 2 cm (36 patients); > 2 cm but ≤ 3 cm (11 patients). Fifty-four patients were categorized as N0 group, 1 patient as N1 group, and 5 patients as N2 group. In the upper zone, 3 patients were found to have LNM. In the subcarinal zone, another 3 patients had LNM. But the lymph nodes of all these patients were negative in the lower zone. In station 10, 1 patient (1.67%) was found to have LNM, while in station 11-13, 2 patients (3.33%) were found to have LNM.

CONCLUSION

For the right middle lobe peripheral NSCLC ≤ 1 cm, sublobar resection with lymph node sampling may be a feasible treatment. For cancers > 1 cm but ≤ 2 cm, lobectomy with lobe-specific lymph node dissection (especially station 2R and 4R) may be a preferred choice. For tumors > 2 cm but ≤ 3 cm, lobectomy with systematic lymph node dissection may still be the standard of care.

Stereotactic body radiation therapy (SBRT) for patients with stage I non-small cell lung cancer is applicable to more tumors than sublobar resection

Background

Virtually all patients with medically inoperable stage I non-small cell lung cancer (NSCLC) can receive stereotactic body radiation therapy. However, the percentage of such patients in whom sublobar resection is technically feasible is unknown. This discrepancy can confound clinical trial eligibility and designs comparing stereotactic body radiation therapy vs. sublobar resection.

Methods

A total of 137 patients treated with stereotactic body radiation therapy for lung lesions (3/2013–11/2017) underwent retrospective review. Diagnostic CT chest and PET/CT images, stereotactic body radiation therapy dates, and demographic data were collected on 100 of 137 patients. Two experienced board-certified thoracic surgeons independently reviewed anonymized patients’ pre-stereotactic body radiation therapy diagnostic imaging and completed a custom survey about the technical feasibility of sublobar resection for each patient. Interrater agreement was measured using Cohen’s kappa coefficient by bootstrap methodology. Summary statistics were performed for baseline demographics and tumor characteristics.

Results

Of the 100 patients, 57% were female, with median age of 75 years (range, 52–95 years) and Karnofsky Performance Status of 80 (range, 40–100). Most patients (61%) had Stage IA1, T1a tumors. For interrater agreement analysis, one patient was removed from each cohort due to inability to locate tumor on images, leaving 98 patients analyzed. Comparing Surgeon #1 vs. Surgeon #2, 64 (65.3%) vs. 69 (70.3%) of tumors were thought eligible for sublobar resection, respectively (κ=0.414).

Conclusions

Stereotactic body radiation therapy for stage I NSCLC is applicable to more tumors than sublobar resection, with ~30–35% of stereotactic body radiation therapy patients unable to undergo sublobar resection assessed by pretreatment diagnostic imaging based on technical grounds. This study illustrates that clinical trials comparing stereotactic body radiation therapy vs. sublobar resection are limited to only a subpopulation of patients with stage I NSCLC.

The accuracy of cone-beam computed tomography and augmented fluoroscopy-guided bronchoscopic marking of multiple small-sized pulmonary nodules in a hybrid operating room: a retrospective cohort study

Background

For the minimally invasive excision of small-sized pulmonary nodules, bronchoscopic markings are increasingly being performed owing to advancements in video-assisted thoracic surgery (VATS). Hybrid operating room equipment is utilized for bronchoscopic VATS markings. We aimed to compare the marking accuracy between bronchoscopic VATS and other marking techniques such as computed tomography-guided percutaneous marking and conventional X-ray fluoroscopy-guided bronchoscopic marking.

Methods

Patients with small-sized pulmonary nodules scheduled to undergo VATS were enrolled in the study. A mixture of 50 to 100 µL of diluted indocyanine green and iopamidol was injected adjacent to the pulmonary nodules as a VATS marker. Patients receiving each of the three image-guided techniques were categorized into group A (computed tomography-guided percutaneous injection), group B (X-ray fluoroscopy-guided virtual bronchoscopy-assisted bronchoscope injection), and group C (cone-beam computed tomography and augmented fluoroscopy-guided virtual bronchoscope-assisted bronchoscopic injection in the hybrid operating room). VATS marking accuracy and procedural complications were compared among the three groups.

