Visceral Pleural Invasion Classification in Non–Small-Cell Lung Cancer in the 7th Edition of the Tumor, Node, Metastasis Classification for Lung Cancer: Validation Analysis Based on a Large-Scale Nationwide Database

Site-specific follow-up strategy for surgically resected patients with NSCLC based on ten-year follow-up data

OBJECTIVES

There is currently no consensus regarding the optimal site-specific postoperative follow-up duration for patients with completely resected non-small cell lung cancer. Long-term surveillance for recurrence may lead to psychological distress or economic burdens for patients.We aimed to propose an appropriate site-specific follow-up strategy for patients with non-small cell lung cancer based on 10-year follow-up data.

MATERIALS AND METHODS

We analyzed recurrence patterns in 2,359 patients with non-small cell lung cancer who underwent surgical resection from 2008 to 2013. We established potential site-specific follow-up endpoints when the subsequent recurrence rates fell below 5% and proposed a corresponding follow-up strategy.

RESULTS

With a median follow-up of 111.0 months, postoperative recurrences were observed in 985 patients (41.8 %). We identified several factors associated with site-specific recurrence recurrence patterns, including ground-glass opacity component, sex, histology type, and pathological TNM stage. No recurrence was observed in patients with pure ground-glass nodules, a consolidation-to-tumor ratio less than 0.5, or a pathological type classified as lepidic pattern-predominant adenocarcinoma. In thorax, brain and bone, patients with non-squamous cell carcinoma exhibited higher recurrence rates than those with squamous cell carcinoma. In abdomen and neck, male patients have a higher recurrence rate than female patients, particularly within the pathological stage III group.

CONCLUSIONS

The follow-up strategy was developed based on the recurrence patterns analyzed from ten-year follow-up data. The online tool may assist in determining the optimal site-specific duration for surveillance based on clinicopathologic features.

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.

The International Association for the Study of Lung Cancer Lung Cancer Staging Project: Application and Interpretation of the Residual Tumor Classification for Lung Cancer-Results from an International Survey Among Pathologists and Thoracic Surgeons

OBJECTIVES

The study aimed to assess the opinion of pathologists and thoracic surgeons of the International Association for the Study of Lung Cancer regarding the application and interpretation of the residual tumor (R) classification for lung cancer.

METHODS

On the basis of their membership profiles, a total of 623 pathologists and thoracic surgeons were identified and contacted by email with a cover letter and a link to an online survey. The questionnaire consisted of 12 questions about various aspects of the application and interpretation of the R classification for lung cancer. The response rate (to at least one question) was 72% (144 pathologists and 303 surgeons).

RESULTS

The frequency of use of the R classification varies by geographic region. Although R status is regularly reported in Europe and Asia, 70% of pathologists in the United States and Canada never include R status in reports. Similar variations exist about who assigns the R category for the resection-in Europe and the United Kingdom, it is mainly the pathologist, whereas in China, Japan and the United States, it is the surgeon. There are some good agreements about margins examined and how to manage staple lines. The category "uncertain resection" has not been practically implemented in most of the world, except at some centers in Japan and the United Kingdom.

CONCLUSION

This survey shows that surgical resection margins are part of routine reporting in most institutions; but the assignment of an R category is not always part of the pathology report, with considerable variation between countries. Despite the International Association for the Study of Lung Cancer proposals, the application of the uncertain resection category has not been taken up by most institutions, and further evidence is needed.

Prediction of visceral pleural invasion of clinical stage I lung adenocarcinoma using thoracoscopic images and deep learning

PURPOSE

To develop deep learning models using thoracoscopic images to identify visceral pleural invasion (VPI) in patients with clinical stage I lung adenocarcinoma, and to verify if these models can be applied clinically.

METHODS

Two deep learning models, one based on a convolutional neural network (CNN) and the other based on a vision transformer (ViT), were applied and trained via 463 images (VPI negative: 269 images, VPI positive: 194 images) captured from surgical videos of 81 patients. Model performances were validated via an independent test dataset containing 46 images (VPI negative: 28 images, VPI positive: 18 images) from 46 test patients.

RESULTS

The areas under the receiver operating characteristic curves of the CNN-based and ViT-based models were 0.77 and 0.84 (p = 0.304), respectively. The accuracy, sensitivity, specificity, and positive and negative predictive values were 73.91, 83.33, 67.86, 62.50, and 86.36% for the CNN-based model and 78.26, 77.78, 78.57, 70.00, and 84.62% for the ViT-based model, respectively. These models' diagnostic abilities were comparable to those of board-certified thoracic surgeons and tended to be superior to those of non-board-certified thoracic surgeons.

CONCLUSION

The deep learning model systems can be utilized in clinical applications via data expansion.

Prognostication of lung adenocarcinomas using CT-based deep learning of morphological and histopathological features: a retrospective dual-institutional study

OBJECTIVES

To develop and validate CT-based deep learning (DL) models that learn morphological and histopathological features for lung adenocarcinoma prognostication, and to compare them with a previously developed DL discrete-time survival model.

METHODS

DL models were trained to simultaneously predict five morphological and histopathological features using preoperative chest CT scans from patients with resected lung adenocarcinomas. The DL score was validated in temporal and external test sets, with freedom from recurrence (FFR) and overall survival (OS) as outcomes. Discrimination was evaluated using the time-dependent area under the receiver operating characteristic curve (TD-AUC) and compared with the DL discrete-time survival model. Additionally, we performed multivariable Cox regression analysis.

RESULTS

In the temporal test set (640 patients; median age, 64 years), the TD-AUC was 0.79 for 5-year FFR and 0.73 for 5-year OS. In the external test set (846 patients; median age, 65 years), the TD-AUC was 0.71 for 5-year OS, equivalent to the pathologic stage (0.71 vs. 0.71 [p = 0.74]). The prognostic value of the DL score was independent of clinical factors (adjusted per-percentage hazard ratio for FFR (temporal test), 1.02 [95% CI: 1.01-1.03; p < 0.001]; OS (temporal test), 1.01 [95% CI: 1.002-1.02; p = 0.01]; OS (external test), 1.01 [95% CI: 1.005-1.02; p < 0.001]). Our model showed a higher TD-AUC than the DL discrete-time survival model, but without statistical significance (2.5-year OS: 0.73 vs. 0.68; p = 0.13).

CONCLUSION

The CT-based prognostic score from collective deep learning of morphological and histopathological features showed potential in predicting survival in lung adenocarcinomas.

CLINICAL RELEVANCE STATEMENT

Collective CT-based deep learning of morphological and histopathological features presents potential for enhancing lung adenocarcinoma prognostication and optimizing pre-/postoperative management.

KEY POINTS

• A CT-based prognostic model was developed using collective deep learning of morphological and histopathological features from preoperative CT scans of 3181 patients with resected lung adenocarcinoma. • The prognostic performance of the model was comparable-to-higher performance than the pathologic T category or stage. • Our approach yielded a higher discrimination performance than the direct survival prediction model, but without statistical significance (0.73 vs. 0.68; p=0.13).

Clinical Utility of a CT-based AI Prognostic Model for Segmentectomy in Non-Small Cell Lung Cancer

Background Currently, no tool exists for risk stratification in patients undergoing segmentectomy for non-small cell lung cancer (NSCLC). Purpose To develop and validate a deep learning (DL) prognostic model using preoperative CT scans and clinical and radiologic information for risk stratification in patients with clinical stage IA NSCLC undergoing segmentectomy. Materials and Methods In this single-center retrospective study, transfer learning of a pretrained model was performed for survival prediction in patients with clinical stage IA NSCLC who underwent lobectomy from January 2008 to March 2017. The internal set was divided into training, validation, and testing sets based on the assignments from the pretraining set. The model was tested on an independent test set of patients with clinical stage IA NSCLC who underwent segmentectomy from January 2010 to December 2017. Its prognostic performance was analyzed using the time-dependent area under the receiver operating characteristic curve (AUC), sensitivity, and specificity for freedom from recurrence (FFR) at 2 and 4 years and lung cancer-specific survival and overall survival at 4 and 6 years. The model sensitivity and specificity were compared with those of the Japan Clinical Oncology Group (JCOG) eligibility criteria for sublobar resection. Results The pretraining set included 1756 patients. Transfer learning was performed in an internal set of 730 patients (median age, 63 years [IQR, 56-70 years]; 366 male), and the segmentectomy test set included 222 patients (median age, 65 years [IQR, 58-71 years]; 114 male). The model performance for 2-year FFR was as follows: AUC, 0.86 (95% CI: 0.76, 0.96); sensitivity, 87.4% (7.17 of 8.21 patients; 95% CI: 59.4, 100); and specificity, 66.7% (136 of 204 patients; 95% CI: 60.2, 72.8). The model showed higher sensitivity for FFR than the JCOG criteria (87.4% vs 37.6% [3.08 of 8.21 patients], P = .02), with similar specificity. Conclusion The CT-based DL model identified patients at high risk among those with clinical stage IA NSCLC who underwent segmentectomy, outperforming the JCOG criteria. © RSNA, 2024 Supplemental material is available for this article.

