Survival rates after lobectomy versus sublobar resection for early-stage right middle lobe non-small cell lung cancer

Different nodal upstaging rates and prognoses for patients with clinical T1N0M0 lung adenocarcinoma classified according to the presence of solid components in the lung and mediastinal windows

BACKGROUND

Little is known about the correlation between nodal upstaging and pulmonary nodules classified according to the presence of solid components in the lung and mediastinal windows. This study thus aimed to analyze the risk factors of nodal upstaging and prognosis based on different imaging features, clinical characteristics, and pathological results from patients with clinical stage T1N0M0 lung adenocarcinoma.

METHODS

A total of 340 patients between January 2016 and June 2017 were selected from the Affiliated Hospital of Qingdao University database. Imaging features, clinical characteristics, and pathological results were collected for survival and analysis of nodal upstaging risk factors. We used logistic regression models to identify important metastatic risk factors for nodal upstaging. Survival rates were calculated using Kaplan-Meier (KM) survival curves and compared with the log-rank test. Significant prognostic risk factors were identified using the Cox proportional hazards model.

RESULTS

A total of 340 patients, with an average age of 64.89 (±8.775) years, were enrolled. Among them, nonnodal upstaging occurred both in 77 (22.6%) patients with pure ground-glass nodules (pGGNs) and in 30 (8.8%) patients with heterogenous ground-glass nodules (hGGNs). Compared to the 92 (27.1%) patients with real part-solid nodules (rPSNs), the 141 (41.5%) patients with solid nodules were significantly different in terms of in nodal upstaging (P<0.001). Moreover, preoperative carcinoembryonic antigen (CEA) level >3.4 µg/L [odds ratio (OR): 2.931; 95% confidence interval (CI): 1.511-5.688; P=0.001], imaging tumor size >18.3 mm (OR, 3.482; 95% CI: 1.609-7.535; P=0.002), and consolidation tumor ratio (CTR) >0.788 (OR 8.791; 95% CI: 3.570-21.651; P<0.001) were independent risk factors for nodal upstaging. The KM survival curve results showed that patients with pGGNs and those with hGGNs had a much better 5-year disease-free survival (DFS) and 5-year overall survival (OS) than did those with rPSNs and those with solid nodules (DFS: 98.7% vs. 100% vs. 81.4% vs. 73.7%, P<0.001; OS: 97.4% vs. 100% vs. 90.2% vs. 83.7%, P=0.003). In the multivariate Cox regression analysis of patients with rPSNs and solid nodules, tumor location and pathological lymph node grade were found to be independent risk factors for DFS and OS.

CONCLUSIONS

Patients with pGGNs and those with hGGNs were more likely to be free of nodal upstaging and had better prognosis than did those with clinical stage IA rPSNs and solid nodules. The patients with pGGNs or hGGNs with preoperative CEA level <3.4 µg/L, imaging tumor size <18.3 mm, and CTR <0.788 can choose systematic lymph node sampling (SLNS) or decline lymph node dissection to avoid postoperative complications.

Prediction of Distant Metastases After Stereotactic Body Radiation Therapy for Early Stage NSCLC: Development and External Validation of a Multi-Institutional Model

INTRODUCTION

Distant metastases (DMs) are the primary driver of mortality for patients with early stage NSCLC receiving stereotactic body radiation therapy (SBRT), yet patient-level risk is difficult to predict. We developed and validated a model to predict individualized risk of DM in this population.

METHODS

We used a multi-institutional database of 1280 patients with cT1-3N0M0 NSCLC treated with SBRT from 2006 to 2015 for model development and internal validation. A Fine and Gray (FG) regression model was built to predict 1-year DM risk and compared with a random survival forests model. The higher performing model was evaluated on an external data set of 130 patients from a separate institution. Discriminatory performance was evaluated using the time-dependent area under the curve (AUC). Calibration was assessed graphically and with Brier scores.

RESULTS

The FG model yielded an AUC of 0.71 (95% confidence interval [CI]: 0.57-0.86) compared with the AUC of random survival forest at 0.69 (95% CI: 0.63-0.85) in the internal test set and was selected for further testing. On external validation, the FG model yielded an AUC of 0.70 (95% CI: 0.57-0.83) with good calibration (Brier score: 0.08). The model identified a high-risk patient subgroup with greater 1-year DM rates in the internal test (20.0% [3 of 15] versus 2.9% [7 of 241], p = 0.001) and external validation (21.4% [3 of 15] versus 7.8% [9 of 116], p = 0.095). A model nomogram and online application was made available.

