Deep learning-based respiratory muscle segmentation as a potential imaging biomarker for respiratory function assessment.

Respiratory diseases significantly affect respiratory function, making them a considerable contributor to global mortality. The respiratory muscles play an important role in disease prognosis; as such, quantitative analysis of the respiratory muscles is crucial to assess the status of the respiratory system and the quality of life in patients. In this study, we aimed to develop an automated approach for the segmentation and classification of three types of respiratory muscles from computed tomography (CT) images using artificial intelligence. With a dataset of approximately 600,000 thoracic CT images from 3,200 individuals, we trained the model using the Attention U-Net architecture, optimized for detailed and focused segmentation. Subsequently, we calculated the volumes and densities from the muscle masks segmented by our model and performed correlation analysis with pulmonary function test (PFT) parameters. The segmentation models for muscle tissue and respiratory muscles obtained dice scores of 0.9823 and 0.9688, respectively. The classification model, achieving a generalized dice score of 0.9900, also demonstrated high accuracy in classifying thoracic region muscle types, as evidenced by its F1 scores: 0.9793 for the pectoralis muscle, 0.9975 for the erector spinae muscle, and 0.9839 for the intercostal muscle. In the correlation analysis, the volume of the respiratory muscles showed a strong correlation with PFT parameters, suggesting that respiratory muscle volume may serve as a potential novel biomarker for respiratory function. Although muscle density showed a weaker correlation with the PFT parameters, it has a potential significance in medical research.

Impact of adjuvant chemotherapy on patients with stage IB non-small cell lung cancer with visceral pleural invasion.

Background: Adjuvant chemotherapy has reduced the risk of recurrence and death in stage IB non-small cell lung cancer (NSCLC) with high-risk factors; however, the impact of visceral pleural invasion (VPI) on outcomes in stage IB NSCLC treated with adjuvant chemotherapy remains controversial. The aim of this study was to explore the clinical and prognostic significance of adjuvant chemotherapy for stage IB (1-4 cm) NSCLC with VPI. Methods: This retrospective study included 251 patients admitted between January 2008 and May 2018 from four hospitals who underwent complete resection for Tumor-Node-Metastasis (TNM) 8th edition stage IB NSCLC with VPI. The relationship between adjuvant chemotherapy and overall survival (OS) or recurrence-free survival (RFS) was analyzed using the Kaplan-Meier method and Cox proportional hazards model. Results: Of 251 patients with stage IB NSCLC with VPI, 122 (48.6%) received adjuvant chemotherapy after surgical resection and 129 (51.4%) were placed under observation. Multivariable analysis showed that adjuvant chemotherapy was an independent predictor of RFS [adjusted hazard ratio (aHR), 0.57; 95% confidence interval (CI): 0.33-0.96; P=0.036]. A micropapillary pattern (aHR, 2.46; 95% CI: 1.33-4.55; P=0.004) and lymphovascular invasion (aHR, 2.86; 95% CI: 1.49-5.48; P=0.002) were associated with a higher risk of recurrence. Multivariable analysis also showed that adjuvant chemotherapy was an independent predictor of OS (aHR, 0.22; 95% CI: 0.09-0.58; P=0.002). In a subgroup analysis of patients with a tumor size of 1-3 cm, adjuvant chemotherapy was associated with improved RFS and OS, and this association was maintained even when patients with VPI had additional risk factors. Conclusions: Our study shows that adjuvant chemotherapy is appropriate for patients with stage IB (1-4 cm) NSCLC with VPI, and even those with smaller tumors (1-3 cm).

Mechanical ventilation in patients with idiopathic pulmonary fibrosis in Korea: a nationwide cohort study.

