Recent advances in diagnostic technologies in lung cancer

The increase in lung cancer incidence of Korea has been dampened since 2000; however, increased human lifespan, interest in health care and the widespread implementation of health examinations have resulted in a considerable rise in detection of small lesions that need to be differentiated from lung cancer. Detection of lung cancer at an early stage rather than at a symptomatic advanced stage is also increasing, suggesting that there are increasing diagnostic demands for small peripheral lung lesions. The development of new molecular diagnostics, including next generation sequencing, companion diagnostics that accompany development of new anti-cancer drugs, and re-biopsy for application of new therapeutic modality accelerate the development of lung cancer diagnostics. In this review, we extensively describe the current available diagnostic tools in lung cancer.ope

Correlation of PD-L1 Expression Tested by 22C3 and SP263 in Non-Small Cell Lung Cancer and Its Prognostic Effect on EGFR Mutation-Positive Lung Adenocarcinoma

BACKGROUND: Programmed death-ligand 1 (PD-L1) expression is tested by immunohistochemistry (IHC)-22C3, SP263, and SP142. The aim of this study is to evaluate the correlation among the three methods of PD-L1 IHC in non-small cell lung cancer (NSCLC) and clinical significance of PD-L1 expression in lung adenocarcinoma with an epidermal growth factor receptor (EGFR)-tyrosine kinase domain mutation. METHODS: The results of 230 patients who were pathologically confirmed as having NSCLC; tested using PD-L1 IHC 22C3, SP263, and SP142 methods; and evaluated via the peptide nucleic acid clamping method to confirm EGFR mutation, were analyzed in this study. RESULTS: 164 patients underwent both the SP263 and 22C3 tests. There was a significant positive correlation between the outcomes of the two tests (Spearman correlation coefficient=0.912, p<0.001), with a derived regression equation as follows: 22C3=15.2+0.884×SP263 (R²=0.792, p<0.001). There was no relationship between the expression of PD-L1 and clinical parameters, including EGFR-tyrosine kinase inhibitor (TKI) mutation. The PD-L1 expression in patients treated with EGFR-TKI yielded a 2-month-shorter progression period than that in the PD-L1-negative group. However, this did not reach statistical significance (PD-L1<1% vs. PD-L1≥1%, 10 months vs. 8 months). CONCLUSION: The results of the 22C3 and those of SP263 methods were in good correlation with one another. Since the PD-L1 expression is not influenced by the EGFR mutation, it is necessary to perform a PD-L1 test to set the treatment direction in the patients with EGFR-mutant NSCLC.ope

Clinical significance of GADD153 expression in stage I non-small cell lung cancer

The transcription factor growth arrest and DNA damage-inducible gene 153 (GADD153), also known as CHOP, is considered to function as a proapoptotic molecule. Overexpression of GADD153 leads to cell cycle arrest and/or apoptosis. However, its clinical implications in non-small cell lung cancer (NSCLC) remain controversial. Therefore, we investigated the expression of GADD153 in stage I NSCLC using immunohistochemistry. Paraffin-embedded tissue sections from 76 patients, who were diagnosed with primary stage I NSCLC and had undergone a curative lung resection, were stained using an anti-GADD153 antibody. The intensity of GADD153 immunostaining was evaluated within the cell membrane and cytoplasm of invasive cancer components. The correlation between the intratumoral expression of GADD153 and various clinical parameters were explored. GADD153 was detected in 29 (38.2%) cases. No statistically significant difference in expression was demonstrated between stage IA and stage IB tumors (35.0 vs. 39.3%; P=0.735). The expression of GADD153 was not affected by histological subtypes or histological grades of differentiation. The intratumoral expression of GADD153 did not influence the overall survival rate (53.29 vs. 52.18 months; P=0.743) or disease-free survival rate (46.97 vs. 54.19 months; P=0.084) of stage I NSCLC patients. However, patients with GADD153 expression demonstrated an improved disease-specific survival rate (28.80 vs. 53.85 months; P=0.020). No patients with GADD153 expression demonstrated distant metastasis (P=0.029). These data suggest that GADD153 expression may be a valuable prognostic factor of early-stage NSCLC in patients who have undergone curative lung resection.ope

Mechanisms of epidermal growth factor receptor tyrosine kinase inhibitor resistance and strategies to overcome resistance in lung adenocarcinoma

Somatic mutations that lead to hyperactivation of epidermal growth factor receptor (EGFR) signaling are detected in approximately 50% of lung adenocarcinoma in people from the Far East population and tyrosine kinase inhibitors are now the standard first line treatment for advanced disease. They have led to a doubling of progression-free survival and an increase in overall survival by more than 2 years. However, emergence of resistant clones has become the primary cause for treatment failure, and has created a new challenge in the daily management of patients with EGFR mutations. Identification of mechanisms leading to inhibitor resistance has led to new therapeutic modalities, some of which have now been adapted for patients with unsuccessful tyrosine kinase inhibitor treatment. In this review, we describe mechanisms of tyrosine kinase inhibitor resistance and the available strategies to overcoming resistance.ope

