International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification predicts occult lymph node metastasis in clinically mediastinal node-negative lung adenocarcinoma

Accurate categorization and rapid pathological diagnosis correction with Micro-Raman technique in human lung adenocarcinoma infiltration level

Background

In the context of surgical interventions for lung adenocarcinoma (LADC), precise determination of the extent of LADC infiltration plays a pivotal role in shaping the surgeon's strategic approach to the procedure. The prevailing diagnostic standard involves the expeditious intraoperative pathological diagnosis of areas infiltrated by LADC. Nevertheless, current methodologies rely on the visual interpretation of tissue images by proficient pathologists, introducing an error margin of up to 15.6%.

Methods

In this study, we investigated the utilization of Micro-Raman technique on isolated specimens of human LADC with the objective of formulating and validating a workflow for the pathological diagnosis of LADC featuring diverse degrees of infiltration. Our strategy encompasses a thorough pathological characterization of LADC, spanning different tissue types and levels of infiltration. Through the integration of Raman spectroscopy with advanced deep learning models for simultaneous diagnosis, this approach offers a swift, precise, and clinically relevant means of analysis.

Results

The diagnostic performance of the convolutional neural network (CNN) model, coupled with the microscopic Raman technique, was found to be exceptional and consistent, surpassing the traditional support vector machine (SVM) model. The CNN model exhibited an area under the curve (AUC) value of 96.1% for effectively distinguishing normal tissue from LADC and an impressive 99.0% for discerning varying degrees of infiltration in LADCs. To comprehensively assess its clinical utility, Raman datasets from patients with intraoperative rapid pathologic diagnostic errors were utilized as test subjects and input into the established CNN model. The results underscored the substantial corrective capacity of the Micro-Raman technique, revealing a misdiagnosis correction rate exceeding 96% in all cases.

Conclusions

Ultimately, our discoveries highlight the Micro-Raman technique's potential to augment the intraoperative diagnostic precision of LADC with varying levels of infiltration. And compared to the traditional SVM model, the CNN model has better generalization ability in diagnosing different infiltration levels. This method furnishes surgeons with an objective groundwork for making well-informed decisions concerning subsequent surgical plans.

Transfer learning based approach for lung and colon cancer detection using local binary pattern features and explainable artificial intelligence (AI) techniques

Cancer, a life-threatening disorder caused by genetic abnormalities and metabolic irregularities, is a substantial health danger, with lung and colon cancer being major contributors to death. Histopathological identification is critical in directing effective treatment regimens for these cancers. The earlier these disorders are identified, the lesser the risk of death. The use of machine learning and deep learning approaches has the potential to speed up cancer diagnosis processes by allowing researchers to analyse large patient databases quickly and affordably. This study introduces the Inception-ResNetV2 model with strategically incorporated local binary patterns (LBP) features to improve diagnostic accuracy for lung and colon cancer identification. The model is trained on histopathological images, and the integration of deep learning and texture-based features has demonstrated its exceptional performance with 99.98% accuracy. Importantly, the study employs explainable artificial intelligence (AI) through SHapley Additive exPlanations (SHAP) to unravel the complex inner workings of deep learning models, providing transparency in decision-making processes. This study highlights the potential to revolutionize cancer diagnosis in an era of more accurate and reliable medical assessments.

The Society of Thoracic Surgeons Database Analysis: Comparing Sublobar Techniques in Stage IA Lung Cancer

BACKGROUND

This study compares sublobar resections-wedge resection and segmentectomy-in clinical stage IA lung cancers. It tests the hypothesis that overall survival after wedge resection is similar to segmentectomy.

METHODS

Adults undergoing wedge resection or segmentectomy for clinical stage IA lung cancer were identified from The Society of Thoracic Surgeons General Thoracic Surgery Database. Eligible patients were linked to the Centers for Medicare and Medicaid Services database using a matching algorithm. The primary outcome was long-term overall survival. Propensity scores overlap weighting (PSOW) adjustment of wedge resection using validated covariates was used for group difference mitigation. Kaplan-Meier and Cox regression models analyzed survival. All-cause first readmission, and morbidity and mortality were examined using PSOW regression models.

RESULTS

Of 9756 patients, 6141 met inclusion criteria, comprising 2154 segmentectomies and 3987 wedge resections. PSOW reduced differences between the groups. Unadjusted perioperative mortality was comparable, but wedge resection showed lower major morbidity rates. Weighted regression analysis indicated reduced mortality and major morbidity risks in wedge resection. Kaplan-Meier analysis revealed no mortality difference between groups, which was confirmed by PSOW Cox regression models. The cumulative risk of readmission was also comparable for both groups, with Cox Fine-Gray models showing no difference in rehospitalization risks.

CONCLUSIONS

In clinical stage IA lung cancer, relative to segmentectomy, wedge resection has comparable overall survival and lower perioperative morbidity, suggesting it is an equally effective option for the broader population of patients with clinical stage IA lung cancer, not only those at highest risk of complications.

Computed tomography imaging and clinical characteristics of pulmonary ground-glass nodules ≤2 cm with micropapillary pattern

BACKGROUND

The aim of this study was to investigate the imaging features, lymph node metastasis, and genetic mutations in micropapillary lung adenocarcinoma (imaging with mixed ground-glass nodules) ≤2 cm, to provide a more precise and refined basis for the selection of lung segment resection.

METHODS

A retrospective analysis of 162 patients with surgically resected pathologically confirmed cancers ≤2.0 cm in diameter (50 cases of micropapillary mixed ground-glass nodules [mGGNs], 50 cases of nonmicropapillary mGGNs, and 62 cases of micropapillary SNs [solid nodules]) was performed. mGGNs were classified into five categories according to imaging features. The distribution of these five morphologies in micropapillary with mGGN and nonmicropapillary with mGGN was analyzed. The postoperative pathology and prognosis of lymph node metastasis were also compared between micropapillary mGGNs and micropapillary with SNs. After searching the TCGA database, we demonstrated heterogeneity, high malignancy and high risk of microcapillary lung cancer cancers.

RESULTS

Different pathological subtypes of mGGN differed in morphological features (p < 0.05). The rate of lymph node metastasis was significantly higher in micropapillary mGGNs than in nonmicropapillary mGGNs. In the TCGA database samples, lactate transmembrane protein activity, collagen transcription score, and fibroblast EMT score were remarkably higher in micropapillary adenocarcinoma. Other pathological subtypes had a better survival prognosis and longer disease-free survival compared with micropapillary adenocarcinoma.

CONCLUSION

mGGNs ≤2 cm with a micropapillary pattern have a higher risk of lymph node metastasis compared with SNs, and computed tomography (CT) imaging features can assist in their diagnosis.

Preoperative 18F-FDG PET/CT and CT radiomics for identifying aggressive histopathological subtypes in early stage lung adenocarcinoma

Lung adenocarcinoma (ADC) is the most common non-small cell lung cancer. Surgical resection is the primary treatment for early-stage lung ADC while lung-sparing surgery is an alternative for non-aggressive cases. Identifying histopathologic subtypes before surgery helps determine the optimal surgical approach. Predominantly solid or micropapillary (MIP) subtypes are aggressive and associated with a higher likelihood of recurrence and metastasis and lower survival rates. This study aims to non-invasively identify these aggressive subtypes using preoperative 18F-FDG PET/CT and diagnostic CT radiomics analysis. We retrospectively studied 119 patients with stage I lung ADC and tumors ≤ 2 cm, where 23 had aggressive subtypes (18 solid and 5 MIPs). Out of 214 radiomic features from the PET/CT and CT scans and 14 clinical parameters, 78 significant features (3 CT and 75 PET features) were identified through univariate analysis and hierarchical clustering with minimized feature collinearity. A combination of Support Vector Machine classifier and Least Absolute Shrinkage and Selection Operator built predictive models. Ten iterations of 10-fold cross-validation (10 ×10-fold CV) evaluated the model. A pair of texture feature (PET GLCM Correlation) and shape feature (CT Sphericity) emerged as the best predictor. The radiomics model significantly outperformed the conventional predictor SUVmax (accuracy: 83.5% vs. 74.7%, p = 9e-9) and identified aggressive subtypes by evaluating FDG uptake in the tumor and tumor shape. It also demonstrated a high negative predictive value of 95.6% compared to SUVmax (88.2%, p = 2e-10). The proposed radiomics approach could reduce unnecessary extensive surgeries for non-aggressive subtype patients, improving surgical decision-making for early-stage lung ADC patients.

Lymph node metastasis and its risk factors in T1 lung adenocarcinoma

BACKGROUND

In this study, the focus was primarily on examining the occurrence of lymph node metastasis in T1 lung adenocarcinoma, while also analyzing the relationship between clinical variables such as imaging characteristics, pathological classifications, and lymph node metastasis.

METHODS

We retrospectively analyzed data from patients with T1 lung adenocarcinoma who underwent lobectomy and lymph node dissection between January 2016 and December 2019. Utilizing univariate and multivariate analyses, we assessed the associations between lymph node metastasis and various clinical factors, including imaging characteristics, lesion location and depth, and pathological subtypes.