BACKGROUND/AIMS: The prognosis of patients with idiopathic pulmonary fibrosis (IPF) and respiratory failure requiring mechanical ventilation is poor. Therefore, mechanical ventilation is not recommended. Recently, outcomes of mechanical ventilation, including those for patients with IPF, have improved. The aim of this study was to investigate changes in the use of mechanical ventilation in patients with IPF and their outcomes over time. METHODS: This retrospective, observational cohort study used data from the National Health Insurance Service database. Patients diagnosed with IPF between January 2011 and December 2019 who were placed on mechanical ventilation were included. We analyzed changes in the use of mechanical ventilation in patients with IPF and their mortality using the Cochran- Armitage trend test. RESULTS: Between 2011 and 2019, 1,227 patients with IPF were placed on mechanical ventilation. The annual number of patients with IPF with and without mechanical ventilation increased over time. However, the ratio was relatively stable at approximately 3.5%. The overall hospital mortality rate was 69.4%. There was no improvement in annual hospital mortality rate. The overall 30-day mortality rate was 68.7%, which did not change significantly. The overall 90-day mortality rate was 85.3%. The annual 90-day mortality rate was decreased from 90.9% in 2011 to 83.1% in 2019 (p = 0.028). CONCLUSION: Despite improvements in intensive care and ventilator management, the prognosis of patients with IPF receiving mechanical ventilation has not improved significantly.

Real-world first-line afatinib for advanced EGFR mutation-positive non-small cell lung cancer in Korea: updated survival data.

Background: Data from clinical trials and real-world studies show that afatinib is effective in treating non-small cell lung cancer (NSCLC) harboring activating mutations in the epidermal growth factor receptor (EGFR) gene. A previous analysis of patients enrolled in the Korean Academy of Tuberculosis and Respiratory Disease (KATRD) EGFR cohort showed that first-line afatinib was well tolerated and effectiveness results were encouraging. At the time of the previous analysis, survival data were not mature. Here we briefly present updated survival data from the cohort. Methods: The study was a retrospective, multicenter (15 sites) review of electronic records of Korean adult patients (aged >20 years) with advanced EGFR mutation-positive NSCLC who initiated first-line afatinib (N=421). Progression-free survival (PFS) and overall survival (OS) were evaluated using Kaplan-Meier survival curves. Results: Overall, median PFS was 20.2 months and median OS was 48.6 months. OS rates at 36 and 60 months were 60.1% and 42.3%, respectively. Presence vs. absence of baseline brain metastases was associated with significantly reduced median PFS (14.9 vs. 28.0 months; P<0.001) and median OS (32.2 vs. 65.6 months; P<0.001). The presence of common baseline EGFR mutations (Del19, L858R) was associated with significantly prolonged median OS (49.6 vs. 30.1 months; P=0.017). In patients stratified by the presence/absence of T790M EGFR mutation, the T790M mutation was associated with significantly reduced median PFS (P=0.0005) but there was no significant difference between groups in survival (P=0.263). There were no significant differences in PFS or OS for patients stratified by afatinib dose reduction or by age group (<70 vs. ≥70 years). Conclusions: Afatinib was effective in Korean patients with EGFR mutation-positive NSCLC with median OS over 4 years. The presence of baseline brain metastases and/or uncommon EGFR mutations were associated with reduced survival. In the absence of baseline brain metastases, median OS was more than 5 years.

Real-World Treatment Outcomes and Safety of Afatinib in Advanced Squamous Cell Lung Cancer Progressed after Platinum-Based Doublet Chemotherapy and Immunotherapy (SPACE Study).

This study aimed to evaluate treatment outcomes and safety of afatinib in patients with squamous cell carcinoma of the lung (LSCC) who progressed after chemotherapy and immunotherapy. We recruited patients both retrospectively and prospectively and collected the outcomes and safety data. Additionally, we performed next-generation sequencing using tumor tissue and/or plasma to explore potential molecular biomarkers. Altogether, 42 patients were included in the final analysis. The median number of prior treatments was three (range 1-8), and the median TTF was 2.1 months. Objective response rate and disease control rate were 16.2% and 59.5%, respectively, and median duration of response was 4.0 months among response evaluable patients (n = 37). Treatment-related adverse events (TRAEs, including diarrhea, stomatitis, and paronychia) occurred in 22 (52.3%) patients; however, most were grade 2 or lower, and only 5 cases were grade 3. TRAEs led to dose modification in 17 (40.5%) and discontinuation in 4 (9.5%) patients. The TTF in patients with ERBB2 mutations was significantly longer than that in patients without (6.8 vs. 2.1 months, p = 0.045). Our results highlight that afatinib is a reasonable treatment option in terms of effectiveness and safety, and ERBB2 mutation can be used as a predictive biomarker in clinical settings.

