Systematic review and meta-analysis of video-assisted thoracoscopic surgery segmentectomy versus lobectomy for stage I non-small cell lung cancer

Machine-Learning-Based Classification Model to Address Diagnostic Challenges in Transbronchial Lung Biopsy

BACKGROUND

When obtaining specimens from pulmonary nodules in TBLB, distinguishing between benign samples and mis-sampling from a tumor presents a challenge. Our objective is to develop a machine-learning-based classifier for TBLB specimens.

METHODS

Three pathologists assessed six pathological findings, including interface bronchitis/bronchiolitis (IB/B), plasma cell infiltration (PLC), eosinophil infiltration (Eo), lymphoid aggregation (Ly), fibroelastosis (FE), and organizing pneumonia (OP), as potential histologic markers to distinguish between benign and malignant conditions. A total of 251 TBLB cases with defined benign and malignant outcomes based on clinical follow-up were collected and a gradient-boosted decision-tree-based machine learning model (XGBoost) was trained and tested on randomly split training and test sets.

RESULTS

Five pathological changes showed independent, mild-to-moderate associations (AUC ranging from 0.58 to 0.75) with benign conditions, with IB/B being the strongest predictor. On the other hand, FE emerged to be the sole indicator of malignant conditions with a mild association (AUC = 0.66). Our model was trained on 200 cases and tested on 51 cases, achieving an AUC of 0.78 for the binary classification of benign vs. malignant on the test set.

CONCLUSION

The machine-learning model developed has the potential to distinguish between benign and malignant conditions in TBLB samples excluding the presence or absence of tumor cells, thereby improving diagnostic accuracy and reducing the burden of repeated sampling procedures for patients.

Segmentectomy versus lobectomy. Which factors are decisive for an optimal oncological outcome?

Low-dose computed tomography is being used for lung cancer screening in high-risk groups. Detecting lung cancer at an early stage improves the chance of optimal treatment and increases overall survival. This article compares segmentectomy vs. lobectomy as surgical options, in the case of stage I non-small cell lung carcinoma, ideally IA. To compare the 2 previously referred strategies, data were collected from articles (40 studies were reviewed), reviews, and systematic analyses in PubMed Central, as well as reviewing recent literature. Segmentectomy could be an equal alternative to lobectomy in early-stage NSCLC (tumour < 2 cm). It could be preferred for patients with a low cardiopulmonary reserve, who struggle to survive a lobectomy. As far as early-stage NSCLC is concerned, anatomic segmentectomy is an acceptable procedure in a selective group of patients. For better tumour and stage classification, a systematic lymph node dissection should be performed.

Surgical resection versus radiotherapy for clinical stage IA lung cancer ≤1 cm in size: A population-based study

OBJECTIVE

With the increasing incidence of stage IA lung cancer ≤1 cm in size, the optimal primary treatment remains to be controversial, and thus, we compared the survival of these patients treated with radiotherapy, wedge resection, segmentectomy, or lobectomy in a large population.

METHODS

We identified patients with stage IA lung cancer ≤1 cm in size between 2004 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database. We compared the overall survival (OS) via Kaplan-Meier analysis and conducted Cox regression analysis via propensity score matching (PSM) method to identify the relative hazard ratio (HR) and difference of OS among these treatments in the subgroup stratified by four variables (age, total number of tumors, pathological grade, and histology).

RESULTS

A total of 5435 patients were included with a median age of 68 years (range, 6-94 years), of which 2131 (39.2%) were male, and 3510 (64.6%) were adenocarcinoma. The 5-year OS rate was 67.1%, 34.5%, 61.6%, 72.1%, and 75.0% for the entire study population, radiotherapy, wedge resection, segmentectomy, and lobectomy, respectively. In PSM analysis, wedge resection and segmentectomy were all superior to radiotherapy (P < 0.001), and segmentectomy was superior to wedge resection (P = 0.043), while segmentectomy was comparable with lobectomy (P = 0.058). In patients with multiple tumors, radiotherapy brought similar survival to surgery (wedge resection versus radiotherapy, P = 0.323; segmentectomy versus radiotherapy, P = 0.170; lobectomy versus radiotherapy, P = 0.796).