RESULTS

Of the 433 patients with T1 lung adenocarcinoma, 139 had lymph node metastasis. Moreover, the incidence of node 1 (N1) lymph node, sequential, and node 2 (N2) skip metastases were 12.2%, 12.7%, and 7.2%, respectively. Univariate analysis revealed that tumor diameter, depth ratio, sex, invasive imaging features, and pathological subtype were significantly associated with lymph node metastasis. Multivariate analysis revealed that the tumor depth ratio, tumor diameter, pleural indentation or traction sign, nonvascular penetration sign, solid component, nonadherence, and micropapillary pathological subtype were risk factors for lymph node metastasis. In the multivariate analysis, the micropapillary pathological subtype was an independent risk factor for N2 skip metastasis.

CONCLUSIONS

In patients with clinical stage T1 lung adenocarcinoma, the risk of lymph node metastasis is higher for tumors located deep within the lung tissue with solid components, invasive preoperative imaging features, and larger diameters. For N2 skip lymph node metastasis, the micropapillary pathological subtype represents a significant high-risk factor.

The American Association for Thoracic Surgery (AATS) 2023 Expert Consensus Document: Staging and multidisciplinary management of patients with early-stage non-small cell lung cancer

Novel targeted therapy and immunotherapy drugs have recently been approved for use in patients with surgically resectable lung cancer. Accurate staging, early molecular testing, and knowledge of recent trials are critical to optimize oncologic outcomes in these patients.

Diagnostic efficacy of cryobiopsy for peripheral pulmonary lesions: A propensity score analysis

OBJECTIVES

Recently introduced cryobiopsy can provide quantitatively and qualitatively excellent specimens. However, few studies have directly compared the diagnostic yield of cryobiopsy for peripheral pulmonary lesions (PPLs) with that of conventional sampling methods.

MATERIAL AND METHODS

We retrospectively reviewed data from consecutive patients who underwent diagnostic bronchoscopy using radial endobronchial ultrasound and virtual bronchoscopic navigation for PPLs (October 2015 to September 2020). Patients who underwent cryobiopsy were assigned to the cryo group, whereas those who did not undergo cryobiopsy were assigned to the conventional group. The diagnostic outcomes of both groups were compared using propensity score analyses.

RESULTS

A total of 2,724 cases were identified, including 492 and 2,232 cases in the cryo and conventional groups, respectively. Propensity scoring was performed to match baseline characteristics, and 481 pairs of cases were selected for each matched group (m-group). The diagnostic yield was significantly higher in the m-cryo group than in the m-conventional group (89.2% vs. 77.6%, odds ratio [OR] = 2.36 [95% confidence interval [CI] = 1.65-3.38], P < 0.001). Propensity score stratification (OR = 2.35 [95% CI = 1.71-3.23]) and regression adjustment (OR = 2.54 [95% CI = 1.83-3.52]) also demonstrated the diagnostic advantages of cryobiopsy. The subgroup analysis revealed that cryobiopsy was notably effective for lesions in the middle lobe/lingula, right/left lower lobe, lesions with ground-glass opacity, and lesions invisible on chest radiography. Although there were more cases of grade 2 and 3 bleeding in the m-cryo group than in the m-conventional group (38.0% vs. 10.2% and 1.5% vs. 0.8%, respectively; P < 0.001), no grade 4 bleeding was observed.

CONCLUSION

The propensity score analyses revealed that cryobiopsy was associated with a higher diagnostic yield for PPLs than conventional sampling methods. However, increased bleeding risk should be noted as a potential complication.

The IASLC Proposed Grading System Accurately Predicts Prognosis and Mediastinal Nodal Metastasis in Patients With Clinical Stage I Lung Adenocarcinoma

The International Association for the Study of Lung Cancer (IASLC) recently proposed a new grading system for lung adenocarcinoma (LUAD). We aimed to validate the prognostic performance of the grading system and explore its role in guiding the strategy of lymph node (LN) dissection. We retrospectively reviewed 1029 patients with clinical stage I LUAD who underwent surgery between 2011 and 2013. The association between mediastinal nodal metastasis and grading system was evaluated. To investigate the value of the grading system in guiding LN dissection strategies, 3 pathologists evaluated the feasibility of identifying the grading system using frozen section (FS). The differences in prognosis between all neighboring grades were highly significant based on the grading system ( P <0.001). Notably, almost no grade 1 LUAD (1.4%) had pN2 disease, whereas higher rates were found in grade 2 LUAD (9.6%) and grade 3 LUAD (18.3%) ( P <0.001). Multivariate logistic regression analysis revealed that higher tumor grade was an independent predictor of mediastinal nodal metastasis ( P =0.002). Moreover, limited mediastinal LN dissection had equivalent prognosis in grade 1 LUAD, but significantly worse prognosis in grade 2 and grade 3 LUAD than systematic mediastinal LN dissection. The overall accuracy of using intraoperative FS to identify the IASLC grading system was 85.4% (κ=0.765) with substantial agreement. The IASLC grading system could accurately stratify prognosis and predict mediastinal nodal metastasis in patients with clinical stage I LUAD. FS was feasible for identifying the IASLC grading system.

Prognosis of the second predominant subtype in lung adenocarcinoma: a retrospective single-center cohort study

Background

The histologic classification of lung adenocarcinoma (LUAD) was mainly divided into three pathological subtype groups: the low-grade predominant subtype group (lepidic), the intermediate-grade predominant subtype group (papillary and acinar), and the high-grade predominant subtype group (micropapillary and solid). Previous studies have focused on the prognostic impact of predominant subtypes of lung adenocarcinoma. In this investigation, we investigated the effect of the second predominant subtype on prognosis.

Methods

The data of LUAD postoperative patients were retrospectively collected. Exclusion criteria included cases in which the pathologic results revealed a single characteristic, the presence of invasive mucinous LUAD, or if the first predominant and the second predominant groups could not be distinguished. Categorical variables were compared with the two-tailed Pearson χ² test and continuous variables with the Student's t-test. Follow-up was conducted by telephone and other methods. Independent prognostic factors of the second major subtype were determined by the Kaplan-Meier method and log-rank test. The Cox proportional risk regression model was used to analyze the possible prognostic factors.

Results

Among 293 patients, the mean age was 61.9 years and 47.1% were male. The results revealed that when the predominant group was the low-grade group, the second predominant groups had no significant influence on overall survival (OS) (P=0.15) but significantly influenced disease free survival (DFS) (P=0.037). Subsequently, when the predominant group was the intermediate-grade group, the second predominant groups significantly influenced OS (P=0.024) but had no significant influence on DFS (P=0.3). Moreover, when the predominant group was the high-grade group, the second predominant groups significantly influenced OS (P=0.033) but had no significant influence on DFS (P=0.31).

Conclusions

The independent prognostic effect of the second predominant group was not identified for OS and DFS of lung adenocarcinoma. The effects of the second predominant subtype groups on OS and DFS were not evenly distributed among different predominant subtype groups, and the low-grade second predominant subtype exhibited some protective effects on the middle-grade predominant subtypes.

Computed tomography radiomics-based distinction of invasive adenocarcinoma from minimally invasive adenocarcinoma manifesting as pure ground-glass nodules with bubble-like signs

BACKGROUND

To explore an effective model based on radiomics features extracted from nonenhanced computed tomography (CT) images to distinguish invasive adenocarcinoma (IAC) from minimally invasive adenocarcinoma (MIA) presenting as pure ground-glass nodules (pGGNs) with bubble-like (B-pGGNs) signs.

PATIENTS AND METHODS

We retrospectively reviewed 511 nodules (MIA, n = 288; IAC, n = 223) between November 2012 and June 2018 from almost all pGGNs pathologically confirmed MIA or IAC. Eventually, a total of 109 B-pGGNs (MIA, n = 55; IAC, n = 54) from 109 patients fulfilling the criteria were randomly assigned to the training and test cluster at a ratio of 7:3. The gradient boosting decision tree (GBDT) method and logistic regression (LR) analysis were applied to feature selection (radiomics, semantic, and conventional CT features). LR was performed to construct three models (the conventional, radiomics and combined model). The performance of the predictive models was evaluated using the area under the curve (AUC).

RESULTS

The radiomics model had good AUCs of 0.947 in the training cluster and of 0.945 in the test cluster. The combined model produced an AUC of 0.953 in the training cluster and of 0.945 in the test cluster. The combined model yielded no performance improvement (vs. the radiomics model). The rad_score was the only independent predictor of invasiveness.

CONCLUSION

The radiomics model showed excellent predictive performance in discriminating IAC from MIA presenting as B-pGGNs and may provide a necessary reference for extending clinical practice.

Which will carry more weight when CTR > 0.5, solid component size, CTR, tumor size or SUVmax?

BACKGROUND

This study was conducted to explore the clinical significance of the maximum standard uptake value (SUVmax) in the clinical stage IA lung adenocarcinoma with tumor size ≤ 2 cm and consolidation to tumor ratio (CTR) > 0.5.

