IA Non-small Cell Lung Cancer Research Articles

A comparative analysis of the results of video-assisted thoracoscopic lobectomies and segmentectomies in patients with stage IA non-small cell lung cancer

Objective. To improve the results of surgical treatment of patients with stage IA NSCLC requiring thoracoscopic anatomical resections.Material and methods. One surgical team performed 132 thoracoscopic lobectomies and segmentectomies in one hospital between 2010 and 2020. This study was consecutive, non-randomized and retrospective.Patients after thoracoscopic lobectomies and segmentectomies for stage IA NSCLC were compared. Additionally, an analysis was performed in 4 subgroups of patients: lobectomy (n=45) and segmentectomy (n=21) with a tumor size up to 2 cm; lobectomy (n=55) and segmentectomy (n=11) with a tumor size from 2 to 3 cm.Results. The comparison groups are comparable in main clinical parameters. There was no mortality in both groups. There were no differences in the postoperative hospital day (6.0 and 6.2 days, p=0.58), the number of removed lymph nodes (9.2 and 9.9, p=0.52) and the percentage of complications (15.6% and 21.9%, p=0.75) when comparing segmentectomies and lobectomies.Differences in the groups were revealed in the length of the machine stitch: in lobectomy — 218.5 mm, in segmentectomy — 309.8 mm (p=0.0001). This pattern was the same in the subgroup analysis. In patients with a tumor from 2 to 3 cm, when removing a segment, the size of the mini-access was smaller than during lobectomy (3.3 cm and 4.0 cm, p=0.0087), and the persistent air leak was longer (6.8 and 2.9 days, p=0.0332).When analyzing long-term outcomes, no significant differences were found either in both group and subgroup analysis; however, there was a tendency towards an increase the overall five-year survival after segmentectomies compared with lobectomies in patients with tumor size ≤2 cm, while with tumor size from 2 to 3 cm, on the contrary, the best long-term results were found in patients operated on with thoracoscopic lobectomy.Conclusion. Thoracoscopic lobectomy and segmentectomy are safe and effective for stage IA NSCLC; the short-term outcomes of surgical treatment of patients with stage IA NSCLC after thoracoscopic lob- and segmentectomies with tumor size ≤2 cm are not significantly different; in patients with the tumor size from 2 to 3 cm, the persistent air leak after segmentectomies was significantly higher than after lobectomies (p=0.033); when evaluating long-term outcomes, no significant differences were found between the study groups and subgroups.

MA03.07 Outcomes of Older Patients in CALGB 140503 (Alliance): Lobar vs Sublobar Resection for Peripheral Stage IA Non-Small Cell Lung Cancer

MA03.07 Outcomes of Older Patients in CALGB 140503 (Alliance): Lobar vs Sublobar Resection for Peripheral Stage IA Non-Small Cell Lung Cancer

EP.07B.08 The Treatment Outcome of SBRT and Sublobar Resection for Vulnerable Elderly Patients with Stage IA Non-Small Cell Lung Cancer

EP.07B.08 The Treatment Outcome of SBRT and Sublobar Resection for Vulnerable Elderly Patients with Stage IA Non-Small Cell Lung Cancer

Optimizing the fairness of survival prediction models for racial/ethnic subgroups: A study on predicting post-operative survival in stage IA and IB non-small cell lung cancer.

