Chronic obstructive pulmonary disease is associated with lung cancer mortality in a prospective study of never smokers

Risk stratification by the lower limit of normal of FEV1/FVC for postoperative outcomes in patients with COPD undergoing thoracic surgery

BACKGROUND

Mounting evidence suggests that airway obstruction defined by the lower limit of normal (LLN) of forced expiration volume in 1s (FEV1)/forced vital capacity (FVC) might be an important predictor of mortality in patients with an FEV1/FVC ratio below 0.70. Although better risk stratification for postoperative outcomes in patients with chronic obstructive pulmonary disease (COPD) undergoing thoracic surgery is warranted, whether an FEV1/FVC ratio below 0.70 but above the LLN (i.e., in-between) could identify patients at risk for adverse postoperative outcomes has not been fully evaluated.

METHODS

To determine the clinical impact of this "in-between" group of patients with COPD, we evaluated whether classification of the in-between group and the COPD group with FEV1/FVC ratios below 0.70 and below the LLN could provide more accurate risk stratification for postoperative outcomes in COPD patients undergoing thoracic surgery.

RESULTS

The criterion of LLN classified 302 patients with an FEV1/FVC ratio below 0.70 into either the in-between group (124 cases) or the COPD group (178 cases). The COPD group showed a 3-fold increase in prolonged oxygen therapy (POT) and a 50% increase in prolonged postoperative stay (PPS), as compared with the in-between group, with an adjusted odds ratio of 3.068 (95% confidence interval: 1.806-5.213) for POT.

CONCLUSIONS

Based on the finding that the in-between group could independently identify patients at risk for adverse postoperative outcomes, LLN assessment of the FEV1/FVC ratio might provide more accurate risk stratification in COPD patients undergoing thoracic surgery.

Lung injury and lung cancer caused by cigarette smoke-induced oxidative stress: Molecular mechanisms and therapeutic opportunities involving the ceramide-generating machinery and epidermal growth factor receptor

Chronic obstructive pulmonary disease (COPD) and lung cancer are frequently caused by tobacco smoking. However, these diseases present opposite phenotypes involving redox signaling at the cellular level. While COPD is characterized by excessive airway epithelial cell death and lung injury, lung cancer is caused by uncontrolled epithelial cell proliferation. Notably, epidemiological studies have demonstrated that lung cancer incidence is significantly higher in patients who have preexisting emphysema/lung injury. However, the molecular link and common cell signaling events underlying lung injury diseases and lung cancer are poorly understood. This review focuses on studies of molecular mechanism(s) underlying smoking-related lung injury (COPD) and lung cancer. Specifically, the role of the ceramide-generating machinery during cigarette smoke-induced oxidative stress leading to both apoptosis and proliferation of lung epithelial cells is emphasized. Over recent years, it has been established that ceramide is a sphingolipid playing a major role in lung epithelia structure/function leading to lung injury in chronic pulmonary diseases. However, new and unexpected findings draw attention to its potential role in lung development, cell proliferation, and tumorigenesis. To address this dichotomy in detail, evidence is presented regarding several protein targets, including Src, p38 mitogen-activated protein kinase, and neutral sphingomyelinase 2, the major sphingomyelinase that controls ceramide generation during oxidative stress. Furthermore, their roles are presented not only in apoptosis and lung injury but also in enhancing cell proliferation, lung cancer development, and resistance to epidermal growth factor receptor-targeted therapy for treating lung cancer.

Chronic obstructive pulmonary disease as a risk factor for lung cancer

The association between chronic obstructive pulmonary disease (COPD) and lung cancer has long been a subject of intense debate. The high prevalence of COPD in elderly smokers inevitably strengthens their coincidence. In addition to this contingent coincidence, recent studies have revealed a close association between the two diseases that is independent of the smoking history; that is, the existence of COPD is an independent risk factor for the development of lung cancer. Molecular-based evidence has been accumulating as a result of the efforts to explain the underlying mechanisms of this association. These mechanisms may include the following: the retention of airborne carcinogens followed by the activation of oncogenes and the suppression of tumor suppressor genes; the complex molecular mechanism associated with chronic inflammation in the distal airways of patients with COPD; the possible involvement of putative distal airway stem cells; and genetic factors that are common to both COPD and lung cancer. The existence of COPD in patients with lung cancer may potentially affect the process of diagnosis, surgical resection, radiotherapy, chemotherapy, and end-of-life care. The comprehensive management of COPD is extremely important for the appropriate treatment of lung cancer. Surgical resections with the aid of early interventions for COPD are often possible, even for patients with mild-to-moderate COPD. New challenges, such as lung cancer CT screening for individuals at high risk, are now in the process of being implemented. Evaluating the risk of lung cancer in patients with COPD may be warranted in community-based lung cancer screening.

Detection of chronic obstructive pulmonary disease in community-based annual lung cancer screening: Chiba Chronic Obstructive Pulmonary Disease Lung Cancer Screening Study Group

BACKGROUND AND OBJECTIVE

Detection of chronic obstructive pulmonary disease (COPD) is crucial in the management of COPD. The aim of this study was to establish the utility of a community-based lung cancer screening for detecting COPD.

METHODS

In Japan, community-based lung cancer screening for residents who are 40 years or older using chest radiography is well established. A screening system in Chiba City, Japan, was used to detect COPD. The criteria to consider COPD at screening included age of 60 years or older, a smoking history and chronic respiratory symptoms. Participants fulfilling these criteria were referred for diagnostic evaluation consisting of pulmonary function testing (PFT) and chest computed tomography (CT).

RESULTS

Of 89,100 Chiba City residents who underwent lung cancer screening, 72,653 residents were 60 years or older. Among them, 878 (1.0%) were identified with suspected COPD and referred for further evaluation. Of those identified, a total of 567 residents (64.6%, 567/878) underwent further evaluations, and 161 (28.4%) were reported to have COPD, with 38.5% of them requiring COPD treatment. To verify the diagnoses from the secondary evaluation centres, PFT and CT data were collected from 228 study participants, and 24.9% were diagnosed with COPD. CT findings classified according to the Goddard classification revealed that 20.1% of these participants had moderate to severe emphysema.

CONCLUSIONS

COPD screening added to a community-based lung cancer screening programme may be effective in the detection of patients with COPD.

Olsson A. Is previous respiratory disease a risk factor for lung cancer?

RATIONALE

Previous respiratory diseases have been associated with increased risk of lung cancer. Respiratory conditions often co-occur and few studies have investigated multiple conditions simultaneously.

OBJECTIVES

Investigate lung cancer risk associated with chronic bronchitis, emphysema, tuberculosis, pneumonia, and asthma.

METHODS

The SYNERGY project pooled information on previous respiratory diseases from 12,739 case subjects and 14,945 control subjects from 7 case-control studies conducted in Europe and Canada. Multivariate logistic regression models were used to investigate the relationship between individual diseases adjusting for co-occurring conditions, and patterns of respiratory disease diagnoses and lung cancer. Analyses were stratified by sex, and adjusted for age, center, ever-employed in a high-risk occupation, education, smoking status, cigarette pack-years, and time since quitting smoking.