METHODS

We retrospectively reviewed non-small cell lung cancer patients who underwent surgeries between January 2014 and March 2017. Clinical stage IA lung adenocarcinoma patients with tumor of size ≤ 2 cm and CTR > 0.5 were enrolled. The patients were divided into two groups: part-solid and pure-solid based on whether CTR = 1.0 or not. Nodules with any amount of solid or micropapillary components were regarded as the high-risk subtype. Time-dependent ROC curve was used to determine the best cut-off value. Finally, we analyzed the relationship between SUVmax, high-risk subtypes, node metastasis and 5-year relapse-free survival and overall survival.

RESULTS

Totally, 270 patients were included. The distribution of pathological subtypes (p < 0.001), SUVmax (p < 0.001), and pathological N stage (p < 0.001) were different between the two groups. Multivariable analysis indicated that SUVmax could predict high-risk subtypes in cases of part-solid nodules (p < 0.001) and both high-risk subtypes (p = 0.022) and node metastasis (p < 0.001) in cases of pure-solid ones. SUVmax ≥ 2.6 and SUVmax ≥ 5.1 were strongly associated with 5-year relapse-free survival (p < 0.001) and 5-year overall survival (p < 0.001) among all the patients, respectively.

CONCLUSION

Part-solid nodules with 0.5 < CTR < 1 and pure-solid nodules in lung adenocarcinoma show different clinicopathological characteristics, especially in SUVmax. SUVmax is significantly associated with high-risk subtypes, node metastasis, 5-year relapse-free survival and overall survival.

Cryobiopsy as a reliable technique for the preoperative identification of micropapillary/solid components in early-stage lung adenocarcinoma

OBJECTIVES

Micropapillary (MIP) and solid (SOL) subtypes of early-stage lung adenocarcinomas are associated with lymph node metastasis and local recurrence after limited resection. Preoperative identification of these components may influence the decisions of treatment strategy, additional lymph node evaluation, indication for limited resection, and extent of lymph node dissection. However, conventional biopsy specimens are insufficient for identifying these subtypes, especially MIP components. Cryobiopsy can collect larger tissue samples with fewer crush artifacts than conventional forceps biopsy, which would be helpful for detecting MIP/SOL components. Thus, this study aimed to analyze the feasibility of using cryobiopsy for MIP/SOL subtype detection.

MATERIAL AND METHODS

Consecutive patients who underwent surgery for clinical IA lung cancer following a preoperative diagnosis of adenocarcinoma by cryobiopsy at our institution between October 2017 and July 2019 were retrospectively examined. The concordance rate of MIP/SOL subtypes between the specimens obtained by cryobiopsy and surgery was investigated.

RESULTS

In total, 115 patients were evaluated. There were 26 (22.6%) and 14 (12.2%) patients with MIP and SOL subtypes, respectively. For concordance of MIP/SOL subtypes, the sensitivity was 65.7% (95% confidence interval [CI]: 57.7-65.7%). For the primary or secondary predominant patterns, a more satisfactory concordance rate of 72.2% (95% CI: 52.6-86.2%) was obtained. On assessing each subtype, high sensitivity was noted in SOL-predominant patterns (85.7%, 95% CI: 56.5%-96.0%) and MIP-secondary predominant patterns (83.3%, 95% CI: 45.8-97.0%). However, SOL-secondary predominant patterns revealed low sensitivity (0%, 95% CI, 0-38.2%). Overall, the MIP subtypes had higher sensitivity than the SOL subtypes (65.4% vs. 50.0%).

CONCLUSION

Cryobiopsy could be reliable for identifying MIP/SOL components, especially the MIP component, in clinical stage IA adenocarcinomas.

3D gray density coding feature for benign-malignant pulmonary nodule classification on chest CT

PURPOSE

Early detection is significant to reduce lung cancer-related death. Computer-aided detection system (CADs) can help radiologists to make an early diagnosis. In this paper, we propose a novel 3D gray density coding feature (3D GDC) and fuse it with extracted geometric features. The fusion feature and random forest are used for benign-malignant pulmonary nodule classification on Chest CT.

METHODS

First, a dictionary model is created to acquire codebook. It is used to obtain feature descriptors and includes 3D block database (BD) and distance matrix clustering centers. 3D BD is balanced and randomly selecting from benign and malignant pulmonary nodules of training data. Clustering centers is got by clustering the distance matrix, which is the distance between every two blocks in 3D BD. Then, feature descriptor is obtained by coding the pulmonary nodule with codebook, and 3D GDC feature is the result of histogram statistics on feature descriptor. Second, geometric features are extracted for fusion feature. Finally, random forest is performed for benign-malignant pulmonary nodule classification with fusion feature of the 3D gray density coding feature and the geometric features.

RESULTS

We verify the effectiveness of our method on the public LIDC-IDRI dataset and the private ZSHD dataset. For LIDC-IDRI dataset, compared with other state-of-the-art methods, we achieve more satisfactory results with 93.17 ± 1.94% for accuracy and 97.53 ± 1.62% for AUC. As for private ZSHD dataset, it contains a total of 238 lung nodules from 203 patients. The accuracy and AUC achieved by our method are 90.0% and 93.15%.

CONCLUSIONS

The results show that our method can provide doctors with more accurate results of benign-malignant pulmonary nodule classification for auxiliary diagnosis, and our method is more interpretable than 3D CNN methods, which can provide doctors with more auxiliary information.

What Should Thoracic Surgeons Consider during Surgery for Ground-Glass Nodules?: Lymph Node Dissection

Thoracic surgeons need to be aware of several important points regarding intraoperative lymph node dissection during surgery for non-small cell lung cancer with ground-glass opacities. The first point relates to the need for lymph node dissection during sublobar resection. Since even patients undergoing sublobar resection may benefit from lymph node dissection, it should be selectively performed according to adequate indications, which require further study. Second, there seems to be no difference in postoperative morbidity between systematic sampling and systematic dissection, but the survival benefit from systematic dissection remains unclear. The results of randomized controlled trials on this topic are conflicting, and their evidence is jeopardized by a high risk of bias in terms of the study design. Therefore, further randomized controlled trials with a sound design should investigate this issue. Third, more favorable survival outcomes tend to be positively associated with the number of examined lymph nodes. Minimum requirements for the number of examined lymph nodes in non-small cell lung cancer should be defined in the future. Finally, lobe-specific lymph node dissection does not have a negative prognostic impact. It should not be routinely performed, but it can be recommended in selected patients with smaller, less invasive tumors. Results from an ongoing randomized controlled trial on this topic should be awaited.

The Immune Heterogeneity Between Pulmonary Adenocarcinoma and Squamous Cell Carcinoma: A Comprehensive Analysis Based on lncRNA Model

Adenocarcinoma (AD) and squamous cell carcinoma (SCC) are both classified as major forms of non-small cell lung cancer, but differences in clinical prognoses and molecular mechanisms are remarkable. Recent studies have supported the importance of understanding immune status in that it influences clinical outcomes of cancer, and immunotherapies based on the theory of “immune editing” have had notable clinical success. Our study aimed to identify specific long non-coding (lnc) RNAs that control key immune-related genes and to use them to construct risk models for AD and SCC. Risk scores were used to separate patients into high- and low-risk groups, and we validated the prognostic significance of both risk scores with our own cohorts. A Gene Set Enrichment Analysis suggested that the immune responses of patients in the AD high-risk group and the SCC low-risk group tended to be weakened. Evaluation of immune infiltration revealed that the degree of infiltration of dendritic cells is of particular importance in AD. In addition, prediction of responses to immune checkpoint inhibitor (ICI) treatments, based on the T Cell Immune Dysfunction and Exclusion and immunophenoscore models, indicated that deterioration of the immune microenvironment is due mainly to T cell exclusion in AD patients and T cell dysfunction in SCC patients and that high-risk patients with SCC might benefit from ICI treatment. The prediction of downstream targets via The Cancer Proteome Atlas and RNA-seq analyses of a transfected lung cancer cell line indicated that the lncRNA LINC00996 is a potential therapeutic target in AD.

Preoperative clinical and tumor genomic features associated with pathologic lymph node metastasis in clinical stage I and II lung adenocarcinoma

While next-generation sequencing (NGS) is used to guide therapy in patients with metastatic lung adenocarcinoma (LUAD), use of NGS to determine pathologic LN metastasis prior to surgery has not been assessed. To bridge this knowledge gap, we performed NGS using MSK-IMPACT in 426 treatment-naive patients with clinical N2-negative LUAD. A multivariable logistic regression model that considered preoperative clinical and genomic variables was constructed. Most patients had cN0 disease (85%) with pN0, pN1, and pN2 rates of 80%, 11%, and 9%, respectively. Genes altered at higher rates in pN-positive than in pN-negative tumors were STK11 (p = 0.024), SMARCA4 (p = 0.006), and SMAD4 (p = 0.011). Fraction of genome altered (p = 0.037), copy number amplifications (p = 0.001), and whole-genome doubling (p = 0.028) were higher in pN-positive tumors. Multivariable analysis revealed solid tumor morphology, tumor SUVmax, clinical stage, SMARCA4 and SMAD4 alterations were independently associated with pathologic LN metastasis. Incorporation of clinical and tumor genomic features can identify patients at risk of pathologic LN metastasis; this may guide therapy decisions before surgical resection.