Perioperative immunotherapy in stage IB-III non-small cell lung cancer: a critical review of its rationale and considerations.

Lung cancer is a dismal disease as a leading cause of overall cancer death, but the development of immune checkpoint inhibitors (ICIs) in driver gene mutation negative metastatic non-small cell lung cancer (NSCLC) is changing the paradigm of lung cancer treatment. Recently, ICIs are expanding their treatment area to early-stage NSCLC and ICIs have also changed their treatment strategies of such patients. And it is important to appropriately select patients with resectable early-stage lung cancer through a multidisciplinary team approach and decrease the tumor relapse rate in the ICIs era. In this review article, we discuss the recently released neoadjuvant and adjuvant data of ICIs, their treatment rationale, and unmet needs in the treatment of early-stage NSCLC.

Risk factor analysis of the development of severe radiation pneumonitis in patients with non-small cell lung cancer treated with curative radiotherapy, with focus on underlying pulmonary disease.

BACKGROUND: We aim to identify the multifaceted risk factors that can affect the development of severe radiation pneumonitis (RP) in patients with non-small cell lung cancer (NSCLC) treated with curative high-dose radiotherapy with or without concurrent chemotherapy. METHODS: We retrospectively reviewed the medical records of 175 patients with stage-I-III NSCLC treated with curative thoracic X-ray radiotherapy at the Korea University Guro Hospital between June 2019 and June 2022. Treatment-related complications were evaluated using the Common Terminology Criteria for Adverse Events (version 4.03). RESULTS: The median follow-up duration was 15 months (range: 3-47 months). Idiopathic pulmonary fibrosis (IPF) as an underlying lung disease (P < 0.001) and clinical stage, regarded as the concurrent use of chemotherapy (P = 0.009), were associated with a high rate of severe RP. In multivariate analyses adjusting confounding variables, the presence of IPF as an underlying disease was significantly associated with severe RP (odds ratio [95% confidence interval] = 48.4 [9.09-347]; P < 0.001). In a subgroup analysis of stage-I-II NSCLC, the incidence of severe RP in the control, chronic obstructive pulmonary disease (COPD), and IPF groups was 3.2%, 4.3%, and 42.9%, respectively (P < 0.001). The incidence of severe RP was 15.2%, 10.7%, and 75.0% in the control, COPD, and IPF groups, respectively (P < 0.001) in the stage-III NSCLC group. CONCLUSIONS: This study revealed that IPF as an underlying lung disease and the concurrent use of chemotherapy are associated with a high rate of severe RP. In contrast, COPD did not increase the risk of pulmonary toxicity after receiving curative high-dose radiotherapy.

Deep learning-based pectoralis muscle volume segmentation method from chest computed tomography image using sagittal range detection and axial slice-based segmentation.

The pectoralis muscle is an important indicator of respiratory muscle function and has been linked to various parenchymal biomarkers, such as airflow limitation severity and diffusing capacity for carbon monoxide, which are widely used in diagnosing parenchymal diseases, including asthma and chronic obstructive pulmonary disease. Pectoralis muscle segmentation is a method for measuring muscle volume and mass for various applications. The segmentation method is based on deep-learning techniques that combine a muscle area detection model and a segmentation model. The training dataset for the detection model comprised multichannel images of patients, whereas the segmentation model was trained on 7,796 cases of the computed tomography (CT) image dataset of 1,841 patients. The dataset was expanded incrementally through an active learning process. The performance of the model was evaluated by comparing the segmentation results with manual annotations by radiologists and the volumetric differences between the CT image datasets of the same patients. The results indicated that the machine learning model is promising in segmenting the pectoralis major muscle, with good agreement between the automatic segmentation and manual annotations by radiologists. The training accuracy and loss values of the validation set were 0.9954 and 0.0725, respectively, and for segmentation, the loss value was 0.0579. This study shows the potential clinical usefulness of the machine learning model for pectoralis major muscle segmentation as a quantitative biomarker for various parenchymal and muscular diseases.