MEASUREMENTS AND MAIN RESULTS

Chronic bronchitis and emphysema were positively associated with lung cancer, after accounting for other respiratory diseases and smoking (e.g., in men: odds ratio [OR], 1.33; 95% confidence interval [CI], 1.20-1.48 and OR, 1.50; 95% CI, 1.21-1.87, respectively). A positive relationship was observed between lung cancer and pneumonia diagnosed 2 years or less before lung cancer (OR, 3.31; 95% CI, 2.33-4.70 for men), but not longer. Co-occurrence of chronic bronchitis and emphysema and/or pneumonia had a stronger positive association with lung cancer than chronic bronchitis "only." Asthma had an inverse association with lung cancer, the association being stronger with an asthma diagnosis 5 years or more before lung cancer compared with shorter.

CONCLUSIONS

Findings from this large international case-control consortium indicate that after accounting for co-occurring respiratory diseases, chronic bronchitis and emphysema continue to have a positive association with lung cancer.

Prognostic impact of preoperative monocyte counts in patients with resected lung adenocarcinoma

OBJECTIVES

Increasing evidence suggests that an elevated peripheral monocyte count at presentation predicts a poor prognosis in various types of malignancy, including malignant lymphoma. In lung adenocarcinoma, tumor-associated macrophages (TAMs) were reported to be associated with a poor prognosis. However, it is unknown if an elevated peripheral monocyte count is associated with a poor prognosis in lung adenocarcinoma. This study assessed the prognostic impact of the preoperative peripheral monocyte count in lung adenocarcinoma.

MATERIALS AND METHODS

We retrospectively analyzed 302 consecutive patients with lung adenocarcinoma who received curative resection at Kitano Hospital. The receiver operating characteristic (ROC) curve for the peripheral monocyte count was used to determine the cut-off value. The relations between peripheral monocyte counts and clinicopathological factors were assessed. We also evaluated the impacts of possible prognostic factors including the preoperative peripheral monocyte count on survival, using the two-tailed log-rank test and Cox proportional hazards model. In addition, immunohistochemical staining for CD68 was performed to evaluate the monocytes in primary tumors.

RESULTS

A peripheral monocyte count of 430mm(-3) was the optimal cut-off value for prognosis. An elevated peripheral monocyte count was significantly associated with sex, performance status, smoking history, chronic obstructive pulmonary disease and interstitial lung disease. The two-tailed log-rank test demonstrated that patients with an elevated peripheral monocyte count experienced a poorer recurrence-free survival (RFS) and overall survival (OS) (P=0.0063, P<0.0001, respectively). In the multivariate analysis an elevated peripheral monocyte count was shown to be an independent prognostic factor for the RFS and OS (HR: 1.765; 95% CI: 1.071-2.910; P=0.0258, HR: 4.339; 95% CI: 2.032-9.263; P=0.0001, respectively). Furthermore, numbers of the monocytes in primary tumors significantly correlated with peripheral monocyte counts (r=0.627, P<0.0001).

CONCLUSION

The preoperative peripheral monocyte count is an important prognostic factor for patients with lung adenocarcinoma after curative resection.

Surveillance of chronic obstructive pulmonary disease in high-risk individuals by using regional lung cancer mass screening

Background and objective

Patients with chronic obstructive pulmonary disease (COPD) are at risk for lung cancer; the diseases have common etiologies, including cigarette smoking. We aimed to clarify the effectiveness of COPD detection using a regional mass-screening program for lung cancer.

Materials and methods

A total of 7,067 residents of Togane, Chiba, Japan received lung cancer screening between May and July, 2011. We defined four groups of possible COPD candidates: group A (n=358), positive smoking history, positive chronic respiratory symptoms; group B (n=766), positive smoking history, positive lifestyle-related disease; group C (n=75), passive smoking history, positive chronic respiratory symptoms; and group D (n=301), passive smoking history, positive lifestyle-related disease. Candidates underwent on-site pulmonary function testing (PFT).

Results

The criteria for COPD candidates were fulfilled in 1,686 of 7,067 individuals (23.9%); 1,500 participants underwent PFT (89%), and 171 (11.4%) were diagnosed with COPD. The overall COPD detection rate was 2.4%. The frequency of COPD was significantly higher in groups A and B than in groups C and D (P=0.048); however, the distribution of COPD grades was similar among the groups (P=0.372). Multiple logistic regression analysis identified male sex, age 60 years or greater, and positive smoking history as risk factors for COPD.

Conclusion

COPD screening using a community-based lung cancer-screening program may be effective for disease detection. Individuals who are 60 years of age or older with a positive smoking history should undergo PFT to detect COPD.

Correlation of regional emphysema and lung cancer: a lung tissue research consortium-based study

BACKGROUND

Chronic obstructive pulmonary disease and lung cancer are linked because both airflow obstruction and emphysema, on computer tomography, are independent risk factors for lung cancer. However, the local risk of malignancy relative to development of regional emphysema has not yet been defined. Specifically, it is not known if primary lung cancers are associated with regions of worse emphysema within individual patients.

METHODS

We performed a database analysis evaluating the association between the degree of regional emphysema as scored on computer tomography and development of primary lung cancer. We also studied the association between regional emphysema and benign lung nodules. We assembled two distinct cohorts using the National Heart, Lung, and Blood Institute's Lung Tissue Research Consortium database, hypothesizing that lung malignancy will preferentially locate in the regions of the most severe emphysema.

RESULTS

In the Lung Tissue Research Consortium database, 624 cases met criteria for the malignant nodule cohort and 64 were included in the benign nodule cohort. When comparing location of a malignant nodule to other lung regions within the same person, the odds of having a more severe emphysema score in the location of lung cancer was 1.342 (95% confidence interval 1.112-1.620; p = 0.0022). When comparing location of a benign nodule to other lung regions within the same person, the odds of having a more severe emphysema score in the location of the benign nodule was 1.118 (95% confidence interval 0.725-1.725; p = 0.6137).

CONCLUSIONS

Primary lung cancers are associated with areas of worse regional emphysema.