Complex sleeve lobectomy has the same surgical outcome when compared with conventional lobectomy in patients with lung cancer

OBJECTIVES

No significant data are available to assess whether complex sleeve lobectomy (complex-SL) can be considered comparable to conventional lobectomy (CL) in terms of surgical outcome. The purpose of this study was to compare surgical and oncological outcomes of complex-SL with CL in patients with lung cancer.

METHODS

Between 2000 and 2015, a total of 568 patients who underwent open CL (defined as resection of only 1 lobe) and 187 patients who underwent SL were analysed. The SL group was divided into 2 subgroups: standard-SL (bronchial SL, n = 106) and complex-SL (n = 81) (defined as bronchial sleeve resection together with another surgical intervention: bronchovascular SL, n = 40; vascular SL, n = 26; atypical bronchoplasty with resection of more than 1 lobe, n = 12; bronchial SL + chest wall resection, n = 3).

RESULTS

The complex-SL group had more patients with chronic obstructive pulmonary disease (COPD) (25.9% vs 12.5%, P = 0.001), neoadjuvant treatment (39.5% vs 12.0%, P < 0.001), advanced-stage non-small-cell lung cancer (53.2% vs 33.1%, P = 0.001) and low preoperative forced expiratory volume in 1 s (77.2% vs 84.3%, P = 0.004) than the CL group. The overall surgical mortality (in-hospital or 30-day) was 2.6% (n = 20); it was 2.8% for CL and 2.8% for complex-SL. Postoperative complications occurred in 34.9% of the CL group and 39.5% of the complex-SL group (P = 0.413). The pulmonary complication rate was similar between the groups (24.1% for CL, 27.2% for complex-SL, P = 0.552). The 5-year survival in the CL group was 57.1%, and in the complex-SL group it was 56.2% (P = 0.888). Multivariate analysis showed that TNM stage (P < 0.001) and N status (P < 0.001) were significant and independent negative prognostic factors for survival.

CONCLUSIONS

Complex-SL had a comparable outcome to CL, although the complex-SL group had more patients with advanced-stage NSCLC, low preoperative forced expiratory volume in 1 s and COPD.

The Prognostic Value of Non-Predominant Micropapillary Pattern in a Large Cohort of Resected Invasive Lung Adenocarcinoma Measuring ≤3 cm

The aim of this study was to analyze the influence of non-predominant micropapillary pattern in small sized invasive lung adenocarcinoma. A total of 986 lung adenocarcinoma patients with tumor size ≤3 cm were identified and classified according to the IALSC/ATS/ERS classification. Emphasis was placed on the impact of non-predominant micropapillary pattern on disease-free survival (DFS) and overall survival (OS). The relationship between lung adenocarcinoma subtype and lymph node involvement, EGFR mutation and KRAS mutation was also evaluated. A nomogram was developed to predict the probability of 3- and 5-year OS for these patients. The concordance index and calibration plot were used to validate this model. Among all 986 patients, the percentages of lymph node involvement were: 58.1, 50.0, 33.5, 21.4, 21.1, 10.9, 0, and 0% for micropapillary predominant, solid predominant, acinar predominant, papillary predominant, invasive mucinous adenocarcinoma (IMA), lepidic predominant, minimally invasive adenocarcinoma (MIA), adenocarcinoma in situ (AIS), respectively. The frequency of EGFR mutation in the cases of lepidic predominant, acinar predominant, MIA, micropapillary predominant, papillary predominant, solid predominant, IMA, and AIS were 51.1, 45.2, 44.4, 36.8, 29.3, 26.8, 8.3, and 0%, respectively. A non-predominant micropapillary pattern was observed in 344 (38.4%) invasive adenocarcinoma (IAC), and its presence predicted a poorer DFS (median: 56.0 months vs. 66.0 months, P <0.001) and OS (median: 61.0 months vs. 70.0 months, P <0.001). After propensity score matching, non-predominant micropapillary pattern retained its unfavorable effect on DFS (P = 0.007) and OS (P = 0.001). Multivariate analysis showed that non-predominant micropapillary pattern was identified as an independent prognostic factor for DFS (P = 0.003) and OS (P <0.001) in IAC. The nomogram showed good calibration and reliable discrimination ability (C-index = 0.775) to evaluated the 3- and 5-year OS. This retrospective analysis of patients with small sized IAC suggests the value of non-predominant micropapillary pattern to predict poor prognosis. A reliable nomogram model was constructed to provide personalized survival predictions.

Application of Artificial Neural Network to Preoperative 18F-FDG PET/CT for Predicting Pathological Nodal Involvement in Non-small-cell Lung Cancer Patients

Purpose: To evaluate the performance of artificial neural networks (aNN) applied to preoperative ¹⁸F-FDG PET/CT for predicting nodal involvement in non-small-cell lung cancer (NSCLC) patients.

Methods: We retrospectively analyzed data from 540 clinically resectable NSCLC patients (333 M; 67.4 ± 9 years) undergone preoperative ¹⁸F-FDG PET/CT and pulmonary resection with hilo-mediastinal lymphadenectomy. A 3-layers NN model was applied (dataset randomly splitted into 2/3 training and 1/3 testing). Using histopathological reference standard, NN performance for nodal involvement (N0/N+ patient) was calculated by ROC analysis in terms of: area under the curve (AUC), accuracy (ACC), sensitivity (SE), specificity (SP), positive and negative predictive values (PPV, NPV). Diagnostic performance of PET visual analysis (N+ patient: at least one node with uptake ≥ mediastinal blood-pool) and of logistic regression (LR) was evaluated.

Results: Histology proved 108/540 (20%) nodal-metastatic patients. Among all collected data, relevant features selected as input parameters were: patients' age, tumor parameters (size, PET visual and semiquantitative features, histotype, grading), PET visual nodal result (patient-based, as N0/N+ and N0/N1/N2). Training and testing NN performance (AUC = 0.849, 0.769): ACC = 80 and 77%; SE = 72 and 58%; SP = 81 and 81%; PPV = 50 and 44%; NPV = 92 and 89%, respectively. Visual PET performance: ACC = 82%, SE = 32%, SP = 94%; PPV = 57%, NPV = 85%. Training and testing LR performance (AUC = 0.795, 0.763): ACC = 75 and 77%; SE = 68 and 55%; SP = 77 and 82%; PPV = 43 and 43%; NPV = 90 and 88%, respectively.

Conclusions: aNN application to preoperative ¹⁸F-FDG PET/CT provides overall good performance for predicting nodal involvement in NSCLC patients candidate to surgery, especially for ruling out nodal metastases, being NPV the best diagnostic result; a high NPV was also reached by PET qualitative assessment. Moreover, in such population with low a priori nodal involvement probability, aNN better identify the relatively few and unexpected nodal-metastatic patients than PET analysis, so supporting the additional aNN use in case of PET-negative images.

Targeted Sequencing Analysis of Predominant Histological Subtypes in Resected Stage I Invasive Lung Adenocarcinoma

Objective: Lung adenocarcinoma (LADC) is classified into five main histological subtypes with distinct clinicopathologic characteristics: lepidic-predominant adenocarcinoma (LPA), acinar-predominant adenocarcinoma (APA), papillary-predominant adenocarcinoma (PPA), micropapillary-predominant adenocarcinoma (MPA) and solid-predominant adenocarcinoma (SPA). However, the mutational profiles of predominant histological subtypes have not been well defined. In this study, we aimed to reveal the genomic landscape of 5 main histological subtypes. Patients and Methods: We performed next-generation sequencing (NGS) in a cohort of 86 stage I invasive adenocarcinoma (IAC) patients, using a customized panel including 168 cancer-associated genes. Results: Our analysis identified a total of 302 genomic alterations. Five subtypes showed different mutation profiles with LPA, APA, PPA, MPA and SPA had an average mutation rate of 1.95 (range: 0-5), 2.56 (range: 1-6), 3.5 (range: 1-7), 3.75 (range: 1-8) and 6.05 (range: 2-12), respectively (p=4.17e-06). Driver mutations occurred in 96.55% (83/86) of all patients. EGFR (73.3%), KRAS (9.3%), ALK (4.7%) and MET (4.7%) are the most commonly mutated lung cancer driver genes, TP53 is the top mutated tumor suppressor gene. SPA patients harbored more driver mutations and higher frequency of TP53 than LPA patients. Interestingly, LRP1B mutations, which has been reported to be associated with high tumor mutation burden and better response to immunotherapy, were only detected from 5 SPA patients (p=0.001). No patients from other four cohorts harbored LRP1B mutations. Conclusions: We revealed distinctive mutation landscape of the 5 major histological subtypes of LADC, evident by distinctive average mutation rate with SPA and LPA having the highest and lowest average mutation rate, respectively. SPA patients showed higher mutation rate of LRP1B and higher rates for PD-L1 positivity, indicating that SPA patients may have better response to immunotherapy.

