Evaluation of radiofrequency identification tag accuracy using bronchoscopy with fluoroscopy and virtual navigation guidance before segmentectomy.

BACKGROUND: The use of sublobar resection has increased with advances in imaging technologies. However, it is difficult for thoracic surgeons to identify small lung tumours intraoperatively. Radiofrequency identification (RFID) lung-marking systems are useful for overcoming this difficulty; however, accurate placement is essential for maximum effectiveness. METHODS: We retrospectively reviewed patients who underwent RFID tag placement via fluoroscopic bronchoscopy under virtual bronchoscopic navigation (VBN) guidance before our institution's sublobar resection of lung lesions. Thirty-one patients with 31 lung lesions underwent RFID lung-marking with fluoroscopic bronchoscopy under VBN guidance. RESULTS: Of the 31 procedures, 26 tags were placed within 10 mm of the target site, 2 were placed more than 10 mm away from the target site, and 3 were placed in a different area from the target bronchus. No clinical complications were associated with RFID tag placement, such as pneumothorax or bleeding. The contribution of the RFID lung-marking system to surgery was high, particularly when the RFID tag was placed at the target site and tumour was located in the intermediate hilar zone. CONCLUSIONS: An RFID tag can be placed near the target site using fluoroscopic bronchoscopy in combination with VBN guidance. RFID tag placement under fluoroscopic bronchoscopy with VBN guidance is useful for certain segmentectomies.

Analysis of postoperative weight loss associated with prognosis after sublobar resections for lung cancer.

OBJECTIVES: Sublobar resections for lung cancer are increasing worldwide. However, the prognostic significance of weight loss after sublobar resection remains unclear. We aimed to investigate the prognostic significance of weight loss after sublobar resection for lung cancer. METHODS: Patients who underwent sublobar resection for non-small cell lung cancer between January 2016 and June 2021 were analysed. The percentage weight change at 3, 6, and 12 months postoperatively was determined based on the preoperative weight. Patients were divided into two groups: those with or without weight loss ≥ 5%, referring to the diagnostic criteria for frailty, to assess prognosis. Subsequently, the prognosis-related timing of weight loss ≥ 5% and its risk factors were analyzed. RESULTS: We reviewed 147 patients; 39 (26.5%) showed weight loss ≥ 5% within 1-year post-surgery. A total of 32 patients (21.8%) died, 13 from primary lung cancer and 19 from non-lung cancer causes. Cancer recurrence occurred in 22 patients (15.0%). Weight loss ≥ 5% within 1-year post-surgery was a poor prognostic factor for overall and recurrence-free survival (log-rank; p = 0.014 and 0.018, respectively). Additionally, weight loss ≥ 5% at 6-12 months postoperatively was associated with poor overall and recurrence-free survival (p < 0.05, both). In the multivariable analysis, an age-adjusted Charlson comorbidity index ≥ 4 was a predictive factor for weight loss ≥ 5% at 6-12 months postoperatively (odds ratio, 3.920; p = 0.023). CONCLUSIONS: Weight loss ≥ 5% at 6-12 months postoperatively was associated with poor prognosis. Long-term nutritional management is important in the treatment plan of sublobar resection in high-risk patients.

Accurate Selection of Sublobar Resection for Small Non-small Cell Lung Cancer.

BACKGROUND: Although sublobar resection (wedge resection [Wed] or segmentectomy [Seg]) has become a standard operative procedure for clinical stages IA1 and IA2 non-small cell lung cancer (NSCLC) in Japan, the impact of this procedure on the prognosis and postoperative complications in real-world clinical practice is unknown. METHODS: This study retrospectively analyzed risk factors for a poor prognosis and postoperative complications of 470 patients with clinical stage ≤ IA2 NSCLC who underwent surgery from 2012 to 2021. RESULTS: Among the patients with a consolidation-to-tumor ratio (CTR) higher than 0.5, the 5-year relapse-free survival (RFS) rate was significantly lower in the Wed group (72.1%) than in the Seg (85.8%) and Lob (86.8%) groups (p < 0.01), but the difference between the Seg and Lob groups was not significant. Among patients with a CTR of 0.5 or lower, the 5-year RFS rate did not differ significantly among the three groups. Multivariable analysis of RFS showed that the prognosis was significantly worse in the Wed group than in the Lob group (hazard ratio, 2.83; p < 0.01), but the difference between the Wed and Seg groups or the between Seg and Lob groups was not significant. Multivariable analysis of postoperative complications showed a significantly lower risk in the Wed group than in the Seg group (odds ratio, 0.31; p < 0.01). CONCLUSIONS: Seg could become the standard operative procedure for clinical stages IA1 and IA2 NSCLC patients. Wed is suggested to be an option for patients with a CTR of 0.5 or lower and has the advantage of avoiding postoperative complications.