Results

In total, 61 patients with 73 pulmonary nodules were eligible for analysis. VATS marking was successful for 15/16 nodules in group A, 28/30 nodules in group B, and 25/27 nodules in group C. Marking accuracy was 5.75±4.59, 15.00±14.02, and 6.05±6.11 (mm), respectively. Multiple markings were successful in 0/1 (0%), 5/6 (83.3%), and 5/5 (100.0%) nodules in groups A, B, and C, respectively. A small pneumothorax occurred in 3/15 (20.0%) patients in group A.

Conclusions

The cone-beam computed tomography and augmented fluoroscopy-guided bronchoscopic approach performed in a hybrid operating room is accurate and equivalent to the computed tomography-guided percutaneous approach, and it enables the VATS marking of multiple pulmonary nodules without causing a secondary pneumothorax.

Adjuvant treatment can improve prognosis in patients with non-small cell lung cancer ≤3 cm after sublobectomy: a propensity score analysis

Background

Numerous retrospective studies have reported that sublobectomy has a poorer prognosis than lobectomy in patients with early-stage lung cancer. The purpose of this study was to determine whether adjuvant treatment could improve the prognosis of patients with non-small cell lung cancer (NSCLC) ≤3 cm after sublobectomy.

Methods

We collected data from 17,763 patients with T1N0M0 NSCLC after surgery from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. Kaplan-Meier curves were generated to compare the overall survival (OS) rates and the lung cancer-specific survival (LCSS) rates. Cox proportional hazards regressions were performed to discover the independent risk factors for both the OS and LCSS rates.

Results

Lobectomy was performed in 12,428 cases and sublobectomy was performed in 5,335 cases. In the sublobectomy group, among the 394 patients treated with adjuvant therapy, larger tumor diameter, a lower number of lymph node dissections, and more wedge resections were observed in the patients treated with adjuvant therapy. In the subsequent survival analysis, the OS and LCSS rates of adjuvant therapy patients showed a significant survival advantage over those treated with sublobectomy alone (P<0.05). The survival analysis was performed again after propensity match scoring, generating similar results (P<0.05). There was still a significant difference in OS between adjuvant therapy and lobectomy alone (P<0.05).

Conclusions

Chemoradiotherapy can improve the OS of patients with NSCLC ≤3 cm after sublobectomy and reduce death caused by tumors. Therefore, when patients cannot tolerate lobectomy or are given inappropriate sublobectomy, adjuvant therapy can improve the prognosis of patients.

Feasibility of limited resection for peripheral small-sized non-small cell lung cancer: a retrospective single-center-based study

PURPOSE

This study aimed to establish new criteria for limited resection of non-small cell lung cancer (NSCLC) based on computed tomography findings and maximum standardized uptake value (SUVmax).

METHODS

Between December 2007 and December 2015, 611 patients underwent lung cancer surgery; of these, 70 with cT1aN0M0 who underwent limited resection were enrolled. Criteria for undergoing intentional limited resection (ILR) were (1) tumor ground-glass opacity (GGO) ratio of ≥ 0.75 and (2) tumor SUVmax ≤ 1.5. Patients who met criteria (1) and (2) underwent partial resection, and those who only met criteria (2) underwent segmentectomy as ILR. The control group was subjected to limited surgery without meeting the criteria.

RESULTS

Overall, 45 and 25 patients who met the criteria were included in the ILR and control groups, respectively. In the ILR group, 13 patients underwent partial resection, and 32 underwent segmentectomy; in the control group, 18 patients underwent partial resection and 7 underwent segmentectomy. According to our criteria, no relapsed cases occurred in the ILR group, although six patients showed recurrence of lung cancer in the control group. The 5-year overall survival (OS) rates in the ILR and control groups were 100% and 67.7%, respectively, and the relapse-free survival (RFS) rates were 100% and 61.6%, respectively. The log-rank test showed that this difference was statistically significant (OS: P < 0.0001, RFS: P < 0.0001).