CONCLUSIONS

We developed and externally validated a practical model that predicts DM risk in patients with NSCLC receiving SBRT which may help select patients for systemic therapy.

Comparison of outcomes following lobectomy, segmentectomy, and wedge resection based on pathological subtyping in patients with pN0 invasive lung adenocarcinoma ≤1 cm

PURPOSE

We sought to analyze the prognostic significance of lung adenocarcinoma classification for patients with pathological N0 (pN0) lung invasive adenocarcinomas ≤1 cm who underwent surgical resection and investigate the optimal surgical procedure according to lung adenocarcinoma classification.

METHODS

A total of 1409 consecutive patients with resected pN0 invasive lung adenocarcinoma ≤1 cm were retrospectively reviewed. Comprehensive histologic subtyping was determined according to IASLC/ATS/ERS lung adenocarcinoma classification. Recurrence-free survival (RFS) and overall survival (OS) were compared between patients receiving lobectomy, segmentectomy, and wedge resection.

RESULTS

RFS and OS favored lobectomy and segmentectomy compared with wedge resection in the entire cohort. Five-year RFS rates were 100%, 98.2%, 97.3%, 77.8%, and 82.8% (p < 0.001) for lepidic, acinar, papillary, micropapillary, and solid predominant subtypes, while 5-year OS rates were 100%, 98.4%, 98.1%, 88.9%, and 96.5% (p < 0.001), respectively. Multivariate analysis showed that adenocarcinoma predominant pathological subtype and CT appearance were independent prognostic factors for RFS, and surgical procedure was independent factor for both RFS and OS. Specifically, wedge resection showed worse survival compared with anatomical resection in patients with papillary, micropapillary, or solid predominant subtypes, whereas in patients with lepidic predominant and acinar predominant subtypes, wedge resection showed comparable RFS with anatomical resection.

CONCLUSIONS

Anatomical resection showed better survival for patients with pN0 invasive lung adenocarcinoma ≤1 cm. For patients with invasive adenocarcinoma ≤1 cm in whom anatomical resection is not feasible, wedge resection could provide similar oncological effect when tumor is lepidic predominant or acinar predominant.

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.

Change in treatment modality and trends in survival among stage I non-small cell lung cancer patients: a population-based study

Background

A number of treatment modalities are available to patients with early non-small cell lung cancer (NSCLC) but there is inconsistency regarding their effects on survival. The associated survival of each treatment modality is crucial for patients in making informed treatment decisions. We aimed to examine the change in treatment modality and trends in survival for patients with stage I NSCLC and assess the association between treatment modality and survival.

Methods

All patients diagnosed with stage I NSCLC in the Canadian province of Ontario between 2007 and 2015 were included in this population-based study. We used a flexible parametric model to estimate the trends in survival rate.

Results

Overall, 11,910 patients were identified of which 7,478 patients (62.8%) received surgical resection and 2,652 (22.3%) radiation only. The proportion of patients who received radiation only increased from 13.2% in 2007 to 28.0% in 2015 (P-for-trend <0.001). Survival increased for all treatment modalities from 2007 to 2015. The increase in 5-year survival was more than 20% for all surgical groups and more than 35% for radiation-only group.

Conclusions

The survival of patients with stage I NSCLC increased for all treatment modalities over the study period, most distinctly in elderly patients, which coincided with a rise in the use of radiation therapy. While surgical resection was associated with the best chance of 5-year survival, radiation therapy is a safe and effective treatment for medically inoperable patients with early disease.

Invasive Staging Procedures Do Not Prevent Nodal Metastases From Being Missed in Stage I Lung Cancer

BACKGROUND

Up to 20% of clinical stage I lung cancer patients harbor lymph node metastases that go undetected (missed) during the clinical staging evaluation. We investigated to what degree the addition of invasive nodal staging procedures to imaging, as currently practiced, prevents radiographically occult nodal metastases from being missed during the clinical staging evaluation.

METHODS

Treatment-naive patients, imaged by positron emission tomography and computed tomography, who underwent lobectomy for clinical stage I lung cancer from 2012 to 2017 in The Society of Thoracic Surgeons General Thoracic Surgery Database were studied. Rates of missed nodal metastases (MNM) (ie, nodal metastases in lobectomy specimens undetected during clinical staging evaluation) were determined. Risk factors were assessed with multivariable modeling.