Outcomes and Survival for Early-Stage Non-Small Cell Lung Cancer Following Wedge Resection or Lobectomy: A Propensity Score-Matched Analysis Using a Novel Peruvian Registry.

Background: Using a previously unreported Peruvian registry of patients treated for early-stage non-small cell lung cancer (NSCLC), this study explored whether wedge resection and lobectomy were equivalent regarding survival and impact on radiologic-pathologic variables. Methods: This observational, analytical, longitudinal study used propensity score-matched (PSM) analysis of a single-center retrospective registry of 2,570 patients with pathologic stage I-II NSCLC who were treated with wedge resection (n=1,845) or lobectomy (n=725) during 2000-2020. After PSM, 650 cases were analyzed (resection, n=325; lobectomy, n=325) through preoperative and clinical variables, including patients with ≥1 lymph node removed. Kaplan-Meier curves and multivariable Cox proportional hazard models were created for 5-year overall survival (OS), disease-free survival (DFS), and locoregional-recurrence-free survival (LRFS). Results: The principal complication was operative pain persisting >7 days for lobectomy versus wedge resection (58% vs. 23%, p=0.034) and shorter hospital stays for resection than for lobectomy (5.3 days vs. 12.8 days, p=0.009). The 5-year OS (84.3% vs. 81.2%, p=0.09) and DFS (79.1% vs. 74.1%, p=0.07) were similar and statistically insignificant between resections and lobectomies, respectively. LRFS was worse overall following wedge resection than lobectomy (79.8% vs. 91.1%, p<0.02). Nevertheless, in the PSM analysis, both groups experienced similar LRFS when the resection margin was >10 mm (90.9% vs. 87.3%, p<0.048) and ≥4 lymph nodes were removed (82.8% vs. 79.1%, p<0.011). Conclusion: Both techniques led to similar OS and DFS at 5 years; however, successful LRFS required a wedge resection with a surgical margin and adequate lymph node removal to obtain outcomes similar to lobectomy.

Sublobar resection for lung adenocarcinoma less than 2 cm containing solid or micropapillary components radiologically presented as consolidation-to-tumor ratio (CTR) ≤0.25 [ground-glass opacity (GGO)].

Background: The suitability of sublobar resection as a surgical approach for early-stage non-small cell lung cancer (NSCLC) remains unclear. This study investigated the feasibility of sublobar resection in patients with pathological-stage IA adenocarcinoma less than 2 cm characterized by a high-risk pathological subtype but exhibiting radiologically noninvasive features. Methods: We conducted a retrospective review of patients diagnosed with pathological stage IA lung adenocarcinoma who underwent surgical intervention between 2013 and 2017. The inclusion criteria included a maximum tumor diameter of 2.0 cm or less, a consolidation-to-tumor ratio (CTR) of 0.25 or less, and a histopathological confirmation of a solid or micropapillary component. Patients were categorized into sublobar resection and lobectomy groups, and propensity score matching was employed to mitigate potential confounders. The primary endpoints were lung cancer-specific survival (LCSS) and overall survival (OS). Results: The study comprised 149 patients, with 84 in the lobectomy group and 65 in the limited resection group. In the overall cohort, the 5-year LCSS was 100% for both groups, while the 5-year OS was 97.6% (95% CI: 94.41-100.00%) in the lobectomy group and 100% in the sublobar resection group (P=0.21). After propensity score matching, the LCSS remained at 100% for both groups, and the 5-year OS was 97.14% in the lobectomy group and 100% in the sublobar resection group (P=0.32). Conclusions: Based on our experience, for lung adenocarcinoma containing solid/micropapillary subtype, a size less than 2 cm, and a CTR ≤0.25, the oncological outcomes appeared to be comparable between sublobar resection and lobectomy, suggesting that sublobar resection might serve as an equivalent alternative to lobectomy for such lesions.

An analysis of residual lung volume changes after segmentectomy based on three-dimensional computed tomography.