The association of visceral pleural invasion with skip N2 metastasis on clinical stage IA NSCLC

BACKGROUND

Lung lymphatic drainage occurs mainly through a peribronchial path, but it is hypothesized that visceral pleural invasion could alter this path. This study aims to investigate the association between visceral pleural invasion, node upstaging, and N2 skip metastasis and the impact on survival in a population of patients with non-small cell lung cancer of 3 cm or smaller.

METHODS

We retrospectively queried our institutional database of lung cancer resection for all patients with clinical stage IA NSCLC between June 2009 and June 2022. We collected baseline characteristics and clinical and pathological staging data. Patients were classified into two groups: The non-VPI group with negative visceral pleural invasion and the VPI group with positive. The primary results analyzed were the occurrence of nodal upstaging, skip N2 metastasis and recurrence.

RESULTS

There were 320 patients analyzed. 61.3 % were women; the median age was 65.4 years. The pleural invasion occurred in 44 patients (13.7 %). VPI group had larger nodules (2.3 vs. 1.7 cm; p < 0.0001), higher 18F-FDG uptake (7.4 vs. 3.4; p < 0.0001), and lymph-vascular invasion (35.7 % vs. 13.5 %, p = 0.001). Also, the VPI group had more nodal disease (25.6 % vs. 8.7 %; p = 0.001) and skip N2 metastasis (9.3 % vs. 1.8 %; p = 0.006). VPI was a statistically independent factor for skip N2 metastasis. Recurrence occurred in 17.2 % of the population. 5-year disease-free and overall survival were worse in the VPI group.

CONCLUSIONS

The visceral pleural invasion was an independent factor associated with N2 skip metastasis and had worse disease-free and overall survival.

Diagnosis, treatment, and prognosis of stage IB non-small cell lung cancer with visceral pleural invasion

With the increasing implementation of early lung cancer screening and the increasing emphasis on physical examinations, the early-stage lung cancer detection rate continues to rise. Visceral pleural invasion (VPI), which denotes the tumor's breach of the elastic layer or reaching the surface of the visceral pleura, stands as a pivotal factor that impacts the prognosis of patients with non-small cell lung cancer (NSCLC) and directly influences the pathological staging of early-stage cases. According to the latest 9th edition of the TNM staging system for NSCLC, even when the tumor diameter is less than 3 cm, the final T stage remains T2a if VPI is present. There is considerable controversy within the guidelines regarding treatment options for stage IB NSCLC, especially among patients exhibiting VPI. Moreover, the precise determination of VPI is important in guiding treatment selection and prognostic evaluation in individuals with NSCLC. This article aims to provide a comprehensive review of the current status and advancements in studies pertaining to stage IB NSCLC accompanied by VPI.

Development and validation of 18F-FDG PET/CT radiomics-based nomogram to predict visceral pleural invasion in solid lung adenocarcinoma

OBJECTIVES

This study aimed to establish a radiomics model based on 18F-FDG PET/CT images to predict visceral pleural invasion (VPI) of solid lung adenocarcinoma preoperatively.

METHODS

We retrospectively enrolled 165 solid lung adenocarcinoma patients confirmed by histopathology with 18F-FDG PET/CT images. Patients were divided into training and validation at a ratio of 0.7. To find significant VPI predictors, we collected clinicopathological information and metabolic parameters measured from PET/CT images. Three-dimensional (3D) radiomics features were extracted from each PET and CT volume of interest (VOI). Receiver operating characteristic (ROC) curve was performed to determine the performance of the model. Accuracy, sensitivity, specificity and area under curve (AUC) were calculated. Finally, their performance was evaluated by concordance index (C-index) and decision curve analysis (DCA) in training and validation cohorts.

RESULTS

165 patients were divided into training cohort (n = 116) and validation cohort (n = 49). Multivariate analysis showed that histology grade, maximum standardized uptake value (SUVmax), distance from the lesion to the pleura (DLP) and the radiomics features had statistically significant differences between patients with and without VPI (P < 0.05). A nomogram was developed based on the logistic regression method. The accuracy of ROC curve analysis of this model was 75.86% in the training cohort (AUC: 0.867; C-index: 0.867; sensitivity: 0.694; specificity: 0.889) and the accuracy rate in validation cohort was 71.55% (AUC: 0.889; C-index: 0.819; sensitivity: 0.654; specificity: 0.739).

CONCLUSIONS

A PET/CT-based radiomics model was developed with SUVmax, histology grade, DLP, and radiomics features. It can be easily used for individualized VPI prediction.

Advances in diagnosis and prediction for aggression of pure solid T1 lung cancer

A growing number of early-stage lung cancers presenting as malignant pulmonary nodules have been diagnosed because of the increased adoption of low-dose spiral computed tomography. But pure solid T1 lung cancer with ≤3 cm in the greatest dimension is not always at an early stage, despite its small size. This type of cancer can be highly aggressive and is associated with pathological involvement, metastasis, postoperative relapse, and even death. However, it is easily misdiagnosed or delay diagnosed in clinics and thus poses a serious threat to human health. The percentage of nodal or extrathoracic metastases has been reported to be >20% in T1 lung cancer. As such, understanding and identifying the aggressive characteristics of pure solid T1 lung cancer is crucial for prevention, diagnosis, and therapeutic strategies, and beneficial to improving the prognosis. With the widespread of lung cancer screening, these highly invasive pure solid T1 lung cancer will become the main advanced lung cancer in future. However, there is limited information regarding precision medicine on how to identify these "early-stage" aggressive lung cancers. To provide clinicians with new insights into early recognition and intervention of the highly invasive pure solid T1 lung cancer, this review summarizes its clinical characteristics, imaging, pathology, gene alterations, immune microenvironment, multi-omics, and current techniques for diagnosis and prediction.

Computed Tomography-based Prognostication in Lung Adenocarcinomas through Histopathological Feature Learning: A Retrospective Multicenter Study

Rationale: Modeling imaging surrogates for well-validated histopathological risk factors would enable prognostication in early-stage lung adenocarcinomas. Objectives: We aimed to develop and validate computed tomography (CT)-based deep learning (DL) models for the prognostication of early-stage lung adenocarcinomas through learning histopathological features and to investigate the models' reproducibility using retrospective, multicenter datasets. Methods: Two DL models were trained to predict visceral pleural invasion and lymphovascular invasion, respectively, using preoperative chest CT scans from 1,426 patients with stage I-IV lung adenocarcinomas. The averaged model output was defined as the composite score and evaluated for the prognostic discrimination and its added value to clinicopathological factors in temporal (n = 610) and external test sets (n = 681) of stage I lung adenocarcinomas. The study outcomes were freedom from recurrence (FFR) and overall survival (OS). Interscan and interreader reproducibility were analyzed in 31 patients with lung cancer who underwent same-day repeated CT scans. Results: For the temporal test set, the time-dependent area under the receiver operating characteristic curve was 0.76 (95% confidence interval [CI], 0.71-0.81) for 5-year FFR and 0.67 (95% CI, 0.59-0.75) for 5-year OS. For the external test set, the area under the curve was 0.69 (95% CI, 0.63-0.75) for 5-year OS. The discrimination performance remained stable in 10-year follow-up for both outcomes. The prognostic value of the composite score was independent of and complementary to the clinical factors (adjusted per-percent hazard ratio for FFR [temporal test], 1.04 [95% CI, 1.03-1.05; P < 0.001]; OS [temporal test], 1.03 [95% CI, 1.02-1.04; P < 0.001]; OS [external test], 1.03 [95% CI, 1.02-1.04; P < 0.001]). The likelihood ratio tests indicated added value of the composite score (all P < 0.05). The interscan and interreader reproducibility were excellent (Pearson's correlation coefficient, 0.98 for both). Conclusions: The CT-based composite score obtained from DL of histopathological features predicted survival in early-stage lung adenocarcinomas with high reproducibility.

Clinical Significance of Dual-Block Elastic Stain Evaluating Visceral Pleural Invasion in Peripheral Non-Small Cell Lung Cancer

Visceral pleural invasion (VPI) is a critical component in the staging of peripheral non-small cell lung carcinoma (NSCLC). We aim to investigate whether dual-block elastic stain increases visceral pleural invasion positivity compared with single-block elastic stain. We further analyze the potential predictors of visceral pleural invasion. 8419 peripheral NSCLC patients (including 6008 patients with tumor size≤3 cm in stage I) were divided into a cohort using one paraffin block (single-block group, n = 5184) and a cohort using dual paraffin blocks (dual-block group, n = 3235) for elastic stain. The VPI-positive rate demonstrated by the dual-block elastic stains group was significantly higher than that of the single-block elastic stain group (17.7% (573/3235) versus 9.1% (474/5184), respectively, P < .001). The presence of visceral pleural invasion in T1 (≤3 cm) patients detected by single- and dual-block elastic stain was 6.3% (235/3730) and 12.0% (273/2278), respectively (P < .001). 5.7% of T1 patients (stage IA) were additionally upstaged to T2a (stage IB) by dual-block elastic stain. However, the incidence of visceral pleural invasion in pT2a patients showed no significant difference between the single-block group and the dual-block group (16.8% vs. 17.1%, P = .916). Lymphovascular invasion, lymph node metastasis, dedifferentiated carcinomas, the presence of spread through airspaces (STAS) and a poorly differentiated adenocarcinomatous growth pattern could be significant predictors of visceral pleural invasion (P < .001). Our results indicate that using dual-block elastic stain identifies more visceral pleural invasion positive T1 NSCLC patients who are upstaged to T2a, and who could benefit from optimal management post-operatively. The application of dual-block elastic stain is an efficient and practical method to detect visceral pleural invasion status.