CONCLUSIONS

SUVmax may serve as a predictive marker of recurrence to determine the treatment strategy for patients with NSCLC. Patients with low GGO ratio and low SUVmax may be cured by limited resection.

Association of Survival With Adjuvant Chemotherapy Among Patients With Early-Stage Non-Small Cell Lung Cancer With vs Without High-Risk Clinicopathologic Features

Importance

Tumor size larger than 4 cm is accepted as an indication for adjuvant chemotherapy in patients with node-negative non-small cell lung cancer (NSCLC). Treatment guidelines suggest that high-risk features are also associated with the efficacy of adjuvant chemotherapy among patients with early-stage NSCLC, yet this association is understudied.

Objective

To assess the association between adjuvant chemotherapy and survival in the presence and absence of high-risk pathologic features in patients with node-negative early-stage NSCLC.

Design, Setting, and Participants

This retrospective cohort study using data from the National Cancer Database included 50 814 treatment-naive patients with a completely resected node-negative NSCLC diagnosed between January 1, 2010, and December 31, 2015. The study was limited to patients who survived at least 6 weeks after surgery (ie, estimated median time to initiate adjuvant chemotherapy after surgery) to mitigate immortal time bias. Statistical analysis was performed from December 1, 2018, to February 29, 2020.

Exposures

Adjuvant chemotherapy use vs observation, stratified according to the presence or absence of high-risk pathologic features (visceral pleural invasion, lymphovascular invasion, and high-grade histologic findings), sublobar surgery, and tumor size.

Main Outcomes and Measures

The association of high-risk pathologic features with survival after adjuvant chemotherapy vs observation was evaluated using Cox proportional hazards regression models.

Results

Overall, 50 814 eligible patients with NSCLC (27 365 women [53.9%]; mean [SD] age, 67.4 [9.5] years]) were identified, including 4220 (8.3%) who received adjuvant chemotherapy and 46 594 (91.7%) who did not receive adjuvant chemotherapy. Among patients with tumors 3 cm or smaller, chemotherapy was not associated with improved survival (hazard ratio [HR], 1.10; 95% CI, 0.96-1.26; P = .17). For patients with tumors larger than 3 cm to 4 cm, adjuvant chemotherapy was associated with a survival benefit among patients who underwent sublobar surgery (HR, 0.72; 95% CI, 0.56-0.93; P = .004). For tumors larger than 4 cm to 5 cm, a survival benefit was associated with adjuvant chemotherapy only in patients with at least 1 high-risk pathologic feature (HR, 0.67; 95% CI, 0.56-0.80; P = .02). For tumors larger than 5 cm, adjuvant chemotherapy was associated with a survival benefit irrespective of the presence of high-risk pathologic features (HR, 0.75; 95% CI, 0.61-0.91; P = .004).

Conclusions and Relevance

In this cohort study, tumor size alone was not associated with improved efficacy of adjuvant chemotherapy in patients with early-stage (node-negative) NSCLC. High-risk clinicopathologic features and tumor size should be considered simultaneously when evaluating patients with early-stage NSCLC for adjuvant chemotherapy.

Thermal Ablation Versus Wedge Resection for Stage I Non-small Cell Lung Cancer Based on the Eighth Edition of the TNM Classification: A Population Study of the US SEER Database

Background

The incidence rates of early-stage non-small cell lung cancer (NSCLC) are now increasing, and therapies such as thermal ablation have shown potential therapeutic promise. This study aimed to determine the influence of different surgical methods on overall survival (OS) and cancer-specific survival (CSS) in patients with stage I NSCLC.

Methods

Patients diagnosed with stage I NSCLC who had received thermal ablation or wedge resection between 2004 and 2014 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) was performed according to the surgical method. Kaplan–Meier curves and a Cox proportional hazard model were used to evaluate OS and CSS.