Validation of the 8th Edition Nodal Staging and Proposal of New Nodal Categories for Future Editions of the TNM Classification of Non-Small Cell Lung Cancer

BACKGROUND

The International Association for the Study of Lung Cancer (IASLC) N classifications, which depend on the location and involvement of the lymph nodes, provide accurate prognoses. This study validated the efficiency of classifications using a single-institution dataset and proposed a modified system based on 5-level N1 node dissection.

METHODS

From January 2005 to December 2014, 1851 patients with completely resected non-small cell lung cancer were reviewed. According to the IASLC recommendations, N1 is further subdivided into N1a (single) and N1b (multiple), N2 is divided into N2a1 (single station without N1), N2a2 (single station with N1), and N2b (multiple station). Additionally, we evaluated dividing N0 into N0a (with level 13/14 examination) and N0b (without level 13/14 examination), and N1 into N1a* (only level 13/14 positive) and N1b* (level 10-12 positive). Overall survival was also compared.

RESULTS

Multivariate analysis showed that the N classifications recommended by the IASLC and those proposed and evaluated by this study could both significantly predict the prognoses of patients (p < 0.001, respectively). There was no significant difference in survival between N1b and N1a (hazard ratio [HR] 1.049, p = 0.83) and N2a1 and N1b (HR 1.314, p = 0.261); however, there were significant differences between N0a and N0b (HR 1.778, p < 0.001) and N1a* and N1b* (HR 2.014, p = 0.019). The survival curve of N1a* overlapped N0b (HR 0.997, p = 0.991), and N2a1 overlapped N1b* (HR 0.842, p = 0.444).

CONCLUSION

More detailed nodal information is required to facilitate future revisions of N staging.

Clinical implication of minimal presence of solid or micropapillary subtype in early-stage lung adenocarcinoma

BACKGROUND

We investigated the clinical features and surgical outcomes of lung adenocarcinoma with minimal solid or micropapillary (S/MP) components, with a focus on stage IA.

METHODS

We enrolled 506 patients with lung adenocarcinoma who underwent curative resection in this study. Clinical features and surgical outcomes were compared between the groups with and without the S/MP subtype (S/MP+ and S/MP-, respectively), and between the group with an S/MP proportion of ≤5% (S/MP5) and the S/MP-.

RESULTS

The S/MP subtype was present in 247 patients (48.8%); 129 (25.5%) were grouped as the S/MP5 group. The S/MP+ and S/MP5 groups had larger tumors, higher frequency of lymph node metastasis, and more advanced stages of disease than the S/MP- group (P < 0.001, all comparisons). Pleural, lymphatic, and vascular invasions occurred more frequently in the S/MP+ and S/MP5 groups (P < 0.001, all comparisons for S/MP+ vs. S/MP-; P ≤ 0.01, all comparisons for S/MP5 vs. S/MP-). The S/MP+ and S/MP5 groups showed a shorter time to recurrence and cancer-related death than the S/MP- group(P < 0.001, both comparisons). For stage I, the presence or absence of the S/MP subtype defined prognostic subgroups better than the stage IA/IB classification. Notably, in the multivariate analysis, the minimal S/MP component was a significant predictor of recurrence, even in stage IA.

CONCLUSIONS

The presence of the minimal S/MP component was a significant predictor of poor prognosis after surgery, even in stage IA patients. Clinical trials to evaluate the advantages of adjuvant chemotherapy for this subset of patients and further investigations to understand underlying biological mechanisms of poor prognosis are needed.

KEY POINTS

Significant findings of the study: We demonstrated that only minimal presence of solid or micropapillary component was profoundly associated with aggressive clinicopathological features and poor prognosis after complete resection even in stage IA lung adenocarcinoma.

WHAT THIS STUDY ADDS

Our results suggest that minimal presence of these subtypes is a strong prognostic factor which should be taken into account in the risk assessment for adjuvant chemotherapy in lung adenocarcinoma.

The Diagnostic and Prognostic Roles of Combined Expression of Novel Biomarkers in Lung Adenocarcinoma and Lung Squamous Cell Carcinoma: An Immunohistochemical Study

Background & Objective:

Diagnosis and discrimination of lung adenocarcinoma (LUAD) from lung squamous cell carcinoma (LUSC) is critical to select the appropriate treatment regimen as recently targeted therapies require accurate subtyping of nonsmall-cell lung carcinoma (NSCLCs). There are currently several biomarkers that could be used for differentiation between LUAD and LUSC, but they have less sensitivity, specificity, and clinical applicability. The aim of this study was to assess the diagnostic and prognostic values of CLCA2, SPATS2, ST6GALNAC1, and Adipophilin tissue expression in the tissues retrieved from LUAD and LUSC patients using immunohistochemistry.

Methods:

The current study was performed on the samples retrieved from sixty primary lung masses that were diagnosed as LUAD and LUSC. Immunohistochemistry was performed by using a panel of CLCA2, SPATS2, and ST6GALNAC1. We assessed the diagnostic roles of the studied markers in the discrimination between LUAD and LUSC and their prognostic values.

Results:

SPATS2 and CLCA2 were expressed higher in LUSC than LUAD. ST6GALNAC1 and Adipophilin showed higher expression in LUAD than LUSC (P<0.001). The sensitivity and specificity of CLCA2, SPATS2, ST6GALNAC1 and Adipophilin in adequate subtyping and reaching the accurate diagnosis was 100%. We found only significant difference in survival rate between the patients with negative and positive CLCA2 expression (P=0.038 and P=0.019, respectively).

Conclusion:

The combination of biomarkers of CLCA2, SPATS2, ST6GALNAC1, and Adipophilin may lead to an appropriate subtyping of lung cancer and reaching accurate diagnosis with the highest sensitivity and specificity.

Impact of histological components on selecting limited lymphadenectomy for lung adenocarcinoma ≤ 2 cm

OBJECTIVES

There is still some dispute regarding the performance of limited mediastinal lymphadenectomy (LML) even for lung adenocarcinoma ≤ 2 cm. We aimed to recognize the potential candidates who can benefit from LML based on the percentage of histological components (PHC).

METHODS

We analyzed 1160 surgical patients with invasive lung adenocarcinoma ≤ 2 cm from seven institutions between January 2012 and December 2015. All histological subtypes were listed in 5% increments by pathological slices. To test the accuracy of frozen section in judging PHC, frozen section slides from 140 cases were reviewed by three pathologists.

RESULTS

There were 882 patients with systematic mediastinal lymphadenectomy (SML) and 278 with LML. Multivariable analysis indicated that, the total percentage of micropapillary and solid components (PHC_MIP+S) > 5 % was the independent predictor of N2 metastasis (P < 0.001). Overall, recurrence-free survival (RFS) and overall survival (OS) favored SML compared with LML, but the subgroup analysis revealed LML and SML had similar prognosis in the group of PHC_MIP+S ≤ 5 %. Moreover, multivariable Cox analysis showed LML (vs. SML) was independently associated with worse prognosis for patients with PHC_MIP+S > 5 % (RFS, HR = 2.143, P < 0.001; OS, HR=1.963, P < 0.001), but not for those with PHC_MIP+S ≤ 5 % (RFS, P = 0.398; OS, P = 0.298). The sensitivity and specificity of frozen section to intraoperatively identify PHC_MIP+S ≤ 5 % were 97.6 % and 84.2 %, respectively.

CONCLUSIONS

PHC_MIP+S showed the predictive value for N2 metastasis and procedure-specific outcome (LML vs. SML). It may serve as a feasible indicator for identifying proper candidates of LML by using intraoperative frozen section.

Both the presence of a micropapillary component and the micropapillary predominant subtype predict poor prognosis after lung adenocarcinoma resection: a meta-analysis

Objective

It has been confirmed that the micropapillary (MP) pattern is a poor prognostic factor after resection of lung adenocarcinoma (ADC), but the proportion of the MP component as a prognostic criterion is still controversial. Hence, a meta-analysis was performed to evaluate whether the presence of an MP component has equal prognostic power as the MP predominant subtype.

Methods

Literature retrieval was performed in the MEDLINE, EMBASE, and Cochrane databases until December 23, 2019. Eligible studies were selected based on the inclusion and exclusion criteria. The included studies were divided into two subgroups, the MP component subgroup and the MP predominant subgroup, according to the proportion of the MP pattern to analyse the effect of this pattern on disease-free survival (DFS) and overall survival (OS). The hazard ratio (HR) and 95% confidence interval (CI) were extracted from each study. Review Manager 5.3 was used for statistical analyses.

Results

Finally, 10 studies, including a total of 4934 lung ADC patients, were included in this meta-analysis. Our results indicated a significantly worse pooled DFS (HR 1.62, 95% CI 1.20–2.21) and OS (HR 1.53, 95% CI 1.19–1.96) in the subgroup of MP predominant subtype patients. The pooled DFS (HR 1.80, 95% CI 1.45–2.85) and OS (HR 2.26, 95% CI 1.46–3.52) were also poor in the subgroup of patients with the presence of an MP component.