Lipid biomarkers that reflect postoperative recurrence risk in lung cancer patients who smoke: a case-control study

BACKGROUND

The risk of postoperative recurrence is higher in lung cancer patients who smoke than non-smokers. However, objective evaluation of the postoperative recurrence risk is difficult using conventional pathological prognostic factors because of their lack of reproducibility. Consequently, novel objective biomarkers that reflect postoperative risk in lung cancer patients who smoke must be identified. Because cigarette smoking and oncogenesis alter lipid metabolism in lung tissue, we hypothesized that the lipid profiles in lung cancer tissues are influenced by cigarette smoking and can reflect the postoperative recurrence risk in smoking lung cancer patients. This study aimed to identify lipid biomarkers that reflect the smoking status and the postoperative recurrence risk.

METHODS

Primary tumor tissues of lung adenocarcinoma (ADC) (n = 26) and squamous cell carcinoma (SQCC) (n = 18) obtained from surgery were assigned to subgroups according to the patient's smoking status. The ADC cohort was divided into never smoker and smoker groups, while the SQCC cohort was divided into moderate smoker and heavy smoker groups. Extracted lipids from the tumor tissues were subjected to liquid chromatography-tandem mass spectrometry analysis. Lipids that were influenced by smoking status and reflected postoperative recurrence and pathological prognostic factors were screened.

RESULTS

Two and 12 lipid peaks in the ADC and SQCC cohorts showed a significant positive correlation with the Brinkman index, respectively. Among them, in the ADC cohort, a higher lipid level consisted of three phosphatidylcholine (PC) isomers, PC (14:0_18:2), PC (16:1_16:1), and PC (16:0_16:2), was associated with a shorter recurrence free period (RFP) and a greater likelihoods of progressed T-factor (≥ pT2) and pleural invasion. In the SQCC cohort, a lower m/z 736.5276 level was associated with shorter RFP and greater likelihood of recurrence.

CONCLUSIONS

From our data, we propose three PC isomers, PC (14:0_18:2), PC (16:1_16:1), and PC (16:0_16:2), and a lipid peak of m/z 736.5276 as novel candidate biomarkers for postoperative recurrence risk in lung ADC and SQCC patients who are smokers.

Comparison of the geriatric nutritional risk index and the prognostic nutritional index in determining survival outcome in patients with non-small cell lung cancer undergoing surgical resection: A cohort study

To assess the clinical feasibility of the geriatric nutritional risk index (GNRI) and prognostic nutritional index (PNI) as determinants of survival in patients with stage I to III non-small cell lung cancer (NSCLC). This retrospective study included patients with stage I to III NSCLC from all age groups. Hazard ratios (HRs) for overall survival (OS), cancer-specific survival (CSS), and relapse-free survival (RFS) were calculated using the Cox regression analysis. The concordance index (C-index) of the models was evaluated following the establishment of the prognostic models for survival. The median patient age was 69 years, and 64.6% of the patients were male. In total, 172 (65.4%) patients were classified as having stage I disease, 52 (19.8%) as stage II disease, and 39 (14.8%) as stage III disease. Using multivariate Cox regression analysis, the HRs of GNRI for OS, CSS, and RFS were 0.37 (P = .003), 0.47 (P = .041), and 0.38 (P < .001), respectively. However, the HRs of the PNI for survival outcomes were not statistically significant. Overall, age, sex, tumor-node-metastasis (TNM) stage, pleural invasion (PI), and GNRI were significant determinants of OS and constituted the OS model (concordance index [C-index], 0.824). In addition, age, TNM stage, PI, and GNRI were significant determinants of CSS and constituted the CSS model (C-index, 0.828). Finally, TNM stage, PI, lymphatic invasion, and GNRI were significant determinants of RFS and constituted the RFS model (C-index, 0.783). Our study showed that GNRI, but not PNI, was a predictor of OS, CSS, and RFS in patients with stage I-III NSCLC across all age groups. Excellent discriminant power was observed for OS, CSS, and RFS models.

Distinct Prognostic Factors of Ground Glass Opacity and Pure-Solid Lesion in Pathological Stage I Invasive Lung Adenocarcinoma

BACKGROUND

Ground glass opacity (GGO) is associated with favorable survival in lung cancer. However, the relevant evidence of the difference in prognostic factors between GGO and pure-solid nodules for pathological stage I invasive adenocarcinoma (IAC) is limited. We aimed to identify the impact of GGO on survival and find prognostic factor for part-GGO and pure-solid patients.

METHODS

Between December 2007 and August 2018, patients with pathological stage I IAC were retrospectively reviewed and categorized into the pure-GGO, part-GGO, and pure-solid groups. Survival curves were analyzed by the Kaplan-Meier method and compared by log-rank tests. Least absolute shrinkage and selection operator and Cox regression models were used to obtained prognostic factors for disease-free survival (DFS) and overall survival (OS).

RESULTS

The number of patients with pure-GGO, part-GGO, and pure-solid was 134, 540, and 396, respectively. Part-GGO patients with consolidation-tumor-ratio (CTR) > 0.75 had similar outcome to those with pure-solid nodules. In part-GGO patients, CTR was negatively associated with OS (P = 0.007) and solid tumor size (STS) was negatively associated with DFS (P < 0.001). Visceral pleural invasion (VPI) was negatively associated with OS (P = 0.040) and DFS (P = 0.002). Sublobectomy was negatively associated with OS (P = 0.008) and DFS (P = 0.005), while extended N1 stations examination was associated with improved DFS (P = 0.005) in pure-solid patients.

CONCLUSIONS

Though GGO component is a positively prognostic factors of patients with pathological stage I IAC, a small proportion of GGO components is not associated with favorable survival. VPI, STS and CTR are the significant predictors for part-GGO patients. Sublobectomy, especially wedge resection should be used cautiously in pure-solid patients.

Rethinking the Selection of Pathological T-Classification for Non-Small-Cell Lung Cancer in Varying Degrees of Visceral Pleural Invasion: A SEER-Based Study

Background

The T classification of non-small-cell lung cancer (NSCLC) was upgraded from T1 to T2 when accompanied by visceral pleural invasion (VPI). However, the association between VPI and prognostic outcomes was obscure in NSCLC patients with ≤3 cm tumor size (TS), which leaded the controversy of selection of T classification. The goal was to evaluate the effect of VPI on the prognosis of NSCLC with ≤ 3cm TS and present a modified T classification.

Methods

A total of 14,934 NSCLC patients without distant metastasis were recruited through a retrospective study in the SEER database. The effect of VPI on lung cancer specific survival (LCSS) was evaluated using survival curve and COX regression analysis in NSCLC patients with ≤3 cm TS.

Results

Although there was no difference of the LCSS of PL0 and PL1 patients with ≤2 cm TS in patients without lymph node (LN) metastasis, the LCSS was lower in PL2 patients than those in PL0 (T1a: p < 0.001; T1b: p = 0.001). Moreover, the LCSS was decreased in PL1 and PL2 patients with 2-3 cm TS compared with PL0 (T1c: PL1, p < 0.001; PL2, p = 0.009) of patients without LN metastasis. No difference of LCSS was observed in patients with LN metastasis between PL0 with PL1 and PL2.

Conclusion

In NSCLC patients without LN metastasis and TS ≤ 2 cm, tumor with PL1 should remain defined as T1, tumor with PL2 should be defined as T2. However, 2-3 cm TS patients with PL1 or PL2 should both defined as T2. Meanwhile, ≤3 cm TS patients with LN metastasis can be regarded as T1, whether NSCLC patients accompanied with PL1 or PL2.

Is lobectomy superior to sub-lobectomy in non-small cell lung cancer with pleural invasion? A population-based competing risk analysis

Background

Pleural invasion (PL) has been regarded as an unfavorable prognostic factor for non-small cell lung cancer (NSCLC). But there was no agreement on the optimal surgical extent in NSCLC patients with PL. We aimed to compare the survival outcomes of lobectomy and sub-lobectomy in these patients.

Method

2717 patients were included in the Surveillance, Epidemiology, and End Results (SEER) database and divided into the lobectomy and sub-lobectomy groups. The propensity score matching (PSM) and competing risk analysis were implemented. Then the predictive nomogram was constructed and validated.

Results

2230 Patients received lobectomy while the other 487 patients underwent sub-lobectomy. After 1:1 PSM, the cumulative incidence of cancer-specific death (CSD) was lower in the lobectomy group compared with the sub-lobectomy group (1-year: 12% vs. 15%; 3-year: 30% vs. 37%, 5-year: 34% vs. 45%, P = 0.04). According to the subgroup analysis, the patients who underwent lobectomy suffered lower CSD in the N0–1 stage, adenocarcinoma, and PL-2 cohort (p < 0.05). And there was a significant relationship between the sub-lobectomy group and CSD in the multivariate competing risks regression analysis (HR, 1.26; 95%CI, 1.02–1.56; P = 0.034). Furthermore, a competing event nomogram was constructed to assess the 1-, 3-, and 5-year chances of CSD based on the variables from the multivariate analysis. The 1-, 3-, 5-year area under the receiver operating characteristic curve (AUC) values were 0.720, 0.706, and 0.708 in the training cohort, and 0.738, 0.696, 0.680 in the validation cohorts, respectively. And calibration curves demonstrated ideal consistency between the predicted and observed probabilities of CSD.