Results

In all, 4,372 patients with stage I NSCLC were included. Before PSM, the respective 3- and 5-year OS rates were 68.9 and 52.7% in the wedge resection group and 68.5 and 47.8% in the thermal ablation group (p < 0.0001); the corresponding CSS rates were 79.1 and 69.4% and 62.6 and 46.0% (p < 0.0001). After PSM, survival analysis showed that wedge resection had better OS (44.5% vs. 30.1%, p = 0.033) and CSS (63.5% vs. 46%, p = 0.038) than thermal ablation. After PSM, Cox regression showed that treatment was not associated with OS or CSS. For patients aged >75 years, thermal ablation showed similar OS and CSS as wedge resection (OS: 30.6% vs. 41.7%, p = 0.470; CSS: 46.4% vs. 64.1%, p = 0.100). After PSM, thermal ablation still had OS (30.6% vs. 41.0%, p = 0.470) and CSS (46.4% vs. 59.8%, p = 0.100) comparable to wedge resection.

Conclusion

For patients with stage I NSCLC who are unfit for lobectomy, thermal ablation could be a potential therapeutic option, especially for those >75 years old.

[Progress in Survival Prognosis of Segmentectomy for Early-stage Non-small Cell Lung Cancer]

Surgery is currently the most appropriate treatment for early-stage non-small cell lung cancer (NSCLC). Increasing unilateral or bilateral multiple primary lung cancer being found, segmentectomy has attracted wide attention for its unique advantages in the treatment for such tumors. Ground glass opacity dominant early-stage NSCLC is associated with a good prognosis and can be cured by segmentectomy, however, the treatment of solid-dominant NSCLC remains controversial owing to the invasive nature. With the in-depth study on the lymph node metastasis pathway, radiological characteristics and molecular biology of NSCLC, a large part of solid nodules with certain characteristics can also be cured by segmentectomy. This paper reviews the research status and progress about the indication of segmentectomy.
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Time trend of mediastinal lymph node dissection in stage IA non-small cell lung cancer patient who undergo lobectomy: a retrospective study of surveillance, epidemiology, and end results (SEER) database

Background

Although lobectomy with mediastinal lymph node dissection (MLND) is the first option for early-stage non-small cell lung cancer (NSCLC) patients, the time trends of MLND in stage IA NSCLC patients who undergo a lobectomy are not clear still.

Methods

We included stage IA NSCLC patients who underwent lobectomy or lobectomy with MLND between 2003 and 2013 in the SEER database. The time trend of MLND was compared among patients who underwent a lobectomy.

Results

For stage T1a patients, the lobectomy group and lobectomy with MLND group had no differences in postoperative overall survival (OS) (P = 0.34) or lung-cancer specific survival (LCSS) (P = 0.18) between 2003 and 2013. For stage T1b patients, the OS (P = 0.01) and LCSS (P = 0.01) were different between the lobectomy group and the lobectomy with MLND group in the period from 2003 to 2009; however, only OS (P = 0.04), not LCSS (P = 0.14), was different between the lobectomy group and the lobectomy with MLND group between 2009 and 2013. For T1c patients, the OS (P = 0.01) and LCSS (P = 0.02) were different between the two groups between 2003 and 2009 but not between 2009 and 2013 (P = 0.60; P = 0.39). From the Cox regression analysis, we found that the factors affecting OS/LCSS in T1b and T1c patients were age, sex, year of diagnosis, histology, and grade, in which year of diagnosis was the obvious factor (HR = 0.79, CI = 0.71–0.87; HR = 0.73, CI = 0.64–0.84).

Conclusions

There was a time trend in prognosis differences between the lobectomy group and lobectomy with MLND group for T1b and T1c stage NSCLC patients.

Video-assisted thoracoscopic surgery as the gold standard for lung cancer surgery

Surgical resection remains the only effective means of cure in the vast majority of patients with early-stage lung cancer. It can be performed via a traditional open approach (particularly thoracotomy) or a minimally invasive approach. VATS is 'keyhole' surgery in the chest, and was first used for lung cancer resection in the early 1990s. Since then, a large volume of evolving clinical evidence has confirmed that VATS lung cancer resection offered proven safety and feasibility, better patient-reported post-operative outcomes, less surgical trauma as quantified by objective outcome measures and equivalent or better survival than open surgery. This has firmly established VATS as the surgical approach of choice for early-stage lung cancer today. Although impressive new non-surgical lung cancer therapies have emerged in recent years, VATS is also being constantly rejuvenated by the development of 'next generation' VATS techniques, the refinement of VATS sublobar resection for selected patients, the utilization of bespoke post-operative recovery programmes for VATS and the synthesis of VATS into multi-modality lung cancer therapy. There is little doubt that VATS will remain as the gold standard for lung cancer surgery for the foreseeable future.