Lung carcinogenesis from chronic obstructive pulmonary disease: characteristics of lung cancer from COPD and contribution of signal transducers and lung stem cells in the inflammatory microenvironment

Chronic obstructive pulmonary disease (COPD) and lung cancer are closely related. The annual incidence of lung cancer arising from COPD has been reported to be 0.8-1.7 %. Treatment of lung cancer from COPD is very difficult due to low cardiopulmonary function, rapid tumor growth, and resistance to molecularly targeted therapies. Chronic inflammation caused by toxic gases can induce COPD and lung cancer. Carcinogenesis in the inflammatory microenvironment occurs during cycles of tissue injury and repair. Cellular damage can induce induction of necrotic cell death and loss of tissue integrity. Quiescent normal stem cells or differentiated progenitor cells are introduced to repair injured tissues. However, inflammatory mediators may promote the growth of bronchioalveolar stem cells, and activation of NF-κB and signal transducer and activator of transcription 3 (STAT3) play crucial roles in the development of lung cancer from COPD. Many of the protumorgenic effects of NF-κB and STAT3 activation in immune cells are mediated through paracrine signaling. NF-κB and STAT3 also contribute to epithelial-mesenchymal transition. To improve lung cancer treatment outcomes, lung cancer from COPD must be overcome. In this article, we review the characteristics of lung cancer from COPD and the mechanisms of carcinogenesis in the inflammatory microenvironment. We also propose the necessity of identifying the mechanisms underlying progression of COPD to lung cancer, and comment on the clinical implications with respect to lung cancer prevention, screening, and therapy.

Clinical impact of prevalence and severity of COPD on the decision-making process for therapeutic management of lung cancer patients

Background

Recent studies suggest that coexistence of chronic obstructive pulmonary disease (COPD) might be independently related to a worse prognosis for lung cancer. However, because data on the substantial prevalence of COPD and its severity in Asian lung cancer patients remain limited, clinical impact of prevalence and severity of COPD among the population has not been fully evaluated. Furthermore, patients with COPD often have comorbidities. Thus, whether the decision-making process for therapeutic management of lung cancer patients might be independently affected by COPD remains elusive.

Methods

Clinical impact of prevalence and severity of COPD were evaluated in 270 Japanese patients with newly diagnosed lung cancer who were sequentially registered and underwent bronchoscopy from August 2010 to July 2012 at Nagoya University hospital. Furthermore, to explore whether or not the severity of airflow obstruction might affect the decision to propose thoracic surgery with curative intent, we evaluated data from patients with lung cancer at stage 1A to 3A who underwent spirometry and bronchoscopy.

Results

The prevalence rate of COPD was 54.4% among Japanese patients with lung cancer who underwent bronchoscopy. The incidence of Global Initiative for Chronic Obstructive Lung Disease (GOLD) grades 1 and 2 was significantly higher than that of GOLD grade 3. Although COPD-related comorbidities were not independent factors for proposing thoracic surgery, the number of thoracic surgeries performed was significantly less in the COPD group than the non-COPD group. Multivariate analysis showed that more severe airway obstruction, advanced clinical staging, and higher age, were independent factors associated with the decision on thoracic surgery.

Conclusions

We demonstrated a high prevalence of COPD among Japanese lung cancer patients. Based on the knowledge that severity of COPD is one of the most important factors in the therapeutic decision, comprehensive assessment of COPD at bronchoscopy might allow us to implement the optimum management for lung cancer patients.

The impact of coexisting COPD on survival of patients with early-stage non-small cell lung cancer undergoing surgical resection

BACKGROUND

COPD is a recognized risk factor for lung cancer, but studies of coexisting COPD in relation to lung cancer outcomes are limited. We assessed the impact of COPD on overall survival (OS) and progression-free survival (PFS) in patients with early-stage non-small cell lung cancer (NSCLC).

METHODS

Patients (N = 902) with early-stage (stage IA-IIB) NSCLC treated with surgical resection were retrospectively analyzed. The association of self-reported, physician-diagnosed COPD with survivals of NSCLC was assessed using the log-rank and Cox regression models, adjusting for age, sex, BMI, smoking, stages, and performance status.

RESULTS

Among this cohort of patients with NSCLC, 330 cases had physician-diagnosed COPD, and 572 did not have COPD. The 5-year OS in patients with COPD (54.4%) was significantly lower (P = .0002) than that in patients without COPD (69.0%). The 5-year PFS rates for patients with COPD and without COPD were 50.1% and 60.6%, respectively (P = .007). Compared with patients without COPD, patients with COPD had increased risk of worse OS (adjusted hazard ratio [HRadj] = 1.41, P = .002) and PFS (HRadj = 1.67, P = .003). The associations between COPD and worse survival outcomes were stronger in men and in squamous cell carcinoma (SCC).

CONCLUSIONS

Coexisting COPD is associated with worse survival outcomes in patients with early-stage NSCLC, particularly for men and for SCC.

Increased risk and related factors of depression among patients with COPD: a population-based cohort study

Background

Depression is a common and mostly undertreated problem in patients with chronic diseases. However, population-based studies on the association between chronic obstructive pulmonary disease (COPD) and subsequent depression are limited in Asian populations. This study evaluated the incidence and risk factors of depression for patients with COPD in Taiwan.

Methods

Using the claims data from the National Health Insurance of Taiwan, we identified 38,010 COPD patients newly diagnosed in 2000–2004 and 38,010 subjects without COPD frequency, matched by sex, age and index date. The incidence rate and hazard ratio for depression were estimated by the end of 2008.

Results

The incidence rate of depression was 1.88 folds higher in the COPD cohort than in the non-COPD cohort (12.2 versus 6.47 per 1,000 person-years, p < 0.0001). The depression risk was the greatest within the first year following COPD diagnosis and tended to decline with follow-up time. Among COPD patients, multivariate analysis showed that younger women and low-income patients were at higher risk of depression. Hospitalization and comorbidities such as hypertension, arthritis, cancer, and heart disease were also significant predictors for depression risk.

Conclusion

This population-based cohort study demonstrated a strong relationship between COPD and subsequent depression. These findings could assist healthcare providers to pinpoint individuals with a higher predisposition to having depression, which could then facilitate the provision of culturally appropriate rehabilitation within the first year after the diagnosis of COPD.

Prevalence of undiagnosed and undertreated chronic obstructive pulmonary disease in lung cancer population

BACKGROUND AND OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is a risk factor and important coexisting disease for lung cancer; however, the current status of management of COPD in lung cancer patients is not fully described. This study addressed this issue in a general teaching hospital in China.

METHODS

Medical records of hospitalized lung cancer patients in Zhongshan Hospital, Fudan University, between January 2006 and December 2010 were reviewed. The definition of COPD was according to the spirometric criteria of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) document. The diagnostic rate (COPD recorded as a discharge diagnosis/spirometry-defined percentage) and conformity to GOLD treatment guidelines were investigated. The factors influencing diagnosis were analysed.

RESULTS

During the study period, the prevalence of spirometry-defined COPD in hospitalized lung cancer patients was 21.6% (705/3263). The overall diagnostic rate of COPD was 7.1%, and the treatment conformity for stable and acute exacerbation of COPD was 27.1% and 46.8%, respectively. Respiratory physicians had a higher diagnostic rate than non-respiratory doctors (34.8% vs 2.9%, P < 0.001) and a better treatment conformity for acute exacerbation of COPD (63.6% vs 37.5%, P = 0.048). Patients with COPD as a discharge diagnosis had more chance to receive guideline-consistent treatment. The diagnostic rate of COPD was higher among patients with a history of smoking, respiratory diseases or symptoms.