Conclusion

Lobectomy should be considered the preferred surgery compared to sub-lobectomy for NSCLC patients with PL. The proposed nomograms presented great prediction ability for these patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09634-w.

Non-small Cell Lung Cancer Surpassing the Elastic Layer Should Remain Classified as pT2a

We aimed to evaluate the prognostic value of visceral pleural invasion on the survival of node-negative non-small cell lung cancer ≤3 cm using a large cohort. The Kaplan-Meier method was used to compare overall survival (OS); competing risk analysis with Fine-Gray's test was used to compare cancer- specific survival between groups. The least absolute shrinkage and selection operator penalized Cox regression model was used to identify prognostic factors. In total, 9725 eligible cases were included in this study, and they were separated into 3 groups: tumor invasion beneath the elastic layer (PL0), 8837 cases; tumor invasion surpassing the elastic layer (PL1), 505 cases; and tumor invasion to the visceral pleural surface (PL2), 383 cases. Visceral pleural invasion was more likely to occur in poorly differentiated and larger-sized tumors. Survival curves displayed that PL0 conferred better survival rates than PL1 and PL2, and PL1 achieved outcomes equivalent to those of PL2. Tumor size and histology subset analyses further corroborated this conclusion. Least absolute shrinkage and selection operator -penalized Cox regression analysis confirmed that PL status was an independent prognostic factor for both OS and cancer- specific survival. This study supported the notion that in node-negative non-small cell lung cancer ≤3 cm, PL1 patients should remain classified as pT2a, which could improve staging accuracy.

Prognostic significance of visceral pleural invasion in patients with surgically resected small-cell lung cancer: a population-based study

OBJECTIVE

Visceral pleural invasion is an adverse prognostic factor in non-small-cell lung cancer, but its value in small-cell lung cancer remains unclear. Thus, we investigated the prognostic impact of visceral pleural invasion in patients with surgically resected small-cell lung cancer.

METHODS

We queried the Surveillance, Epidemiology and End Results Program database for patients diagnosed with stages I-III (excluding N3 and nodal metastasis cannot be evaluated (NX)) small-cell lung cancer from 2004 to 2016, who underwent surgery. To minimize unbalanced baseline characteristics between the visceral pleural invasion and non-visceral pleural invasion groups, one-to-one propensity score matching was employed. A Kaplan-Meier curve was used to compare the overall survival of the two cohorts. A Cox proportional hazards model was adopted to determine the impact of visceral pleural invasion on survival.

RESULTS

Of the 1416 patients included, 372 (26.27%) presented with visceral pleural invasion. Patients with visceral pleural invasion showed significantly worse overall survival (P < 0.001) both before and after propensity score matching. Multivariable analysis indicated that visceral pleural invasion was an independent adverse factor affecting survival. Patients with visceral pleural invasion showed poorer overall survival (hazard ratio: 1.44; 95% confidence interval: 1.17-1.76; P < 0.001). Subgroup analyses revealed that the non-visceral pleural invasion group was associated with favourable overall survival in N0 patients (P = 0.003) but not in N1 or N2 patients (P = 0.774 and 0.248, respectively). Patients diagnosed at younger ages, females, lower N stage, resection with a lobectomy and adjuvant chemotherapy were associated with improved overall survival in the visceral pleural invasion group.

CONCLUSIONS

Visceral pleural invasion was an indicator of a poor prognosis for small-cell lung cancer, especially in those with N0 disease. Adjuvant chemotherapy significantly improves patient outcomes for patients with visceral pleural invasion.

Treatment Modality for Stage IB Peripheral Non-Small Cell Lung Cancer With Visceral Pleural Invasion and ≤3 cm in Size

Purpose

To compare the survival difference among lobectomy, segmentectomy, and wedge resection and investigate the role of adjuvant chemotherapy for early-stage small-sized non-small cell lung cancer (NSCLC) with visceral pleural invasion (VPI).

Methods

Patients diagnosed with stage IB peripheral NSCLC with VPI and ≤3 cm in size in the Surveillance, Epidemiology, and End Results database between 2004 and 2015 were included, and the pleural layer (PL) invasion status was identified to recognize the tumors with VPI, including PL1 and PL2. We conducted Cox proportional hazards model in multivariable analysis and subgroup analysis via propensity score matching (PSM) method and Cox regression method to figure out the optimal therapy for these patients.

Results

A total of 1,993 patients were included, all of whom received surgery, and the median follow-up was 33 months (range, 1–83 months). In multivariable analysis, age, gender, histology, pathological grade, lymph node examination, surgical approaches, and radiotherapy were independent prognostic factors for overall survival (OS). Lobectomy was superior to sublobar resection [hazard ratio (HR) = 1.41; 95% CI, 1.08–1.83], and wedge resection was associated with impaired survival compared to lobectomy (HR = 1.64; 95% CI, 1.22–2.20) in PSM analyses. In subgroup analysis, lobectomy was superior to sublobar resection among those aged <70 years (HR = 1.81; 95% CI, 1.13–2.90), female (HR = 1.75; 95% CI, 1.21–2.53), and 1–20 mm in size (HR = 1.61; 95% CI, 1.11–2.33). No survival benefit was observed for adjuvant chemotherapy.

Conclusions

Lobectomy was superior to wedge resection and comparable with segmentectomy for stage IB NSCLC (≤3 cm) with VPI, and adjuvant chemotherapy could not benefit these patients, even in those with sublobar resection. The preferred surgical procedure remains to be studied in prospective controlled trials.

Oncological outcome of segmentectomy for early-stage non-small-cell lung cancer with invasive characteristics: a multicentre study

OBJECTIVES

Segmentectomy can provide oncologically acceptable results for small-sized non-small-cell lung cancer (NSCLC). However, in cases of NSCLC with pathological invasive characteristics such as lymphatic invasion (LY), vascular invasion (V), pleural invasion (PL) and/or lymph node metastasis, the feasibility of segmentectomy is not known.

METHODS

The patients included in the study (i) underwent lobectomy or segmentectomy for NSCLC with invasive characteristics such as LY, V, PL or pathological lymph node metastasis; (ii) presented with a node-negative, solid component-predominant tumour (consolidation tumour ratio >50%) on preoperative computed tomography; (iii) had a whole-tumour size of 2 cm or less; and (iv) presented between January 2010 and December 2019 to one of the 3 institutions. Cumulative incidences of recurrence (CIRs) after segmentectomy and lobectomy were compared.

RESULTS

A total of 321 patients were included. Segmentectomy and lobectomy were performed in 80 (24.9%) and 241 (75.1%) patients, respectively. There was no significant difference in CIR between segmentectomy (5-year CIR rate, 17.2%) and lobectomy patients (5-year CIR rate, 27.8%, P = 0.135). In the propensity score-matched cohort, there was no significant difference in CIR between segmentectomy (5-year CIR rate, 19.1%) and lobectomy patients (5-year CIR rate, 19.2%; P = 0.650). In the multivariable analysis using inverse probability of treatment weighting and surgical method, segmentectomy was not a significant predictor of worse CIR (P = 0.920).

CONCLUSIONS

Segmentectomy is feasible for clinically early-stage NSCLC irrespective of the presence of LY, V, PL or lymph node metastasis.

Decreased sphingomyelin (t34:1) is a candidate predictor for lung squamous cell carcinoma recurrence after radical surgery: a case-control study

Background

To reduce disease recurrence after radical surgery for lung squamous cell carcinomas (SQCCs), accurate prediction of recurrent high-risk patients is required for efficient patient selection for adjuvant chemotherapy. Because treatment modalities for recurrent lung SQCCs are scarce compared to lung adenocarcinomas (ADCs), accurately selecting lung SQCC patients for adjuvant chemotherapy after radical surgery is highly important. Predicting lung cancer recurrence with high objectivity is difficult with conventional histopathological prognostic factors; therefore, identification of a novel predictor is expected to be highly beneficial. Lipid metabolism alterations in cancers are known to contribute to cancer progression. Previously, we found that increased sphingomyelin (SM)(d35:1) in lung ADCs is a candidate for an objective recurrence predictor. However, no lipid predictors for lung SQCC recurrence have been identified to date. This study aims to identify candidate lipid predictors for lung SQCC recurrence after radical surgery.

Methods

Recurrent (n = 5) and non-recurrent (n = 6) cases of lung SQCC patients who underwent radical surgery were assigned to recurrent and non-recurrent groups, respectively. Extracted lipids from frozen tissue samples of primary lung SQCC were analyzed by liquid chromatography-tandem mass spectrometry. Candidate lipid predictors were screened by comparing the relative expression levels between the recurrent and non-recurrent groups. To compare lipidomic characteristics associated with recurrent SQCCs and ADCs, a meta-analysis combining SQCC (n = 11) and ADC (n = 20) cohorts was conducted.