CONCLUSIONS

Among stage IA lung cancer with ≤1 cm, segmentectomy and lobectomy were identified as the potential effective treatments, with segmentectomy more preferred, while radiotherapy would be recommended in those with multiple tumors, which requires further verification.

Split-Lobe for Tumor between Left S3 and S4 by Uniportal Video-Assisted Thoracoscopy

Video-assisted thoracoscopic surgery (VATS) segmentectomy is an optimal treatment for malignant pulmonary ground glass nodules (GGNs). However, this surgery is complicated when tumors are located between more than two adjacent segments, although combined subsegmentectomy ensures sufficient margin under uniportal approach. Lobectomy might be inevitable, especially when resecting deep nodules in the central left upper lung lobe. Here, we present cases wherein we performed uniportal VATS (UVATS) resection for GGNs located between borders of left S3 and S4, with three-dimensional reconstruction conducted before surgery. The strategy of resecting central tumors in the left upper lung lobe between left S3 and S4 via UVATS is simple and feasible.

Minimally Invasive Anatomical Segmentectomy versus Lobectomy in Stage IA Non-Small Cell Lung Cancer: A Systematic Review and Meta-Analysis

OBJECTIVE

A systematic review and meta-analysis was performed to assess potential differences in perioperative outcomes and disease-free survival (DFS) and overall survival (OS) of patients with pathological stage IA non-small cell lung cancer (NSCLC) who underwent minimally invasive anatomical segmentectomy or lobectomy.

METHODS

This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic search of EMBASE (through Ovid), MEDLINE (via PubMed), and Cochrane CENTRAL was conducted. Two researchers independently reviewed each eligible study that included patients with stage IA NSCLC who underwent minimally invasive anatomical segmentectomy and lobectomy and compared perioperative and/or survival outcomes of patients.

RESULTS

A total of 887 publications were identified. Of these, 10 articles met our eligibility criteria. A significantly higher number of lymph nodes were harvested in lobectomies. The two groups did not significantly differ in postoperative complication rates, DFS, and OS. Patients who underwent segmentectomy had shorter postoperative hospital stays.

CONCLUSIONS

Minimally invasive lobectomy and segmentectomy showed comparable short-term and long-term outcomes in stage IA NSCLC patients. Postoperative complication rates were similar. Minimally invasive lobectomies are associated with a higher number of harvested lymph nodes, although this did not affect the final staging or the survival outcomes.

Pulmonary function changes after uniportal video-assisted thoracoscopic anatomical lung resection

OBJECTIVE

The superiority of segmentectomy over lobectomy with regard to preservation of pulmonary function is controversial. This study aimed to examine changes in pulmonary function after uniportal video-assisted thoracoscopic surgery (VATS) according to the number of resected segments.

METHODS

We retrospectively reviewed 135 consecutive patients who underwent anatomical lung resection via uniportal VATS from April 2015 to December 2020. Pulmonary function loss was evaluated using forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1). Patients were grouped according to number of resected segments: one-segment (n = 33), two segments (n = 22), three segments (n = 40), four segments (n = 15), and five segments (n = 25).

RESULTS

Clinical characteristics did not significantly differ between groups, except for tumor size. Mean follow-up was 8.96 ± 3.16 months. FVC loss was significantly greater in five-segment resection (10.8%) than one-segment (0.97%, p = 0.008) and two-segment resections (2.44%, p = 0.040). FEV1 loss was significantly greater in five-segment resection (15.02%) than one-segment (3.83%, p < 0.001), two-segment (4.63%, p = 0.001), and three-segment resections (7.63%, p = 0.007). Mean FVC loss and FEV1 loss increased linearly from one-segment resection to five-segment resection. Mean loss in FVC and FEV1 per segment resected was 2.16% and 3.00%, respectively.

CONCLUSIONS

Anatomical lung resection of fewer segments was associated with better preservation of pulmonary function in patients undergoing uniportal VATS, and function loss was approximately 2%-3% per segment resected with linear relationship.