Conclusions

Both the presence of an MP component and the MP predominant subtype are related to poor DFS and OS after lung ADC resection and represent adverse prognostic factor for lung ADC patients. However, there are some limitations in this meta-analysis, and quantitative stratification based on the proportion of the MP component is needed to explore its effect on prognosis of lung ADC patients in the future.

Discriminating between bronchiolar adenoma, adenocarcinoma in situ and minimally invasive adenocarcinoma of the lung with CT

PURPOSE

To identify computed tomography (CT) features that may help distinguish bronchiolar adenoma (BA) from lung adenocarcinomas in situ (AIS) and minimally invasive adenocarcinomas (MIA) among lung lesions presenting as ground-glass nodules (GGNs).

MATERIALS AND METHODS

A total of 140 patients with GGNs confirmed by surgery and pathology, were reviewed retrospectively. There were 68 men and 72 women with a mean age of 64.3±8.9 (SD) years (range: 31 - 85 years). The CT features of BA, AIS, and MIA were analyzed and compared. CT features, including percentage of solid component, maximum diameter of solid component, lesion density, location, margin, shape, pseudo-cavitation, calcification, ill-defined peripheral opacity, and air bronchogram, were analyzed using multivariate logistic regression and receiver operating characteristic curves.

RESULTS

There were 11/140 (7.9%) patients with BA (mean age, 67.7±7.5 [SD]; range 45 - 77 years), 63/140 (45.0%) patients with AIS (mean age, 62.5±8.6 [SD]; range 36 - 69 years) and 66/140 (47.1%) patients with MIA (mean age, 63.5±7.9 [SD]; range 35 - 72 years). By comparison with AIS and MIA, significantly different CT features of BA included tumor size, solid component diameters, low CT attenuation of the ground-glass component, irregular shape, ill-defined peripheral opacity, pseudo-cavitation, and abnormal pulmonary vein. Ill-defined peripheral opacity (odds ratio, 1.060; 95% confidence interval [CI]: 1.020 - 1.380) and pseudo-cavitation (odds ratio, 1.236; 95% CI: 1.070 - 1.565) were variables independently associated with the diagnosis of BA.

CONCLUSION

CT provides morphological features that allow differentiating between BA and AIS-MIA among lung lesions presenting as GGNs.

Pemetrexed-Based Chemotherapy Is Inferior to Pemetrexed-Free Regimens in Thyroid Transcription Factor 1 (TTF-1)-Negative, EGFR/ALK-Negative Lung Adenocarcinoma: A Propensity Score Matched Pairs Analysis

INTRODUCTION

Thyroid transcription factor 1 (TTF-1) is a prognostic biomarker in lung adenocarcinoma; however, TTF-1-positive patients also display more favorable factors like actionable target mutations. In contrast, TTF-1-negative cancer is a poorly described entity. We performed a retrospective study to characterize a TTF-1-negative phenotype and to evaluate outcome depending on the chemotherapy regimen applied in the EGFR/ALK-negative population.

PATIENTS AND METHODS

Phenotypic traits were analyzed in 741 patients with evaluable TTF-1 expression status, among them 529 patients with platinum-based first-line chemotherapy, with disease diagnosed between 2009 and 2016 at a tertiary referral university hospital. The influence of TTF-1 and several cofactors on progression-free survival and overall survival (OS) were analyzed using a 1:1 propensity score matching model, depending on the platinum doublet chemotherapy's incorporating pemetrexed or not, with subsequent Cox regression.

RESULTS

TTF-1 negativity implied a distinct cancer phenotype with the predominance of male sex, worse Eastern Cooperative Oncology Group performance status, greater metastatic burden at primary diagnosis, and more adrenal gland metastases. These patients had improved progression-free survival (hazard ratio, 0.42; P = .001) and OS (hazard ratio, 0.40; P < .001) when gemcitabine-, taxane-, or vinorelbine-based regimens were provided instead of pemetrexed. None of the regimens was superior in TTF-1-positive patients with regard to OS. Overall, TTF-1 expression was strongly prognostic with a substantial increase in progression-free survival (hazard ratio, 0.54; P < .001) and OS (hazard ratio, 0.53; P < .001).

CONCLUSION

TTF-1 negativity is associated with a distinct cancer phenotype. Incorporation of this biomarker may be helpful when choosing an appropriate therapy regimen.

Minimizing residual occult nodal metastasis in NSCLC: recent advances, current status and controversies

Introduction: Nodal involvement in lung cancer is a significant determinant of prognosis and treatment management. New evidence exists regarding the management of occult lymph node metastasis and residual disease in the fields of imaging, mediastinal staging, and operative management.Areas covered: This review summarizes the latest body of knowledge on the identification and management of occult lymph node metastasis in NSCLC. We focus on tumor-specific characteristics; imaging modalities; invasive mediastinal staging; and operative management including, technique, degree of resection, and lymph node examination.Expert opinion: Newly identified risk-factors associated with nodal metastasis including tumor histology, location, radiologic features, and metabolic activity are not included in professional societal guidelines due to the heterogeneity of their reporting and uncertainty on how to adopt them into practice. Imaging as a sole diagnostic method is limited. We recommend confirmation with invasive mediastinal staging. EBUS-FNA is the best initial method, but adoption has not been uniform. The diagnostic algorithm is less certain for re-staging of mediastinal nodes after neoadjuvant therapy. Mediastinal node sampling during lobectomy remains the gold-standard, but evidence supports the use of minimally invasive techniques. More study is warranted regarding sublobar resection. No consensus exists regarding lymph node examination, but new evidence supports reexamination of current quality metrics.

Expansion of the Concept of Micropapillary Adenocarcinoma to Include a Newly Recognized Filigree Pattern as Well as the Classical Pattern Based on 1468 Stage I Lung Adenocarcinomas

INTRODUCTION

The classical micropapillary (MIP) pattern is defined in the 2015 WHO classification as tumor cells growing in papillary tufts forming florets that lack fibrovascular cores, and it is associated with poor prognosis. We observed a novel pattern that we termed a filigree MIP pattern and investigated its relationship with the classical MIP pattern.

METHODS

Filigree pattern was defined as tumor cells growing in delicate, lace-like, narrow stacks of cells without fibrovascular cores. We required at least three piled-up nuclei from the alveolar wall basal layer, with a breadth of up to three cells across. To assess the relationship of the filigree pattern with the classical MIP pattern, we documented their frequencies in the context of the clinical and pathologic characteristics of 1468 stage I invasive adenocarcinomas, including survival analysis using cumulative incidence of recurrence by competing risks.

RESULTS

We observed the filigree MIP pattern in 35% of cases. By including the filigree pattern as an MIP pattern, we identified 57 more MIP predominant cases in addition to the previously diagnosed 87 MIP predominant adenocarcinomas. These 57 cases were reclassified from papillary (n = 37), acinar (n = 16), and solid (n = 4) predominant adenocarcinoma, respectively. Of the 144 MIP predominant adenocarcinomas, the filigree predominant MIP pattern (n = 78) showed a poor prognosis like the classical predominant MIP pattern (n = 66) (p = 0.464). In addition, like the classical MIP pattern (p = 0.010), even a small amount (≥5%) of filigree MIP pattern was significantly associated with worse cumulative incidence of recurrence (p = 0.001) in multivariable analysis.

CONCLUSION

The frequent association with the classical MIP pattern and the similar poor prognosis supports inclusion of the filigree pattern in the MIP pattern subtype.

Identification of differentially expressed genes between primary lung cancer and lymph node metastasis via bioinformatic analysis

Lung cancer (LC), with its high morbidity and mortality rates, is one of the most widespread and malignant neoplasms. Mediastinal lymph node metastasis (MLNM) severely affects postoperative survival of patients with LC. Additionally, the molecular mechanisms of LC with MLNM (MM LC) remain not well understood. To identify the key biomarkers in its carcinogenesis and development, the datasets GSE23822 and GSE13213 were obtained from the Gene Expression Omnibus database. The differentially expressed genes (DEGs) were identified, and the Database for Annotation, Visualization and Integrated Discovery was used to perform functional annotations of DEGs. Search Tool for the Retrieval of Interacting Genes and Cytoscape were utilized to obtain the protein-protein interaction (PPI) network, and to analyze the most significant module. Subsequently, a Kaplan-Meier plotter was used to analyze overall survival (OS). Additionally, one co-expression network of the hub genes was obtained from cBioPortal. A total of 308 DEGs were identified in the two microarray datasets, which were mainly enriched during cellular processes, including the Gene Ontology terms ‘cell’, ‘catalytic activity’, ‘molecular function regulator’, ‘signal transducer activity’ and ‘binding’. The PPI network was composed of 315 edges and 167 nodes. Its significant module had 11 hub genes, and high expression of actin β, MYC, arginine vasopressin, vesicle associated membrane protein 2 and integrin subunit β1, and low expression of NOTCH1, synaptojanin 2 and intersectin 2 were significantly associated with poor OS. In summary, hub genes and DEGs presented in the present study may help identify underlying targets for diagnostic and therapeutic methods for MM LC.