Background: Based on the results of JCOG0802 and CALGB studies, segmentectomy has considered to be a standard procedure for early-stage non-small cell lung cancer (NSCLC). After lobectomy, the residual cavity is filled with mediastinal and diaphragmatic deviations, and compensatory volume changes are present in the residual lungs. In this study, we examined the efficacy of segmentectomy, a surgical procedure, by focusing on its impact on postoperative lung volume and function. Methods: We enrolled 77 patients who underwent segmentectomy as their initial surgical procedure, excluding those with additional lung resections and those who lacked postoperative computed tomography imaging. The predicted residual volume (mL) was defined as the total lung volume before surgery minus the volume of the resected area. Using the predicted residual volume (mL) and postoperative total lung volume (mL), we calculated the rate of postoperative lung volume increase [(postoperative total lung volume/predicted residual volume) × 100] (%). We also classified 52 cases with a rate of postoperative lung volume increase of ≥100% into a compensatory group, while those with a rate of <100% were classified into a non-compensatory group. Results: The average postoperative lung volume increase was 104.6% among 77 cases. Age ≥65 years, pack year index ≥27.5, ≥3 resected segments, and use of electrocautery for intersegmental plane division were significantly associated with compensatory group classification. In 20 compensatory cases with preoperative and postoperative pulmonary function tests, postoperative vital capacity and forced expiratory volume in one second values exceeded the preoperative predictions. This study further examined the areas responsible for postoperative compensatory lung volume increase. In the compensatory group, significant expansion was observed in the ipsilateral lobes, excluding the resected segment and contralateral lung, while no significant changes were noted in the volume of the lobe, including the resected segment. Conversely, the non-compensatory group showed a significant volume decrease in the resected lobe, but no significant increase in other areas. Conclusions: This study emphasizes the importance of preserving lung segments in segmentectomy. The study demonstrates extensive compensatory volume changes in the ipsilateral lung and contralateral lung. There was no significant volume decrease in any residual segment. This underlines the potential of segmentectomy to maintain lung function and expand treatment options post-surgery. In addition, the compensated group included patients with a lower pack-year index and younger patients. These results suggest that postoperative compensatory lung expansion includes not only hyperinflation of the remaining lung, but also an increase in the functional lung parenchyma.

Real-world outcomes of lobectomy, segmentectomy and wedge resection for the treatment of stage c-IA lung carcinoma.

OBJECTIVES: To determine safety and survival outcomes associated with lobectomy, segmentectomy and wedge resection for early-stage lung cancer by quiring the French population-based registry EPIdemiology in THORacic surgery (EPITHOR). METHODS: Retrospective analysis of 19 452 patients with stage c IA lung carcinoma who underwent lobectomy, segmentectomy or wedge resection between 2016 and 2022 with curative-intent. Main outcome measures were 90-day mortality and 5-year overall survival estimates. Proportional hazards regression and propensity score matching were used to adjust outcomes for key patient, tumour and practice environment factors. RESULTS: The treatment distribution was 72.2% for lobectomy, 21.5% for segmentectomy and 6.3% for wedge. Unadjusted 90-day mortality rates were 1.6%, 1.2% and 1.1%, respectively (P = 0.10). Unadjusted 5-year overall survival estimates were 80%, 78% and 70%, with significant inter-group survival curves differences (P < 0.0001). Multivariable proportional hazards regression showed that wedge was associated with worse overall survival [adjusted hazard ratio (AHR), 1.23 (95% confidence interval 1.03-1.47); P = 0.021] compared with lobectomy, while no significant difference was disclosed when comparing segmentectomy to lobectomy (1.08 [0.97-1.20]; P = 0.162). The three-way propensity score analyses confirmed similar 90-day mortality rate for wedge resection and segmentectomy compared with lobectomy (hazard ratio: 0.43; 95% confidence interval 0.16-1.11; P = 0.081 and 0.99; 0.48-2.10; P = 0.998, respectively), but poorer overall survival (1.45; 1.13-1.86; P = 0.003 and 1.31; 1-1.71; P = 0.048, respectively). CONCLUSIONS: Wedge resection was associated with comparable 90-day mortality but lower overall survival when compared to lobectomy. Overall, all types of sublobar resections may not offer equivalent oncologic effectiveness in real-world settings.

The Clinical Role of Adjuvant Chemotherapy after Sublobar Resection for Non-Small-Cell Lung Cancer ≤ 20 mm with Lymph Node Metastases: A Propensity-Matched Analysis of the National Cancer Database.