CONCLUSIONS

COPD is substantially underdiagnosed and undertreated in a hospitalized lung cancer population. History of smoking, respiratory diseases and symptoms promotes diagnosis. Education of COPD knowledge among patients and doctors is urgently required in this special population.

Smoking and smoking cessation in relation to the development of co-existing non-small cell lung cancer with chronic obstructive pulmonary disease

Previous studies have identified a mixed-phenotype of non-small cell lung cancer (NSCLC) with co-existing chronic obstructive pulmonary disease (COPD). Although NSCLC and COPD share a common risk factor in smoking, whether and how smoking may contribute to the coexistence of NSCLC with COPD (NSCLC-COPD) is unclear. Our study suggests that cigarette smoking is the major risk factor for the development of NSCLC-COPD, especially in females and among patients with squamous cell carcinoma subtype.

Biomarkers in Exhaled Breath Condensate and Serum of Chronic Obstructive Pulmonary Disease and Non-Small-Cell Lung Cancer

Chronic obstructive pulmonary disease (COPD) and lung cancer are leading causes of deaths worldwide which are associated with chronic inflammation and oxidative stress. Lung cancer, in particular, has a very high mortality rate due to the characteristically late diagnosis. As such, identification of novel biomarkers which allow for early diagnosis of these diseases could improve outcome and survival rate. Markers of oxidative stress in exhaled breath condensate (EBC) are examples of potential diagnostic markers for both COPD and non-small-cell lung cancer (NSCLC). They may even be useful in monitoring treatment response. In the serum, S100A8, S100A9, and S100A12 of the S100 proteins are proinflammatory markers. They have been indicated in several inflammatory diseases and cancers including secondary metastasis into the lung. It is highly likely that they not only have the potential to be diagnostic biomarkers for NSCLC but also prognostic indicators and therapeutic targets.

Is it time for a new paradigm for systemic cancer treatment? Lessons from a century of cancer chemotherapy

U.S. SEER (Surveillance Epidemiology and End Results) data for age-adjusted mortality rates for all cancers combined for all races show only a modest overall 13% decline over the past 35 years. Moreover, the greatest contributor to cancer mortality is treatment-resistant metastatic disease. The accepted therapeutic paradigm for the past half-century for the treatment of advanced cancers has involved the use of systemic chemotherapy drugs cytotoxic for cycling cells (both normal and malignant) during DNA synthesis and/or mitosis. The failure of this therapeutic modality to achieve high-level, consistent rates of disease-free survival for some of the most common cancers, including tumors of the lung, colon breast, brain, melanoma, and others is the focus of this paper. A retrospective assessment of critical milestones in cancer chemotherapy indicates that most successful therapeutic regimens use cytotoxic cell cycle inhibitors in combined, maximum tolerated, dose-dense acute treatment regimens originally developed to treat acute lymphoblastic leukemia and some lymphomas. Early clinical successes in this area led to their wholesale application to the treatment of solid tumor malignancies that, unfortunately, has not produced consistent, long-term high cure rates for many common cancers. Important differences in therapeutic sensitivity of leukemias/lymphomas versus solid tumors can be explained by key biological differences that define the treatment-resistant solid tumor phenotype. A review of these clinical outcome data in the context of recent developments in our understanding of drug resistance mechanisms characteristic of solid tumors suggests the need for a new paradigm for the treatment of chemotherapy-resistant cancers. In contrast to reductionist approaches, the systemic approach targets both microenvironmental and systemic factors that drive and sustain tumor progression. These systemic factors include dysregulated inflammatory and oxidation pathways shown to be directly implicated in the development and maintenance of the cancer phenotype. The paradigm stresses the importance of a combined preventive/therapeutic approach involving adjuvant chemotherapies that incorporate anti-inflammatory and anti-oxidant therapeutics.

Chronic obstructive pulmonary disease and risk of lung cancer: the importance of smoking and timing of diagnosis

INTRODUCTION

The majority of cases of both lung cancer and chronic obstructive pulmonary disease (COPD) are attributable to cigarette smoking, but whether COPD is an independent risk factor for lung cancer remains unclear.

METHODS

We used The Health Improvement Network, a U.K. general practice database, to identify incident cases of lung cancer and controls matched on age, sex, and practice. Using conditional logistic regression, we assessed the effects of timing of first diagnoses of COPD, pneumonia, and asthma on the odds of lung cancer, adjusting for smoking habit.

RESULTS

Of 11,888 incident cases of lung cancer, 23% had a prior diagnosis of COPD compared with only 6% of the 37,605 controls. The odds of lung cancer in patients who had COPD diagnosed within 6 months of their cancer diagnosis were 11-fold those of patients without COPD (odds ratio 11.47, 95% confidence interval 9.38-14.02). However, when restricted to earlier COPD diagnoses, with adjustment for smoking, the effect markedly diminished (for COPD diagnoses >10 years before lung cancer diagnosis, odds ratio: 2.18, 95% confidence interval: 1.87-2.54). The pattern was similar for pneumonia. The effect of COPD on lung cancer remained after excluding patients who had a codiagnosis of asthma.

CONCLUSION

A diagnosis of COPD is strongly associated with a diagnosis of lung cancer, however, this association is largely explained by smoking habit, strongly dependent on the timing of COPD diagnosis, and not specific to COPD. It seems unlikely, therefore, that COPD is an independent risk factor for lung cancer.

Chronic obstructive pulmonary disease and comorbidities

Results of epidemiological studies have shown that chronic obstructive pulmonary disease (COPD) is frequently associated with comorbidities, the most serious and prevalent being cardiovascular disease, lung cancer, osteoporosis, muscle weakness, and cachexia. Mechanistically, environmental risk factors such as smoking, unhealthy diet, exacerbations, and physical inactivity or inherent factors such as genetic background and ageing contribute to this association. No convincing evidence has been provided to suggest that treatment of COPD would reduce comorbidities, although some indirect indications are available. Clear evidence that treatment of comorbidities improves COPD is also lacking, although observational studies would suggest such an effect for statins, β blockers, and angiotensin-converting enzyme blockers and receptor antagonists. Large-scale prospective studies are needed. Reduction of common risk factors seems to be the most powerful approach to reduce comorbidities. Whether reduction of so-called spill-over of local inflammation from the lungs or systemic inflammation with inhaled or systemic anti-inflammatory drugs, respectively, would also reduce COPD-related comorbidities is doubtful.

Lung carcinogenesis by tobacco smoke

Cigarette smoke is a complex mixture of chemicals including multiple genotoxic lung carcinogens. The classic mechanisms of carcinogen metabolic activation to DNA adducts, leading to miscoding and mutations in critical growth control genes, applies to this mixture but some aspects are difficult to establish because of the complexity of the exposure. This article discusses certain features of this mechanism including the role of nicotine and its receptors; lung carcinogens, co-carcinogens and related substances in cigarette smoke; structurally characterized DNA adducts in the lungs of smokers; the mutational consequences of DNA adduct formation in smokers' lungs; and biomarkers of nicotine and carcinogen uptake as related to lung cancer. While there are still uncertainties which may never be fully resolved, the general mechanisms by which cigarette smoking causes lung cancer are well understood and provide insights relevant to prevention of lung cancer, the number one cancer killer in the world, causing 1.37 million deaths per year.

