Lung Cancer Screening in Asia: An Expert Consensus Report

INTRODUCTION

The incidence and mortality of lung cancer are highest in Asia compared with Europe and USA, with the incidence and mortality rates being 34.4 and 28.1 per 100,000 respectively in East Asia. Diagnosing lung cancer at early stages makes the disease amenable to curative treatment and reduces mortality. In some areas in Asia, limited availability of robust diagnostic tools and treatment modalities, along with variations in specific health care investment and policies, make it necessary to have a more specific approach for screening, early detection, diagnosis, and treatment of patients with lung cancer in Asia compared with the West.

METHOD

A group of 19 advisors across different specialties from 11 Asian countries, met on a virtual Steering Committee meeting, to discuss and recommend the most affordable and accessible lung cancer screening modalities and their implementation, for the Asian population.

RESULTS

Significant risk factors identified for lung cancer in smokers in Asia include age 50 to 75 years and smoking history of more than or equal to 20 pack-years. Family history is the most common risk factor for nonsmokers. Low-dose computed tomography screening is recommended once a year for patients with screening-detected abnormality and persistent exposure to risk factors. However, for high-risk heavy smokers and nonsmokers with risk factors, reassessment scans are recommended at an initial interval of 6 to 12 months with subsequent lengthening of reassessment intervals, and it should be stopped in patients more than 80 years of age or are unable or unwilling to undergo curative treatment.

CONCLUSIONS

Asian countries face several challenges in implementing low-dose computed tomography screening, such as economic limitations, lack of efforts for early detection, and lack of specific government programs. Various strategies are suggested to overcome these challenges in Asia.

Breaking the Invisible Barriers: Unleashing the Full Potential of Immune Checkpoint Inhibitors in Oncogene-Driven Lung Adenocarcinoma

The rapid development of targeted therapy paved the way toward personalized medicine for advanced non-small cell lung cancer (NSCLC). Lung adenocarcinoma (ADC) harboring actionable genetic alternations including epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), Kirsten rat sarcoma virus (ALK) and c-ros oncogene 1 (ROS1) treated with tyrosine kinase inhibitors (TKIs) incurred lesser treatment toxicity but better therapeutic responses compared with systemic chemotherapy. Angiogenesis inhibitors targeting vascular endothelial growth factor (VEGF) have also shown an increase in overall survival (OS) for NSCLC patients. However, acquired resistance to these targeted therapies remains a major obstacle to long-term maintenance treatment for lung ADC patients. The emergence of immune checkpoint inhibitors (ICIs) against programmed cell death protein 1 (PD-1) or programmed cell death-ligand 1 (PD-L1) has changed the treatment paradigm for NSCLC tumors without actionable genetic alternations. Clinical studies have suggested, however, that there are no survival benefits with the combination of targeted therapy and ICIs. In this review, we will summarize and discuss the current knowledge on the tumor immune microenvironment and the dynamics of immune phenotypes, which could be crucial in extending the applicability of ICIs for this subpopulation of lung ADC patients.

Changes in Etiology and Clinical Outcomes of Pleural empyema during the COVID-19 Pandemic

Healthcare-seeking behavior changed during the COVID-19 pandemic and might alter the epidemiology of pleural empyema. In this study, the incidence, etiology and outcomes of patients admitted for pleural empyema in Hong Kong in the pre-COVID-19 (January 2015-December 2019) and post-COVID-19 (January 2020-June 2022) periods were compared. Overall, Streptococcus pneumoniae was the predominant organism in <18-year-old patients, while Streptococcus anginosus, anaerobes and polymicrobial infections were more frequent in adults. In the post-COVID-19 period, a marked decline in the incidence of pleural empyema in children was observed (pre-COVID-19, 18.4 ± 4.8 vs. post-COVID-19, 2.0 ± 2.9 cases per year, p = 0.036), while the incidence in adults remained similar (pre-COVID-19, 189.0 ± 17.2 vs. post-COVID-19, 198.4 ± 5.0 cases per year; p = 0.23). In the post-COVID-19 period, polymicrobial etiology increased (OR 11.37, p < 0.0001), while S. pneumoniae etiology decreased (OR 0.073, p < 0.001). In multivariate analysis, clinical outcomes (length of stay, ICU admission, use of intrapleural fibrinolytic therapy, surgical intervention, death) were not significantly different in pre- and post-COVID-19 periods. In conclusion, an increase in polymicrobial pleural empyema was observed during the pandemic. We postulate that this is related to the delayed presentation of pneumonia to hospitals.

Efficacy of mRNA and Inactivated Whole Virus Vaccines Against COVID-19 in Patients with Chronic Respiratory Diseases

Background

While different COVID-19 vaccines have been developed, there has been lack of data on the efficacy comparison between mRNA and inactivated whole virus vaccine among patients with chronic respiratory diseases, including asthma, chronic obstructive pulmonary disease (COPD), and bronchiectasis.