Korean Real-World Data on Patients With Unresectable Stage III NSCLC Treated With Durvalumab After Chemoradiotherapy: PACIFIC-KR.

INTRODUCTION: This study aimed to investigate real-world evidence for efficacy and safety of durvalumab consolidation (DC) after chemoradiotherapy (CRT) in patients with unresectable stage III NSCLC. METHODS: Patients with stage III NSCLC who started DC after CRT between September 2018 and December 2020 and were treated at five tertiary hospitals in the Republic of Korea were included. The primary end point was real-world progression-free survival (rwPFS). Secondary end points were overall survival, objective response rate, and adverse events including radiation pneumonitis (RP) and immune-related adverse events (irAEs). RESULTS: A total of 157 patients were enrolled. At the median follow-up of 19.1 months, median rwPFS of DC was 25.9 months (95% confidence interval: 16.5-35.4) and the 1-, 2-, and 3-year rwPFS rates were 59.4%, 51.8%, and 43.5%, respectively. The median overall survival was not mature, and objective response rate of DC was 51.0%. High programmed death-ligand 1 expression (≥50%) and development of RP requiring steroid treatment were significantly associated with longer (p = 0.043) and shorter rwPFS (p = 0.036), respectively. RP, RP requiring steroid treatment, and irAEs developed in 57 (36.3%), 42 (26.8%), and 53 (33.8%) patients, respectively. Among peripheral blood cell counts at the initiation of DC, a high derived monocyte-to-lymphocyte ratio was the most significant risk factor for the development of RP requiring steroid treatment (OR 44.76, 95% CI: 8.89-225.43, p < 0.001) and irAEs (OR 2.85, 95% CI: 1.27-6.41, p = 0.011). CONCLUSIONS: Compared with the outcome of the PACIFIC trial, these real-world data revealed favorable survival benefits of DC after CRT in patients with unresectable stage III NSCLC. Blood-based biomarkers could predict higher-grade RP and irAEs before the initiation of DC.

Association Between Air Pollution and Viral Infection in Severe Acute Exacerbation of Chronic Obstructive Pulmonary Disease.

BACKGROUND: Respiratory pathogen infections and air pollution are main causes of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Air pollution has a direct effect on the airway epithelial barrier and the immune system, which can have an influence on infection. However, studies on the relationship between respiratory infections and air pollutants in severe AECOPD are limited. Thus, the objective of this study was to investigate the correlation between air pollution and respiratory pathogen in severe AECOPD. METHODS: This multicenter observational study was conducted by reviewing electronic medical records of patients with AECOPD at 28 hospitals in South Korea. Patients were divided into four groups according to the comprehensive air-quality index (CAI) used in Korea. Identification rates of bacteria and viruses of each group were analyzed. RESULTS: Viral pathogens were identified in 270 (36.7%) of 735 patients. Viral identification rate was different (P = 0.012) according to air pollution. Specifically, the virus detection rate was 55.9% in the group of CAI 'D' with the highest air pollution. It was 24.4% in the group of CAI 'A' with the lowest air pollution. This pattern was clearly seen for influenza virus A (P = 0.042). When further analysis was performed with particulate matter (PM), the higher/lower the PM level, the higher/lower the virus detection rate. However, no significant difference was found in the analysis related to bacteria. CONCLUSION: Air pollution may make COPD patients more susceptible to respiratory viral infections, especially influenza virus A. Thus, on days with poor air quality, COPD patients need to be more careful about respiratory infections.

Understanding CDC's Vaccine Communication during the COVID-19 Pandemic and Its Effectiveness in Promoting Positive Attitudes toward the COVID-19 Vaccine.