Results

Among 1745 screened lipid species, five species were decreased (≤ 0.5 fold change; P < 0.05) and one was increased (≥ 2 fold change; P < 0.05) in the recurrent group. Among the six candidates, the top three final candidates (selected by AUC assessment) were all decreased SM(t34:1) species, showing strong performance in recurrence prediction that is equivalent to that of histopathological prognostic factors. Meta-analysis indicated that decreases in a limited number of SM species were observed in the SQCC cohort as a lipidomic characteristic associated with recurrence, in contrast, significant increases in a broad range of lipids (including SM species) were observed in the ADC cohort.

Conclusion

We identified decreased SM(t34:1) as a novel candidate predictor for lung SQCC recurrence. Lung SQCCs and ADCs have opposite lipidomic characteristics concerning for recurrence risk.

Trial registration

This retrospective study was registered at the UMIN Clinical Trial Registry (UMIN000039202) on January 21, 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08948-5.

Diagnosis of visceral pleural invasion using confocal laser endomicroscopy during lung cancer surgery

Background

Visceral pleural invasion (VPI) in lung cancer is a significant prognostic factor; however, it is difficult to diagnose preoperatively or intraoperatively. In this study, we examined the possibility of intraoperative diagnosis of VPI using confocal laser endomicroscopy (CLE).

Methods

Among patients with primary lung cancer who underwent surgery between April 2018 and August 2019, those in whom the tumor was in contact with the pleura on chest computed tomography and whose pleural changes were intraoperatively confirmed were enrolled in this study. In the 35 patients who underwent lung resection (6 cases with visceral pleural infiltration), the area where pleural change was noted was observed and a short video was recorded using CLE. Based on the video images, three evaluators determined the defect ratio (0%, 25%, 50%, 75%, and 100%) of the autofluorescence-positive structure. The area under the receiver operating characteristic curve was used to evaluate the diagnostic performance for VPI. In 15 cases (3 cases with VPI), a validation study was performed for intraoperative VPI according to the cutoff value of the defect ratio of the autofluorescence-positive structure.

Results

The areas under the receiver operating characteristic curve for the defect ratio of the autofluorescence-positive structure were 0.86–0.91 for the three readers. Using defect ratio of autofluorescence-positive structure cutoff of ≥50% as predictor of VPI, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 83.3–100.0%, 57.7–73.1%, 35.3–41.7%, 95.0–100.0%, and 75.0–78.1%, respectively, for the three readers. In the validation study, the sensitivity was 100%, the specificity was 83.3%, and the diagnostic accuracy rate was 86.7%.

Conclusions

The diagnosis of VPI through CLE is simple, non-invasive, and has high diagnostic accuracy rates. This method may be applicable for determining surgical procedures.

Modification of Pathologic T Classification for Non-small Cell Lung Cancer With Visceral Pleural Invasion: Data From 1,055 Cases of Cancers ≤ 3 cm

BACKGROUND

Visceral pleural invasion (VPI) with PL1 or PL2 increases the T classification from T1 to T2 in non-small cell lung cancers (NSCLCs) ≤ 3 cm. We proposed a modified T classification based on VPI to guide adjuvant therapy.

RESEARCH QUESTION

Is it reasonable to upstage PL1-positive cases from T1 to T2 for NSCLCs ≤ 3 cm?

STUDY DESIGN AND METHODS

In total, 1,055 patients with resected NSCLC were retrospectively included. Tumor sections were restained with hematoxylin and eosin stain and Victoria blue elastic stain for the elastic layer. Disease-free survival (DFS) and overall survival (OS) were calculated by the Kaplan-Meier method. Subgroup analysis and a Cox proportional hazards model were used to further determine the impact of VPI on survival.

RESULTS

The extent of VPI was diagnosed as PL0 in 824 patients, PL1 in 133 patients, and PL2 in 98 patients. The 5-year DFS rates of patients with PL0, PL1, and PL2 were 62.6%, 60.2%, and 28.8% (P < .01), whereas the corresponding 5-year OS rates were 78.6%, 74.4%, and 50.0% (P < .01), respectively. As predicted, the DFS and OS of patients with PL2 were much worse than those of patients with PL0 (P < .01) and PL1 (P < .01). However, both the DFS and OS of patients with PL0 and PL1 were comparable (DFS: P = .198; OS: P = .150). For node-negative cases, the DFS and OS of patients with PL0 and PL1 were also comparable (DFS: P = .468; OS: P = .388), but patients with PL2 had much worse DFS and OS than patients with PL0 (P < .01) and PL1 (P < .01). Multivariable analyses suggested that PL2, together with node positivity and poor cell differentiation, was an independent adverse prognostic factor.

INTERPRETATION

In NSCLCs ≤ 3 cm, tumors with PL1 should remain defined as T1, not T2. Overtreatment by adjuvant chemotherapy in node-negative NSCLCs ≤ 3 cm might be avoided in PL1 cases.

The modification of T description according to visceral pleural invasion and tumor size from 3.1 cm to 4.0 cm in non-small cell lung cancer: A retrospective analysis based on the SEER database

OBJECTIVES

As a poor prognostic factor, visceral pleural invasion (VPI) was incorporated into non-small cell lung cancer (NSCLC) staging system. For modifying the T description of NSCLC, the prognostic value of VPI was assessed.

MATERIALS AND METHODS

From 2010-2015, data on stage pT2N0M0 NSCLC patients with tumor size (TS) from 3.1 cm to 5.0 cm who received surgery from the Surveillance, Epidemiology, and End Results (SEER) database were enrolled retrospectively. Propensity score matching was utilized to balance the baseline factors according to different TS intervals. Overall survival (OS) was assessed by the Kaplan-Meier method and log-rank test. Univariate and multivariate analysis were applied to identify the prognostic factors. The risk factors of VPI were calculated by logistic regression model.

RESULT

The sum of 4005 resected stage pT2N0M0 NSCLC patients with TS from 3.1 cm to 5.0 cm were recruited, which had 1084 patients with VPI and 2921 patients without VPI respectively. As TS interval of 3.1-4.0 cm, the 5-year OS of patients without VPI was significantly better than those with VPI (62.6 % vs 58.7 %, P = 0.015), while the 5-year OS of patients with VPI and TS interval of 3.1-4.0 cm had no significant difference compared with patients whose TS interval of 4.1-5.0 cm (58.7 % vs 58.8 %, P = 0.918). Logistic regressive analysis manifested that older age, female, worse differentiation grade and larger TS had higher incidence of VPI (OR = 1.01, 1.25, 1.25, 1.16, respectively; P < 0.05 for all).

CONCLUSION

This study underlined the prognostic effect of VPI and suggested that early-stage NSCLC with VPI and TS interval of 3.1-4.0 cm could be appropriately upstaged from pT2a (stage pIB) to pT2b (modified stage pIIA).

Clinical significance of C-Reactive Protein to Lymphocyte Count Ratio as a prognostic factor for Survival in Non-small Cell Lung Cancer Patients undergoing Curative Surgical Resection

Purpose: We assessed the clinical feasibility of C-reactive protein to lymphocyte ratio (CLR) as a determinant of survival in patients with non-small cell lung cancer (NSCLC) undergoing curative surgical resection. Methods: A retrospective study was conducted on patients with stage I and II NSCLC undergoing curative resection. Demographic and clinical variables, including CLR, were collected and analyzed. The Cox proportional hazards model was used to calculate hazard ratios for overall survival (OS) and cancer-specific survival (CSS). The Mann-Whitney U test was used to compare differences between two independent groups. Results: The median age of the patients was 69.0 years, and male patients comprised 63.9% of all patients. A total of 164 (75.9%) patients were categorized as having stage I disease and 52 (24.1%) as having stage II disease. Using the multivariate Cox model, age (hazard ratio [HR] 1.08, p<0.001), lymphatic invasion (HR 3.12, p=0.004), stage (HR 5.10, p<0.001), and CLR (HR 1.01, p=0.003) were significant determinants of OS. In addition, age (HR 1.11, p=0.002), lymphatic invasion (HR 3.16, p=0.010), stage (HR 6.89, p<0.001), and CLR (HR 1.05, p=0.002) were significant determinants of CSS. Conclusions: Our findings show that CLR could be a determinant of survival in NSCLC patients undergoing curative surgical resection.

Nomogram for Predicting the Relationship between the Extent of Visceral Pleural Invasion and Survival in Non-Small-Cell Lung Cancer

Objective

Although visceral pleural invasion (VPI) has already been incorporated into the TNM staging system, few studies have been conducted to evaluate the prognostic value of the extent of VPI for the survival of non-small-cell lung cancer (NSCLC) patients. Thus, we utilized the Surveillance, Epidemiology, and End Results (SEER) database to assess the correlation between the extent of VPI and survival in NSCLC.

Methods

We identified and incorporated the extent of VPI to build a prognostic nomogram in this study. Patients in the SEER database diagnosed with NSCLC (n = 87,045) from 2010 to 2015 were further analyzed and randomly assigned into either the training group (n = 60,933) or validation group (n = 26,112). Clinical variables were calculated by means of multivariate Cox regressions and incorporated into the predictive model. Subsequently, the accuracy and discrimination of nomogram were further assessed through the concordance index (C-index), calibration curves, and Kaplan–Meier curves.

Results

Multivariate analysis demonstrated that the extent of visceral pleural invasion was an independent and unfavorable prognostic factor. The C-indexes of the training and validation groups were 0.772 (95% CI: 0.770–0.774) and 0.769 (95% CI: 0.765–0.773), respectively, which revealed that the nomogram had sufficient credibility and stable predictive accuracy. The calibration curve displayed consistency between the actual and predictive values in both training and validation groups.