Methods

This was a retrospective case control study on the efficacy of BNT162b2 (mRNA vaccine) and CoronaVac (inactivated whole virus vaccine) against COVID-19 in patients with chronic respiratory diseases. A total of 327 patients were included, with 109 patients infected with COVID-19 matched with 218 patients without COVID-19. The co-primary outcomes were vaccine effectiveness against symptomatic COVID-19, COVID-19-related hospitalization and COVID-19-related respiratory failure. Vaccine effectiveness was calculated using the formula (1-adjusted odds ratio) x 100.

Results

Patients who received at least 2 doses of CoronaVac had lower risk of being hospitalized for COVID-19 and developing respiratory failure than those who did not have vaccination, with adjusted odds ratio (OR) of 0.189 (95% CI = 0.050-0.714, p = 0.014) and 0.128 (95% CI = 0.026-0.638, p = 0.012) respectively. Patients who received at least 2 doses of BNT162b2 had lower risk of being hospitalized for COVID-19 and developing respiratory failure than those who did not have vaccination with adjusted OR of 0.207 (95% CI = 0.043-0.962, p = 0.050) and 0.093 (95% CI = 0.011-0.827, p = 0.033) respectively. There was no statistically significant difference in the risks of being hospitalized for COVID-19 and developing respiratory failure between patients who received at least 2 doses of CoronaVac or BNT162b2.

Conclusion

BNT162b2 and CoronaVac vaccines are effective in preventing hospitalization for COVID-19 and respiratory failure complicating COVID-19 among patients with chronic respiratory diseases. Patients with chronic respiratory diseases should be encouraged to have COVID-19 vaccination.

Risk of hospitalised bronchiectasis exacerbation based on blood eosinophil counts

SETTING: There has been growing recognition on the importance of phenotyping of airway diseases. The eosinophilic phenotype was proposed in bronchiectasis; however, there has not been any evidence on its association with the risk of hospitalised bronchiectasis exacerbations.OBJECTIVE: To investigate the association between baseline blood eosinophil count (BEC) and bronchiectasis exacerbations requiring hospitalisation with validation by an independent cohort.DESIGN: This was a retrospective cohort study.RESULTS: Over a 24-month period, 37/318 (11.6%) study participants experienced an exacerbation requiring hospitalisation. The mean baseline serum eosinophil was 135 ± 92 cells/µL in those who had exacerbations, and 188 ± 161 cells/µL in those who did not. A serum eosinophil level of 250 cells/µL at stable state was the most significant cut-off for predicting hospitalised bronchiectasis exacerbation, which was validated by the independent cohort.CONCLUSIONS: Patients with BEC below 250 cells/µL at stable state are at increased risk of having hospitalised bronchiectasis exacerbations.

Associations of sleep apnea risk and oxygen desaturation indices with cerebral small vessel disease burden in patients with stroke

Background

Obstructive sleep apnea (OSA) is associated with cerebral small vessel disease (CSVD). Nonetheless, whether OSA-risk determined by a simple screening questionnaire or indices quantifying nocturnal hypoxemia other than the conventional apnea–hypopnea index (AHI) by the home sleep apnea test (HSAT) associated with CSVD burden remains uncertain.

Methods

From 2018 to 2021, we recruited patients with transient ischemic attack (TIA)/minor stroke from the Queen Mary Hospital Acute Stroke Unit and TIA/Stroke Outpatient Clinics. Logistic regression models were applied to determine the association of baseline OSA-risk (on STOP-BANG questionnaire) or HSAT-derived indices quantifying nocturnal hypoxemia with global burden/individual markers of CSVD on MRI. Indices included oxygen desaturation (≥3%) index (ODI), minimum oxygen saturation (SpO₂), percentage of total sleep time with an oxygen saturation <90% (CT90%), and desaturation duration (≥3%, DesDur).

Results

In 283 patients with TIA/minor stroke (mean age 65 years, 64% men), OSA-risk was significantly associated with total CSVD score (multivariate-adjusted odds ratio: 1.23, 95% confidence interval 1.01–1.51), presence of lacunes [1.39 (1.09–1.79)] and burden of basal ganglia PVSs [1.32 (1.06–1.67)]. In 85/283 patients who completed HSAT, neither AHI, minimum SpO₂ nor CT90% was associated with CSVD burden. Nonetheless, ODI and DesDur remained significantly associated with total CSVD score after covariate adjustment: ODI [1.04 (1.01–1.07)] and DesDur [1.04 (1.01–1.08)].

Conclusion

In patients with TIA/minor stroke, high OSA-risk was associated with a greater CSVD burden. Oxygen desaturation indices (ODI and DesDur) rather than AHI were independently associated with global CSVD burden, indicating that longer and more severe desaturations may contribute to the pathogenesis of CSVD.