The COVID-19 pandemic has imposed many communication challenges for public health authorities, especially communicating the safety, effectiveness, and importance of the COVID-19 vaccine. This study takes an integrative approach that includes a content analysis of COVID-19 vaccine-related messages from the CDC Facebook page and an experimental test of the effectiveness of the same types of vaccine-related messages on participants' attitudes toward the COVID-19 vaccine. Our findings from the content analysis show that gain-frame was used significantly more than loss-frame, and statistical evidence was more prevalent than narrative evidence in the CDC's COVID-19 vaccine-related messaging. Results from the experiment indicated that loss-framed, and messages with statistical evidence, may be more successful in promoting positive attitudes toward the COVID-19 vaccine.

A phase II, multicenter study of lazertinib as consolidation therapy in patients with locally advanced, unresectable, EGFR mutation-positive non-small cell lung cancer (stage III) who have not progressed following definitive, platinum-based, chemoradiation therapy (PLATINUM trial).

INTRODUCTION: The PACIFIC study demonstrated that durvalumab consolidation therapy significantly improved progression-free survival (PFS) and overall survival (OS) in patients with unresectable stage III non-small cell lung cancer (NSCLC) after concurrent chemoradiotherapy (CCRT). However, there was no clinical benefit in both PFS and OS in epidermal growth factor receptor (EGFR) mutation-positive patient groups in a post hoc exploratory analysis. Moreover, the clinical effects of immune checkpoint inhibitors (ICIs) in EGFR mutation-positive stage IV NSCLC were demonstrated to be poor. Personalized treatment according to the mutation status is also required in stage III NSCLC. Lazertinib, a third-generation EGFR tyrosine kinase inhibitor (TKI), is newly developed and approved for use in Korea. METHODS: This prospective, open, single-arm, multicenter, phase II clinical trial aims to evaluate the efficacy and safety of lazertinib as a consolidative therapy after CCRT treatment in unresectable, EGFR mutation-positive NSCLC stage III patients. The primary endpoint of this study is PFS, and the secondary endpoints are OS, objective response rate (ORR), duration of response (DoR), time to death or distant metastasis (TTDM), and safety profiles. DISCUSSION: Our study may extend the indications for third-generation EGFR-TKIs to treat patients with stage III NSCLC. Moreover, using this drug to treat stage III NSCLC would emphasize the value of mutation analysis and personalized medicine.

Open-label, multi-center, phase II study of adjuvant pemetrexed plus cisplatin for completely resected stage IB to IIIA adenocarcinoma of the lung: APICAL trial.

Background: We aimed to evaluate the efficacy of postoperative adjuvant pemetrexed plus cisplatin (Pem-Cis) in pathologic stage IB-IIIA lung adenocarcinoma (LUAD) patients. Methods: A prospective, phase II study was performed in seven institutions in South Korea. Patients with completely resected stage IB-IIIA LUAD received pemetrexed (500 mg/m2) plus cisplatin (75 mg/m2). Adjuvant treatments were administered every 3 weeks for 4 cycles. The primary endpoint was to prove the Pem-Cis's superiority in terms of 2-year disease-free survival rate (DFSR) compared with historical control without adjuvant chemotherapy (50%). Results: Between August 2015 and February 2018, 105 patients were enrolled in this study. Approximately 31.4% (n=33), 43.8% (n=46), and 24.8% (n=26) of patients had pathologic stage IB, II, and IIIA, respectively. Most of the patients underwent lobectomy (n=98, 93.3%). Moreover, 41.1% and 12.1% of the patients had epidermal growth factor receptor (EGFR) mutation and anaplastic lymphoma kinase rearrangement. Four cycles of Pem-Cis were administered in 99 patients (94.3%). At a median follow-up of 57.7 months, the 2-year DFSR was 78.1%. Multivariable analysis showed that pathologic stage IIIA and EGFR mutation were significant risk factors for DFS. Grade 3 adverse events occurred in 10 patients (9.5%), and leukopenia (n=3, 2.9%) was the most common adverse event. Conclusions: Adjuvant Pem-Cis is superior to historical control without adjuvant treatment in terms of 2-year DFSR; the proportion of patients with stage IB and driver mutations were higher than that of patients in previous trials. Pem-Cis showed favorable tolerability as adjuvant chemotherapy (clinicaltrial.gov; Identifier: NCT02498860).