Occult mediastinal lymph node metastasis in FDG-PET/CT node-negative lung adenocarcinoma patients: Risk factors and histopathological study

BACKGROUND

The aim of this study was to investigate predictive factors of occult mediastinal lymph node metastasis (MLNM) in preoperative 18 F-fluorodeoxy-glucose PET/CT node-negative lung adenocarcinoma patients.

METHODS

We reviewed the clinical data and PET/CT parameters of 360 consecutive pulmonary adenocarcinoma patients who were scheduled to undergo anatomical pulmonary resection and systemic mediastinal node dissection. The nodal metastasis was pathologically defined and all resected tumors were classified according to the 2011 IASLC/ATS/ERS classification. Univariate and multivariate analysis were conducted to evaluate the associations between clinicopathological variables and MLNM.

RESULTS

Of all 360 patients, 54 (15.0%) had pathological N2 diseases. The serum CEA level, nodule type, hilar nodal SUVmax, tumor SUVmax, size, location and histologic subtype were associated with MLNM significantly on univariate analysis. On multivariate analysis, CEA ≥ 5.0 ng/mL (P < 0.001), solid nodule (P = 0.012), tumor SUVmax ≥ 3.7 (P < 0.027), hilar nodal SUVmax ≥ 2.0 (P < 0.001) and centrally located tumor (P = 0.035) were independent risk factors for MLNM. The area under the ROC curve (AUC) for tumor SUVmax and hilar nodal SUVmax in predicting MLNM was 0.764 and 0.730, respectively, and the combined use of five factors yielded a higher AUC of 0.885.

CONCLUSION

Increased primary tumor and hilar lymph node SUVmax, solid nodule, centrally located tumor and increased CEA level predicted the increased risk of mediastinal lymph node metastasis. Combined use of these factors improved the diagnostic capacity for predicting N2 disease preoperatively. Invasive mediastinal staging should be considered for patients with these risk factors, even those with a negative mediastinum on PET/CT.

Influences of scan-position on clinical ultra-high-resolution CT scanning: a preliminary study

The aim of this study is to access influences of scan-position on clinical ultra-high-resolution CT scanning. We proposed a breath-hold assisted ultra-high-resolution scanning technology (scan scheme G) and compared with scan scheme A (regular CT plain scan) and scheme B (1024 ultra-high-resolution scan with patients stay in supine position). A total of 30 patients with fGGO were included in this study. Three highly experienced chest imaging doctors were employed to score the image and to select regions of interest (ROIs) for CT value and signal-to-noise ratio (SNR) calculation. In comparison with scan A and B, this new scan scheme G shows more clear CT images and higher SNRs at overall lung field (the p-values of A versus G and B versus G are 0.041 and 0.065, respectively). These findings suggest that scan-G provides a better image quality and contributes significantly to clinical detection accuracy of fGGO.

Precision Medicine in Non-Small Cell Lung Cancer: Current Standards in Pathology and Biomarker Interpretation

Non-small cell lung cancer (NSCLC) has become a prominent example of precision medicine among solid tumor malignancies. Clinical management of NSCLC now depends on surgical, chemotherapeutic, and radiation treatment regimens based on pathologic findings and clinical staging as well as targeted therapies based on molecular profiling. As molecular testing becomes increasingly important, preserving tissue for this purpose while rendering an accurate histologic diagnosis becomes a key consideration, particularly in advanced-stage NSCLC, in which small biopsy samples or aspirates are often the only specimen available. Next-generation sequencing panels are a powerful method of providing information relevant for both standard-of-care and investigational treatment options. However, taking advantage of the abundance of information gleaned from these panels requires careful annotation, prioritization, and reporting of molecular findings and their clinical significance. Although molecular profiling has traditionally relied on direct sampling of neoplastic tissue, blood-based diagnostics now offer the potential to provide some clinically useful information noninvasively.

Quantitative CT analysis of pulmonary nodules for lung adenocarcinoma risk classification based on an exponential weighted grey scale angular density distribution feature

BACKGROUND AND OBJECTIVES

To improve lung nodule classification efficiency, we propose a lung nodule CT image characterization method. We propose a multi-directional feature extraction method to effectively represent nodules of different risk levels. The proposed feature combined with pattern recognition model to classify lung adenocarcinomas risk to four categories: Atypical Adenomatous Hyperplasia (AAH), Adenocarcinoma In Situ (AIS), Minimally Invasive Adenocarcinoma (MIA), and Invasive Adenocarcinoma (IA).

METHODS

First, we constructed the reference map using an integral image and labelled this map using a K-means approach. The density distribution map of the lung nodule image was generated after scanning all pixels in the nodule image. An exponential function was designed to weight the angular histogram for each component of the distribution map, and the features of the image were described. Then, quantitative measurement was performed using a Random Forest classifier. The evaluation data were obtained from the LIDC-IDRI database and the CT database which provided by Shanghai Zhongshan hospital (ZSDB). In the LIDC-IDRI, the nodules are categorized into three configurations with five ranks of malignancy ("1" to "5"). In the ZSDB, the nodule categories are AAH, AIS, MIA, and IA.

RESULTS

The average of Student's t-test p-values were less than 0.02. The AUCs for the LIDC-IDRI database were 0.9568, 0.9320, and 0.8288 for Configurations 1, 2, and 3, respectively. The AUCs for the ZSDB were 0.9771, 0.9917, 0.9590, and 0.9971 for AAH, AIS, MIA and IA, respectively.

CONCLUSION

The experimental results demonstrate that the proposed method outperforms the state-of-the-art and is robust for different lung CT image datasets.

Early effective treatment of small pulmonary nodules with video-assisted thoracoscopic surgery combined with CT-guided dual-barbed hookwire localization

PURPOSE

To assess the feasibility of computed tomography (CT)-guided localization using a specific long dual-barbed hookwire in resection of pulmonary nodules with the size of 20mm or less by video-assisted thoracoscopic surgery (VATS) and to discuss the necessity of early treatment of small pulmonary nodules by VATS.

RESULTS

All the nodules were successfully localized with hook wire under CT guidance. The 34 nodules had a mean diameter of 8.9 ± 3.8 mm and a mean distance from the most superficial edge of the nodules to the visceral pleura of 21.4 ± 12.4 mm. The mean length of time for CT-guided percutaneous localization was 9.0 ± 3.8 minutes. Asymptomatic pneumothorax and parenchyma hemorrhage were observed in 1 patient (3.2%) and 5 patients (16.1%), respectively. VATS successfully resected all the lesions after localization. The mean VATS operation time was 2.6 ± 1.2 hours (range, 0.8-5.2 hours). 24 (70.6%) malignant nodules and 10 benign nodules were discovered after surgery.

MATERIALS AND METHODS

Between March 2012 and August 2014, 31 patients with 34 small pulmonary lesions underwent CT-guided hook wire localization and VATS resection. The efficacy of preoperative localization was evaluated in terms of procedure time, VATS success rate and associated complications of localization. And the pathology and imaging diagnosis of all nodules were recorded.

CONCLUSIONS

The CT-guided Hook-wire localization for pulmonary nodules with the size of 20 mm or less is an effective and safe technique to assist VATS. Once small pulmonary nodules change in size or number, it is necessary to treat in an early and aggressive way with minimally invasive surgery.

Multimodality therapy in subclassified stage IIIA-N2 non-small cell lung cancer patients according to the Robinson classification: heterogeneity and management

Background

Non-small cell lung cancer (NSCLC) with mediastinal lymph node involvement (N2) is a heterogeneous entity. The objective of this analysis is to investigate the results of treatment strategies for N2-positive patients.

Methods

Retrospective study (2009-2014) of 104 consecutive patients with stage IIIA-N2 NSCLC classified according to the Robinson classification (IIIA1-IIIA4) and treated within a multimodality treatment regime.

Results

The Robinson subgroups were: IIIA1 (n=27), IIIA3 (n=60) and IIIA4 (n=17). We had no stage IIIA2 samples because we did not perform an intraoperative frozen section of lymph nodes. Surgical resection with systematic lymph node dissection was performed in all patients with stage IIIA1 (n=27). After chemotherapy or chemo-/radiotherapy, 53.3% of patients in stage IIIA3 (n=32) and 11.7% of patients in stage IIIA4 (n=2) underwent surgery with curative intention. R0 was achieved in 92.6% in stage IIIA1, 93.8% in stage IIIA3 and 100% in stage IIIA4. The 30-day mortality was 3.2%. The overall median survival was 31.7 months (5-year survival was 30.5%). There were no significant differences (P=0.583) in survival regarding the Robinson subgroups. Patients who underwent tumour resection had significantly better median survival (39.8 vs. 19.6 months; P=0.014) compared to patients treated conservatively. Deviation from the interdisciplinary recommended therapy (12%) led to a reduced median survival (11.4 vs. 31.8 months; P=0.137).