A Phase IIIb Open-Label, Single-Arm Study of Afatinib in EGFR TKI-Naïve Patients with EGFRm+ NSCLC: Final Analysis, with a Focus on Patients Enrolled at Sites in China

Background

Afatinib has been shown as a suitable option for the treatment of epidermal growth factor receptor mutation-positive (EGFRm+) non-small-cell lung cancer (NSCLC) in randomized controlled trials. However, patients treated in real-world clinical practice, including elderly patients, and those with brain metastases or poor Eastern Cooperative Oncology Group (ECOG) performance statuses, are often excluded from these studies.

Objective

To report the final results, with a particular focus on patients enrolled in China, from a prospective phase IIIb, “near real-world” study of afatinib in tyrosine kinase inhibitor (TKI)-naïve Asian patients with EGFRm+ NSCLC.

Patients and Methods

NCT01953913 was conducted at 34 centers across Asia. Entry criteria were broad to reflect real-world settings. Patients received afatinib 40 mg/day until tumor progression, lack of clinical benefit, or poor tolerability. Assessments included safety, time to symptomatic progression (TTSP), and progression-free survival (PFS).

Results

541 patients were treated, of whom 412 were enrolled in China. Dose reductions were implemented in 28.7% of patients overall, and 17.7% of patients from China. Safety findings were consistent with phase III studies of afatinib. Median TTSP in all patients was 14.0 months (95% CI 12.9–15.9), and median PFS was 12.1 months (95% CI 11.0–13.6). Median TTSP (13.8 months, 95% CI 12.7–16.1) and PFS (11.4 months, 95% CI 10.9–13.7) were similar in patients from China to the overall population. Among patients from China who had dose reductions, TTSP was numerically longer than in those who did not (16.4 vs. 13.8 months; P = 0.0703), while PFS was significantly longer (13.9 vs. 11.1 months; P = 0.0275). Among patients from China with brain metastases, TTSP was numerically shorter than in those without (11.0 vs. 14.4 months; P = 0.0869), whereas PFS was significantly shorter (9.2 vs. 12.9 months; P = 0.0075).

Conclusions

Safety data for afatinib when used in a “near real-world” setting in patients with EGFRm+ NSCLC was consistent with the known safety profile of afatinib. Supporting efficacy data of afatinib were provided in all patients, and in those enrolled in China. Tolerability-guided afatinib dose reduction allowed patients to remain on treatment and continue to experience clinical benefit.

Trial Registration Number and Date of Registration

NCT01953913 (1 October 2013).

Supplementary Information

The online version contains supplementary material available at 10.1007/s11523-021-00859-6.

Nicotinic Acetylcholine Receptor Subunit α7 Mediates Cigarette Smoke-Induced PD-L1 Expression in Human Bronchial Epithelial Cells

Tobacco smoking is the top risk factor for lung cancer development. Nicotine in cigarettes can induce addiction, and its derivatives become potent carcinogens after metabolic activation and activate oncogenic signaling in lung epithelial cells through their expressed nicotinic acetylcholine receptors (nAChRs). However, the effects of smoking on the tumor immune microenvironment are under investigation. In the current study, we investigated whether nicotine activation of nicotinic acetylcholine receptor subunit α7 (nAChRα7, CHRNA7) would induce PD-L1 expression in lung epithelial cells. The expression levels of nAChRα7 and PD-L1 in eight human bronchial epithelial cell (HBEC) lines were measured after treatment with cigarette smoke extract (CSE) or nicotine derivatives. The results showed that PD-L1 expression levels increased in HBECs after exposure to CSE or nicotine derivatives. This induction of PD-L1 expression could be diminished by treatment with CHRNA7 small-interfering RNA, and the relevant signaling was mediated via STAT3 phosphorylation and NRF2 expression. In summary, this study demonstrated that the well-known nicotine derivative-activated nAChRα7 could induce STAT3/NRF2 pathways and subsequently promote PD-L1 expression in normal lung epithelial cells. This information provides mechanistic insight into cigarette smoke-induced immune evasion in lung epithelial cells.

Experience from Asian centers in a named-patient-use program for afatinib in patients with advanced non-small-cell lung cancer who had progressed following prior therapies, including patients with uncommon EGFR mutations

BACKGROUND

This study evaluated outcomes among patients with advanced/metastatic non-small-cell lung cancer (NSCLC) treated at Asian centers participating in the global named-patient-use (NPU) program for afatinib.

METHODS

Patients had progressed after initial benefit with erlotinib or gefitinib, and/or had an EGFR or HER2 mutation, had no other treatment options, and were ineligible for afatinib trials. The recommended starting dose of afatinib was 50 mg/day. Dose modifications were allowed, and afatinib was continued as long as deemed beneficial. Response and survival information was provided voluntarily. Safety reporting was mandatory.