Surgical outcomes of second primary lung cancer after the extrapulmonary malignancy

OBJECTIVE

To study the surgical outcomes of patients with a second primary lung cancer after the extrapulmonary malignancy.

MATERIALS AND METHODS

Patients who underwent surgical resection for lung cancers between January 2005 and December 2014 were reviewed. Clinical data, imaging characteristics of tumors, surgical approaches, and outcomes were analyzed with a mean follow-up of 97 months.

RESULTS

Of 1075 patients, 166 (15.4%) had a second primary lung cancer after extrapulmonary malignancy. There were no differences in overall 5-year survival rates (81.8% for the group of lung cancer vs. 72.9% for the second primary lung cancer group, p = 0.069) and 5-year disease-free survival (70.1% for the lung cancer group vs. 70.3% for the second primary lung cancer group, p = 0.863) between the two groups. Gender, performance status, tumor size, and maximum standard uptake value (SUVmax) were significantly different between the two groups. After propensity-score matching analysis, patients in the group with lung cancers had better 5-year overall survival (88.1% vs. 72.1% for the group with second primary lung cancers, p = 0.016) and 5-year disease-free survival (80.6% vs. 70.3% for the group with second primary lung cancers; p = 0.054). In the second primary lung cancer group, the patients with preceding breast or thyroid cancers had better prognoses than did those with other extrapulmonary malignancy.

CONCLUSIONS

Second primary lung cancers following extrapulmonary malignancies were not uncommon. Surgical resection is considered for early stage secondary primary lung cancer after meticulous work up and result in fair outcome.

Survival Following Segmentectomy or Lobectomy in Patients With Stage IB Non-small-cell Lung Cancer

Background: Lobectomy with mediastinal lymph node dissection has always been recognized as the standardized treatment for early-stage non-small-cell lung cancer. However, the feasibility of segmentectomy performed in stage IB non-small-cell lung cancer (NSCLC) patients remains controversial. The present study aims to investigate whether the outcome of stage IB NSCLC patients undergoing segmentectomy was comparable to those who underwent lobectomy.

Method: We retrospectively collected data of 11,010 patients with primary stage IB non-small-cell lung cancer from the Surveillance, Epidemiology, and End Results database. Overall survival (OS) and lung cancer-specific survival (LCSS) were assessed among patients who were performed lobectomy or segmentectomy. To further assess the impact of the surgical procedures on patients with different tumor sizes, subgroups stratified by tumor size were analyzed.

Results: A total of 11,010 patients who were pathologically confirmed to be stage IB were included, of whom 10,453 received lobectomy and 557 received segmentectomy. Both univariate and multivariate Cox regression analyses showed that the patients receiving lobectomy had better OS [hazards ratio (HR) = 1.197, 95% confidence interval (CI) (1.066, 1.343), P < 0.001] than those receiving segmentectomy. However, multivariate analysis showed that there was no significant difference in LCSS between lobectomy and segmentectomy [HR = 1.172, 95% CI (0.963, 1.427), P = 0.114]. Meanwhile, subgroup analyses showed that lobectomy rather than segmentectomy was associated with better OS [HR = 1.278, 95% CI (1.075, 1.520) P = 0.006] and LCSS [HR = 1.118, 95% CI (1.005, 1.280), P = 0.047] for patients with a tumor size (TS) of ≤ 40 and >30 mm, while for patients with a TS of ≤ 30 mm, lobectomy yielded similar OS [TS ≤ 20 mm: HR = 1.068, 95% CI (0.853, 1.336), P = 0.566; TS > 20 mm and ≤ 30 mm: HR = 1.195, 95% CI (0.961, 1.487), P = 0.109] and LCSS [TS ≤ 20 mm: HR = 1.029, 95% CI: (0.682, 1.552), P = 0.893; TS > 20 and ≤ 30 mm: HR = 1.144, 95% CI (0.795, 1.645), P = 0.469] to that of segmentectomy.