Computed Tomography-Guided Localization and Extended Segmentectomy for Non-Small Cell Lung Cancer

Background: Lung cancer is one of the most devastating cancers. Low-dose computed tomography (LDCT) can detect lung cancer at an early stage of the disease when a minimally invasive surgical procedure using video-assisted thoracoscopic surgery is the best strategy. Herein, we discuss the treatment of deep lung tumors between segments or lesions located near the margin of a segment. Patients and Methods: This was a retrospective study conducted from January 2013 to January 2020 using the National Taiwan University Hospital data bank. We included early-stage non-small cell lung cancer (NSCLC) patients who underwent lung surgery and screened out those who received CT-guided localization for extended segmentectomy. Outcome measurements were safety margin, complication rate, and postoperative course. Results: During the study period, 68 patients with early-stage NSCLC received CT-guided localization followed by extended segmentectomy. The mean surgery time was 92.1 ± 30.3 min, and the mean blood loss was 32.8 mL. Mean drainage time was 2.3 ± 1 days, and the total hospital stay was 4.9 ± 1.1 days. Pathological reports showed tumor-free resection margins >2 cm. Sixty-one patients had adenocarcinoma at stage IA and two patients at stage IB. One patient had squamous cell carcinoma at stage IA. Conclusion: CT-guided localization followed by extended segmentectomy allows lung volume preservation with clean safety margins and good clinical outcomes.

A Method to Identify Intersegmental Planes for Robotic-assisted Anatomic Segmentectomy Without Waiting

Identifying intersegmental planes is considered the key step during segmentectomy. Several techniques, including modified inflation-deflation techniques, target-segment jet ventilation, and infrared-fluorescence-enhanced methods, have been reported for the identification of intersegmental planes. However, limitations of these methods have also been reported. Here, we described an improved collateral ventilation method to identify the inflation-deflation line without waiting and without any auxiliary materials needed during robotic-assisted anatomic segmentectomy. We present this handy technique of identifying the intersegmental planes and comment on its advantages, including decreased operative time and improved clarity of the inflation-deflation line.

Lobectomy versus segmentectomy in patients with stage T (> 2 cm and ≤ 3 cm) N0M0 non-small cell lung cancer: a propensity score matching study

Background

The safety and effectiveness of lung segmentectomy in patients with early non-small cell lung cancer (NSCLC) remains controversial. We have therefore reviewed the clinicopathologic characteristics and survival outcomes of patients treated with lobectomy or segmentectomy for early T (> 2 and ≤ 3 cm) N0M0 NSCLC.

Methods

We obtained data from the Surveillance, Epidemiology, and End Results database for patients who underwent lobectomy or segmentectomy between 2004 and 2015. To reduce bias and imbalances between the treatment groups, propensity score matching analysis was performed. We used Kaplan–Meier curves to estimate overall survival (OS) and lung cancer-specific survival (LCSS). We conducted univariate and multivariate Cox proportional hazards regression analyses to identify independent prognostic factors for OS and cancer-specific survival, and applied the Cox proportional hazards model to create forest plots.

Results

Before matching, both univariate and multivariate Cox regression analyses revealed that patients who underwent lobectomy exhibited better OS (P < 0.001) and LCSS (P = 0.001) than patients who underwent segmentectomy. However, after matching, survival differences between the groups were not significant; OS (P = 0.434) and LCSS (P = 0.593). Regression analyses revealed that age and tumor grade were independent predictors of OS and LCSS (P < 0.05).

Conclusions

Patients with stage T (> 2 and ≤ 3 cm) N0M0 NSCLC undergoing segmentectomy can obtain OS and LCSS similar to those obtained with lobectomy. Further studies are required considering the solid component effects and pathologic tumor types regarding segmentectomies. Additional long-term survival and outcome analyses should be conducted with larger cohorts.

Thoracoscopic segmentectomy versus lobectomy: A propensity score–matched analysis

Objectives

The aim of this study is to compare the postoperative complications, perioperative course, and survival among patients from the multicentric Spanish Video-assisted Thoracic Surgery Group database who received video-assisted thoracic surgery lobectomy or video-assisted thoracic surgery anatomic segmentectomy.

Methods

From December 2016 to March 2018, a total of 2250 patients were collected from 33 centers. Overall analysis (video-assisted thoracic surgery lobectomy = 2070; video-assisted thoracic surgery anatomic segmentectomy = 180) and propensity score–matched adjusted analysis (video-assisted thoracic surgery lobectomy = 97; video-assisted thoracic surgery anatomic segmentectomy = 97) were performed to compare postoperative results. Kaplan–Meier and competing risks method were used to compare survival.