Early development of pembrolizumab-induced fulminant myositis and cardiotoxicity in a patient with metastatic thymoma.

Herein, we report the case of a 48-year-old woman with metastatic thymoma who developed fulminant myositis with cardiotoxicity after one cycle of pembrolizumab treatment. She presented with severe muscle weakness and dyspnea, and her laboratory test results revealed increased muscle and cardiac enzyme levels. Despite an urgent initiation of systemic steroids, her muscle weakness and hypercapnia worsened, for which intravenous immunoglobulin G was initiated. However, hypercapnia did not improve, but the patient recovered completely after plasma exchange. Patients with thymic neoplasms could be susceptible to fulminant forms of immune-related adverse effects because they lack normal thymic physiology. Clinicians must not hesitate to consider immunoglobulin G administration and plasma exchange therapy as the next treatment steps for steroid-refractory patients.

Cardiac Dysfunction Is Not Associated with Increased Reintubation Rate in Patients Treated with Post-extubation High-Flow Nasal Cannula.

BACKGROUND: Cardiac dysfunction patients have long been considered at high risk of reintubation. However, it is based on past studies in which only conventional oxygen therapy was applied after extubation. We investigated association between cardiac dysfunction and reintubation rate in situation where high-flow nasal cannula (HFNC) was widely used during post-extubation period. METHODS: We conducted a retrospective observational cohort study of patients treated with HFNC after planned extubation in medical intensive care unit of single tertiary center. Patients were divided into normal function group (ejection fraction [EF] ≥45%) and cardiac dysfunction group (EF <45%). The primary outcome was reintubation rate within 72 hours following extubation. RESULTS: Of 270 patients, 35 (13%) had cardiac dysfunction. Baseline characteristics were similar in both groups. There were no differences in the changes in vital signs between the two groups during the first 12 hours after extubation except diastolic blood pressure. The reintubation rates were 20% and 17% for cardiac dysfunction group and normal function group, respectively (p=0.637). In a multivariate Cox regression analysis, cardiac dysfunction was not associated with an increased risk of reintubation within 72 hours following extubation (hazard ratio, 1.56; p=0.292). CONCLUSION: Cardiac dysfunction was not associated with increased reintubation rate within 72 hours when HFNC is immediately applied after planned extubation.

Usefulness of Pulmonary Rehabilitation in Non-Small Cell Lung Cancer Patients Based on Pulmonary Function Tests and Muscle Analysis Using Computed Tomography Images.

PURPOSE: The usefulness of rehabilitation in patients with reduced lung function before lung surgery remains unclear, and there is no adequate method for evaluating the effect of rehabilitation. We aimed to evaluate the usefulness of rehabilitation in patients with non-small cell lung cancer (NSCLC) undergoing lung cancer surgery. MATERIALS AND METHODS: We retrospectively analyzed the medical records of NSCLC patients at Korea University Guro Hospital between 2018 and 2020. Patients were divided into two groups depending on whether they underwent rehabilitation. Pulmonary function test (PFT) data and muscle determined using chest computed tomography (CT) images were analyzed. Because the baseline characteristics were different between the two groups, propensity score matching was performed. RESULTS: Of 325 patients, 75 (23.1%) and 250 (76.9%) were included in the rehabilitation and non-rehabilitation (control) groups, respectively. The rehabilitation group had a worse general condition at baseline. After propensity score matching, 45 patients remained in each group. Pulmonary function (forced expiratory volume in 1 second, %) (p=0.001) and the Hounsfield unit of erector spinae muscle (p=0.001) were better preserved in the rehabilitation group. Muscle loss of 3.4% and 0.6% was observed in the control and rehabilitation groups, respectively (p=0.003). In addition, the incidence of embolic events was lower in the rehabilitation group (p=0.044). CONCLUSION: Pulmonary rehabilitation is useful in patients with NSCLC undergoing lung surgery. Pulmonary rehabilitation preserves lung function, muscle and reduces embolic events after surgery. Pulmonary rehabilitation is recommended for patients with NSCLC undergoing surgery.