Sublobar resection is a standard surgical procedure for small-sized non-small-cell lung cancer (NSCLC). However, the clinical role of adjuvant chemotherapy for small-sized NSCLC with pathological lymph node (LN) metastasis after sublobar resection is unknown. The National Cancer Database was queried for NSCLC patients between 2004 and 2018. Eligibility included sublobar resection with pathological LN metastasis, R0 resection, Charlson comorbidity score = 0, clinical stage T1a-b, and tumor size ≤ 20 mm. The Kaplan-Meier method with a log-rank test and multivariable Cox proportional hazards analyses were used for assessing survival. The samples were evaluated before and after propensity score matching (PSM) with respect to age, sex, histologic type, and pathological LN status. Of 810 patients who met the eligibility criteria, 567 (70.0%) underwent adjuvant chemotherapy. After PSM, patients with adjuvant chemotherapy had a significantly longer survival than those without (median survival: 64.3 vs. 34.0 months, hazard ratio for death: 0.61, p < 0.0001). Multivariate analyses after PSM showed that younger age (p = 0.0206), female (p = 0.0005), and adjuvant chemotherapy (p < 0.0001) were independent prognostic factors for longer survival. Adjuvant chemotherapy has a prognostic impact in patients with small-sized NSCLC and pathological lymph node metastasis who undergo sublobar resection.

Quantification of Resection Margin following Sublobar Resection in Lung Cancer Patients through Pre- and Post-Operative CT Image Comparison: Utilizing a CT-Based 3D Reconstruction Algorithm.

Sublobar resection has emerged as a standard treatment option for early-stage peripheral non-small cell lung cancer. Achieving an adequate resection margin is crucial to prevent local tumor recurrence. However, gross measurement of the resection margin may lack accuracy due to the elasticity of lung tissue and interobserver variability. Therefore, this study aimed to develop an objective measurement method, the CT-based 3D reconstruction algorithm, to quantify the resection margin following sublobar resection in lung cancer patients through pre- and post-operative CT image comparison. An automated subvascular matching technique was first developed to ensure accuracy and reproducibility in the matching process. Following the extraction of matched feature points, another key technique involves calculating the displacement field within the image. This is particularly important for mapping discontinuous deformation fields around the surgical resection area. A transformation based on thin-plate spline is used for medical image registration. Upon completing the final step of image registration, the distance at the resection margin was measured. After developing the CT-based 3D reconstruction algorithm, we included 12 cases for resection margin distance measurement, comprising 4 right middle lobectomies, 6 segmentectomies, and 2 wedge resections. The outcomes obtained with our method revealed that the target registration error for all cases was less than 2.5 mm. Our method demonstrated the feasibility of measuring the resection margin following sublobar resection in lung cancer patients through pre- and post-operative CT image comparison. Further validation with a multicenter, large cohort, and analysis of clinical outcome correlation is necessary in future studies.

AI-driven Characterization of Solid Pulmonary Nodules on CT Imaging for Enhanced Malignancy Prediction in Small-sized Lung Adenocarcinoma.

OBJECTIVES: Distinguishing solid nodules from nodules with ground-glass lesions in lung cancer is a critical diagnostic challenge, especially for tumors ≤2 cm. Human assessment of these nodules is associated with high inter-observer variability, which is why an objective and reliable diagnostic tool is necessary. This study focuses on artificial intelligence (AI) to automatically analyze such tumors and to develop prospective AI systems that can independently differentiate highly malignant nodules. MATERIALS AND METHODS: Our retrospective study analyzed 246 patients who were diagnosed with negative clinical lymph node metastases (cN0) using positron emission tomography-computed tomography (PET/CT) imaging and underwent surgical resection for lung adenocarcinoma. AI detected tumor sizes ≤2 cm in these patients. By utilizing AI to classify these nodules as solid (AI_solid) or non-solid (non-AI_solid) based on confidence scores, we aim to correlate AI determinations with pathological findings, thereby advancing the precision of preoperative assessments. RESULTS: Solid nodules identified by AI with a confidence score ≥0.87 showed significantly higher solid component volumes and proportions in patients with AI_solid than in those with non-AI_solid, with no differences in overall diameter or total volume of the tumors. Among patients with AI_solid, 16% demonstrated lymph node metastasis, and a significant 94% harbored invasive adenocarcinoma. Additionally, 44% were upstaging postoperatively. These AI_solid nodules represented high-grade malignancies. CONCLUSION: In small-sized lung cancer diagnosed as cN0, AI automatically identifies tumors as solid nodules ≤2 cm and evaluates their malignancy preoperatively. The AI classification can inform lymph node assessment necessity in sublobar resections, reflecting metastatic potential.

Simply designed robotic combined subsegmentectomy for a lesion in the left S10 via a posterior approach.

Segmentectomies involving the posterior basal segment (S10) of the lower lobe present a challenging surgical procedure due to anatomical complexities, especially when lesions extend towards the lateral basal segment (S9). We introduce a combined subsegmentectomy technique via a posterior approach for a lesion situated between S9b and S10b, which preserves subsegmental branches that do not affect the resection margin of the tumour and facilitates intersegmental division without extending dissection into the interlobar region. This technique, the goal of which is to reduce the extent of dissection and complex stapling, is expected to minimize pulmonary complications and intrathoracic adhesions without compromising oncological outcomes. By potentially mitigating challenges in an ipsilateral reoperation, this approach offers a valuable alternative for managing second lung cancers.