380 Background: The recent surge of utilizing machine learning (ML) to develop prediction models for clinical decision-making aids is promising. However, these models can demonstrate racial bias due to inequities in real-world training data. In lung cancer, multiple models have been developed to predict prognosis, but none have been optimized to mitigate bias in performance among racial/ethnic subgroups. We developed a ML model to predict five-year survival in Stage 1A-1B non-small cell lung cancer (NSCLC), ensuring fairness on race. Methods: In the National Cancer Database, we identified patients with histopathologically confirmed stage 1A -1B NSCLC who underwent curative intent lobectomy from 2004 – 2017. We split the study cohort into a training and test sets (70%/30%). We trained and compared various ML models to predict 5-year overall survival. Patient demographic, clinical, and disease characteristics were used as input features for the models. To evaluate model fairness, we used the equalized odds ratio (eOR), which compares the true positive and false positive rates across groups; an eOR value of 1 represents equivalent rates across racial groups. We utilized 3 approaches to mitigate model bias and optimize for fairness of the best “naïve” model: grid search, threshold optimizer, and the exponentiated gradient methods. We evaluated model performance before and after bias mitigation using the area under the curve (AUC). Results: 124,298 patients fit our inclusion/exclusion criteria; 87% of patients were White, 8% were Black/African American, 3% Hispanic, and 2% Asian. Eighty percent of patients were diagnosed with stage 1A cancer; 20% had stage 1B cancer. The best naïve ML model, not optimized for fairness on race, had an eOR of 0.25 with an AUC of 0.66 (95% CI 0.65-0.66) overall. This model demonstrated an AUC of 0.65 (0.65-0.66) among white patients, 0.64 (0.62-0.66) among Black patients, 0.64 (0.60-0.68) among Asian patients, and 0.71 (0.68-0.74) among Hispanic patients. The threshold optimizer bias mitigation strategy improved fairness the most while maintaining similar overall performance of AUC 0.65 (0.64-0.66). With this strategy the eOR improved to 0.83 while AUC remained relatively stable across racial subgroups. Conclusions: We developed a ML model to predict 5-year survival in patients undergoing surgery for stage IA-IB NSCLC and employed model bias mitigation strategies that significantly improved model fairness, without diminishing overall performance. These strategies should be considered when developing prediction models for clinical decision making to avoid perpetuating disparities in care due to algorithm bias. Model performance metrics. Equalized Odds Ratio True Positive Rate False Positive Rate AUC Naive model 0.25 0.61 0.30 0.66 Threshold optimizer mitigated model 0.83 0.62 0.32 0.65

Increased lung cancer recurrence following transthoracic needle biopsy.

Computed tomography (CT)-guided transthoracic needle biopsy (TNB) could damage lung structures and may disseminate tumor cells into the airway, blood vessels, and pleural cavity, affecting post-operative outcomes. Several studies have investigated the effects of TNB on the prognosis of patients, but the effects remain unclear. This study aimed to investigate whether TNB increases the risk of recurrence of resected stage IA non-small cell lung cancer (NSCLC). In this retrospective study, we enrolled 1,077 patients with stage IA NSCLC who underwent curative resection from 2010 to 2020. Recurrence risk factors were evaluated using Cox regression analyses. A multiple logistic regression model, including age, sex, smoking history, total tumor size, invasive tumor size, histology, histologic differentiation, lymphatic invasion, vascular invasion, perineural invasion, and the number of harvested lymph nodes (LNs), was used to calculate the propensity score. According to the pre-operative TNB, patients were classified into the no-TNB (n=823) and TNB (n=190) groups. After propensity score matching analysis, 380 patients were included in the no-TNB group (1:2 matching). Multivariable Cox analysis revealed that pre-operative TNB was a negative prognostic factor in patients with surgically resected stage IA NSCLC [hazard ratio (HR), 3.15; 95% confidence interval (CI): 1.49-6.67; P=0.003]. The 5-year locoregional and overall recurrence-free survival (RFS) rates were significantly lower in the TNB group than in the no-TNB group (88.3% vs. 96.8%, P=0.001; and 84.2% vs. 93.7%, P=0.02, respectively). For patients with stage IA NSCLC, pre-operative TNB was a negative prognostic factor for recurrence. Surgical diagnosis and treatment without pre-operative tissue diagnosis may be considered first in patients with clinically early lung cancer.

Preoperative respiratory assessment predicts post-operative survival in stage IA non-small cell lung cancer.

