Lung cancer: a nationwide analysis of sex and age incidence trends from 1980 to 2022.

BACKGROUND: Lung cancer, once rare, has evolved into the global leading cause of cancer-related mortality, primarily driven by widespread cigarette smoking in the 20th century. This study explores the historical trends of lung cancer incidence in Denmark over four decades, emphasizing the impact of smoking prevalence, age, and gender on the observed patterns. MATERIALS AND METHODS: Drawing upon data from the Danish National Patient Register and information on smoking habits provided by the Danish Health Authority, this study investigates lung cancer incidence rates, demographic shifts, and smoking prevalence from 1980 to 2022. RESULTS: Smoking prevalence exhibited a consistent decline in males from 1950 to 2022, whereas female smoking prevalence maintained a stable level from 1950 to 1987, followed by a subsequent decline from 1987 to 2022. A peak in lung cancer crude incidence rates was identified during 2014-2017, with no significant difference observed before and after this period. Over the period, the gender distribution transitioned from a male majority to an equal male-female ratio, and age-specific disparities indicated declines in patients aged 50-59 and increases in those above 80 years. INTERPRETATION: The certainty of a decline in lung cancer incidence in the coming years remains unclear. Based on smoking prevalence, it might still be a decade away. To ensure a sustained decline in lung cancer incidence, targeted interventions are imperative, including customized smoking cessation programs that could be designed favorably for females. Given the modest decline in smoking prevalence over the last decade, legislation aimed at discouraging young individuals from smoking is pivotal. As of now, these efforts have not been implemented in Denmark.

Consequences of Losing Incidental Pulmonary Nodules to Follow-Up: Unmonitored Nodules Progressing to Stage IV Lung Cancer.

INTRODUCTION: Lung cancer is the leading cause of cancer-related death globally. Incidental pulmonary nodules represent a golden opportunity for early diagnosis, which is critical for improving survival rates. This study explores the impact of missed pulmonary nodules on the progression of lung cancer. METHODS: A total of 4,066 stage IV lung cancer cases from 2019 to 2021 in Danish hospitals were investigated to determine whether a chest computed tomography (CT) had been performed within 2 years before diagnosis. CT reports and images were reviewed to identify nodules that had been missed by radiologists or were not appropriately monitored, despite being mentioned by the radiologist, and to assess whether these nodules had progressed to stage IV lung cancer. RESULTS: Among stage IV lung cancer patients, 13.6% had undergone a chest CT scan before their diagnosis; of these, 44.4% had nodules mentioned. Radiologists missed a nodule in 7.6% of cases. In total, 45.3% of nodules were not appropriately monitored. An estimated 2.5% of stage IV cases could have been detected earlier with proper surveillance. CONCLUSION: This study underlines the significance of monitoring pulmonary nodules and proposes strategies for enhancing detection and surveillance. These strategies include centralized monitoring and the implementation of automated registries to prevent gaps in follow-up.

Free diving-inspired breathing techniques for COPD patients: A pilot study.

Objectives: Pulmonary rehabilitation (PR) is a key factor in enhancing self-management and exercise capacity in patients with chronic obstructive pulmonary disease (COPD). The content and length of PR varies between countries and authorities responsible for rehabilitation. After completion of rehabilitation, it is often difficult for patients to stay motivated and perform regular exercise. Methods: In this pilot study, nine patients with moderate to severe COPD completed a 6-week training programme consisting of free diving-inspired breathing techniques, designed to be incorporated into daily activities. Results: Participants significantly increased the distance walked in 6 min by 48 m (p < 0.05) and a significant reduction was seen on the COPD self-efficacy scale (p < 0.05). Furthermore, adherence to the programme sessions was very high at 96.3% and no adverse events occurred. Discussion: This pilot study tested the feasibility of introducing breathing techniques used by COPD patients to enhance their walking capacity. The techniques were well tolerated and participant's adherence to the weekly group sessions was high.

Long chain n-3 polyunsaturated fatty acids and vascular function in patients with chronic kidney disease and healthy subjects: a cross-sectional and comparative study.

