Coexistence of FTCs resulted in a further negative impact on postoperative prognosis among MPC-positive adenocarcinomas and should be considered for upstaging the p-T factor and during evaluation of surgical margins.

Lung adenocarcinomas with H-FLAC features possess the potential for multidirectional differentiation, and are not strongly associated with known major driver gene mutations.

Background: Elastography is a relatively new technology that can generate images reflective of tissue stiffness (elasticity). Neoplastic tissue is usually stiffer than normal structures. Objectives: The aim of this study was to evaluate the feasibility and utility of elastography when combined with convex-probe endobronchial ultrasound (CP-EBUS) for predicting and localizing metastatic lymph nodes during endobronchial ultrasound with transbronchial needle aspiration (EBUS-TBNA). Methods: Consecutive results of endobronchial elastography of lymph nodes performed using EBUS- TBNA were prospectively collected and retrospectively analyzed. Elastography images were acquired as JPEG images and also recorded as video clips. Stiff area ratios [(stiff areas as blue pixels) / (lymph node areas as region of interest pixels)] for each lymph node determined by elastography were collated with the results of pathological diagnosis. We also performed elastography of surgically resected lymph nodes and compared image findings with pathological sections. Results: We evaluated 49 lymph nodes in 21 patients by CP-EBUS. There were 16 metastatic nodes (10 lung cancer metastases and 6 metastases from extrathoracic malignancies). Mean stiff area ratios were significantly greater for metastatic lymph nodes (0.478) than for benign nodes (0.216; p = 0.0002). Using a cutoff value of 0.311 for stiff area ratios, the sensitivity and specificity for predicting metastatic disease were 0.81 and 0.85, respectively. The stiff area was histologically compatible with metastatic distribution in surgically resected lymph nodes. Conclusions: Endobronchial elastography is feasible for lymph nodes when combined with CP-EBUS. Stiff area ratios are useful for predicting metastatic lymph nodes, which may be an efficient guide for TBNA.

No functional advantage for segmentectomy was observed during long-term follow-up, possibly due to compensatory lung growth after lobectomy.

Patients with idiopathic pulmonary fibrosis (IPF) have higher risk of developing lung cancer, for example, squamous cell carcinoma (SCC), and show poor prognosis, while the molecular basis has not been fully investigated. Here we conducted DNA methylome analysis of lung SCC using 20 SCC samples with/without IPF, and noncancerous lung tissue samples from smokers/nonsmokers, using Infinium HumanMethylation 450K array. SCC was clustered into low‐ and high‐methylation epigenotypes by hierarchical clustering analysis. Genes hypermethylated in SCC significantly included genes targeted by polycomb repressive complex in embryonic stem cells, and genes associated with Gene Ontology terms, for example, “transcription” and “cell adhesion,” while genes hypermethylated specifically in high‐methylation subgroup significantly included genes associated with “negative regulation of growth.” Low‐methylation subgroup significantly correlated with IPF (78%, vs. 17% in high‐methylation subgroup, p = 0.04), and the correlation was validated by additional Infinium analysis of SCC samples (n = 44 in total), and data from The Cancer Genome Atlas (n = 390). The correlation between low‐methylation subgroup and IPF was further validated by quantitative methylation analysis of marker genes commonly hypermethylated in SCC (HOXA2, HOXA9 and PCDHGB6), and markers specifically hypermethylated in high‐methylation subgroup (DLEC1, CFTR, MT1M, CRIP3 and ALDH7A1) in 77 SCC cases using pyrosequencing (p = 0.003). Furthermore, low‐methylation epigenotype significantly correlated with poorer prognosis among all SCC patients, or among patients without IPF. Multivariate analysis showed that low‐methylation epigenotype is an independent predictor of poor prognosis. These may suggest that lung SCC could be stratified into molecular subtypes with distinct prognosis, and low‐methylation lung SCC that significantly correlates with IPF shows unfavorable outcome.