Respiratory impairment can lead to pulmonary complications after surgery; therefore, it should be considered when determining the choice of surgical procedure. Several studies have examined the relationship between preoperative respiratory function and postoperative mortality and morbidity after lung resection; however, there are no indicators for limited surgical procedure selection. The aim of this study was to examine the association between preoperative respiratory function and postoperative early and late complications, recurrence-free survival (RFS), and overall survival (OS) in patients undergoing pulmonary resection for stage I lung cancer. We performed a retrospective analysis of data from 192 patients undergoing pulmonary resection for primary pathological stage IA non-small cell lung cancer (NSCLC) at the Iwakuni Clinical Center in Japan between 2012 and 2015. We reviewed clinicopathological characteristics including preoperative pulmonary function and elucidated the relationship between them and postoperative survival. Obstructive ventilatory impairment was present in 55 patients (28.6%), and restrictive ventilatory impairment was present in 31 patients (16.1%). Seven patients (3.6%) had both ventilatory impairment. Obstructive ventilatory impairment did not affect the 5-year RFS (P=0.08) or OS (P=0.21). However, restrictive ventilatory impairment reduced the 5-year RFS (P=0.002) and OS (P=0.009). The rates of early and late complications were not significantly different based on the preoperative respiratory function. In patients with preoperative restrictive ventilatory impairment in whom lobectomy or segmentectomy cannot be performed, careful consideration is needed for surgical indications.

Utility of FDG PET-CT in CT Stage IA non-small cell lung cancer: The New Zealand Te Whatu Ora Northern region experience.

Our objective was to investigate the utility of fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) in assessing CT Stage 1A non-small cell lung cancer (NSCLC) in patients under consideration for curative treatment. Performing FDG PET-CT in these patients may lead to unnecessary delays in treatment if it can be shown to provide no added value. We retrospectively reviewed 735 lesions in 653 patients from the New Zealand Te Whatu Ora Northern region lung cancer database with suspected or pathologically proven Stage 1A NSCLC on CT scan who also underwent FDG PET-CT imaging. We determined how often FDG PET-CT findings upstaged patients and then compared to pathological staging where available. FDG PET-CT provided an overall upstaging rate of 9.7%. Category-specific rates were 0% in Tis, 0.9% in T1mi, 7.4% in T1a, 10% in T1b and 12% in T1c groups. The percentage of lesions upstaged on FDG PET-CT that remained Stage 1A was 100% in T1mi, 100% in T1a, 47.1% in T1b and 40.7% in T1c groups. The P value was statistically significant at 0.004, indicating upstaging beyond Stage 1A was dependent on T category. Our data suggests that FDG PET-CT is indicated for T1b and T1c lesions but is of limited utility in Tis, T1mi and T1a lesions. Adopting a more targeted approach and omitting FDG PET-CT in patients with Tis, T1mi, and T1a lesions may benefit all patients with lung cancer by improving accessibility and treatment timelines.

Is wedge resection equivalent to segmentectomy in pathological stage IA (≤2 cm) non-small cell lung cancers?

Sublobar resection (wedge resection and segmentectomy) has been established as an oncologically equivalent option to lobectomy for early-stage patients with non-small cell lung cancer (NSCLC) ≤ 2 cm. However, the optimal approach of sublobar resection remains subject to debate. In the present study we aimed to compare the oncological outcomes of wedge resection and segmentectomy in these patients. We identified patients with pT1a-bN0M0 NSCLC who underwent wedge resection and segmentectomy from the Surveillance, Epidemiology, and End Results database between 2010 and 2020. A Cox regression model and propensity-score matching (PSM) analysis were used. Overall survival (OS) and lung cancer-specific survival (LCSS) were compared using the Kaplan-Meier method. A total of 4190 patients met our selection criteria, including wedge resection in 3137 and segmentectomy in 1053. Patients undergoing wedge resection were less likely to have total lymph nodes resected (4 vs. 7, p < 0.001). Before PSM, patients undergoing segmentectomy had a higher 5-year OS rate (87.75% vs. 82.72%; p = 0.0023), while exhibiting a similar LCSS rate (93.45% vs. 92.73%; p = 0.32). After PSM, segmentectomy consistently demonstrated significantly better OS and there was no statistically significant difference in LCSS. Analysis of causes of death revealed that a higher incidence of deaths related to other causes among patients undergoing wedge resection compared to those undergoing segmentectomy. Both wedge resection and segmentectomy yield comparable oncological outcomes for patients with NSCLC ≤ 2 cm, although segmentectomy exhibits superior OS due to less death related to other causes.