BACKGROUND: Patients with chronic kidney disease have a markedly increased cardiovascular mortality compared with the general population. Long chain n-3 polyunsaturated fatty acids have been suggested to possess cardioprotective properties. This cross-sectional and comparative study evaluated correlations between hemodynamic measurements, resistance artery function and fish consumption to the content of long chain n-3 polyunsaturated fatty acids in adipose tissue, a long-term marker of seafood intake. METHODS: Seventeen patients with chronic kidney disease stage 5 + 5d and 27 healthy kidney donors were evaluated with hemodynamic measurements before surgery; from these subjects, 11 patients and 11 healthy subjects had vasodilator properties of subcutaneous resistance arteries examined. The measurements were correlated to adipose tissue n-3 polyunsaturated fatty acids. Information on fish intake was obtained from a dietary questionnaire and compared with adipose tissue n-3 polyunsaturated fatty acids. RESULTS: Fish intake and the content of n-3 polyunsaturated fatty acids in adipose tissue did not differ between patients and controls. n-3 polyunsaturated fatty acid levels in adipose tissue were positively correlated to systemic vascular resistance index; (r = 0.44; p = 0.07 and r = 0.62; p < 0.05, chronic kidney disease and healthy subjects respectively) and negatively correlated to cardiac output index (r = -0.69; p < 0.01 and r = -0.50; p < 0.05, chronic kidney disease and healthy subjects respectively). No correlation was observed between n-3 polyunsaturated fatty acid levels in adipose tissue and vasodilator properties in resistance arteries. n-3 PUFA content in adipose tissue increased with increasing self-reported fish intake. CONCLUSIONS: The correlations found, suggest a role for n-3 polyunsaturated fatty acids in hemodynamic properties. However, this is apparently not due to changes in intrinsic properties of the resistance arteries as no correlation was found to n-3 polyunsaturated fatty acids.

Introduction of the Danish Lung Nodule Registry: A part of the Danish Lung Cancer Registry.

BACKGROUND: The majority of lung cancer cases are diagnosed late, resulting in poor prognosis and high mortality rates. Early detection and management of lung cancer can improve patient outcomes and reduce mortality rates. Pulmonary nodules are key factors in the early detection of lung cancer, they are common in high-risk populations and require correct classification to determine whether they are benign or malignant. Over the last decade a steep increase in the number of thoracic CT scans has been seen in Denmark, resulting in substantial resources allocated to CT follow-up of incidentally detected pulmonary nodules. The implementation of a nationwide Danish prospective pulmonary nodule registry is to methodically record pulmonary nodules and thereby evaluate the scope of pulmonary nodule follow-up, the nature of the nodules, and the clinical progression of patients with pulmonary nodules. METHODS: A prospective pulmonary nodule registry (Danish Lung Nodule Registry) will be a natural appendix to the Danish Lung Cancer Registry. Three new ICD-10 classification codes will be introduced, defining the type of nodule: /DR91.1/ Solid nodule /DR91.2/ Part-solid nodule; /DR91.3/ Non-solid nodule. Furthermore, an additional letter will describe whether the imaging exam is performed on suspicion of lung cancer (A), or the finding is incidental (B). Registration of the nodules will be performed by the departments of respiratory medicine who manage follow-up of pulmonary nodules. It is estimated that around 7000 nodules will be registered annually. DISCUSSION: The registration of patients in the lung nodule registry complies with current Danish legislation. The registry will be seamlessly integrated with other nationwide Danish registries, including the Danish Lung Cancer Registry, to collect additional patient data and improve the quality and scope of the data acquired. The results from these comprehensive epidemiological studies will be of significant interest and offer valuable research opportunities.

Management of incidental pulmonary nodules in CT examination.

Lung cancer is the leading cause of cancer-related death in Denmark and the world. The increase in CT examinations has led to an increase in detection of pulmonary nodules divided into solid and subsolid (including ground glass and part solid). Risk factors for malignancy include age, smoking, female gender, and specific ethnicities. Nodule traits like size, spiculation, upper-lobe location, and emphysema correlate with higher malignancy risk. Managing these potentially malignant nodules relies on evidence-based guidelines and risk stratification. These risk stratification models can standardize the approach for the management of incidental pulmonary findings, as argued in this review.

Methylated Cell-Free Tumor DNA in Sputum as a Tool for Diagnosing Lung Cancer-A Systematic Review and Meta-Analysis.

Lung cancer is the leading cause of cancer-related mortality worldwide. Early diagnosis is pivotal for the prognosis. There is a notable overlap between lung cancer and chronic bronchitis, and the potential use of methylated tumor DNA in sputum as a biomarker for lung cancer detection is appealing. This systematic review and meta-analysis followed the PRISMA 2020 statement. A comprehensive search was conducted in Embase, Medline, Web of Science, and the Cochrane Library, using these search strings: Lung cancer, sputum, and methylated tumor DNA. A total of 15 studies met the eligibility criteria. Studies predominantly utilized a case-control design, with sensitivity ranging from 10 to 93% and specificity from 8 to 100%. A meta-analysis of all genes across studies resulted in a summary sensitivity of 54.3% (95% CI 49.4-59.2%) and specificity of 79.7% (95% CI 75.0-83.7%). Notably, two less explored genes (TAC1, SOX17) demonstrated sensitivity levels surpassing 85%. The study's findings highlight substantial variations in the sensitivity and specificity of methylated tumor DNA in sputum for lung cancer detection. Challenges in reproducibility could stem from differences in tumor site, sample acquisition, extraction methods, and methylation measurement techniques. This meta-analysis provides a foundation for prioritizing high-performing genes, calling for a standardization and refinement of methodologies before potential application in clinical trials.