RESULTS

2242 patients (26% aged ≥ 70 years, 96% with adenocarcinoma) received afatinib at centers in 10 Asian countries. Most were heavily pre-treated, including prior treatment with erlotinib or gefitinib. Of 1281 patients tested, 1240 had EGFR mutations (common: 1034/1101; uncommon: 117/1101). There were no new safety signals, the most common adverse events being rash and diarrhea. Objective response rate (ORR) was 24% overall (n = 431 with data available), 27% for patients with common EGFR mutations (n = 230) and 28% for those with uncommon mutations (n = 32); median time to treatment failure (TTF) in these groups was 7.6 months (n = 1550), 6.4 months (n = 692) and 8.4 months (n = 83), respectively. In patients with EGFR exon 20 insertions (n = 23) and HER2 mutations (n = 12), median TTF exceeded 12 months.

CONCLUSIONS

Patient outcomes in this study were similar to those reported in the analysis of the global NPU. Afatinib achieved clinical benefits in patients with refractory NSCLC. ORR and TTF were similar between patients with tumors harboring uncommon and common EGFR mutations.

Continuous positive airway pressure improves blood pressure and serum cardiovascular biomarkers in obstructive sleep apnoea and hypertension

RATIONALE

The impact of treatment for obstructive sleep apnoea (OSA) on reduction of cardiovascular risk is unclear. This study aimed to examine the effect of continuous positive airway pressure (CPAP) on ambulatory blood pressure (BP) and subclinical myocardial injury in subjects with OSA and hypertension.

METHODS

Subjects with hypertension requiring at least three anti-hypertensive medications and moderate-severe OSA were enrolled. Eligible subjects were randomized (1:1) to receive either CPAP treatment or control (no CPAP) for eight weeks. Changes in ambulatory BP and serum biomarkers were compared. Stratified analysis according to circadian BP pattern was performed.

MAIN RESULTS

Ninety two subjects (75% men; age, 51±8 years; apnoea-hypopnoea index 40±8 events·h^-1, taking average of 3.4 anti-hypertensive drugs [range 3-6]) were randomised. The group on CPAP treatment, compared to the control group, demonstrated significant reduction in 24-h systolic BP (-4.4 mmHg, 95% CI -8.7 to -0.1, p=0.046), 24-h diastolic BP (-2.9 mmHg, 95% CI -5.5 to -0.2, p=0.032), daytime systolic BP (-5.4 mmHg, -9.7 to -1.0, p=0.016) and daytime diastolic BP (-3.4 mmHg, 95% CI -6.1 to -0.8, p=0.012). CPAP treatment was associated with significant BP lowering only in non-dippers, but not in dippers. Serum troponin I (mean difference -1.74 pg·mL^-1, 95% CI -2.97 to -0.5, p=0.006) and brain natriuretic peptide (-9.1 pg·mL^-1, 95% CI -17.6 to -0.6, p=0.036) were significantly reduced in CPAP compared to control group.

CONCLUSION

In a cohort with OSA and multiple cardiovascular risk factors including difficult-to-control hypertension, short-term CPAP treatment improved ambulatory BP and alleviated subclinical myocardial injury and strain.

Role of early definitive management for newly diagnosed malignant pleural effusion related to lung cancer

BACKGROUND AND OBJECTIVE

The advent of effective anti-cancer therapy has brought about uncertainty on the benefit of early definitive measures for newly diagnosed MPE from lung cancer. This study aims to investigate the outcomes of MPE in this setting.

METHODS

Lung cancer patients with MPE at first presentation to a tertiary care hospital were followed up till death or censored from 2011 to 2018. Early MPE control measures included chemical pleurodesis or IPC before or shortly after oncological treatment. Predictors of time to MPE re-intervention were identified with Cox proportional hazard analyses.

RESULTS

Of the 509 records screened, 233 subjects were eligible. One hundred and twenty-seven subjects received oral targeted therapy as first-line treatment and 34 (26.8%) underwent early definitive MPE control measures. Early MPE control measures in addition to targeted therapy, as compared to targeted therapy alone, significantly reduced the subsequent need of MPE re-intervention (23.5% vs 53.8%, P = 0.002). Similar benefits from MPE control measures were found in groups receiving systemic anti-cancer therapy or best supportive care (0% vs 52%, P = 0.003; 18% vs 56.7%, P = 0.024, respectively). In the group with targetable mutations, both early MPE control measures (HR: 0.25, 95% CI: 0.12-0.53, P < 0.001) and the use of targeted therapy (HR: 0.22, 95% CI: 0.10-0.46, P < 0.001) were independently associated with longer time to MPE re-interventions.

CONCLUSION

Early MPE control measures in lung cancer has additional benefits on reducing the need and prolonging the time to MPE re-intervention, independent of anti-cancer therapies.

Expression of large tumour suppressor (LATS) kinases modulates chemotherapy response in advanced non-small cell lung cancer

Background

The Hippo signalling pathway plays an important role in regulating organ size and cell proliferation. Down-regulation of large tumour suppressor (LATS) protein homologs LATS1 or LATS2 has been found in lung cancer. LATS1 and LATS2 are the core components of the Hippo signalling pathway. LATS1 and LATS2 share some conserved structural features and exhibit redundant biological functions. The aim of this study was to dissect the interaction between these two homologs.