Conclusion: Segmentectomy achieved equivalent OS and LCSS in stage IB NSCLC patients with TS ≤ 30 mm compared with lobectomy. Lobectomy showed better OS and LCSS than segmentectomy for patients with a TS of >30 and ≤ 40 mm. Segmentectomy may be acceptable in patients with an older age and a smaller TS.

Comparison of prognostic impact of lymphovascular invasion in stage IA non-small cell lung cancer after lobectomy versus sublobar resection: A propensity score-matched analysis

OBJECTIVES

Lymphovascular invasion (LVI) is a well-known poor prognostic factor after lobectomy for non-small cell lung cancer. However, the prognostic effect of LVI in patients who undergo sublobar resection has not been fully evaluated. Thus, we compared the prognostic impact of LVI in stage IA patients who underwent lobectomy or sublobar resection.

MATERIALS AND METHODS

We retrospectively reviewed the data from patients with stage IA NSCLC who underwent surgical resection between 2007 and 2016. The prognostic impact of LVI was calculated by the Cox proportional hazard regression model. To adjust for the differences in confounding variables between LVI-positive and LVI-negative patients, propensity score matching (PSM) was carried out in patients who underwent lobectomy or sublobar resection.

RESULTS

Among the stage IA NSCLC patients (n = 2134), 184 (8.6%) had been diagnosed with LVI, of whom 144 (8.9%) were in the lobectomy group (n = 1614) and 40 (7.7%) were in the sublobar resection group (n = 520). In multivariable analysis, LVI was a significant risk factor for both overall survival (OS) (hazard ratio [HR], 2.03; 95% confidence interval [CI], 1.39-2.96; p < 0.001) and recurrence-free survival (RFS) (HR, 2.31; 95% CI, 1.68-3.17; p < 0.001). After PSM, the prognostic impact of LVI was greater in the sublobar resection group (HR = 4.93 and 4.25 for OS and RFS, respectively) than in the lobectomy group (HR = 1.77 and 2.51 for OS and RFS, respectively).

CONCLUSIONS

The presence of LVI was significantly associated with worse OS and RFS in stage IA NSCLC patients. The prognostic impact of LVI was more pronounced in the sublobar resection group than in the lobectomy group.

Oncologic Outcomes of Surgery Versus SBRT for Non-Small-Cell Lung Carcinoma: A Systematic Review and Meta-analysis

BACKGROUND

The optimal treatment of stage I non-small-cell lung carcinoma is subject to debate. The aim of this study was to compare overall survival and oncologic outcomes of lobar resection (LR), sublobar resection (SR), and stereotactic body radiotherapy (SBRT).

METHODS

A systematic review and meta-analysis of oncologic outcomes of propensity matched comparative and noncomparative cohort studies was performed. Outcomes of interest were overall survival and disease-free survival. The inverse variance method and the random-effects method for meta-analysis were utilized to assess the pooled estimates.

RESULTS

A total of 100 studies with patients treated for clinical stage I non-small-cell lung carcinoma were included. Long-term overall and disease-free survival after LR was superior over SBRT in all comparisons, and for most comparisons, SR was superior to SBRT. Noncomparative studies showed superior long-term overall and disease-free survival for both LR and SR over SBRT. Although the papers were heterogeneous and of low quality, results remained essentially the same throughout a large number of stratifications and sensitivity analyses.

CONCLUSION

Results of this systematic review and meta-analysis showed that LR has superior outcomes compared to SBRT for cI non-small-cell lung carcinoma. New trials are underway evaluating long-term results of SBRT in potentially operable patients.

Time trends and predictors of survival in surgically resected early-stage non-small cell lung cancer patients

BACKGROUND

The improvement in the management of lung cancer have the potential to improve survival in patients undergoing resection for early-stage (stage I and II) non-small cell lung cancer (NSCLC), but few studies have evaluated time trends and identified predictors of overall survival (OS).