Conclusion

The prognostic nomogram with the extent of VPI could offer an accurate risk evaluation for patients with NSCLC. Independent external validation of this research should be conducted in the future.

Recognition of filigree pattern expands the concept of micropapillary subtype in patients with surgically resected lung adenocarcinoma

Our study aimed to validate the clinicopathological characteristics and prognosis of lung adenocarcinoma (ADC) with a filigree pattern and to further investigate the relationship between the filigree pattern and the classical micropapillary (MP) pattern. We retrospectively reviewed the clinical and pathologic characteristics of 461 Chinese patients with completely resected ADC (stage I, 310; stage II, 44; stage III, 107). The filigree pattern was more likely to be observed in ADC with a higher stage (p = 0.003) and the classical MP pattern (p < 0.001). Patients with filigree-predominant ADC showed poor survival, similar to those with classical MP-predominant ADC. Multivariate analysis confirmed that the presence of the filigree pattern was an independent prognostic factor for recurrence-free survival (hazard ratio (HR), 2.01; 95% confidence interval (CI), 1.50-2.68; p < 0.001) and overall survival (OS; HR, 1.83; 95% CI, 1.34-2.50; p < 0.001). Patients with both classical MP-positive and filigree-positive ADC had the worst survival compared with those with the filigree pattern or classical MP pattern alone. In stage I, ADC with both the filigree and classical MP patterns had a higher incidence of micrometastasis than ADC with the filigree pattern or classical MP pattern alone. Lymph node micrometastasis indicated poor survival in patients with ADC with the filigree pattern or classical MP pattern. Similar clinicopathologic features between patients with the filigree pattern and the classical MP pattern support the inclusion of the filigree pattern in the MP category. Recognition of the filigree pattern could provide helpful prognostic information, especially for stage I ADC.

Glutathione Peroxidase 3 as a Biomarker of Recurrence after Lung Cancer Surgery

We aimed to examine the usefulness of serum glutathione peroxidase 3 (GPx3) as a biomarker of lung cancer recurrence after complete resection. We prospectively collected serial serum samples at the baseline, as well as 3, 6 and 12 months after surgery from complete resection cases in 2013. GPx3 levels were measured by enzyme-linked immunosorbent assay. Statistical tests including t-tests and Cox proportional hazard regression analyses were performed. Totally, 135 patients were enrolled, and 39 (28.9%) showed relapse during the median follow-up period (63.60 months; range, 0.167–81.867). The mean GPx3 change was significantly higher in the recurrence group at 6 months (0.32 ± 0.38 vs. 0.15 ± 0.29, p = 0.016) and 12 months (0.40 ± 0.37 vs. 0.13 ± 0.28, p = 0.001). The high GPx3 change group showed significantly higher 60-months recurrence rates than the low group (48.1% vs. 25.2% at 3 months, p = 0.005; 54.5% vs. 28.9% at 6 months, p = 0.018; 38.3% vs. 18.3% at 12 months, p = 0.035). High GPx3 change at 3 months were independent risk factors of recurrence (hazard ratio (HR) 3.318, 95% confidence interval (CI), 1.582–6.960, p = 0.002) and survival (HR 3.150, 95% CI, 1.301–7.628, p = 0.011). Therefore, serum GPx3 changes after surgery may be useful predictive biomarkers for recurrence in lung cancer. Larger-scale validation studies are warranted to confirm these findings.

Sphingomyelin(d35:1) as a novel predictor for lung adenocarcinoma recurrence after a radical surgery: a case-control study

Background

To improve the postoperative prognosis of patients with lung cancer, predicting the recurrence high-risk patients is needed for the efficient application of adjuvant chemotherapy. However, predicting lung cancer recurrence after a radical surgery is difficult even with conventional histopathological prognostic factors, thereby a novel predictor should be identified. As lipid metabolism alterations are known to contribute to cancer progression, we hypothesized that lung adenocarcinomas with high recurrence risk contain candidate lipid predictors. This study aimed to identify candidate lipid predictors for the recurrence of lung adenocarcinoma after a radical surgery.

Methods

Frozen tissue samples of primary lung adenocarcinoma obtained from patients who underwent a radical surgery were retrospectively reviewed. Recurrent and non-recurrent cases were assigned to recurrent (n = 10) and non-recurrent (n = 10) groups, respectively. Extracted lipids from frozen tissue samples were subjected to liquid chromatography-tandem mass spectrometry analysis. The average total lipid levels of the non-recurrent and recurrent groups were compared. Candidate predictors were screened by comparing the folding change and P-value of t-test in each lipid species between the recurrent and non-recurrent groups.

Results

The average total lipid level of the recurrent group was 1.65 times higher than that of the non-recurrent group (P < 0.05). A total of 203 lipid species were increased (folding change, ≥2; P < 0.05) and 4 lipid species were decreased (folding change, ≤0.5; P < 0.05) in the recurrent group. Among these candidates, increased sphingomyelin (SM)(d35:1) in the recurrent group was the most prominent candidate predictor, showing high performance of recurrence prediction (AUC, 9.1; sensitivity, 1.0; specificity, 0.8; accuracy, 0.9).

Conclusion

We propose SM(d35:1) as a novel candidate predictor for lung adenocarcinoma recurrence. Our finding can contribute to precise recurrence prediction and qualified postoperative therapeutic strategy for lung adenocarcinomas.

Trial registration

This retrospective study was registered at the UMIN Clinical Trial Registry (UMIN000039202) on 21st January 2020.

Management of Ground-Glass Opacities in the Lung Cancer Spectrum

BACKGROUND

Along with the popularity of low-dose computed tomography lung cancer screening, an increasing number of lung ground-glass opacity (GGO) lesions are detected. This review focuses on lung adenocarcinoma manifesting as GGO.

METHODS

We performed a literature search of the PubMed/MEDLINE database to identify articles reporting GGO. The following terms were used: GGO, ground-glass opacity, GGN, ground-glass nodule, part-solid nodule, and subsolid nodule.

RESULTS

GGO is a nonspecific radiologic finding showing a hazy opacity without blocking underlying pulmonary vessels or bronchial structures. The pathology of GGO can be benign, preinvasive, or invasive adenocarcinoma. Although radiographic features may indicate malignancy, a short period of follow-up is the optimal method to distinguish between benign and malignant GGO lesions. Pathologically, not only lepidic, but also nonlepidic growth patterns can present as GGO. Lung adenocarcinoma with a GGO component is associated with excellent survival compared with solid lesions. Moreover, there are distinct prognostic factors in patients with lung adenocarcinoma manifesting as GGO or solid lesions. For selected GGO-featured lung adenocarcinoma, sublobar resection with selective or no mediastinal lymph node dissection may be sufficient. Intraoperative frozen section is an effective method to guide resection strategy. A less intensive postoperative surveillance strategy may be more appropriate given the excellent survival. Management of multiple GGO lesions requires comprehensive considerations of GGO characteristics and patient conditions.

CONCLUSIONS

Lung adenocarcinoma manifesting as GGO defines a special clinical subtype with excellent prognosis. The management of GGO-featured lung adenocarcinoma should be distinct from that of solid lesions.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Complex Network Characterization Using Graph Theory and Fractal Geometry: The Case Study of Lung Cancer DNA Sequences

This paper discusses an approach developed for exploiting the local elementary movements of evolution to study complex networks in terms of shared common embedding and, consequently, shared fractal properties. This approach can be useful for the analysis of lung cancer DNA sequences and their properties by using the concepts of graph theory and fractal geometry. The proposed method advances a renewed consideration of network complexity both on local and global scales. Several researchers have illustrated the advantages of fractal mathematics, as well as its applicability to lung cancer research. Nevertheless, many researchers and clinicians continue to be unaware of its potential. Therefore, this paper aims to examine the underlying assumptions of fractals and analyze the fractal dimension and related measurements for possible application to complex networks and, especially, to the lung cancer network. The strict relationship between the lung cancer network properties and the fractal dimension is proved. Results show that the fractal dimension decreases in the lung cancer network while the topological properties of the network increase in the lung cancer network. Finally, statistical and topological significance between the complexity of the network and lung cancer network is shown.

Clinicopathological features of small-sized peripheral squamous cell lung cancer

Recent advances in imaging technology have enhanced the detection rate of small-sized peripheral lung cancers. The present study aimed to identify the clinicopathological differences between patients with small-sized peripheral squamous cell carcinoma (SCC) and adenocarcinoma (ADC). Patients with lung cancer who underwent radical surgical resection at Gunma University Hospital between July 2007 and October 2012 were retrospectively analyzed. Patients who exhibited small-sized peripheral tumors (pathological size, ≤2 cm) located within the outer-third of the lung field on preoperative computed tomography were enrolled in the present study. A total of 26 patients were diagnosed with SCC and 214 with ADC. The results revealed that patients with SCC exhibited higher rates of pleural invasion, vascular invasion and lymphatic invasion compared with ADC patients. Additionally, the rate of postoperative recurrence was higher in patients with SCC compared with ADC patients. Patients with ADC were subsequently into two groups: Solid ADCs (sADC) and non-solid ADCs (nsADC), which included pure ground glass nodules and part-solid ADCs. The results revealed that the incidence of pleural invasion, vascular invasion and lymphatic invasion, and the rate of postoperative recurrence in patients with sADCs were similar to those with SCC, but were also significantly higher when compared with nsADC patients. The present study concluded that patients with SCC and sADC may not be suitable candidates for sublobar resection, despite exhibiting small tumors that are located in the peripheral lung.