The Role of Emphysema on Postoperative Prognosis in Early-Stage Nonsmall Cell Lung Cancer

BackgroundEmphysema is generally considered a poor prognostic factor for patients with nonsmall cell lung cancer; however, whether the poor prognosis is due to highly malignant tumors or emphysema itself remains unclear. This study was designed to determine the prognostic value of emphysema in patients with early-stage nonsmall cell lung cancer.MethodsA total of 721 patients with clinical stage IA nonsmall cell lung cancer who underwent complete resection between April 2007 and December 2018 were retrospectively analyzed regarding clinicopathological findings and prognosis related to emphysema.ResultsThe emphysematous and normal lung groups comprised 197 and 524 patients, respectively. Compared with the normal lung group, lymphatic invasion (23.9% vs. 14.1%, P = 0.003), vascular invasion (37.6% vs. 17.2%, P < 0.001), and pleural invasion (18.8% vs. 10.9%, P = 0.006) were observed more frequently in the emphysema group. Additionally, the 5-year overall survival rate was lower (77.1% vs. 91.4%, P < 0.001), and the cumulative incidence of other causes of death was higher in the emphysema group (14.0% vs. 3.50%, P < 0.001). Multivariable Cox regression analysis of overall survival revealed that emphysema (vs. normal lung, hazard ratio 2.02, P = 0.0052), age > 70 years (vs. < 70 years, hazard ratio 4.03, P < 0.001), and SUVmax > 1.8 (vs. ≤ 1.8, hazard ratio 2.20, P = 0.0043) were independent prognostic factors.ConclusionsEarly-stage nonsmall cell lung cancer with emphysema has a tendency for the development of highly malignant tumors. Additionally, emphysema itself may have an impact on poor prognosis.

Postoperative pulmonary function of patients with lung cancer and interstitial lung abnormalities.

We investigated the impact of radiological interstitial lung abnormalities on the postoperative pulmonary functions of patients with non-small cell lung cancer. A total of 1191 patients with clinical stage IA non-small cell lung cancer who underwent lung resections and pulmonary function tests ≥ 6months postoperatively were retrospectively reviewed. Postoperative pulmonary function reduction rates were compared between patients with and without interstitial lung abnormalities and according to the radiological interstitial lung abnormality classifications. Surgical procedures were divided into wedge resection, 1-2 segment resection, and 3-5 segment resection groups. No significant differences in postoperative pulmonary function reduction rates 6months after wedge resection were observed between the interstitial lung abnormality [n = 202] and non-interstitial lung abnormality groups [n = 989] [vital capacity [VC]: 6.82% vs. 5.00%; forced expiratory volume in 1s [FEV1]: 7.05% vs. 7.14%]. After anatomical resection, these values were significantly lower in the interstitial lung abnormality group than in the non-interstitial lung abnormality group [VC: 1-2 segments, 12.50% vs. 9.93%; 3-5 segments, 17.42% vs. 14.23%; FEV1: 1-2 segments: 13.36% vs. 10.27%; 3-5 segments: 17.36% vs. 14.39%]. No significant differences in postoperative pulmonary function reduction rates according to the radiological interstitial lung abnormality classifications were observed. The presence of interstitial lung abnormalities had a minimal effect on postoperative pulmonary functions after wedge resections; however, pulmonary functions significantly worsened after segmentectomy or lobectomy, regardless of the radiological interstitial lung abnormality classification in early-stage non-small cell lung cancer.