METHODS

We identified surgically resected early-stage NSCLC between 1998 and 2016. The 3-year OS (1998-2014) and 5-year OS (1998-2012) rates were calculated for each year. Joinpoint regression was used to calculate annual percentage changes (APC) and to test time trends in OS. Multivariable Cox regression was used to identify predictors of OS.

RESULTS

There was a significant upward trend in the 3-year (1998, 56%; 2014, 83%; APC = 1.8) and 5-year (1998, 47%; 2012, 76%; APC = 3.1) OS. Older age; male sex; history of diabetes, coronary artery disease, and chronic obstructive pulmonary disease; high ASA score; smoking pack-years; high-grade tumor; pneumonectomy; thoracotomy; neoadjuvant therapy; nodal disease; and positive tumor margin were predictors of poor OS.

CONCLUSION

The upward time trend in OS suggests that improved staging, patient selection, and management have conferred a survival benefit in early-stage NSCLC patients. The prediction model of OS could be used to refine selection criteria for resection and improve survival outcomes.

Equivalent Survival Between Lobectomy and Segmentectomy for Clinical Stage IA Lung Cancer

BACKGROUND

The oncologic efficacy of segmentectomy is controversial. We compared long-term survival in clinical stage IA (T1N0) Medicare patients undergoing lobectomy and segmentectomy in The Society of Thoracic Surgeons database.

METHODS

The Society of Thoracic Surgeons General Thoracic Surgery Database was linked to Medicare data in 14,286 lung cancer patients who underwent segmentectomy (n = 1654) or lobectomy (n = 12,632) for clinical stage IA disease from 2002 to 2015. Cox regression was used to create a long-term survival model. Patients were then propensity matched on demographic and clinical variables to derive matched pairs.

RESULTS

In Cox modeling segmentectomy was associated with survival similar to lobectomy in the entire cohort (hazard ratio, 1.04; 95% confidence interval, 0.89-1.20; P = .64) and in the matched subcohort. A subanalysis restricted to the 2009 to 2015 population (n = 11,811), when T1a tumors were specified and positron emission tomography results and mediastinal staging procedures were accurately recorded in the database, also showed that segmentectomy and lobectomy continue to have similar survival (hazard ratio, 1.00; 95% confidence interval, 0.87-1.16). Subanalysis of the pathologic N0 patients demonstrated the same results.

CONCLUSIONS

Lobectomy and segmentectomy for early-stage lung cancer are equally effective treatments with similar survival. Surgeons from The Society of Thoracic Surgeons database appear to be selecting patients appropriately for sublobar procedures.

Surgical Choice for Clinical Stage IA Non-Small Cell Lung Cancer: View From Regional Lymph Node Metastasis

BACKGROUND

We aimed to investigate the pattern of regional lymph node (LN) metastasis of early-stage non-small cell lung cancer (NSCLC) to provide novel rationale for surgical choice (lobectomy, segmentectomy, or wedge resection) for these patients.

METHODS

We retrospectively collected clinical data of patients undergoing lobectomy with systematic mediastinal LN dissection or sampling for cT1N0M0 peripheral NSCLC from January 2015 to December 2018. The regional LN metastasis pattern was analyzed based on tumor size.

RESULTS

We included a total of 354 patients for analysis. The rate of hilar or intrapulmonary LN metastasis was 13.6%. When stratified by tumor size, NSCLC less than or equal to 1 cm had no hilar or intrapulmonary LN metastasis (0%) while NSCLC greater than 2 cm but less than or equal to 3 cm had a significantly high rate of hilar or intrapulmonary LN metastasis (18.4%) and the rates of hilar, interlobar, and peripheral LN metastasis were also relatively high (5.4%, 5.4%, and 12.2%, respectively). NSCLC greater than 1.5 cm but less than or equal to 2 cm also had relatively high rates of hilar (6.5%) and peripheral (18.3%) LN metastasis, while NSCLC greater than 1 cm but less than or equal to 1.5 cm had significantly low rates of hilar or intrapulmonary (2.5%) and peripheral (2.5%) LN metastasis. Radiographic feature and histology were found to be independent predictors of regional LN metastasis.