Presence of mEGFR ctDNA predicts a poor clinical outcome in lung adenocarcinoma

BACKGROUND: Circulating tumor DNA (ctDNA) is a biomarker for the selection of target agents in various malignancies. In this study, we examined the effect of ctDNA presence on the response to EGFR-tyrosine kinase inhibitor (TKI) and on the prognosis in lung adenocarcinoma. METHODS: ctDNA of EGFR-TKI sensitizing mutations (mEGFR), L858R substitution and Exon 19 deletion (E19d) mutation, was evaluated using droplet digital PCR (ddPCR) in 81 patients with lung adenocarcinoma which harbored mEGFR in the corresponding tumor tissues. RESULTS: The study recruited lung cancer patients at various stages, and the sensitivity, specificity, and area under the curve (AUC) of mEGFR ctDNA detection by ddPCR were 40.0%, 88.5%, and 0.68, respectively. It showed higher sensitivity (75.0% vs. 10.0%) and AUC (0.83 vs. 0.49) in the advanced stages of lung adenocarcinoma compared with the early stages and the number of metastases and the fractional abundance of mEGFR ctDNA showed a strong correlation (σ = 0.516; P < 0.001, Spearman correlation test). There was a significantly shorter progression-free survival and duration of disease control by EGFR-TKIs in the ctDNA-positive group than the negative group (14.0 vs. 41.0 months, P = 0.02 and 12.0 vs. 23.0 months, P = 0.02, log-rank test, respectively). There was a trend for overall survival time to be shorter in patients with mEGFR ctDNA than for patients without mEGFR ctDNA (35.6 vs. 67.1 months, P = 0.06, log-rank test). CONCLUSIONS: These data showed that mEGFR ctDNA detection using ddPCR is useful in the advanced stages and its presence predicted distant metastasis and poor clinical outcome in lung adenocarcinoma.ope

부드럽지 않은 영역에서 측정가능한 계수를 가지는 타원형 연립 방정식의 균질화 문제에 대한 W1,p 가늠

학위논문 (박사)-- 서울대학교 대학원 : 수리과학부, 2015. 8. 변순식.In this study, we establish uniform $W^{1,p}$ estimates for weak solutions in homogenization of elliptic systems in divergence-form with measurable coefficients in nonsmooth domains. We consider first an interior regularity and then we study boundary value problems, a Dirichlet problem and a conormal derivative problem. Our main purpose is to find an answer for minimal requirements on the coefficients and the boundary condition of the domains to ensure that Calder\'{o}n-Zygmund theory holds in a homogenization problem.Abstract 1 Introduction 2 Preliminaries 2.1 Notations 2.2 Main assumptions 2.3 Tools 3 Interior estimates 3.1 Main result 3.2 Interior Holder estimates 3.3 Uniform W1,q estimates for homogeneous systems 3.4 Proof of Theorem 3.1.1 4 Dirichlet problems 4.1 Main result 4.2 Boundary Holder estimates and uniform W1,q estimates for homogeneous systems for the flat boundary 4.3 Approximation Lemmas 4.4 Proof of Theorem 4.1.1 5 Conormal derivative problems 5.1 Main result 5.2 Boundary Holder estimates 5.3 Uniform W1,q estimates for homogeneous systems for the flat boundary 5.4 Approximation lemmas 5.5 Proof of Theorem 5.1.1 Abstract (in Korean)Docto

Safety and Effectiveness of Indacaterol in Chronic Obstructive Pulmonary Disease Patients in South Korea

BACKGROUND: Inhaled indacaterol (Onbrez Breezhaler), a long-acting β2-agonist, is approved in over 100 countries, including South Korea, as a once-daily bronchodilator for maintenance and treatment of chronic obstructive pulmonary disease (COPD). Here, we present an interim analysis of a post-marketing surveillance study conducted to evaluate the real-world safety and effectiveness of indacaterol in the Korean population. METHODS: This was an open-label, observational, prospective study in which COPD patients, who were newly prescribed with indacaterol (150 or 300 µg), were evaluated for 12 or 24 weeks. Safety was assessed based on the incidence rates of adverse events (AEs) and serious adverse events (SAEs). Effectiveness was evaluated based on physician's assessment by considering changes in symptoms and lung function, if the values of forced expiratory volume in 1 second were available. RESULTS: Safety data were analyzed in 1,016 patients of the 1,043 enrolled COPD patients receiving indacaterol, and 784 patients were included for the effectiveness analysis. AEs were reported in 228 (22.44%) patients, while 98 (9.65%) patients reported SAEs. The COPD condition improved in 348 patients (44.4%), while the condition was maintained in 396 patients (50.5%), and only 40 patients (5.1%) exhibited worsening of ailment as compared with baseline. During the treatment period, 90 patients were hospitalized while nine patients died. All deaths were assessed to be not related to the study drug by the investigator. CONCLUSION: In real-life clinical practice in South Korea, indacaterol was well tolerated in COPD patients, and can be regarded as an effective option for their maintenance treatment.ope