Preoperatively predicting survival outcome for clinical stage IA pure-solid non–small cell lung cancer by radiomics-based machine learning

ObjectiveClinical stage IA non–small cell lung cancer (NSCLC) showing a pure-solid appearance on computed tomography is associated with a worse prognosis. This study aimed to develop and validate machine-learning models using preoperative clinical and radiomic features to predict overall survival (OS) in clinical stage IA pure-solid NSCLC. MethodsPatients who underwent lung resection for NSCLC between January 2012 and December 2020 were reviewed. The radiomic features were extracted from the intratumoral and peritumoral regions on computed tomography. The machine-learning models were developed using random survival forest and eXtreme Gradient Boosting (XGBoost) algorithms, whereas the Cox regression model was set as a benchmark. Model performance was assessed using the integrated time-dependent area under the curve (iAUC) and validated by 5-fold cross-validation. ResultsIn total, 642 patients with clinical stage IA pure-solid NSCLC were included. Among 3748 radiomic and 34 preoperative clinical features, 42 features were selected. Both machine-learning models outperformed the Cox regression model (iAUC, 0.753; 95% confidence interval [CI], 0.629-0.829). The XGBoost model showed a better performance (iAUC, 0.832; 95% CI, 0.779-0.880) than the random survival forest model (iAUC, 0.795; 95% CI, 0.734-0.856). The XGBoost model showed an excellent survival stratification performance with a significant OS difference among the low-risk (5-year OS, 100.0%), moderate low-risk (5-year OS, 88.5%), moderate high-risk (5-year OS, 75.6%), and high-risk (5-year OS, 41.7%) groups (P < .0001). ConclusionsA radiomics-based machine-learning model can preoperatively and accurately predict OS and improve survival stratification in clinical stage IA pure-solid NSCLC.

Treatment strategies for stage IA non-small cell lung cancer: A SEER-based population study.

There are various therapeutic methods for treating stage IA (T1N0M0) non-small cell lung cancer (NSCLC), but no studies have systematically assessed multiple treatments to determine the most effective therapy. Stage IA NSCLC patient data collected between 2004 and 2018 were gathered from the Surveillance, Epidemiology, and End Results (SEER) database. Treatment modalities included observation, chemotherapy alone (CA), radiation alone (RA), radiation+chemotherapy (RC), surgery alone (SA), surgery+chemotherapy (SC), surgery+radiation (SR) and surgery+radiation+chemotherapy (SRC). Comparisons were made of overall survival (OS) and lung cancer-specific survival (LCSS) among patients based on different therapeutic methods by survival analysis. Ultimately, 89147 patients with stage IA NSCLC between 2004 and 2018 were enrolled in this study. The order of multiple treatment modalities based on the hazard ratio (HR) for OS for the entire cohort revealed the following results: SA (HR: 0.20), SC (HR: 0.25), SR (HR: 0.42), SRC (HR: 0.46), RA (HR: 0.56), RC (HR: 0.72), CA (HR: 0.91) (P<0.001), and observation (HR: Ref). The SA group had the best OS and LCSS, and similar results were found in most subgroup analyses (all P<0.001). The order of surgical modalities based on the HR for OS for the entire cohort revealed the following results: lobectomy (HR: 0.32), segmentectomy (HR: 0.41), wedge resection (HR: 0.52) and local tumor destruction (HR: Ref). Lobectomy had the best effects on OS and LCSS, and similar results were found in all subgroup analyses (all P<0.001). SA appeared to be the optimal treatment modality for patients with stage IA NSCLC, and lobectomy was associated with the best prognosis. There may be some indication and selection bias in our study, and the results of this study should be confirmed in a prospective study.

No prognostic impact of staging bone scan in patients with stage IA non-small cell lung cancer.