Results

In the overall analysis, video-assisted thoracic surgery anatomic segmentectomy showed a lower incidence of respiratory complications (relative risk, 0.56; confidence interval, 0.37-0.83; P = .002), lower postoperative prolonged air leak (relative risk, 0.42; 95% confidence interval, 0.23-0.78; P = .003), and shorter median postoperative stay (4.8 vs 6.2 days; P = .004) than video-assisted thoracic surgery lobectomy. After propensity score–matched analysis, prolonged air leak remained significantly lower in video-assisted thoracic surgery anatomic segmentectomy (relative risk, 0.33; 95% confidence interval, 0.12-0.89; P = .02). Kaplan–Meier and competing risk curves showed no differences during the 3-year follow-up (median follow-up in months: 24.4; interquartile range, 20.8-28.3) in terms of overall survival (hazard ratio, 0.73; 95% confidence interval, 0.45-1.7; P = .2), tumor progression–related mortality (subdistribution hazard ratio, 0.41; 95% confidence interval, 0.11-1.57; P = .2), and disease-free survival (subdistribution hazard ratio, 0.73; 95% confidence interval, 0.35-1.51; P = .4) between groups.

Conclusions

Video-assisted thoracic surgery segmentectomy showed results similar to lobectomy in terms of postoperative outcomes and midterm survival. In addition, a lower incidence of prolonged air leak was found in patients who underwent video-assisted thoracic surgery anatomic segmentectomy.

Segmentectomy and Wedge Resection for Elderly Patients with Stage I Non-Small Cell Lung Cancer: A Systematic Review and Meta-Analysis

Background: Considerable controversies exist regarding the efficacies of segmentectomy and wedge resection for elderly patients with early-stage non-small cell lung cancer (NSCLC). This systematic review and meta-analysis aimed to solve these issues. Methods: We searched the online databases PubMed, Web of Science, EMBASE, and Cochrane Library to identify eligible studies. Elderly patients were defined as ≥65 years. Early-stage NSCLC was defined as stage I based on TNM systems. The primary endpoints were survival outcomes (overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS)) and recurrence patterns. The second endpoints were perioperative morbidities. The hazard rate (HR) and odds ratio (OR) were effect sizes. Results: Sixteen cohort studies (3140 participants) and four database studies were finally included. Segmentectomy and lobectomy showed no significant difference in OS (cohort studies HR 1.00, p = 0.98; database studies HR 1.07, p = 0.14), CSS (HR 0.91, p = 0.85), or DFS (HR 1.04, p = 0.78) in elderly patients with stage I NSCLC. In contrast, wedge resection showed inferior OS (HR 1.28, p < 0.001), CSS (HR 1.17, p = 0.001) and DFS (HR 1.44, p = 0.042) compared to lobectomy. Segmentectomy also showed comparable local recurrence risk with lobectomy (OR 0.98, p = 0.98), while wedge resection showed increased risk (OR 5.46, p < 0.001). Furthermore, sublobar resections showed a decreased risk of 30/90-day mortality, pneumonia, and leak complications compared to lobectomy. Conclusion: Segmentectomy is promising when applied to elderly patients with stage I NSCLC, while wedge resection should be limited. Randomized controlled trials are warranted to validate these findings.

Effect and feasibility of uniportal thoracoscopic surgery in the treatment of early-stage lung cancer in a primary hospital

BACKGROUND

Thoracoscopic radical lobectomy is a routine procedure for radical surgery of lung cancer. Meanwhile, thoracoscopic surgery has been gradually transformed from assisted small incision and multiport thoracoscopic radical surgery to uniportal thoracoscopic surgery for treatment of early-stage lung cancers. However, there are still controversies regarding the efficacy and feasibility of 2 surgical methods. The purpose of this study is to investigate the effect and feasibility of uniportal thoracoscopic surgery for treatment of early-stage lung cancer in a primary hospital.

METHODS

Clinical data of 142 patients with early-stage lung cancer were retrospectively chosen in the period from September 2019 to March 2021 in our hospital and divided into 2 groups: a control group (66 patients) with 3-port thoracoscopic radical surgery and an experimental group (76 patients) with uniportal thoracoscopic radical surgery. The baseline clinical data, perioperative clinical data, and lymph node dissection of 2 groups were compared.