Clinical efficacy of adjuvant chemotherapy in stage IB (< 4 cm) non-small cell lung cancer patients with high-risk factors.

BACKGROUND/AIMS: Adjuvant chemotherapy is the standard of care for resected stage II-IIIA non-small cell lung cancer (NCSLC). The efficacy of adjuvant chemotherapy in stage IB (< 4 cm) NSCLC with high-risk factors is controversial. METHODS: This retrospective multicenter study included 285 stage IB NSCLC patients with high-risk factors according to the 8th edition tumor, node, metastasis (TNM) classification from four academic hospitals. High-risk factors included visceral pleural invasion, vascular invasion, lymphatic invasion, lung neuroendocrine tumors, and micropapillary histology patterns. RESULTS: Of the 285 patients, 127 (44.6%) were included in the adjuvant chemotherapy group and 158 (55.4%) were included in the non-adjuvant chemotherapy group. The median follow-up was 41.5 months. Patients in the adjuvant chemotherapy group had a significantly reduced recurrence rate and risk of mortality than those in the non-adjuvant chemotherapy group (hazards ratio, 0.408; 95% confidence interval, 0.221 to 0.754; p = 0.004 and hazards ratio, 0.176; 95% confidence interval, 0.057 to 0.546; p = 0.003, respectively). Adjuvant chemotherapy should be particularly considered for the high-risk factors such as visceral pleural involvement or vascular invasion. Based on the subgroup analysis, adjuvant chemotherapy should be considered when visceral pleural involvement is present, even if the tumor size is < 3 cm. CONCLUSION: Adjuvant chemotherapy may be useful for patients with stage IB NSCLC with high-risk factors and is more relevant for patients with visceral pleural involvement or vascular invasion.

Histone Deacetylase as a Valuable Predictive Biomarker and Therapeutic Target in Immunotherapy for Non-Small Cell Lung Cancer.

PURPOSE: Histone deacetylase inhibitors (HDACis) are epigenetic regulators and used clinically for hematopoietic malignancies. Recently, HDACis have received attention as a factor that modulates the immune system. In this study, the role of histone deacetylase (HDAC) expression as a predictive marker in lung cancer patients who were treated with immune checkpoint inhibitors (ICIs) and the role of HDACi and ICI combination treatment in the mouse tumor model were analyzed. MATERIALS AND METHODS: The overall response rate (ORR) and progression-free survival (PFS) were analyzed by the expression of HDAC. In vitro assay, the mRNA and protein expression levels of cytokines and programmed death-ligand 1 (PD-L1) were analyzed after HDACi treatment. In vivo assay, TC-1 tumor-bearing mice were treated with HDACi and mouse programmed cell death 1 (PD-1) inhibitor. RESULTS: The HDAC6 low expression group showed high ORR and prolonged PFS. When the selective HDAC6 inhibitor was administered to the A549 cell line, the levels of interleukin-1ß and interleukin-6 decreased and the expression of PD-L1 was reduced. Mice that received both the mouse PD-1 inhibitor and pan-HDACi had a smaller tumor size than that of the mice from the control group. Moreover, mice treated with the mouse PD-1 inhibitor and pan-HDACi generated greater numbers of E7-specific CD8+ T cells. CONCLUSION: HDAC6 expression can predict the prognosis of non-small cell lung cancerpatients who were treated with ICIs. Furthermore, co-treatment with HDACi and PD-1 inhibitor was shown to decrease the tumor growth rate and create a favorable tumor microenvironment for cytotoxic T lymphocytes in the TC-1 mouse model.