To investigate the survival benefit of preoperative bone scan in asymptomatic patients with early-stage non-small cell lung cancer (NSCLC). This retrospective study included patients with radical resection for stage T1N0M0 NSCLC between March 2013 and December 2018. During postoperative follow-up, we monitored patient survival and the development of bone metastasis. We compared overall survival, bone metastasis-free survival, and recurrence-free survival in patients with or without preoperative bone scan. Propensity score matching and inverse probability of treatment weighting were used to minimize election bias. A total of 868 patients (58.19 ± 9.69years; 415 men) were included in the study. Of 87.7% (761 of 868) underwent preoperative bone scan. In the multivariable analyses, bone scan did not improve overall survival (hazard ratio [HR] 1.49; 95% confidence intervals [CI] 0.91-2.42; p = 0.113), bone metastasis-free survival (HR 1.18; 95% CI 0.73-1.90; p = 0.551), and recurrence-free survival (HR 0.89; 95% CI 0.58-1.39; p = 0.618). Similar results were obtained after propensity score matching (overall survival [HR 1.28; 95% CI 0.74-2.23; p = 0.379], bone metastasis-free survival [HR 1.00; 95% CI 0.58-1.72; p = 0.997], and recurrence-free survival [HR 0.76; 95% CI 0.46-1.24; p = 0.270]) and inverse probability of treatment weighting. There were no significant differences in overall survival, bone metastasis-free survival, and recurrence-free survival between asymptomatic patients with clinical stage IA NSCLC with or without preoperative bone scan.

Preoperative nomogram for predicting spread through air spaces in clinical-stage IA non-small cell lung cancer using 18F-fluorodeoxyglucose positron emission tomography/computed tomography

PurposeThis study aims to assess the predictive value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) radiological features and the maximum standardized uptake value (SUVmax) in determining the presence of spread through air spaces (STAS) in clinical-stage IA non-small cell lung cancer (NSCLC).MethodsA retrospective analysis was conducted on 180 cases of NSCLC with postoperative pathological assessment of STAS status, spanning from September 2019 to September 2023. Of these, 116 cases from hospital one comprised the training set, while 64 cases from hospital two formed the testing set. The clinical information, tumor SUVmax, and 13 related CT features were analyzed. Subgroup analysis was carried out based on tumor density type. In the training set, univariable and multivariable logistic regression analyses were employed to identify the most significant variables. A multivariable logistic regression model was constructed and the corresponding nomogram was developed to predict STAS in NSCLC, and its diagnostic efficacy was evaluated in the testing set.ResultsSUVmax, consolidation-to-tumor ratio (CTR), and lobulation sign emerged as the best combination of variables for predicting STAS in NSCLC. Among these, SUVmax and CTR were identified as independent predictors for STAS prediction. The constructed prediction model demonstrated area under the curve (AUC) values of 0.796 and 0.821 in the training and testing sets, respectively. Subgroup analysis revealed a 2.69 times higher STAS-positive rate in solid nodules compared to part-solid nodules. SUVmax was an independent predictor for predicting STAS in solid nodular NSCLC, while CTR and an emphysema background were independent predictors for STAS in part-solid nodular NSCLC.ConclusionOur nomogram based on preoperative 18F-FDG PET/CT radiological features and SUVmax effectively predicts STAS status in clinical-stage IA NSCLC. Furthermore, our study highlights that metabolic parameters and CT variables associated with STAS differ between solid and part-solid nodular NSCLC.

BPI24-013: Microwave Ablation Versus Resection Versus Stereotactic Body Radiation Therapy of Stage IA Non-Small Cell Lung Cancer in US Veterans.

BPI24-013: Microwave Ablation Versus Resection Versus Stereotactic Body Radiation Therapy of Stage IA Non-Small Cell Lung Cancer in US Veterans.

Wedge resection, segmentectomy, and lobectomy: oncologic outcomes based on extent of surgical resection for ≤2 cm stage IA non-small cell lung cancer.