Methods

In lung adenocarcinoma (AD) cells, protein expression of LATS1 and LATS2 were determined by western blotting; cell viability and apoptosis were measured by MTT and annexin V staining after treatment with cisplatin; subcellular distributions of LATS proteins were determined by immunofluorescence microscopy; LATS2 expression was modulated by shRNA-mediated knockdown or ectopic expression in cancer cell lines.

Results

Manipulation of the expression of these two LATS kinases influenced cisplatin response in advanced lung AD cell lines. High LATS2-to-LATS1 ratio in H2023 cells was associated with cisplatin resistance, while low LATS2-to-LATS1 ratio in CL1-0 and CL83 cells was associated with sensitivity to cisplatin. Manipulating the LATS2-to-LATS1 ratio by LATS2 over-expression in CL1-0 and CL83 rendered them resistant to cisplatin treatment, whereas LATS2 knockdown in H2023 alleviated the LATS2-to-LATS1 ratio and sensitized cancer cells to cisplatin exposure.

Conclusions

Our data suggested that the ratio of expression of LATS kinases played a role in the modulation of cisplatin sensitivity in advanced lung AD, and targeting of LATS proteins as a novel therapeutic strategy for lung AD deserves further investigation.

Satisfaction, preference and error occurrence of three dry powder inhalers as assessed by a cohort naïve to inhaler operation

Background

Inhaled medication is central to the treatment of COPD. Various types of inhaler devices, which directly deliver medication to the lung, have been developed. However, patients often exhibit incorrect techniques of inhaler usage. Effectiveness of therapy may be affected by the ease of device usage, size, convenience of use, durability, clarity of instructions and device preferences of patients. This study compares the satisfaction and preference, as well as error occurrence, with the use of Genuair^®, Ellipta™ and Breezhaler™ by healthy subjects in Hong Kong.

Subjects and methods

One hundred and thirty healthy Hong Kong Chinese subjects aged ≥40 years without a previous diagnosis of COPD and asthma and with no experience of using dry powder inhalers (DPIs) were recruited. Subjects learned to use the three DPIs by initially reading the instructions and then observing a demonstration with verbal explanation. The number of errors committed was evaluated. Subjects also completed a questionnaire to indicate their satisfaction and preference.

Results

The satisfaction score of comfort for Breezhaler was significantly higher than that for Ellipta (p≤0.05), while the satisfaction score on confidence to have inhaled the entire dose was highest for Genuair compared with Ellipta (p≤0.0001) or Breezhaler (p≤0.05). The overall satisfaction score was significantly higher for Genuair than Ellipta (p≤0.05) or Breezhaler (p≤0.01). After reading the instructions, the highest number of subjects committing one or more critical errors was with Breezhaler (97) followed by Genuair (70) and then Ellipta (33). Demonstration reduced the number of critical errors made by subjects for each DPI to one third or lower.

Conclusion

Breezhaler seemed to be more comfortable and easy to carry, but users made less critical errors when using Ellipta after reading the instructions only. Genuair provided the clearest indication of correct dose preparation and inhalation.

CC16 levels correlate with cigarette smoke exposure in bronchial epithelial cells and with lung function decline in smokers

BACKGROUND

Club cell protein-16 (CC16) expression has been associated with smoking-related lung function decline. The study hypothesis was that CC16 expression in both serum and bronchial epithelium is associated with lung function decline in smokers, and exposure to cigarette smoke will lead to reduction in CC16 expression in bronchial epithelial cells.

METHODS

In a cohort of community-based male Chinese subjects recruited for lung function test in 2000, we reassessed their lung function ten years later and measured serum levels of CC16. CC16 expression was further assayed in bronchial epithelium from endobronchial biopsies taken from an independent cohort of subjects undergoing autofluorescence bronchoscopy, and tested for correlation between CC16 immunostaining intensity and lung function. In an in-vitro model, bronchial epithelial cells were exposed to cigarette smoke extract (CSE), and the expression levels of CC16 were measured in bronchial epithelial cells before and after exposure to CSE.

RESULTS

There was a significant association between FEV1 decline and serum CC16 levels in smokers. Expression of CC16 in bronchial epithelium showed significant correlation with FEV1/FVC. Bronchial epithelial cells showed significant decrease in CC16 expression after exposure to CSE, followed by a subsequent rise in CC16 expression upon removal of CSE.

CONCLUSIONS

Results of these clinical and laboratory investigations suggested that low serum CC16 was associated with smoking-related decline in lung function, demonstrated the first time in a Chinese cohort. The data also lend support to the putative role of CC16 in protection against smoking-related bronchial epithelial damage. (Abstract word count: 243) US CLINICAL TRIAL REGISTRY: NCT01185652 , first posted 20 August, 2010.