Long-term safety study of infliximab in moderate-to-severe chronic obstructive pulmonary disease

RATIONALE

There was an increased number of malignancies in infliximab-treated (5.7%) over placebo-treated (1.3%) patients in a 44-week, phase 2 clinical study of 234 patients with moderate-to-severe chronic obstructive pulmonary disease (COPD).

OBJECTIVES

To collect malignancy and mortality data from completed clinical studies of infliximab in COPD treatment.

METHODS

The multicenter, observational Remicade Safety Under Long-Term Study in COPD (RESULTS COPD) collected malignancy and mortality data every six months for five years from patients who received ≥1 study-agent dose in a phase 2 study. Co-primary endpoints were the number of patients with malignancy and the number of deaths. Secondary endpoints included the number of patients with a malignancy according to malignancy type.

RESULTS

There was a gap period between the end of the phase 2 study and the initiation of RESULTS COPD, during which six malignancies and 14 deaths were reported spontaneously for the 107 (45.7%) of 234 patients with long-term safety information. Twenty-eight patients (overall 12.0%; placebo 10.4%, infliximab 12.7%) reported malignancies, including 12 patients during RESULTS COPD. Twenty-six patients (overall 11.1%; placebo 9.1%, infliximab 12.1%) died, including nine during RESULTS COPD. Lung cancer was the most common malignancy type (placebo n = 2; infliximab n = 10).

CONCLUSIONS

The greater proportion of malignancies observed with infliximab versus placebo in a phase 2 study diminished over the long-term follow-up. Due to the observational nature, limited patient participation, potential reporting bias from the interim spontaneous reporting period, and unblinding of all patients, more definitive conclusions cannot be drawn.

Overwhelming support among urban Irish COPD patients for lung cancer screening by low-dose CT scan

PURPOSE

The National Lung Screening Trial (NLST) has renewed interest in low-dose computed tomography (LDCT) screening for lung cancer. Smokers may be less receptive toward LDCT screening, however, compared with never smokers. The views of patients with COPD, a particularly high-risk group, toward LDCT screening for lung cancer are currently unknown. We therefore evaluated attitudes of patients with COPD toward LDCT screening for lung cancer.

METHODS

Interviews with Irish patients with COPD who satisfied NLST eligibility criteria were conducted in clinical settings using a questionnaire based on that of a comparable study of U.S. current/former smokers of unspecified disease status.

RESULTS

A total of 142 subjects had a mean age of 65.09 ± 6.07 years (46.4 % were male, mean pack years 54.5 ± 33.3, mean FEV1 59.16 ± 23 %); 97.8 % had an identifiable usual source of healthcare. Compared with data from a U.S. cohort of current/former smokers, a higher proportion of Irish COPD smokers: believed that they were at risk for lung cancer (63.6 vs. 15.7 %); believed that early detection improved chances of survival (90 vs. 51.2 ); were willing to consider LDCT screening (97.9 vs. 78.6 %); were willing to pay for a LDCT scan (68.6 vs. 36.2 %); and were willing to accept treatment recommendations arising (95.7 vs. 56.2 %; p < 0.0001 for all comparisons).

CONCLUSIONS

Urban Irish smokers with COPD who would be eligible for LDCT screening are almost universally in favor of being screened and treated for screening-detected lung cancers. This readily accessible high-risk population should be actively targeted in future screening programs.

Association between chronic obstructive pulmonary disease and lung cancer: a case-control study in Southern Chinese and a meta-analysis

Background

Lung cancer and chronic obstructive pulmonary disease (COPD) share a common risk factor in cigarette smoking and a large portion of patients with lung cancer suffer from COPD synchronously. We therefore hypothesized that COPD is an independent risk factor for lung cancer. Our aim was to investigate the intrinsic linkage of COPD (or emphysema, chronic bronchitis and asthma) and lung cancer.

Methods

The present hospital-based case-control study included 1,069 patients with newly diagnosed lung cancer and 1,132 age frequency matched cancer-free controls. The odds ratios (ORs) for the associations between each previous pulmonary disease and lung cancer were estimated with logistic regression models, adjusting for age, sex, family history of cancer, BMI and pack year smoking. In meta-analysis, the pooled effects of previous pulmonary diseases were analyzed with random effects models; and stratification analyses were conducted on smoking status and ethnicity.

Results

In the case-control study, previous COPD was associated with the odds for increased risk of lung cancer (OR = 1.29, 95% confidence interval [CI] = 1.00∼1.68); so were emphysema (OR = 1.55, 95%CI = 1.03∼2.32) and chronic bronchitis (OR = 1.22, 95%CI = 0.99∼1.67); while asthma was associated with odds for decreased risk of lung cancer (OR = 0.29, 95%CI = 0.16∼0.53). These associations were more pronounced in smokers (P<.05 for all strata), but not in non-smokers. In meta-analysis, 35 studies (22,010 cases and 44,438 controls) were identified. COPD was significantly associated with the odds for increased risk of lung cancer (pooled OR = 2.76; 95% CI = 1.85–4.11), so were emphysema (OR = 3.02; 95% CI = 2.41–3.79) and chronic bronchitis (OR = 1.88; 95% CI = 1.49–2.36); and these associations were more pronounced in smokers than in non-smokers (P<.001 respectively). No significant association was observed for asthma.

Conclusion

Previous COPD could increase the risk of lung cancer, especially in smokers.

Long-term survival in patients hospitalized for chronic obstructive pulmonary disease: a prospective observational study in the Nordic countries

Background and aim

Mortality rate is high in patients with chronic obstructive pulmonary disease (COPD). Our aim was to investigate long-term mortality and associated risk factors in COPD patients previously hospitalized for a COPD exacerbation.

Methods

A total of 256 patients from the Nordic countries were followed for 8.7 ± 0.4 years after the index hospitalization in 2000–2001. Prior to discharge, the St George’s Respiratory Questionnaire was administered and data on therapy and comorbidities were obtained. Information on long-term mortality was obtained from national registries in each of the Nordic countries.

Results

In total, 202 patients (79%) died during the follow up period, whereas 54 (21%) were still alive. Primary cause of death was respiratory (n = 116), cardiovascular (n = 43), malignancy (n = 28), other (n = 10), or unknown (n = 5). Mortality was related to older age, with a hazard risk ratio (HRR) of 1.75 per 10 years, lower forced expiratory volume in 1 second (FEV₁) (HRR 0.80), body mass index (BMI) <20 kg/m² (HRR 3.21), and diabetes (HRR 3.02). Older age, lower BMI, and diabetes were related to both respiratory and cardiovascular mortality. An association was also found between lower FEV₁ and respiratory mortality, whereas mortality was not significantly associated with therapy, anxiety, or depression.