Distinct Prognostic Factors in Patients with Stage I Non-Small Cell Lung Cancer with Radiologic Part-Solid or Solid Lesions

INTRODUCTION

Recent studies have indicated that the presence of ground-glass opacity (GGO) components is associated with favorable survival. The purpose of this study was to reveal the prognostic value of GGO components and differences in prognostic factors for part-solid and solid lesions in invasive stage I NSCLC.

METHODS

The cases of 2010 patients with completely resected invasive pathological stage I NSCLC were reviewed according to the eighth edition of the TNM classification. Patients were categorized into the pure-GGO, part-solid, and solid groups based on consolidation-to-tumor ratio. Cox multivariate proportional hazard analyses were conducted to identify independent prognostic factors in each group.

RESULTS

Of the 2010 patients, 146 (7.3%) were in the pure-GGO group, 732 (36.4%) were in the part-solid group, and 1132 (56.3%) were in the solid group. Cox multivariate analyses revealed that GGO absence was a strong independent risk factor for worse recurrence-free survival (p < 0.001). For the pure-GGO group, there was no recurrence in spite of the invasive stage. For the part-solid group, visceral pleural invasion could not predict recurrence-free survival in general (p = 0.514) or in each tumor size group (for tumors size ≤1 cm, p = 0.664; for tumors size >1 to 2 cm, p = 0.456; for tumors size >2 to 3 cm, p = 0.900; and for tumors size >3 to 4 cm, p = 0.397). For the solid group, adenocarcinoma subtype was not a prognostic factor for recurrence-free survival in general (p = 0.162) or in each tumor size group (for tumors size ≤ 2 cm, p = 0.092; for tumors size >2 to 3 cm, p = 0.330; and for tumors size >3 to 4 cm, p = 0.885).

CONCLUSIONS

The presence of GGO components was a strong predictor in patients with invasive pathological stage I NSCLC. Risk factors were distinct in the part-solid and solid groups. There was no prognostic value of visceral pleural invasion in the part-solid group. Adenocarcinoma subtype did not have prognostic value in the solid group.

Visceral Pleural Invasion in Pulmonary Adenocarcinoma: Differences in CT Patterns between Solid and Subsolid Cancers

PURPOSE

To analyze the incidence and CT patterns of visceral pleural invasion (VPI) in adenocarcinomas on the basis of their CT presentation as solid or subsolid nodules.

MATERIALS AND METHODS

A total of 286 adenocarcinomas in direct contact with a pleural surface, resected at an institution between 2005 and 2016, were included in this retrospective, institutional review board-approved study. CT size and longest contact length with a pleural surface were measured and their ratios computed. Pleural deviation, pleural thickening, spiculations, different pleural tag types, pleural effusion, and the CT appearance of transgression into an adjacent lobe or infiltration of surrounding tissue were evaluated. Fisher exact tests and simple and multiple logistic regression models were used.

RESULTS

Of the 286 nodules, 179 of 286 (62.6%) were solid and 107 of 286 (37.4%) were subsolid. VPI was present in 49 of 286 (17.1%) nodules and was significantly more frequent in solid (44 of 179; 24.6%) than in subsolid nodules (five of 107; 4.7%; P < .001). In solid nodules, multiple regression analysis showed an association of higher contact length-to-size ratio (adjusted odds ratio [OR], 1.02; P = .007) and the presence of multiple pleural tag types (adjusted OR, 5.88; P = .002) with VPI. In subsolid nodules, longer pleural contact length of the solid nodular component (adjusted OR, 1.27; P = .017) and the CT appearance of transgression or infiltration (adjusted OR, 10.75; P = .037) were associated with VPI.

CONCLUSION

During preoperative evaluation of adenocarcinomas for the likelihood of VPI, whether a tumor manifests as a solid or a subsolid nodule is important to consider because the incidence of VPI is significantly higher in solid than in subsolid nodules. In addition, this study showed that the CT patterns associated with VPI differ between solid and subsolid nodules.© RSNA, 2019Supplemental material is available for this article.See also the commentary by Elicker in this issue.

Validation of the 8th edition of the TNM staging system in 3,950 patients with surgically resected non-small cell lung cancer

BACKGROUND

The International Association for the Study of Lung Cancer introduced the 8th edition of the tumor, node, and metastasis (TNM) staging system for lung cancer. In this study, we validated the 8th edition of the TNM staging system and compared its discrimination power with that of the previous 7th edition.

METHODS

A retrospective analysis was carried out on patients who underwent complete resection with systematic lymph node dissection for non-small cell lung cancer (NSCLC) between 2006 and 2015 at a tertiary referral center in Seoul, South Korea. Cox regression model was used to identify significant differences between adjacent TNM stage groupings. The Concordance index (C-index), Akaike Information Criterion (AIC), and R2 measure were utilized to evaluate the discrimination ability of the staging systems.

RESULTS

A total of 3,950 patients (2,440 male, median age: 63 years) were analyzed. Median follow-up was 59 months (interquartile ranges, 38-88 months). According to the 8th edition, survival curves of overall survival (OS) and recurrence-free survival (RFS) within adjacent stage groupings showed significant differences except for IIA vs. IIB. Compared with the 7th edition, the 8th edition showed higher C-index (0.753 vs. 0.751), lower AIC (17,517 vs. 17,543), and higher R2 (0.178 vs. 0.171) values, indicating better discrimination ability.

CONCLUSIONS

Stratification based on the 8th edition of the TNM staging system showed favorable prognostic validity compared with the 7th edition. The 8th edition also had superior discrimination ability in terms of OS and RFS.

Visceral pleural invasion in T1 tumors (≤3 cm), particularly T1a, in the eighth tumor-node-metastasis classification system for non-small cell lung cancer: a population-based study

BACKGROUND

We aimed to validate the tumor (T) descriptors of visceral pleural invasion (VPI) for T1 tumors (<3 cm) in the 8th edition of the tumor-node-metastasis (TNM) classification system and the prognostic value of VPI for resected T1a tumors.

METHODS

The external cohort consisted of 23,501 patients with resected pN0 non-small cell lung cancer (NSCLC) selected from the Surveillance, Epidemiology, and End Results (SEER) database (2010 to 2013). The classification of T1 tumors with VPI was investigated using survival curves. The internal cohort consisted of patients diagnosed with pN0 NSCLC between 2011 and 2013 at Guangdong Lung Cancer Institute. The prognostic value of VPI for T1a tumors (<1 cm) was further assessed in these two cohorts.

RESULTS

The overall survival (OS) and lung cancer-specific survival (LCSS) of the T1-VPI group and groups of each T stage (size only) were compared in the external (SEER) cohort. There were no significant survival differences between the T1-VPI and T2a groups (OS: P=0.706; LCSS: P=0.792) and T1-VPI and T2b groups, although the latter showed a trend toward lower P-values (OS: P=0.117; LCSS: P=0.094). In the internal cohort, a significant difference in OS was observed between patients with T1-VPI and those with T2b (P=0.049). Among patients with T1a tumors and VPI in the SEER database, the prognosis of the non-sub-lobectomy group was superior to that of the sub-lobectomy group, with intrathoracic recurrence as the predominant relapse pattern of T1 tumors with VPI (69.2%).

CONCLUSIONS

T1 tumors (<3 cm) with VPI can be staged as T2a in the 8th TNM staging system and surgical resection of T1a tumors is a concern when VPI is present.

Choice of the surgical approach for patients with stage I lung squamous cell carcinoma ≤3 cm

Background

We tried to explore the surgical procedures for stage I squamous cell carcinoma (SCC) with a size of ≤3 cm by using the Surveillance, Epidemiology, and End Results (SEER) database. Furthermore, we investigated the relationships between the chosen surgical option and the size of SCC.

Methods

In total, 1,147 patient data sets were collected from 2010 to 2011 using the SEER database. Afterwards, 849 patients with a pT1-2aN0M0 SCC with a size of ≤3 cm after a lobectomy or sublobectomy procedure were identified. Kaplan-Meier curves were conducted to compare the overall survival (OS) rates and the lung cancer-specific survival (LCSS) rates between the two surgical approaches. Cox proportional hazards regressions were performed to discover the independent risk factors for both the OS and LCSS rates. Lastly, subgroup analysis was stratified by the size of the SCC and then classified by the 8^th edition T category.

Results

The sublobectomy procedure did not demonstrate a difference for the OS rate. Additionally, it demonstrated a worse LCSS rate when compared with a lobectomy for stage I SCC. In the subgroup analysis, a lobectomy was shown to have a better survival outcome only when the SCC was >2 and ≤3 cm. Multivariable analysis showed that a size of >2 to ≤3 cm, and an age of >60 were independently associated with poorer OS while the sublobectomy procedure and pleural invasions (PI) were related with a poorer LCSS rate. In the stratification of data for the tumor size, the cox proportional analysis still confirmed the protective effects of the lobectomy in subgroups of SCCs with sizes between >2 to ≤3 cm as well as the T1c category.