Lack of Interleukin-10 Expression Could Predict Poor Outcome in Patients with Stage I Non-Small Cell Lung Cancer

PURPOSE: Interleukin-10 (IL-10) may play an important role in controlling tumor growth and metastasis. Some reports have shown that IL-10 can be a potent inhibitor of tumor growth, but others suggest that IL-10 expression by the tumor is an adverse prognostic factor. Because normal bronchial epithelial cells constitutively produce IL-10, we decided to test the prognostic value of IL-10 in a well-defined population of patients with stage I non-small cell lung cancer (NSCLC) treated in a single institution. PATIENTS AND METHODS: Using immunohistochemical analysis, we retrospectively analyzed IL-10 expression in specimens from 138 patients with completely resected clinical/radiographic stage I NSCLC for whom clinical follow-up data were available. RESULTS: IL-10 expression was retained (IL-10 labeling index > or = 10%) in 94 patients (68.1%) and lost in 44 patients (31.9%). The duration of overall, disease-specific, and disease-free survival in the 44 patients lacking IL-10 expression was worse than in the 94 patients with IL-10 expression (P = 0.08, 0.02, and 0.05, respectively; Log-rank test). Interestingly, IL-10 expression was observed more frequently in tumors with squamous cell histology than in tumors of other histological subtypes (P = 0.04; chi(2) test). Multivariate analysis confirmed the independent prognostic value of IL-10 expression for disease-specific survival (P = 0.04). CONCLUSION: Lack of IL-10 expression by the tumor was associated with a significantly worse outcome of early stage NSCLC. The mechanisms underlying this clinically and biologically important finding need to be further explored.ope

Methionyl-tRNA synthetase and aminoacyl-tRNA synthetases interacting multi-functional protein-lacking exon 2 as potential diagnostic biomarkers for lung cancer

Cytological specimens from computed tomography (CT)-guided needle aspiration biopsy (CT-NAB) have relatively low sensitivity for lung cancer diagnosis. This study evaluated the usefulness of the dual immunofluorescence (IF) staining method using methionyl-tRNA synthetase (MARS), aminoacyl-tRNA synthetases interacting multi-functional protein-lacking exon 2 (AIMP2-DX2), and pan-cytokeratin (pan-CK) obtained from clinical specimens. One-hundred forty-five cytology specimens were prospectively collected from patients who underwent CT-NAB under the suspicion of lung cancer. The results of two combinations of MARS, AIMP2-DX2, and pan-CK dual IF staining were compared with those of conventional cytology by calculating the area under the curve (AUC). The results of combining dual IF with conventional cytology showed higher AUC than conventional cytology alone: cytology/MARS/AIMP2-DX2 (0.891 vs. 0.829, P = 0.003), cytology/MARS/pan-CK (0.916 vs. 0.829, P < 0.001), and cytology/AIMP2-DX2/pan-CK (0.877 vs. 0.829, P = 0.005). In specimens with non-diagnostic results in conventional cytology, MARS/AIMP2-DX2 dual IF staining showed sensitivity, specificity, and AUC of 60.0%, 86.4%, and 0.79, respectively. The dual IF staining method using two combinations of MARS, AIMP2-DX2, and pan-CK is an effective diagnostic tool that can improve the lung cancer diagnostic yield by complementing conventional cytology.ope

Lessons learned from continued TB outbreaks in a high school

We investigated the aftereffects of confirmatory QuantiFERON testing (QFT) added to a positive tuberculin skin test (TST). We reviewed the pre and post course of sequential tuberculosis (TB) outbreaks in a high school where massive 43 active TB cases had been found within one year before delayed contact investigation. And we investigated the TB development in relation to initial TST and QFT during mean follow-up of 3.9 ± 0.9 years. After delayed contact investigation for two subsequent TB outbreaks, 925 contacts were divided into the following 3 groups: TST- (n = 632), TST+/QFT+ (n = 24), TST+/QFT- (n = 258). QFT- was more prevalent than QFT+ in contacts with 10mm ≤ TST <15mm (158, 61.2%) compared with TST ≥15mm (100, 38.8%) among the TST+ reactors (P < 0.001). Among the 258 TST+/QFT- subjects, 256 received no latent TB infection (LTBI) treatment, but 7 contacts developed TB during follow-up. Among these 7 patients, 4 had initial TST ≥15mm and 3 had 10mm ≤ TST <15mm. In conclusion, the delayed contact investigation for LTBI in a high school resulted in continued TB developments. False-negative QFT performed late among the TST+ reactors should not be considered criteria for LTBI treatment. Additionally, the contacts only with TST ≥15mm should be considered for LTBI treatment in congregate settings of intermediate-burden countries.ope