RESULTS

Of the 30,685 clinical stage I patients identified, 3895 (12.7%) underwent preoperative endobronchial ultrasound and 3341 (10.9%) underwent mediastinoscopy. Invasive staging was more common with tumors > 2 cm (66.4% vs 50.2%, P < .001) and squamous histology (26.9% vs 16.9%, P < .001). MNM were discovered in 14.7% of patients, including 20.1% of patients (95% confidence interval, 18.8%-21.5%) who had undergone endobronchial ultrasound and 18.2% (95% confidence interval, 16.7%-19.6%) who had undergone mediastinoscopy. Hilar nodes were most often "missed" (9.5%). Using cut-points in tumor size, histology, laterality, and age, patients could be stratified into particularly high-risk (25% MNM) and low-risk (6% MNM) cohorts.

CONCLUSIONS

Substantial risk of occult lymph node metastases persists in patients with clinical stage I lung cancer despite negative invasive nodal staging, positron emission tomography, and computed tomography. In the absence of a thorough surgical nodal evaluation, early-stage lung cancer patients are at risk of under-treatment.

Lobectomy versus sub-lobar resection in patients with stage IA right middle lobe non-small cell lung cancer: a propensity score matched analysis

Background

The aim of the present study was to compare the prognostic outcomes of patients with stage IA right middle lobe non-small cell lung cancers (RML NSCLCs) that underwent either lobectomy (LR) or sub-lobar resection (SLR) after 1:1 propensity score matching (PSM).

Methods

Patients with stage IA RML NSCLC were identified from the Surveillance, Epidemiology and End Results (SEER) database from 2005 to 2015. Cox regression analysis was carried out to compare lung cancer specific survival (LCSS) following LR or SLR before and after PSM. Subgroup analysis of LCSS stratified by tumor size (≤1, 1-2, and 2-3 cm) was also performed.

Results

A total of 1,104 patients met the inclusion criteria. One hundred ninety-eight (17.9%) patients underwent SLR, and 906 (82.1%) underwent LR. There were significant differences between patients of LR and SLR groups with regard to the tumor size and the number of examined lymph nodes. After PSM, 147 matched pairs (n=294) were selected. Multivariable cox regression analysis revealed no difference in the LCSS of patients that underwent either LR or SLR before [hazard ratio (HR): 0.881, 95% CI: 0.547-1.422, P=0.605] and after PSM (HR: 0.778, 95% CI: 0.409-1.480, P=0.444). Subgroup analysis revealed no significant difference in LCSS between patients of LR and SLR groups with regard to the tumor size (all P>0.05).

Conclusions

Similar to lymphadenectomy, the prognostic outcomes in patients with stage IA RML NSCLC were comparable between LR and SLR.

Body surface area as a novel risk factor for chylothorax complicating video-assisted thoracoscopic surgery lobectomy for non-small cell lung cancer

Background

The study was conducted to demonstrate the predictive value of body surface area (BSA) for chylothorax complicating video‐assisted thoracoscopic surgery (VATS) lobectomy for non‐small cell lung cancer (NSCLC).

Methods

Large‐scale retrospective analysis was conducted on the data of 1379 patients who underwent VATS lobectomy between January 2014 and October 2017 at our institution. Receiver operating characteristic analysis was conducted to determine a threshold BSA value for the prediction of chylothorax. This optimal BSA cutoff, other clinicopathological variables, and P < 0.15 were included into a multivariable logistic regression model to determine the risk factors for chylothorax.

Results

Twenty‐six patients (1.9%) developed postoperative chylothorax. The mean BSA in patients with chylothorax was significantly higher than in patients without (1.84 ± 0.14 vs. 1.73 ± 0.16 m²; P = 0.001). A BSA of 1.69 m² was identified as the threshold value with maximum joint sensitivity (96.2%) and specificity (43.8%). Patients with BSA > 1.69 m² had a significantly higher incidence of chylothorax (3.0% vs. 0.3%; P < 0.001) and a longer hospital stay (log rank P < 0.001) than patients with BSA ≤ 1.69 m². Multivariable logistic regression analysis suggested that BSA > 1.69 m² (odds ratio 7.35, 95% confidence interval 1.54–35.71; P = 0.013) was predictive of postoperative chylothorax.

Conclusions

BSA can serve as a novel categorical predictor for chylothorax complicating VATS lobectomy for NSCLC. It may be more helpful to incorporate a BSA cutoff into routine risk stratification tools for lung cancer surgery.