Nicotinic acetylcholine receptor expression in human airway correlates with lung function

Nicotine and its derivatives, by binding to nicotinic acetylcholine receptors (nAChRs) on bronchial epithelial cells, can regulate cellular signaling and inflammatory processes. Delineation of nAChR subtypes and their responses to nicotine stimulation in bronchial epithelium may provide information for therapeutic targeting in smoking-related inflammation in the airway. Expression of nAChR subunit genes in 60 bronchial epithelial biopsies and immunohistochemical staining for the subcellular locations of nAChR subunit expression were evaluated. Seven human bronchial epithelial cell lines (HBECs) were exposed to nicotine in vitro for their response in nAChR subunit gene expression to nicotine exposure and removal. The relative normalized amount of expression of nAChR α4, α5, and α7 and immunohistochemical staining intensity of nAChR α4, α5, and β3 expression showed significant correlation with lung function parameters. Nicotine stimulation in HBECs resulted in transient increase in the levels of nAChR α5 and α6 but more sustained increase in nAChR α7 expression. nAChR expression in bronchial epithelium was found to correlate with lung function. Nicotine exposure in HBECs resulted in both short and longer term responses in nAChR subunit gene expression. These results gave insight into the potential of targeting nAChRs for therapy in smoking-related inflammation in the airway.

Impact of chronic obstructive pulmonary disease (COPD) in the Asia-Pacific region: the EPIC Asia population-based survey

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a clinical syndrome encompassing a group of chronic, progressive, and debilitating respiratory conditions, that are characterized by incompletely reversible airflow limitation. Within the Asia-Pacific region, prevalence estimates have been derived using various protocols and study methods, and there is little data on the impact of COPD exacerbations. This study aimed to provide a comprehensive picture of the current prevalence and burden of COPD in this region.

METHODS

A population-based survey was conducted in nine Asia-Pacific territories between 01 February 2012 and 16 May 2012. Overall, 112,330 households were screened to identify eligible subjects (aged ≥40 years, with a physician diagnosis of COPD, chronic bronchitis or emphysema, or with identifiable symptoms of chronic bronchitis). Out of a sample of 69,279 individuals aged ≥40 years, 4,289 subjects with COPD were identified. Data were collected via face-to-face interviews or by fixed-line telephone, using a structured questionnaire. A total of 1,841 completed questionnaires were analyzed.

RESULTS

The overall estimated COPD prevalence was 6.2%, with 19.1% of subjects having severe COPD. In the 12 months prior to the survey, nearly half of all subjects (46%) had experienced exacerbations, and 19% had been hospitalized as a result of their condition. When subjects were asked about the impact of their condition on employment, 23% said their condition kept them from working, and 42% felt that their condition limited their ability to work or their activities. Of those who reported taking prescription drugs, 20% did not know the name of the drugs they were taking. Prescription of oral corticosteroids was common, with 44% of subjects having used these during the previous year to manage their respiratory symptoms; in contrast, inhaler use was low (25%). Only 37% of subjects had taken a lung function test, and the majority (89%) of those tested did not know their test results.

CONCLUSIONS

Across the Asia-Pacific territories surveyed, the prevalence of COPD is high, indicating a substantial socioeconomic burden. Our findings suggest that there is considerable room for improvement in the management of COPD, and highlight a need to enhance patient and physician education in the region.

Treatment outcomes in elderly with advanced-stage non-small cell lung cancer

Purpose

Lung cancer remains the top cause of cancer morbidity and mortality in the world. Although the identification of epidermal growth factor receptor (EGFR) gene mutations could predict efficacy of tyrosine kinase inhibitor (TKI), testing for predictive biomarkers are not always possible due to tissue availability. The overall therapeutic decision remains a clinical one for a significant proportion of elderly patients with advanced stage lung cancer but no known EGFR mutation status. The purpose of this study was to compare the outcome of drug treatment modalities in progression-free survival (PFS) and overall survival (OS) for elderly with advanced-stage non-small cell lung cancer (NSCLC) and to identify clinical parameters that could predict treatment outcome.

Methods

Clinical records of patients aged 70 years or older with advanced-stage NSCLC who have received treatment were reviewed. A group of gender- and histology-matched subjects younger than age 70 years were identified as controls.

Results

Fifty-six elderly patients were included. The median age at diagnosis was 73 years; 60.7 % received only one line of treatment. Baseline performance status (PS) was the only predictor of improved PFS (p = 0.042) and OS (p = 0.002). There was no difference in survival between the upfront chemotherapy and the TKI groups

Conclusions

In elderly with advanced-stage NSCLC without known EGFR mutation status, use of EGFR–TKI and chemotherapy resulted in comparable survival benefits. Age was not predictive of worse treatment outcome. The baseline PS should be taken into consideration in the therapeutic decision in elderly with NSCLC where the EGFR mutation status is not known.