Conclusion

Almost four out of five patients died within 9 years following an admission for COPD exacerbation. Increased mortality was associated with older age, lower lung function, low BMI, and diabetes, and these factors should be taken into account when making clinical decisions about patients who have been admitted to hospital for a COPD exacerbation.

Genetic epidemiology of cigarette smoke-induced lung disease

Chronic obstructive pulmonary disease (COPD) and lung cancer represent two diseases that share a strong risk factor in smoking, and COPD increases risk of lung cancer even after adjusting for the effects of smoking. These diseases not only occur jointly within an individual but also there is evidence of shared occurrence within families. Understanding the genetic contributions to these diseases, both individually and jointly, is needed to identify the highest risk group for screening and targeted prevention, as well as aiding in the development of targeted treatments. The chromosomal regions that have been identified as being associated either jointly or independently with lung cancer, COPD, nicotine addiction, and lung function are presented. Studies jointly measuring genetic variation in lung cancer and COPD have been limited by the lack of detailed COPD diagnosis and severity data in lung cancer populations, the lack of lung cancer-specific phenotypes (histology and tumor markers) in COPD populations, and the lack of inclusion of minorities. African Americans, who smoke fewer cigarettes per day and have different linkage disequilibrium and disease patterns than whites, and Asians, also with different patterns of exposure to lung carcinogens and linkage patterns, will provide invaluable information to better understand shared and independent genetic contributions to lung cancer and COPD to more fully define the highest risk group of individuals who will most benefit from screening and to develop molecular signatures to aid in targeted treatment and prevention efforts.

Role of mtDNA haplogroups in COPD susceptibility in a southwestern Han Chinese population

The interplay of a complex genetic basis with the environmental factors of chronic obstructive pulmonary disease (COPD) may account for the differences in individual susceptibility to COPD. Mitochondrial DNA (mtDNA) contributes to an individual's ability to resist oxidation, an important determinant that affects COPD susceptibility. To investigate whether mtDNA haplogroups play important roles in COPD susceptibility, the frequencies of mtDNA haplogroups and an 822-bp mtDNA deletion in 671 COPD patients and 724 control individuals from southwestern China were compared. Multivariate logistic regression analysis revealed that, whereas mtDNA haplogroups A and M7 might be associated with an increased risk for COPD (OR=1.996, 95% CI=1.149-2.831, p=0.006, and OR=1.754, 95% CI=1.931-2.552, p=0.021, respectively), haplogroups F, D, and M9 might be associated with a decreased risk for COPD in this population (OR=0.554, 95% CI=0.390-0.787, p=0.001; OR=0.758, 95% CI=0.407-0.965, p=0.002; and OR=0.186, 95% CI=0.039-0.881, p=0.034, respectively). Additionally, the increased frequency of the 822-bp mtDNA deletion in male cigarette-smoking subjects among COPD patients and controls of haplogroup D indicated that haplogroup D might increase an individual's susceptibility to DNA damage from external reactive oxygen species derived from heavy cigarette smoking. We conclude that haplogroups A and M7 might be risk factors for COPD, whereas haplogroups D, F, and M9 might decrease the COPD risk in this Han Chinese population.

Reconsidering sex-based stereotypes of COPD

Chronic obstructive pulmonary disease (COPD) has historically been considered a disease of older, white, male smokers, as illustrated in Frank Netter's classic images of the 'pink puffer' and 'blue bloater'. However, women may be more susceptible to COPD than men, and the disease course may be reflective of that increased susceptibility. From a review of epidemiological data of COPD, we found differences in the way men and women present with COPD symptoms, a bias in the way COPD symptoms are treated in men and women, and differences in susceptibility to airway obstruction based on age, sex, and smoking history. These data show that classic stereotypes of COPD - including male predominance - should be abandoned, and that there are not two but multiple COPD phenotypes, which are characterised by differences between women and men in susceptibility, symptoms, and disease progression. These differences impact on physician perception. Although further research into this concept is needed, the differences we found should prompt, in the short term, changes in the way (and in whom) COPD is evaluated, diagnosed, and treated; in the long term, these differences should prompt research into the prognosis of COPD based on sex differences.

Comorbidities and risk of mortality in patients with chronic obstructive pulmonary disease

RATIONALE

Patients with chronic obstructive pulmonary disease (COPD) are afflicted by comorbidities. Few studies have prospectively evaluated COPD comorbidities and mortality risk.

OBJECTIVES

To prospectively evaluate COPD comorbidities and mortality risk.

METHODS

We followed 1,664 patients with COPD in five centers for a median of 51 months. Systematically, 79 comorbidities were recorded. We calculated mortality risk using Cox proportional hazard, and developed a graphic representation of the prevalence and strength of association to mortality in the form of a "comorbidome". A COPD comorbidity index (COPD specific comorbidity test [COTE]) was constructed based on the comorbidities that increase mortality risk using a multivariate analysis. We tested the COTE index as predictor of mortality and explored whether the COTE index added predictive information when used with the validated BODE index.

MEASUREMENTS AND MAIN RESULTS

Fifteen of 79 comorbidities differed in prevalence between survivors and nonsurvivors. Of those, 12 predicted mortality and were integrated into the COTE index. Increases in the COTE index were associated with an increased risk of death from COPD-related (hazard ratio [HR], 1.13; 95% confidence interval, 1.08-1.18; P < 0.001) and non-COPD-related causes (HR, 1.18; 95% confidence interval, 1.15-1.21; P < 0.001). Further, increases in the BODE and COTE were independently associated with increased risk of death. A COTE score of greater than or equal to 4 points increased by 2.2-fold the risk of death (HR, 2.26-2.68; P < 0.001) in all BODE quartile.

CONCLUSIONS

Comorbidities are frequent in COPD and 12 of them negatively influence survival. A simple disease-specific comorbidities index (COTE) helps assess mortality risk in patients with COPD.

Lung cancer screening: a review of available data and current guidelines

Lung cancer is the leading cause of cancer mortality worldwide. A lack of clinical symptoms in early-stage disease frequently leads to diagnosis at a late stage, and a 15% 5-year survival rate in all patients so diagnosed. This has led to significant interest in effective screening methods to detect early-stage cancers, particularly for high-risk groups, such as current or former smokers. Early clinical trials focused on chest radiograph with or without sputum cytology and failed to show an improvement in mortality with screening. A meta-analysis also failed to show a difference in all-cause mortality. Subsequent protocols compared low-dose computed tomography (LDCT) scan with chest radiograph and documented increased detection of early-stage disease; however, they were not designed to prove a reduction in mortality. The most recent trials have focused on LDCT scans, including the National Lung Screening Trial. Data released from the National Lung Screening Trial demonstrated a statistically significant reduction in lung cancer deaths in patients screened with LDCT scans. When data from the study, including cost-effectiveness, are completely analyzed, they may lead to revision of current lung cancer screening recommendations to include LDCT scans in specific populations at high risk of developing lung cancer.