CONCLUSIONS

The pattern of regional LN metastasis in clinical stage IA peripheral NSCLC was significantly influenced by tumor size, which may provide evidence on surgical choice (lobectomy, segmentectomy, or wedge resection) for these early-stage NSCLC patients based on tumor size.

Lobectomy does not confer survival advantage over segmentectomy for non-small cell lung cancer with unsuspected nodal disease

OBJECTIVE

Conversion to lobectomy is typically performed when positive lymph nodes are found during intentional segmentectomy. Our objective was to evaluate survival after lobectomy and segmentectomy in patients with unsuspected nodal metastases.

METHODS

The National Cancer Database was queried for patients with clinical T1N0, pathological N1/N2 non-small cell lung cancer (NSCLC) who underwent either lobectomy or segmentectomy. Survival differences between the 2 groups were evaluated using a propensity score model. Cox regression analysis was used to evaluate predictors of overall survival, including adjuvant treatment. Statistical analysis was done using SPSS version 21.0 (IBM Corp, Armonk, NY).

RESULTS

Between 2004 and 2015, unsuspected pathological N1 disease for clinical T1N0M0 NSCLC was found in 2.5% (228/9118) and 6.7% (8915/132,604) of patients who underwent segmentectomy and lobectomy, respectively. The incidence of unsuspected pathological N2 disease for clinical T1N0M0 NSCLC was 2.4% (224/9118) after segmentectomy and 3.9% (5192/132,604) after lobectomy. Using propensity matched pairs (227 pairs for N1 and 215 for N2), segmentectomy showed equivalent 5-year survival compared with lobectomy for the N1 group (41.9% vs 44.3%; P = .35), and N2 group (41.6% vs 37.2%; P = .99). In a multivariable model, adjuvant chemotherapy was associated with better survival of patients with unsuspected N1 (hazard ratio, 0.613; 95% confidence interval, 0.536-0.700; P < .001) and N2 (hazard ratio, 0.684; 95% confidence interval, 0.583-0.802; P < .001) nodal metastases.

CONCLUSIONS

Survival is similar between lobectomy and segmentectomy for clinical T1N0 and unsuspected pathological N1/N2 nodal metastases. The use of adjuvant chemotherapy significantly improves survival in patients with lymph node metastasis (N1/N2) independent of the type of anatomic lung resection.

Propensity-Matched Analysis Comparing Survival After Sublobar Resection and Lobectomy for cT1N0 Lung Adenocarcinoma

BACKGROUND

The optimal surgical method for cT1N0 lung adenocarcinoma remains controversial.

OBJECTIVE

The aim of this study was to evaluate the differences in clinical outcomes of sublobar resection and lobectomy for cT1N0 lung adenocarcinoma patients.

METHODS

We included 1035 consecutive patients with cT1N0 lung adenocarcinoma who underwent surgery at our institute from January 2011 to December 2016. The surgical approach, either sublobar resection or lobectomy, was determined at the discretion of each surgeon. A propensity-matched analysis incorporating total tumor diameter, solid component diameter, consolidation-to-tumor (C/T) ratio, and performance status was used to compare the clinical outcomes of the sublobar resection and lobectomy groups.

RESULTS

Sublobar resection and lobectomy were performed for 604 (58.4%; wedge resection/segmentectomy: 470/134) and 431 (41.6%) patients, respectively. Patients in the sublobar resection group had smaller total tumor diameters, smaller solid component diameters, lower C/T ratios, and better performance status. More lymph nodes were dissected in the lobectomy group. Patients in the sublobar resection group had better perioperative outcomes. A multivariable analysis revealed that the solid component diameter and serum carcinoembryonic antigen level are independent risk factors for tumor recurrence. After propensity matching, 284 paired patients in each group were included. No differences in overall survival (OS; p = 0.424) or disease-free survival (DFS; p = 0.296) were noted between the two matched groups.

CONCLUSIONS

Sublobar resection is not inferior to lobectomy regarding both DFS and OS for cT1N0 lung adenocarcinoma patients. Sublobar resection may be a feasible surgical method for cT1N0 lung adenocarcinoma.