Preoperative evaluation of visceral pleural invasion in peripheral lung cancer utilizing deep learning technology.

PURPOSE: This study aimed to assess the efficiency of artificial intelligence (AI) in the detection of visceral pleural invasion (VPI) of lung cancer using high-resolution computed tomography (HRCT) images, which is challenging for experts because of its significance in T-classification and lymph node metastasis prediction. METHODS: This retrospective analysis was conducted on preoperative HRCT images of 472 patients with stage I non-small cell lung cancer (NSCLC), focusing on lesions adjacent to the pleura to predict VPI. YOLOv4.0 was utilized for tumor localization, and EfficientNetv2 was applied for VPI prediction with HRCT images meticulously annotated for AI model training and validation. RESULTS: Of the 472 lung cancer cases (500 CT images) studied, the AI algorithm successfully identified tumors, with YOLOv4.0 accurately localizing tumors in 98% of the test images. In the EfficientNet v2-M analysis, the receiver operating characteristic curve exhibited an area under the curve of 0.78. It demonstrated powerful diagnostic performance with a sensitivity, specificity, and precision of 76.4% in VPI prediction. CONCLUSION: AI is a promising tool for improving the diagnostic accuracy of VPI for NSCLC. Furthermore, incorporating AI into the diagnostic workflow is advocated because of its potential to improve the accuracy of preoperative diagnosis and patient outcomes in NSCLC.

[Impact of the Size and Depth of Pulmonary Nodules on the Surgical Approach 
for Lung Resection in the Treatment of Early-stage Lung Cancer ≤2 cm].

BACKGROUND: Current studies suggest that for early-stage lung cancers with a component of ground-glass opacity measuring ≤2 cm, sublobar resection is suitable if it ensures adequate margins. However, lobectomy may be necessary for some cases to achieve this. The aim of this study was to explore the impact of size and depth on surgical techniques for wedge resection, segmentectomy, and lobectomy in early-stage lung cancer ≤2 cm, and to determine methods for ensuring a safe resection margin during sublobar resections. METHODS: Clinical data from 385 patients with early-stage lung cancer ≤2 cm, who underwent lung resection in 2022, were subject to a retrospective analysis, covering three types of procedures: wedge resection, segmentectomy and lobectomy. The depth indicator as the OA value, which is the shortest distance from the inner edge of a pulmonary nodule to the opening of the corresponding bronchus, and the AB value, which is the distance from the inner edge of the nodule to the pleura, were measured. For cases undergoing lobectomy and segmentectomy, three-dimensional computed tomography bronchography and angiography (3D-CTBA) was performed to statistically determine the number of subsegments required for segmentectomy. The cutting margin width for wedge resection and segmentectomy was recorded, as well as the specific subsegments and their quantities removed during lung segmentectomy were documented. RESULTS: In wedge resection, segmentectomy, and lobectomy, the sizes of pulmonary nodules were (1.08±0.29) cm, (1.31±0.34) cm and (1.50±0.35) cm, respectively, while the depth of the nodules (OA values) was 6.05 (5.26, 6.85) cm, 4.43 (3.27, 5.43) cm and 3.04 (1.80, 4.18) cm for each procedure, showing a progressive increasing trend (P<0.001). The median resection margin width obtained from segmentectomy was 2.50 (1.50, 3.00) cm, significantly greater than the 1.50 (1.15, 2.00) cm from wedge resection (P<0.001). In wedge resections, cases where AB value >2 cm demonstrated a higher proportion of cases with resection margins less than 2 cm compared to those with margins greater than 2 cm (29.03% vs 12.90%, P=0.019). When utilizing the size of the nodule as the criterion for resection margin, the instances with AB value >2 cm continued to show a higher proportion in the ratio of margin distance to tumor size less than 1 (37.50% vs 17.39%, P=0.009). The median number of subsegments for segmentectomy was three, whereas lobectomy cases requiring segmentectomy involved five subsegments (P<0.001). CONCLUSIONS: The selection of the surgical approach for lung resection is influenced by both the size and depth of pulmonary nodules. This study first confirms that larger portions of lung tissue must be removed for nodules that are deeper and larger to achieve a safe margin. A distance of ≤2 cm from the inner edge of the pulmonary nodule to the nearest pleura may be the ideal indication for performing wedge resection.