RESULTS

There was no significant difference in baseline general clinical data between 2 groups (P>0.05), and no significant difference in the incidence of postoperative complications, conversion rate, or operation time between 2 groups (P>0.05). The intraoperative blood loss volume, postoperative chest drainage volume, postoperative hospitalization time, and postoperative catheter time of experimental group were significantly lower than those of control group (P<0.05). There was no significant difference in the total number of lymph node dissection stations and lymph node dissections, the number of N2 lymph node dissection stations, or N2 lymph node dissections between 2 groups (P>0.05). There was also no significant difference in the number of left and right lymph node dissection stations between 2 groups (P>0.05).

CONCLUSIONS

Compared with 3-port thoracoscopic radical surgery, uniportal thoracoscopic radical surgery in the treatment of patients with early-stage lung cancer provides the same effect of lymph node dissection and has advantages in reducing surgical trauma and accelerating postoperative rehabilitation, popularizing for use in primary hospitals.

A narrative review of invasive diagnostics and treatment of early lung cancer

The diagnosis and treatment of early-stage lung cancer remains a clinical challenge. The broadening implementation of lung cancer screening has resulted in positive findings in numerous patients that are mostly non-malignant. Many other patients have indeterminate nodules that are difficult to assess through simple observation. The critical interpretation of such screening results remains a challenge for radiologists and multidisciplinary teams involved in screening for lung cancer. The evaluation and diagnosis of each participant suspected for malignancy should be based on the basic clinical principles such as a carefully collected medical history, physical examination, and detailed analysis of all imaging tests performed. Indeed, the decision to go ahead with more invasive diagnostics requires consideration of the both the risks and benefits, with reflection upon the complete clinical and radiological picture. Although transthoracic needle aspiration biopsy remains the first-choice method of diagnosis, several newer technologies have slowly begun to emerge as potential replacements. The guiding strategy for method selection is to choose the least harmful approach that offers the most relevant potential insights. Transthoracic biopsy is an effective method that allows the collection of cytological and tissue material from small, peripheral tumors, but it carries a moderate risk of complications. Bronchofiberoscopy, especially in combination with electromagnetic navigation, fluoroscopy or radial EBUS, also allows effective diagnosis of the peripheral pulmonary nodules. One of the most important diagnostic methods is the EBUS examination, which allows determining of staging in addition to diagnosis. Anatomical lung lobe resection and lymphadenectomy or sampling of the hilar and mediastinal lymph nodes is currently the treatment of choice for patients with stage I and II non-small cell lung cancer (NSCLC), but sublobar resections are recommended when a patient has limited pulmonary function or other significant comorbidities. Notably, several studies have highlighted the potential utility of more limited resections in small malignant lesions less than 2cm in diameter, with pure AIS histology, when more than 50% of the diameter of pulmonary nodule has ground-glass opacity (GGO) attenuation on CT, or long volume doubling time (VDT). Videothoracoscopy is the preferred surgical approach for resection of early-stage lung cancer. Patients who are not candidates for surgery or do not agree to surgery can be offered radical radiotherapy. Stereotactic body radiation therapy (SBRT) is a type of radical radiotherapy with proven effectiveness, a high rate of local control and an acceptable risk of the development of later complications. Future trials are expected to define the role of SBRT in the treatment of early lung cancer in healthy subjects.

Prognosis of segmentectomy in the treatment of stage IA non-small cell lung cancer

With improvements in detection technology, increasing numbers of patients with non-small cell lung cancer (NSCLC) are being diagnosed at an early stage. In order to treat the illness with minimal invasion and preserve lung function to the greatest possible extent, there has been an increasing tendency towards treating early-stage NSCLC by segmentectomy. However, questions remain regarding whether patients may benefit from this procedure considering the surgical and oncological outcomes. Whether adequate margin distance and lymph node dissection may be achieved is one of the most important issues associated with this procedure. The present study reviews the prognosis of segmentectomy in the treatment of stage IA NSCLC.