Significance of endothelial dysfunction in sleep-related breathing disorder

The endothelium functions not only as a semi-selective barrier between body tissue and circulation; it also plays an active role in the maintenance of a healthy vasculature. Endothelial dysfunction is increasingly found to play a pivotal role in the pathogenesis of atherosclerosis. Impaired endothelium-dependent vasodilation, as a marker of endothelial dysfunction, predates and predicts cardiovascular disease. Endothelial dysfunction is thought to result from oxidative stress, inflammatory gene activation and cytokine cascade, as well as impairment of endothelial repair mechanisms. In the context of sleep-related breathing disorders, obstructive sleep apnoea (OSA) is postulated to contribute independently to cardiovascular morbidity and mortality. Thus, endothelial dysfunction is an important target of research in vascular pathogenesis and also serves as an intermediary outcome indicator in clinical trials evaluating cardiovascular sequelae in OSA. Basic or translational studies have identified cellular and molecular mechanisms of potential relevance to endothelial dysfunction in OSA, while epidemiological or clinical studies have shown endothelial dysfunction attributable to sleep-disordered breathing, which could improve with effective treatment of OSA. Endothelial dysfunction is poised to serve as a call for timely intervention with possibility of halting or even reverting vascular injury in sleep-related breathing disorders. Much remains to be explored about the complex pathways of endothelial dysfunction and its clinical manifestations in subjects with OSA, which are likely to involve multiple contributing factors. Evidence-based information will allow us to construct the framework for guiding individualized clinical management and public health strategies for OSA, as well as cardiometabolic diseases.

Altered profile of circulating endothelial progenitor cells in obstructive sleep apnea

Background

Obstructive sleep apnea (OSA) is independently associated with endothelial dysfunction, which may be perpetuated by alteration in endothelial repair capacity. Our study evaluates changes in endothelial progenitor cell (EPC) profile in relation to OSA and the role of advanced glycation end-products (AGE) in this relationship.

Methods

Consecutive Chinese adults undergoing sleep studies, who had no medical illnesses or regular medications, were enrolled. Subjects with morbid obesity or grossly elevated lipoprotein levels were excluded from analysis. Circulating EPC was measured with flow cytometry analysis.

Results

Seventy-two subjects, 64 % with OSA defined by apnea–hypopnea index (AHI) ≥ 5, were analyzed. CD34+ cell counts were positively correlated with oxygen desaturation index (ODI) (r = 0.250, p = 0.041) and duration of oxygen desaturation <90 % (T90) (r = 0.261, p = 0.033) and negatively with minimal oxygen saturation (r = −0.247, p = 0.044) after adjusting for age, glucose, body weight, and smoking status. AGE was positively correlated with indices of OSA severity (AHI, r = 0.249, p = 0.042; ODI, r = 0.244, p = 0.047; T90, r = 0.243, p = 0.047; minimal oxygen saturation, r = −0.251, p = 0.041) and negatively with CD133+ cells (r = −0.281, p = 0.021). On stepwise multiple linear regression analysis, minimal oxygen saturation (p = 0.013) and CD133+ cell counts (p = 0.029) were found to be significant determinants of AGE level (R² = 0.147).

Conclusions

Nocturnal hypoxemia in OSA subjects was associated with increase in endothelial cells (CD34+) which may promote vascular repair. Accumulation of AGE in OSA may lead to diminution in early EPC (CD133+) and endothelial repair capacity over time, thus contributing to vascular pathogenesis.

C-reactive protein is associated with obstructive sleep apnea independent of visceral obesity

BACKGROUND

Obstructive sleep apnea (OSA) is associated with adverse cardiovascular outcomes. C-reactive protein (CRP) predicts atherosclerotic complications. Our study evaluates whether OSA is associated with an elevated CRP level, after elimination of known confounders including visceral obesity.

METHODS

Men without significant chronic medical illness, regular medications, or illness in the preceding 4 weeks were enrolled. Subjects with morbid obesity, newly detected high BP, or fasting glucose were excluded. They underwent polysomnography and MRI of abdomen to quantify visceral fat volume. High-sensitivity CRP levels were measured.

RESULTS

111 men with mean body mass index (BMI) 26.3 +/- 3.8 kg/m(2) were evaluated. After adjustment for age, smoking, BMI, waist circumference, and sleep efficiency, CRP correlated positively with the apnea-hypopnea index (AHI) [r = 0.35, p < 0.001], duration of O(2) saturation < 90% (r = 0.29, p = 0.002), and arousal index (r = 0.32, p = 0.001), and it correlated negatively with minimal O(2) saturation (r = -0.29, p = 0.002). These correlations were consistent when adjustment was made for MRI visceral fat volume instead of waist circumference. In the regression model, significant predictors of CRP included AHI, waist circumference, and triglycerides (adjusted R(2), 0.33, p = 0.001, p = 0.002, p = 0.018, respectively). Among the 111 subjects, 32 subjects with no or mild OSA (AHI < 15 events/h) were matched with 32 subjects with moderate-to-severe OSA (AHI > or = 15 events/h) in MRI visceral fat volume. CRP was higher in subjects with moderate-to-severe OSA (median, 1.32; 0.45 to 2.34 mg/L) when compared to subjects with no or mild OSA (median, 0.54; 0.25 to 0.89 mg/L; p = 0.001).