Long-standing controversy has existed over whether sublobar resection is an adequate oncological procedure for clinical stage IA non-small cell lung cancer (NSCLC) ≤2 cm, despite the recent randomized trial reports of Japanese Clinical Oncology Group (JCOG) 0802 and Cancer and Leukemia Group B (CALGB) 140503 demonstrating non-inferior outcomes with sublobar resection compared to lobectomy. As practice patterns shift, we sought to compare oncologic outcomes in patients with these early-stage tumors after wedge resection, segmentectomy, or lobectomy in a contemporary, real-world, cohort. A retrospective review of a prospectively maintained database from a single institution was conducted from 2011 to 2020 to identify all patients with clinically staged IA1 or IA2 NSCLC (tumors ≤2 cm with no nodal involvement). The primary outcomes of interest were overall survival (OS) and disease-free survival (DFS), with secondary outcomes of lung cancer-specific survival (LCSS), recurrence patterns, and perioperative morbidity and mortality. A total of 480 patients were identified; 93 (19.4%) patients underwent wedge resection, 90 (18.7%) received segmentectomy, and 297 (61.9%) underwent lobectomy. Patients who underwent wedge resection had worse Eastern Cooperative Oncology Group (ECOG) performance status (23.7% ECOG 1 or 2 vs. 5.6% among segmentectomy and 5.4% among lobectomy, P<0.05). Both wedge resection and segmentectomy patients had lower preoperative mean percentage of predicted forced expiratory volume in one second (%FEV1) compared to the lobectomy group (81.8% and 82.6% vs. 89.6%, P=0.002), a higher proportion of patients with chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD), and a higher Charlson Comorbidity Index. There were no statistically significant differences in 5-year OS, DFS, or LCSS between groups: 90%, 61%, 78% for wedge resections compared with 85%, 75%, 86% for segmentectomy, and 87%, 77%, 87% for lobectomy, respectively. Recurrence was observed in 17 patients who underwent wedge resection (18.3%, 8 local, 9 distant), 12 patients who received segmentectomy (13.4%, 6 local, 6 distant), and 38 patients who underwent lobectomy (12.8%, 11 local, 27 distant), which was not significantly different (P=0.36). Patients with inferior performance status or lower baseline pulmonary function are more likely to receive wedge resection for clinical stage IA NSCLC ≤2 cm in size. For these small tumors, lobectomy, segmentectomy, and wedge resection provide comparable oncologic outcomes.

Abstract No. 84 ▪ Featured Abstract Microwave Ablation versus Surgical Resection versus Stereotactic Body Radiation Therapy of Stage IA Non-small Cell Lung Cancer in US Veterans

Abstract No. 84 ▪ Featured Abstract Microwave Ablation versus Surgical Resection versus Stereotactic Body Radiation Therapy of Stage IA Non-small Cell Lung Cancer in US Veterans

Effects of IFN-γ on the immunological microenvironment and TAM polarity in stage IA non-small cell lung cancer and its mechanisms