Enhancement of lung tumorigenesis in a Gprc5a Knockout mouse by chronic extrinsic airway inflammation

Background

Although cigarette smoking is the principal cause of lung carcinogenesis, chronic obstructive pulmonary disease (COPD), an inflammatory disease of the lung, has been identified as an independent risk factor for lung cancer. Bacterial colonization, particularly with non-typeable Haemophilus influenzae (NTHi), has been implicated as a cause of airway inflammation in COPD besides cigarette smoke. Accordingly, we hypothesized that lung cancer promotion may occur in a chronic inflammatory environment in the absence of concurrent carcinogen exposure.

Results

Herein, we investigated the effects of bacterial-induced COPD-like inflammation and tobacco carcinogen-enhanced tumorigenesis/inflammation in the retinoic acid inducible G protein coupled receptor knock out mouse model (Gprc5a-/- mouse) characterized by late-onset, low multiplicity tumor formation. Three-month-old Gprc5a-/- mice received 4 intraperitoneal injections of the tobacco-specific carcinogen, NNK, followed by weekly exposure to aerosolized NTHi lysate for 6 months. The numbers of inflammatory cells in the lungs and levels of several inflammatory mediators were increased in Gprc5a-/- mice treated with NTHi alone, and even more so in mice pretreated with NNK followed by NTHi. The incidence of spontaneous lung lesions in the Gprc5a-/- mice was low, but NTHi exposure led to enhanced development of hyperplastic lesions. Gprc5a-/- mice exposed to NNK alone developed multiple lung tumors, while NTHi exposure increased the number of hyperplastic foci 6-fold and the tumor multiplicity 2-fold. This was associated with increased microvessel density and HIF-1α expression.

Conclusion

We conclude that chronic extrinsic lung inflammation induced by bacteria alone or in combination with NNK enhances lung tumorigenesis in Gprc5a-/- mice.

Lung cancer: epidemiology, etiology, and prevention

Lung cancer is the leading cause of cancer death in the United States and around the world. A vast majority of lung cancer deaths are attributable to cigarette smoking, and curbing the rates of cigarette smoking is imperative. Understanding the epidemiology and causal factors of lung cancer can provide additional foundation for disease prevention. This article focuses on modifiable risk factors, including tobacco smoking, occupational carcinogens, diet, and ionizing radiation. It also discusses briefly the molecular and genetic aspects of lung carcinogenesis.

Lung cancer: epidemiology, etiology, and prevention

Lung cancer is the leading cause of cancer death in the United States and around the world. A vast majority of lung cancer deaths are attributable to cigarette smoking, and curbing the rates of cigarette smoking is imperative. Understanding the epidemiology and causal factors of lung cancer can provide additional foundation for disease prevention. This article focuses on modifiable risk factors, including tobacco smoking, occupational carcinogens, diet, and ionizing radiation. It also discusses briefly the molecular and genetic aspects of lung carcinogenesis.

Robust, standardized quantification of pulmonary emphysema in low dose CT exams

RATIONALE AND OBJECTIVES

The aim of this study was to present and evaluate a fully automated system for emphysema quantification on low-dose computed tomographic images. The platform standardizes emphysema measurements against changes in the reconstruction algorithm and slice thickness.

MATERIALS AND METHODS

Emphysema was quantified in 149 patients using a fully automatic, in-house developed software (the Robust Automatic On-Line Pulmonary Helper). The accuracy of the system was evaluated against commercial software, and its reproducibility was assessed using pairs of volume-corrected images taken 1 year apart. Furthermore, to standardize quantifications, the effect of changing the reconstruction parameters was modeled using a nonlinear fit, and the inverse of the model function was then applied to the data. The association between quantifications and pulmonary function testing was also evaluated. The accuracy of the in-house software compared to that of commercial software was measured using Spearman's rank correlation coefficient, the mean difference, and the intrasubject variability. Agreement between the methods was studied using Bland-Altman plots. To assess the reproducibility of the method, intraclass correlation coefficients and Bland-Altman plots were used. The statistical significance of the differences between the standardized data and the reference data (soft-tissue reconstruction algorithm B40f; slice thickness, 1 mm) was assessed using a paired two-sample t test.

RESULTS

The accuracy of the method, measured as intrasubject variability, was 3.86 mL for pulmonary volume, 0.01% for emphysema index, and 0.39 Hounsfield units for mean lung density. Reproducibility, assessed using the intraclass correlation coefficient, was >0.95 for all measurements. The standardization method applied to compensate for variations in the reconstruction algorithm and slice thickness increased the intraclass correlation coefficients from 0.87 to 0.97 and from 0.99 to 1.00, respectively. The correlation of the standardized measurements with pulmonary function testing parameters was similar to that of the reference (for the emphysema index and the obstructive subgroup: forced expiratory volume in 1 second, -0.647% vs -0.615%; forced expiratory volume in 1 second/forced vital capacity, -0.672% vs -0.654%; and diffusing capacity for carbon monoxide adjusted for hemoglobin concentration, -0.438% vs -0.523%).

CONCLUSIONS

The new emphysema quantification method presented in this report is accurate and reproducible and, thanks to its standardization method, robust to changes in the reconstruction parameters.

Radon and COPD mortality in the American Cancer Society Cohort

Although radon gas is a known cause of lung cancer, the association between residential radon and mortality from non-malignant respiratory disease has not been well characterised. The Cancer Prevention Study-II is a large prospective cohort study of nearly 1.2 million Americans recruited in 1982. Mean county-level residential radon concentrations were linked to study participants' residential address based on their ZIP code at enrolment (mean ± SD 53.5 ± 38.0 Bq · m(-3)). Cox proportional hazards regression models were used to estimate adjusted hazard ratios (HR) and 95% confidence intervals (CI) for non-malignant respiratory disease mortality associated with radon concentrations. After necessary exclusions, a total of 811,961 participants in 2,754 counties were included in the analysis. Throughout 2006, there were a total of 28,300 non-malignant respiratory disease deaths. Radon was significantly associated with chronic obstructive pulmonary disease (COPD) mortality (HR per 100 Bq · m(-3) 1.13, 95% CI 1.05-1.21). There was a significant positive linear trend in COPD mortality with increasing categories of radon concentrations (p<0.05). Findings suggest residential radon may increase COPD mortality. Further research is needed to confirm this finding and to better understand possible complex inter-relationships between radon, COPD and lung cancer.

Myocardial infarction and other co-morbidities in patients with chronic obstructive pulmonary disease: a Danish nationwide study of 7.4 million individuals

AIMS

Myocardial infarction is nominally the most important co-morbidity in patients with chronic obstructive pulmonary disease, and the one with the greatest potential for treatment and prevention to improve the overall prognosis of chronic obstructive pulmonary disease patients. We assessed the extent of myocardial infarction and other co-morbidities in individuals with chronic obstructive pulmonary disease in the general population.