Predictive value of radiological features on spread through air space in stage cIA lung adenocarcinoma

Background

Spread through air space (STAS) is a risk factor for disease recurrence in patients with stage IA lung adenocarcinoma (LUAD) who undergo limited resection. Preoperative prediction of STAS could help intraoperative surgical decision-making in small LUAD patients. The aim of the study was to evaluate the predictive value of radiological features on STAS in stage cIA LUAD.

Methods

A case-control study was designed through retrospective analysis of the radiological features of patients who underwent curative surgery for LUAD with a clinical tumor size ≤3 cm. Univariable and multivariable analyses were used to identify the independent risk factors for STAS. The predicted probability of STAS was calculated by a specific formula. Receiver operating characteristic (ROC) curves were used to determine a cut-off value with appropriate specificity while maintaining high sensitivity for STAS positivity.

Results

STAS was frequently observed in acinar predominant (P<0.001), micropapillary predominant (P<0.001) and solid predominant (P<0.001) tumors and was significantly associated with larger pT size (P<0.001), presence of micropapillary component (P<0.001), lymphovascular invasion (LVI) (P<0.001), visceral pleura invasion (VPI) (P<0.001), both N1 and N2 lymph node metastasis (P<0.001) and ALK rearrangement (P<0.001). STAS-positivity was significantly associated with the presence of cavitation (P=0.047), lobulation (P=0.009), air bronchogram (P<0.001), and vascular convergence (P=0.016) and was also associated with greater maximum tumor diameter (P<0.001), maximum solid component diameter (P<0.001), maximum tumor area (P<0.001), consolidation/tumor ratio (CTR) (P<0.001), tumor disappearance ratio (TDR) (P<0.001) and computed tomography (CT) value (P<0.001). Multivariable analysis showed that STAS was associated with air bronchogram (P=0.042), maximum tumor diameter (P=0.015), maximum solid component diameter (P=0.022) and CTR (P<0.001). The ROC curve showed that the area under the curve (AUC) was 0.726 in the model for predicting STAS, with a sensitivity and specificity of 95.2% and 36.8%, respectively.

Conclusions

STAS-positive LUAD was associated with air bronchogram, maximum tumor diameter, maximum solid component diameter and CTR. These radiological features could predict STAS with excellent sensitivity but inferior specificity.

Perioperative outcomes of segmentectomies versus lobectomies in high-risk patients: an ESTS database analysis

OBJECTIVES

We queried the European Society of Thoracic Surgeons (ESTS) database with the aim to assess cardiopulmonary morbidity and 30-day mortality of segmentectomies and lobectomies in patients with a Eurolung-predicted mortality above the upper interquartile and classified as high risk.

METHODS

A total of 61 492 patients registered in the ESTS database (2007-2018) and submitted to lobectomy (55 353) or segmentectomy (6139) were divided into high risk or low risk according to a Eurolung-predicted mortality cut-off of 2.5% (corresponding in our population to the upper interquartile). Predicted versus observed mortalities were compared within each type of operation by using binomial test of proportion. Observed morbidity and mortality rates were compared between the 2 procedures using the χ2 test.

RESULTS

A total of 14 007 lobectomies and 1251 segmentectomies were classified as high risk. In the high-risk group, the cardiopulmonary morbidity and 30-day mortality rates observed in segmentectomies were lower than in lobectomies (morbidity: 12% vs 17%, P < 0.0001; mortality: 2.4% vs 3.7%, P = 0.018). In segmentectomy patients, the observed mortality rate was lower than the Eurolung-predicted one (2.4% vs 3.8%, P = 0.009), while in the lobectomy patients, there was no difference between observed and predicted mortality (3.7% vs 3.8%, P = 0.9). In the low-risk group, the cardiopulmonary morbidity and 30-day mortality rates observed in segmentectomies were lower than in lobectomies (morbidity: 4.5% vs 7.8%, P < 0.0001; mortality: 0.6% vs 1.0%, P = 0.01). In segmentectomy patients, the observed mortality rate was lower than the Eurolung-predicted one (0.6% vs 1.0%, P = 0.0003), while in the lobectomy patients, there was no difference between observed and predicted mortality (1.0% vs 1.1%, P = 0.06).

CONCLUSIONS

Segmentectomy was found associated with a 0.65 relative risk of mortality rate compared to lobectomy in patients deemed at higher surgical risk.