CONCLUSIONS

In healthy middle-aged men, elevated CRP level is associated with OSA independent of visceral obesity.

Expression of nicotinic acetylcholine receptor subunit genes in non-small-cell lung cancer reveals differences between smokers and nonsmokers

Nicotine and its derivatives, by binding to nicotinic acetylcholine receptors (nAChR) on bronchial epithelial cells, can regulate cellular proliferation and apoptosis via activating the Akt pathway. Delineation of nAChR subtypes in non-small-cell lung cancers (NSCLC) may provide information for prevention or therapeutic targeting. Expression of nAChR subunit genes in 66 resected primary NSCLCs, 7 histologically non-involved lung tissues, 13 NSCLC cell lines, and 6 human bronchial epithelial cell lines (HBEC) was analyzed with quantitative PCR and microarray analysis. Five nonmalignant HBECs were exposed to nicotine in vitro to study the variation of nAChR subunit gene expression with nicotine exposure and removal. NSCLCs from nonsmokers showed higher expression of nAChR alpha6 (P < 0.001) and beta3 (P = 0.007) subunit genes than those from smokers, adjusted for gender. In addition, nAChR alpha4 (P < 0.001) and beta4 (P = 0.029) subunit gene expression showed significant difference between NSCLCs and normal lung. Using Affymetrix GeneChip U133 Sets, 65 differentially expressed genes associated with NSCLC nonsmoking nAChR alpha6beta3 phenotype were identified, which gave high sensitivity and specificity of prediction. nAChR alpha1, alpha5, and alpha7 showed significant reversible changes in expression levels in HBECs upon nicotine exposure. We conclude that between NSCLCs from smokers and nonsmokers, different nAChR subunit gene expression patterns were found, and a 65-gene expression signature was associated with nonsmoking nAChR alpha6beta3 expression. Finally, nicotine exposure in HBECs resulted in reversible differences in nAChR subunit gene expression. These results further implicate nicotine in bronchial carcinogenesis and suggest targeting nAChRs for prevention and therapy in lung cancer.

Obstructive sleep apnoea in Asia

Obstructive sleep apnoea (OSA) syndrome is the commonest sleep-related breathing disorder worldwide. In Asia, the prevalence of symptomatic OSA in middle-aged men and women is 4.1-7.5% and 2.1-3.2%, respectively. These prevalence rates are similar to those reported in Caucasian populations. Obesity, an established major risk factor for OSA, is less common among Asians, and the reported values of body mass indices (BMIs) of Asians with OSA are lower than in their Caucasian counterparts. However, these population-based studies have consistently demonstrated that obesity is still the major risk factor for OSA in Asians, while other studies have suggested that craniofacial structural factors may make a greater contribution towards development of OSA in Asians than in Caucasians. Sleep medicine is in a developmental stage in many Asian countries, and the condition is likely under-recognised. Although sleep laboratories have been set up in various countries in Asia, the availability of this service is very limited. Continuous positive airway pressure is available in most parts of Asia, but financial constraints may limit its utility. Oral appliances have been postulated to have a greater role in the management of OSA in Asian patients, as they are likely to have more modifiable factors in their craniofacial structures, but this is yet to be proven. There is a great need for research and health care development on sleep disordered breathing in Asia, and the solution will only come with efforts towards promotion of awareness of this condition in both professional and lay communities.

The clinical value of autofluorescence bronchoscopy for the diagnosis of lung cancer

The aim of this study was to evaluate the role of autofluorescence bronchoscopy (AFB) in the routine work-up of lung cancer. Consecutive patients with atypical or suspicious cells in sputum or bronchial aspirate, no localising abnormality on chest radiography and nondiagnostic white-light bronchoscopic (WLB) results were recruited. WLB and AFB were performed sequentially during the same session. All abnormal areas detected by WLB, AFB or both were sampled and the biopsy specimens sent for histological examination. Sixty-two patients were recruited within the 32-month study period. Seventeen had no endobronchial lesion detected. Among the 45 patients with endobronchial lesions, 37 had lesions with a histopathological grade of mild dysplasia or less; of the eight patients who had a lesion with a histological grade of moderate dysplasia or worse, five were found to have lung cancer, two invasive lung cancer and three an intra-epithelial neoplasm (severe dysplasia). Lesions showing moderate dysplasia or worse were more commonly found in patients with suspicious cells than in those with atypical cells on sputum examination. AFB was more sensitive than WLB (91 versus 58%) at detecting these lesions, but less specific (26 versus 50%). A combination of white-light and autofluorescence bronchoscopy can increase the diagnostic yield of this invasive procedure in patients exhibiting abnormal sputum cytology.