Conclusions

N2-patients should be subclassified according to the Robinson classification and discussed in the tumour board. Surgical resection should be recommended in specific cases of N2-disease (non-bulky, sensitivity to systemic treatment).

Radiomics Approach to Prediction of Occult Mediastinal Lymph Node Metastasis of Lung Adenocarcinoma

OBJECTIVE

The purpose of this study was to evaluate the prognostic impact of radiomic features from CT scans in predicting occult mediastinal lymph node (LN) metastasis of lung adenocarcinoma.

MATERIALS AND METHODS

A total of 492 patients with lung adenocarcinoma who underwent preoperative unenhanced chest CT were enrolled in the study. A total of 300 radiomics features quantifying tumor intensity, texture, and wavelet were extracted from the segmented entire-tumor volume of interest of the primary tumor. A radiomics signature was generated by use of the relief-based feature method and the support vector machine classification method. A ROC regression curve was drawn for the predictive performance of radiomics features. Multivariate logistic regression models based on clinicopathologic and radiomics features were compared for discriminating mediastinal LN metastasis.

RESULTS

Clinical variables (sex, tumor diameter, tumor location) and predominant subtype were risk factors for pathologic mediastinal LN metastasis. The accuracy of radiomics signature for predicting mediastinal LN metastasis was 91.1% in ROC analysis (AUC, 0.972; sensitivity, 94.8%; specificity, 92%). Radiomics signature (Akaike information criterion [AIC] value, 80.9%) showed model fit superior to that of the clinicohistopathologic model (AIC value, 61.1%) for predicting mediastinal LN metastasis.

CONCLUSION

The radiomics signature of a primary tumor based on CT scans can be used for quantitative and noninvasive prediction of occult mediastinal LN metastasis of lung adenocarcinoma.

Ground glass opacities: Imaging, pathology, and gene mutations

BACKGROUND

Lung cancer can be detected in its early stages with computed tomography (CT). Early lung adenocarcinoma often is displayed as ground glass opacity (GGO), an entity that has been well studied over the past decade. However, few studies have focused on the correlation between CT characteristics and pathologic subtype of GGO. We aimed to explore the correlation between CT characteristics, pathologic subtype, and gene mutation associated with GGO in an effort to aid in the treatment of lung adenocarcinoma.

METHODS

In this retrospective study, patients with GGO who underwent surgery in our institution between 2013 and 2016 were included. Patients were divided into 2 groups on the basis of CT characteristics: group 1, diameter <20 mm and solid component <50%; and group 2, diameter ≥20 mm or solid component ≥50%. Differences in pathologic subtype and gene mutation pattern between groups were compared using the χ² test. The correlation between pathologic subtype and epidermal growth factor receptor (EGFR) mutation was also tested using the χ² test.

RESULTS

A total of 1018 cases (408 in group 1, 610 in group 2) were included; of these, 544 were tested for the EGFR gene mutation. There was a significant difference in predominant subtype (P < .001) and all included subtypes (P = .044) between the groups. Of 59 cases with the pathologic subtype of micropapillary or solid, 57 were in group 2. The EGFR gene mutation rate was significantly higher in group 2 than group 1 (P < .001) and significantly correlated with pathologic subtype (P < .001); adenocarcinoma in situ was the lowest (31.4%) and papillary was the highest (85.7%). EGFR mutation subtype did not significantly differ between groups (P = .499).

CONCLUSIONS

CT characteristics of GGO significantly correlated with pathologic subtype and gene mutation rate. The EGFR mutation rate differed significantly among pathologic subtypes. GGOs with a diameter of <20 mm and with a solid component <50% seldom contain subtypes with poor prognosis (micropapillary and solid) and the EGFR mutation rate was significantly lower.

Predictors of recurrence and survival of pathological T1N0M0 invasive adenocarcinoma following lobectomy

BACKGROUND

This retrospective research was designed to investigate the relationship between pT1N0M0 invasive adenocarcinoma (IADC) harboring solid (SOL) and/or micropapillary (MIP) components and its prognosis following lobectomy.

METHODS

Clinical data of pT1N0M0 IADC patients were retrospectively collected from Shanghai Chest Hospital. Survival curves were plotted by Kaplan-Meier methods. Multivariable cox regressions were conducted to discover the independent risk factors of recurrence-free survival (RFS) and overall survival (OS), through which nomograms were performed to visualize the risk of recurrences and outcomes in personalized information.

RESULTS

Totally, 1965 patients were enrolled, including 248 harboring SOL/MIP and 1717 not. IADC demonstrated worse 5-year RFS (81.9 vs. 92.2%, p < 0.001) and OS (85.7 vs. 94.4%, p < 0.001) when harboring SOL and/or MIP components. And this status became an independent factor associated with poorer RFS (HR 2.445, 95% CI 1.565-3.821, p < 0.001) and OS (HR 2.139, 95% CI 1.180-3.878, p = 0.012) instead of novel classification of IADC predominant patterns. No difference existed between SOL/MIP predominant and minor patterns. In addition, age > 60, smoking, post-chemotherapy and T1b were all indicating poorer RFS and smoking was also related with worse OS. The c-indexes of nomograms were 0.723 for RFS (95% CI, 0.662-0.784) and 0.703 for OS (95% CI, 0.629-0.777) respectively.

CONCLUSIONS

Once the pT1N0M0 IADC harboring SOL/MIP, it strongly indicated the worse clinical recurrence and survival outcome, no matter whether the SOL and/or MIP was predominant. Smoking was correlated with worse prognosis for those patients. Age > 60 and stage T1b also indicated poorer RFS. Whether post-chemotherapy was harmful to pT1N0M0 IADC patients needed further research.

Epigenetically Regulated Chromosome 14q32 miRNA Cluster Induces Metastasis and Predicts Poor Prognosis in Lung Adenocarcinoma Patients

Most lung cancer deaths are related to metastases, which indicates the necessity of detecting and inhibiting tumor cell dissemination. Here, we aimed to identify miRNAs involved in metastasis of lung adenocarcinoma as prognostic biomarkers and therapeutic targets. To that end, lymph node metastasis-associated miRNAs were identified in The Cancer Genome Atlas lung adenocarcinoma patient cohort (sequencing data; n = 449) and subsequently validated by qRT-PCR in an independent clinical cohort (n = 108). Overexpression of miRNAs located on chromosome 14q32 was associated with metastasis in lung adenocarcinoma patients. Importantly, Kaplan-Meier analysis and log-rank test revealed that higher expression levels of individual 14q32 miRNAs (mir-539, mir-323b, and mir-487a) associated with worse disease-free survival of never-smoker patients. Epigenetic analysis including DNA methylation microarray data and bisulfite sequencing validation demonstrated that the induction of 14q32 cluster correlated with genomic hypomethylation of the 14q32 locus. CRISPR activation technology, applied for the first time to functionally study the increase of clustered miRNA levels in a coordinated manner, showed that simultaneous overexpression of 14q32 miRNAs promoted tumor cell migratory and invasive properties. Analysis of individual miRNAs by mimic transfection further illustrated that miR-323b-3p, miR-487a-3p, and miR-539-5p significantly contributed to the invasive phenotype through the indirect regulation of different target genes. In conclusion, overexpression of 14q32 miRNAs, associated with the respective genomic hypomethylation, promotes metastasis and correlates with poor patient prognosis in lung adenocarcinoma.Implications: This study points to chromosome 14q32 miRNAs as promising targets to inhibit tumor cell dissemination and to predict patient prognosis in lung adenocarcinoma. Mol Cancer Res; 16(3); 390-402. ©2018 AACR.

The Molecular Pathology of Lung Cancer

Advances in lung cancer genomics have revolutionized the diagnosis and treatment of this heterogeneous and clinically significant group of tumors. This article provides a broad overview of the most clinically relevant oncogenic alterations in common and rare lung tumors, with an emphasis on the pathologic correlates of the major oncogenic drivers, including EGFR, KRAS, ALK, and MET. Illustrations emphasize the morphologic diversity of lung adenocarcinoma, including genotype-phenotype correlations of genomic evolution in tumorigenesis. Molecular diagnostic approaches, including PCR-based testing, massively parallel sequencing, fluorescence in situ hybridization, and immunohistochemistry are reviewed.

Driver genes in non-small cell lung cancer: Characteristics, detection methods, and targeted therapies

Lung cancer is one of the most common causes of cancer-related death in the world. The large number of lung cancer cases is non-small cell lung cancer (NSCLC), which approximately accounting for 75% of lung cancer. Over the past years, our comprehensive knowledge about the molecular biology of NSCLC has been rapidly enriching, which has promoted the discovery of driver genes in NSCLC and directed FDA-approved targeted therapies. Of course, the targeted therapies based on driver genes provide a more exact option for advanced non-small cell lung cancer, improving the survival rate of patients. Now, we will review the landscape of driver genes in NSCLC including the characteristics, detection methods, the application of target therapy and challenges.