Conclusions

The choice of the SCC surgery can be recommended based on the tumor size. A lobectomy procedure demonstrated a better LCSS against the sublobectomy in stage I SCC. SCC with sizes of >2 to ≤3 cm could become a pretty good indicator for lobectomy, while a sublobectomy may be an adequate substitute when the SCC size is ≤2 cm, especially for patients who cannot tolerate a lobectomy. T1c category can also suggest a lobectomy instead of sublobectomy for stage I SCC patients.

Survival with Parenchymal and Pleural Invasion of Non-Small Cell Lung Cancers Less than 30 mm

OBJECTIVE

To determine long-term survival of visceral pleural invasion (VPI) and parenchymal invasion (PAI) (angiolymphatic and/or vascular) on survival of NSCLCs less than 30 mm in maximum diameter.

METHODS

Kaplan-Meier survivals for NSCLCs, with and without VPI and/or PAI, were determined for a prospective cohort of screening participants stratified by pathologic tumor size (≤10 mm, 11-20 mm, and 21-30 mm) and nodule consistency. Log-rank test statistics were calculated.

RESULTS

The frequency of PAI versus VPI was significantly lower in patients with subsolid nodules than in those with solid nodules (4.9% versus 27.7% [p < 0.0001]), and correspondingly, Kaplan-Meier lung cancer survival was significantly higher among patients with subsolid nodules (99.1% versus 91.3% [p = 0.0009]). Multivariable Cox regression found that only tumor diameter (adjusted hazard ratio [HR] =1.07, 95% confidence interval [CI]: 1.01-1.14, p = 0.02) and PAI (adjusted HR = 3.15, 95% CI: 1.25-7.90, p = 0.01) remained significant, whereas VPI was not significant (p = 0.15). When clinical and computed tomography findings were included with the pathologic findings, Cox regression showed that the risk of dying of lung cancer increased 10-fold (HR = 10.06, 95% CI: 1.35-75.30) for NSCLCs in patients with solid nodules and more than twofold (by a factor of 2.27) in patients with moderate to severe emphysema (HR = 2.27, 95% CI: 1.01-5.11), as well as with increasing tumor diameter (HR = 1.06, 95% CI: 1.01-1.13), whereas PAI was no longer significant (p = 0.19).

CONCLUSIONS

Nodule consistency on computed tomography was a more significant prognostic indicator than either PAI or VPI. We propose that patients with NSCLC with VPI and a maximum tumor diameter of 30 mm or less not be upstaged to T2 without further large, multicenter studies of NSCLCs, stratified by the new T status and that classification be considered separately for patients with subsolid or solid nodules.

Prognostic impact of microscopic vessel invasion and visceral pleural invasion and their correlations with epithelial-mesenchymal transition, cancer stemness, and treatment failure in lung adenocarcinoma

OBJECTIVES

Microscopic vessel invasion (MVI) and visceral pleural invasion (VPI) have been recently reported as poor prognostic factors of non-small cell lung cancer. Epithelial-mesenchymal transition (EMT) and cancer stemness (CS) are known malignant phenotypes that induce resistance to cancer therapy. We aimed to assess the prognostic significance of MVI and the correlations among VPI/MVI, EMT, CS, and treatment failure for recurrent tumor.

MATERIALS AND METHODS

From 2002 to 2013, 1034 consecutive patients with pathological T1-4N0-2M0 lung adenocarcinoma underwent complete resection. Moreover, we established 206 tissue microarray (TMA) samples from 2002 to 2007. We then evaluated the prognostic impact of MVI, including conventional clinicopathological factors, and analyzed the VPI/MVI, EMT, CS, and treatment failure by TMA immunohistochemical staining.

RESULTS

Among the 1034 cases, the proportion of patients with a 5-year overall survival (OS) period was 63.9% and 88.2% (MVI: +/-; p < .001). Multivariate analysis revealed that both MVI and VPI were independent predictors of OS (HR 1.57 and 1.47, respectively). Significant separation of the OS rate curves was observed among the 3 groups [VPI/MVI: both positive (2), either positive (1), and both negative (0)]. Among the 206 TMA cases, these 3 groups of VPI/MVI were significantly correlated with EMT and CS. The median time to progression after recurrence were 3.8, 8.9, and 15.9 months, respectively (VPI/MVI: 2/1/0; p =  0.016).

CONCLUSION

MVI and VPI are significant prognostic factors of lung cancer, and they are correlated with EMT, CS, and treatment failure for recurrent tumor.

Prognostic value of tumor solid-part size and solid-part volume in patients with clinical stage I non-small cell lung cancer

Background

This study aimed to predict the malignant potential of clinical stage I non-small cell lung cancer (c-I NSCLC) by semiautomatic three-dimensional (3D) volumetric measurement of a tumor (3D-data) and the axial computed tomography (CT) data derived from a 3D volumetric dataset (2D-data). The predictive performance was evaluated in terms of overall survival (OS), disease-free survival (DFS), and pathological invasive factors (positive lymphatic invasion, blood vessel invasion, pleural invasion, or lymph node metastasis).

Methods

We identified 252 patients (122 male; mean age, 68 years; range, 23-84 years) with c-I NSCLC who underwent high resolution CT and reconstruction of 3D imaging, followed by complete resection between January 2012 and December 2015. In this study, 2D-data including whole tumor size (WTS) and solid-part size (SPS) and 3D-data including whole tumor volume (WTV) and solid-part volume (SPV) acquired by a 3D volume rendering software were analyzed.

Results

The area under the receiver operating characteristic (ROC) curve for WTS, SPS, WTV, SPV relevant to recurrence was 0.667, 0.727, 0.654, and 0.751 while analyses of ROC curves revealed optimal WTS, SPS, WTV, and SPV cut-off values to predict recurrence of 2.48 cm, 2.03 cm, 3,258 mm³ and 1,889 mm³, respectively. The association between SPS and SPV was the coefficient of determination (R ²) =0.59. Multivariate analysis showed that SPV >1,889 mm³ (P=0.016) and male (P=0.041) were significant predictors of OS whereas SPV >1,889 mm³ (P=0.001), male (P=0.003), and the serum carcinoembryonic antigen value (P=0.041) were significantly correlated with DFS. SPS, SPV as well as the combination of SPS and SPV were all significantly correlated with the prediction of OS and DFS, and the incidence of pathological invasive factors.

Conclusions

SPV and the integrated use of SPS and SPV was highly beneficial for the prediction of postoperative prognosis in c-I NSCLC.

Demographics, Safety and Quality, and Prognostic Information in Both the Seventh and Eighth Editions of the TNM Classification in 18,973 Surgical Cases of the Japanese Joint Committee of Lung Cancer Registry Database in 2010

INTRODUCTION

The Japanese Joint Committee of Lung Cancer Registry performed the fourth nationwide registry study of surgical cases. Demographics, safety and quality, prognostic information, and correlations between the seventh and the eighth editions of the TNM classification were investigated. The principal results were compared with those of previous Japanese Joint Committee of Lung Cancer Registry studies.

METHODS

The clinicopathologic profiles, staging, and prognosis of patients who had an operation for primary lung cancer in 2010 were retrospectively collected in 2016 and analyzed.

RESULTS

The cohort consisted of 18,973 patients from 297 hospitals (11,771 males, mean age 68.3 years). Tumor smaller than 2.0 cm was seen in 39.0% of patients, and limited resection was performed in 22.7%. The 30- and 90-day mortality rates were 0.43 and 1.26%, respectively. The overall and disease-free survival rates at 5 years were 74.7 and 67.8%, respectively. The respective 5-year survival rates by pathological stage in the seventh edition in the present study (2010) and in the previous study (2004) were 88.9% and 86.8% for stage IA, 76.7% and 73.9% for stage IB, 64.1% and 61.6% for stage IIA, 56.1% and 49.8% for stage IIB, 47.9% and 40.9% for stage IIIA, 30.2% and 27.8% for stage IIIB, and 36.1% and 27.9% for stage IV. The 5-year survival rates by clinical stage in the eighth edition in the present study were 97.0% for stage 0, 91.6% for stage IA1, 81.4% for stage IA2, 74.8% for stage IA3, 71.5% for stage IB, 60.2% for stage IIA, 58.1% for stage IIB, 50.6% for stage IIIA, 40.5% for stage IIIB, 37.5% for stage IIIC, and 36.0% for IVA/B. With restaging, the overall survival rates of clinical stage IA and IB in the seventh edition were stratified into stages 0 to IA3 and stages IA1 to IIA in the eighth edition, respectively.

CONCLUSIONS

This study demonstrates improved surgical results for lung cancer in Japan. The TNM revision for the eighth edition was supported by the assessment of stage migration from the previous edition and the prognostic stratification.

Dilemmas in Lung Cancer Staging

The advent of the 8th edition of the lung cancer staging system reflects a further meticulous evidence-based advance in the stratification of the survival of patients with lung cancer. Although addressing many limitations of earlier staging systems, several limitations in staging remain. This article reviews from a radiological perspective the limitations of the current staging system, highlighting the process of TNM restructuring, the residual issues with regards to the assignment of T, N, M descriptors, and their associated stage groupings and how these dilemmas impact guidance of multidisciplinary teams taking care of patients with lung cancer.