Prognostic marker for severe acute exacerbation of chronic obstructive pulmonary disease: analysis of diffusing capacity of the lung for carbon monoxide (DLCO) and forced expiratory volume in one second (FEV1).

BACKGROUND: It is important to assess the prognosis of patients with chronic obstructive pulmonary disease (COPD) and acute exacerbation of COPD (AECOPD). Recently, it was suggested that diffusing capacity of the lung for carbon monoxide (DLCO) should be added to multidimensional tools for assessing COPD. This study aimed to compare the DLCO and forced expiratory volume in one second (FEV1) to identify better prognostic factors for admitted patients with AECOPD. METHODS: We retrospectively analyzed 342 patients with AECOPD receiving inpatient treatment. We classified 342 severe AECOPD patients by severity of DLCO and FEV1 (≤ vs. > 50% predicted). We tested the association of FEV1 and DLCO with the following outcomes: in-hospital mortality, need for mechanical ventilation, need for intensive care unit (ICU) care. We analyzed the prognostic factors by multivariate analysis using logistic regression. In addition, we conducted a correlation analysis and receiver operating characteristic (ROC) curve analysis. RESULTS: In multivariate analyses, DLCO was associated with mortality (odds ratio = 4.408; 95% CI 1.070-18.167; P = 0.040) and need for mechanical ventilation (odds ratio = 2.855; 95% CI 1.216-6.704; P = 0.016) and ICU care (odds ratios = 2.685; 95% CI 1.290-5.590; P = 0.008). However, there was no statistically significant difference in mortality rate when using FEV1 classification (P = 0.075). In multivariate linear regression analyses, DLCO (B = - 0.542 ± 0.121, P < 0.001) and FEV1 (B = - 0.106 ± 0.106, P = 0.006) were negatively associated with length of hospital stay. In addition, DLCO showed better predictive ability than FEV1 in ROC curve analysis. The area under the curve (AUC) of DLCO was greater than 0.68 for all prognostic factors, and in contrast, the AUC of FEV1 was less than 0.68. CONCLUSION: DLCO was likely to be as good as or better prognostic marker than FEV1 in severe AECOPD.

Comparison of epidermal growth factor receptor tyrosine kinase inhibitors for patients with lung adenocarcinoma harboring different epidermal growth factor receptor mutation types.

BACKGROUND: Epidermal growth factor receptor (EGFR) mutations in non-small-cell lung cancer predict sensitivity to EGFR tyrosine kinase inhibitors (TKIs). EGFR mutation types are associated with efficacy of EGFR TKIs. We investigated the clinical outcomes of afatinib, erlotinib, and gefitinib according to EGFR mutation type in patients with lung adenocarcinoma. METHODS: Between May 2010 and December 2018, we investigated 363 patients with advanced lung adenocarcinoma harboring EGFR mutations who received EGFR TKIs. Efficacies of EGFR TKIs such as response rate, progression-free survival (PFS), and overall survival (OS) were retrospectively evaluated according to exon 19 deletion (E19del), L858R point mutation (L858R) and uncommon mutations. RESULTS: The frequency of E19del was 48.2%, that of L858R was 42.4%, and that of uncommon mutations was 9.4%. E19del and L858R were associated with superior PFS and OS compared with uncommon mutations. Erlotinib showed significantly inferior OS than other TKIs (30.8 ± 3.3 in erlotinib vs. 39.1 ± 4.3 in afatinib vs. 48.4 ± 6.3 in gefitinib; p = 0.031) in patients with L858R. Gefitinib showed significantly inferior PFS (4.6 ± 1.1 in gefitinib vs. 11.6 ± 2.7 in afatinib vs. 10.6 ± 2.7 in erlotinib; p = 0.049) in patients with uncommon mutations. CONCLUSION: Afatinib was significantly associated with a longer PFS, presenting constant effectiveness in all EGFR mutation types. Caution may be needed on the use of erlotinib for L858R and the use of gefitinib for uncommon EGFR mutations.