METHODS AND RESULTS

We used individual participant data for the entire Danish population from 1980 through 2006, comprising 140 million person-years of follow-up. We used information from four national Danish registries with 100% follow-up and detected ever-diagnosed chronic obstructive pulmonary disease (n = 313,958) and incident cases of a first myocardial infarction (n = 422,344), lung cancer (n = 116,629), hip fracture (n = 53,756), depression (n = 93 038), and diabetes mellitus (n = 292 228). Multivariate adjusted hazard ratios for life-time association with ever-diagnosed chronic obstructive pulmonary disease were 1.26 (95% CI 1.25-1.27) for myocardial infarction, 2.05 (2.03-2.08) for lung cancer, 2.12 (2.07-2.17) for hip fracture, 1.74 (1.70-1.77) for depression, and 1.21 (1.20-1.23) for diabetes mellitus, compared with controls; these risk estimates were highest in women and the youngest age groups. Before the first hospitalization with chronic obstructive pulmonary disease, multivariate adjusted odds ratios were 1.47 (1.44-1.49) for myocardial infarction, 3.68 (3.52-3.84) for lung cancer, 1.16 (1.13-1.18) for hip fracture, 1.88 (1.80-1.96) for depression, and 1.16 (1.13-1.18) for diabetes mellitus, compared with matched controls. Corresponding values after a chronic obstructive pulmonary disease hospitalization were 0.74 (0.73-0.76), 1.48 (1.45-1.51), 1.23 (1.20-1.27), 1.21 (1.18-1.24), and 0.83 (0.81-0.85), respectively.

CONCLUSION

Chronic obstructive pulmonary disease was associated with higher rates of myocardial infarction, lung cancer, diabetes, hip fracture, and depression, but the strength of these associations was modified after a first admission for chronic obstructive pulmonary disease. These associations may be related to common genetic and/or lifestyle/environmental risk factors, and therefore these factors are likely to have an adverse health impact rather than chronic obstructive pulmonary disease per se.

[Forecasting model of risk of cancer in lung cancer pedigree in a case-control study]

背景与目的

对人群每年进行低剂量胸部CT筛查可提高早期肺癌诊断率，但其假阳性率较高，常导致不必要的手术。本研究拟建立肺癌家系风险度预测模型，从中细分高危人群，从而提高筛选效能。

方法

以经病理确诊的肺癌患者的家系作为研究人群，同时收集先证者的配偶家系作为对照家系，共收集先证者家系633例和对照家系565例。应用SPSS 17.0进行统计学分析。

结果

先证者家系一级亲属患肿瘤的风险性为对照组家系一级亲属的1.71倍（OR=1.71, P < 0.001）。家系中患癌个数分别为=1和≥2的两组与对照组比较有统计学差异（P=0.005, P=0.002）。建立回归模型后赋值得到与普通人群相比的肺癌风险度为0.38-63.08（倍）。风险度为普通人群10倍以上的群体，应用本模型的正确率为88.1%。

结论

如果一级亲属患癌个数越多，患肺癌的风险越高。根据本研究建立的风险度预测模型，风险度达普通人群10倍以上的主要为重度吸烟的吸烟人群，应加强筛查。特点为：有肺部既往疾病史的重度吸烟人群，加上男性、职业暴露和一级亲属肿瘤家族史三项中的任一项；有肺部既往疾病史或重度吸烟的人群中，有职业暴露的男性且一级亲属有不少于两位肿瘤患者。

[Comorbidities in COPD: a new challenge in clinical practice]

Today it is a recognised fact that chronic obstructive pulmonary disease (COPD) is a real systemic disease that is respiratory-based. Recently, the focus has been on the importance of the comorbidities that are associated with COPD, such as all the cardiovascular diseases, lung cancer, diabetes, metabolic syndrome, peripheral muscular dysfunction, depression, anxiety, osteoporosis and anaemia, etc. These comorbidities constitute a new medical and therapeutic challenge with regard to COPD; their high frequency and considerable impact on the quality of life and the prognosis for survival of the patients make them a key element. The aims of this focus are to present the spectrum and prevalence of comorbidities in COPD, to obtain an objective view as to why and how these comorbidities should be systematically assessed and treated in patients, and subsequently to discuss the impact of this new data in clinical practice and in research. This recent data is another positive step in understanding the disease, optimising the diagnosis, and assessing and caring for COPD patients.

Malignancies following lung transplantation

Malignancy is an important complication of thoracic organ transplantation and is associated with significant morbidity and mortality. Lung transplant recipients are at greater risk for cancer than immunocompetent persons, with cancer-specific incidence rates up to 60-fold higher than the general population. The increased risk for cancer is attributed to neoplastic properties of immunosuppressive medications, oncogenic viruses, and cancer-specific risk factors. This article addresses the epidemiology, presentation, and treatment of the most common malignancies after lung transplantation, including skin cancer, posttransplant lymphoproliferative disorder, and bronchogenic carcinoma.

Pleiomorphic adenoma gene-like 2 expression is associated with the development of lung adenocarcinoma and emphysema

Previous study of transgenic mice with long-term expression of pleiomorphic adenoma gene-like 2 (PLAGL2), a surfactant protein C (SP-C) transactivator, in type II cells showed the manifestation of centrilobular emphysema in vivo. Since emphysema is an independent risk factor for bronchogenic carcinoma, we hypothesized that the mouse lungs with induced PLAGL2-expression had increased incidences in developing lung adenocarcinoma. To test the hypothesis, mouse lungs were examined for the presence of tumors. Male mice with induced PLAGL2-expression in the lungs were more vulnerable to tumorigenesis than female mice (p<0.05). Epithelial cells expressing pro-SP-C and Clara cell secretory protein (CCSP) at the terminal bronchioles and the bronchoalveolar duct junction (BADJ) were increased in the induced transgenic mice, suggesting a role of PLAGL2 in expanding SP-C expression cells. Co-expression of TTF-1, pro-SP-C and CD133 (a stem-cell marker) in cancer and distal airway epithelial cells indicated that both cells were derived from common progenitors. This result supported a common-cell-origin mechanism for the comorbid diseases - emphysema and lung cancer. Furthermore, a public lung cancer gene expression profiling database was examined to determine the relevance of PLAGL2 expression and lung adenocarcinoma in humans. Patients with high PLAGL2 expression in lung tumors were readily found. Female patients (N=218) with low PLAGL2 expression (the lowest quartile of total patients) at the early-stage of disease had better prognosis in survival. Male patients, on the other hand, had no such correlation. Generally, their survival rate was significantly poorer than of female patients. Taken together, our data suggested a pathological role of PLAGL2 in lung adenocarcinoma development and a preferable prognosis of low PLAGL2 expression in female patients.