ObjectiveTo investigate the effect of interferon-γ (IFN-γ) on the immune microenvironment and the polarity of tumor-associated macrophages (TAMs) in stage IA non-small cell lung cancer (NSCLC) and its mechanisms.MethodsHuman non-small cell lung cancer A549 cells were treated with a series of IFN-γ concentrations (0, 50, 100, 150, 200, 250, and 300 ng/mL). Tumor tissues from patients with stage IA NSCLC were cultured using the air–liquid interface culture technique to establish a tumor microenvironment (TME) organ model. The NSCLC model was constructed by subcutaneously embedding small tumor pieces into the back of nonobese diabetic severe combined immune deficiency (NOD SCID) mice. The size and weight of the tumors were recorded, and the tumor volume was calculated. CCK-8 assays were used to investigate cell proliferation, flow cytometry and TUNEL staining were used to evaluate cell apoptosis, colony formation was investigated by cloning experiments, and cell invasion and migration were evaluated by Transwell assays and scratch tests. The expression of apoptosis-related proteins (Bax, Bcl-2 and C-caspase 3), M2 polarization-related markers (CD163, CD206 and IDO1), and marker proteins of cytotoxic T cells and helper T cells (CD8 and CD4) was detected by Western blot. The expression of Ki-67 and IDO1 was detected by immunohistochemistry, and the levels of IL-6, IL-10, IL-13 and TNF-α were measured by ELISA. The expression of CD68 was measured by RT‒qPCR, and the phagocytosis of TAMs was evaluated by a Cell Trace CFSE kit and cell probe staining.ResultsThe proliferation activity of A549 cells increased with increasing IFN-γ concentration and peaked when the concentration reached 200 ng/mL, and the proliferation activity of A549 cells was suppressed thereafter. After treatment with 200 ng/mL IFN-γ, the apoptosis rate of cells decreased, the number of cell colonies increased, the invasion and migration of cells were promoted, the expression of Bax and C-caspase 3 was downregulated, and the expression of Bcl-2 was upregulated in cells and the TME model. In the TME model, CD163, CD206, IDO1 and Ki-67 were upregulated, CD8 and CD4 were downregulated, apoptosis was reduced, the levels of IL-6 and TNF-α were decreased, and the levels of IL-10 and IL-13 were increased. IL-4 induced TAMs to express CD163 and CD206, reduced the levels of IL-6 and TNF-α, increased the levels of IL-10 and IL-13, and weakened the phagocytic function of TAMs. IFN-γ treatment further enhanced the effect of IL-4 and enhanced the viability of A549 cells. IDO1 decreased the viability of T cells and NK cells, while suppressing the effect of IFN-γ. In mice, compared with NSCLC mice, the tumor volume and weight of the IFN-γ group were increased, the expression of CD163, CD206, IDO1, Ki-67 and Bcl-2 in tumor tissue was upregulated, the expression of Bax and C-caspase 3 was downregulated, and apoptosis was reduced. The levels of IL-6 and TNF-α were decreased, and the levels of IL-10 and IL-13 were increased in the serum of mice.ConclusionIn stage IA NSCLC, a low concentration of IFN-γ promotes the polarization of TAMs to the M2 phenotype in the TME model by upregulating the expression of IDO1, promoting the viability of cancer cells, inhibiting the viability of T cells and NK cells, and thus establishing an immune microenvironment conducive to tumor progression.

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

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

Long-term Survival After Lung Cancer Resection in the National Lung Screening Trial

BackgroundThis study sought to evaluate the long-term survival and causes of death after surgery among patients with pathologic stage IA non-small cell lung cancer (NSCLC) in the National Lung Screening Trial (NLST). MethodsPatients who underwent surgery and who had a diagnosis of pathologic stage IA NSCLC in the NLST were identified for analysis. The 5- and 10-year overall survival and lung cancer–specific survival, stratified by operation type, were evaluated. Among patients who underwent lobectomy, the causes of death and the cumulative incidence of lung cancer death were assessed. ResultsA total of 380 patients (n = 329, 86.6% lobectomy; n = 20, 5.3% segmentectomy; n = 31, 8.1% wedge resection) met inclusion criteria. Median follow-up time from the date of surgery was 7.8 years (interquartile range, 4.8-10.7 years). The 10-year overall survival rate was 58.3% (95% CI, 52.4%-63.8%) for lobectomy, 59.9% (95% CI, 33.2%-78.8%) for segmentectomy, and 45.2% (95% CI, 20.8%-66.9%) for wedge resection. The 10-year lung cancer–specific survival rate was 74.3% (95% CI, 68.6%-79.1%) for lobectomy, 81.3% (95% CI, 51.3%-93.8%) for segmentectomy, and 84.8% (95% CI, 64.0%-94.1%) for wedge resection. Lung cancer was the leading cause of death, accounting for 55.8% of deaths after lobectomy. The 10-year cumulative incidence of lung cancer death after lobectomy was 22.5% (95% CI, 18.3%-27.1%). ConclusionsThe 10-year overall survival rate after lobectomy among patients with pathologic stage IA NSCLC in the NLST was 58%. Lung cancer was the leading cause of death, accounting for more than 55% of deaths.