Lung cancer among outpatients with COPD: a 7-year cohort study.

Introduction: Lung cancer (LC) is the most common cause of cancer-related deaths worldwide, and its prognosis upon metastasis remains poor. Patients with COPD face a significantly elevated LC risk, up to six times greater than those with normal lung function. We aimed to investigate LC prevalence and stage distribution among COPD outpatients. Furthermore, we aimed to outline the COPD-related variables associated with referral for LC examination. Methods: We conducted a retrospective analysis encompassing the period from 1 January 2012 to 31 December 2018 on all outpatients with COPD and LC and individuals referred for LC examinations. Results: Among all COPD outpatients, 2231 patients (18%) were referred for LC examinations and 565 (4.6%) were diagnosed with LC. LC patients with COPD were more likely to be stage I-II, in contrast to the non-COPD LC population (46% versus 26%, p<0.001 for all). Patients referred for LC examinations exhibited higher use of COPD-related medications, reported more severe dyspnoea (69% versus 66% with Medical Research Council dyspnoea score >2) and experienced a greater frequency of exacerbations (30% versus 24% with two or more exacerbations). Conclusion: Our study revealed a notably high LC incidence among COPD outpatients. LC patients with COPD were diagnosed at earlier stages, and outpatients with more pronounced COPD symptoms were more inclined to undergo LC diagnostics. The overrepresentation of LC cases among COPD outpatients emphasises the importance of tailoring specific screening initiatives for this demographic.

Methylated Circulating Tumor DNA in Blood as a Tool for Diagnosing Lung Cancer: A Systematic Review and Meta-Analysis.

Lung cancer is the leading cause of cancer-related deaths, and early detection is crucial for improving patient outcomes. Current screening methods using computed tomography have limitations, prompting interest in non-invasive diagnostic tools such as methylated circulating tumor DNA (ctDNA). The PRISMA guidelines for systematic reviews were followed. The electronic databases MEDLINE, Embase, Web of Science, and Cochrane Library were systematically searched for articles. The search string contained three main topics: Lung cancer, blood, and methylated ctDNA. The extraction of data and quality assessment were carried out independently by the reviewers. In total, 33 studies were eligible for inclusion in this systematic review and meta-analysis. The most frequently studied genes were SHOX2, RASSF1A, and APC. The sensitivity and specificity of methylated ctDNA varied across studies, with a summary sensitivity estimate of 46.9% and a summary specificity estimate of 92.9%. The area under the hierarchical summary receiver operating characteristics curve was 0.81. The included studies were generally of acceptable quality, although they lacked information in certain areas. The risk of publication bias was not significant. Based on the findings, methylated ctDNA in blood shows potential as a rule-in tool for lung cancer diagnosis but requires further research, possibly in combination with other biomarkers.

Assessment of circulating biomarkers for detection of lung cancer in a high-risk cohort.

BACKGROUND: There is an urgent need for early detection of lung cancer. Screening with low-dose computed tomography (LDCT) is now implemented in the US. Supplementary use of a lung cancer biomarker with high specificity is desirable. OBJECTIVE: To assess the diagnostic properties of a biomarker panel consisting of cytokeratin 19 fragment (CYFRA 21-1), carcinoembryonic antigen (CEA) and cancer antigen 125 (CA125). METHODS: A cohort of 250 high-risk patients was investigated on suspicion of lung cancer. Ahead of diagnostic work-up, blood samples taken. Cross-validated prediction models were computed to assess lung cancer detection properties. RESULTS: In total 32% (79/250) of patients were diagnosed with lung cancer. Area under the curve (AUC) for the three biomarkers was of 0.795, with sensitivity/specificity of 57%/93% and negative predictive value of 83%. When combining the biomarkers with US screening criteria, the AUC was 0.809, while applying only US screening criteria on the cohort, yielded an AUC of 0.62. The ability of the biomarkers to detect stage I-II lung cancer was substantially lower; AUC 0.54. CONCLUSIONS: In a high-risk cohort, the detection properties of the three biomarkers were acceptable compared to current LDCT screening criteria. However, the ability to detect early stage lung cancer was low.

Natural killer cell activity as a biomarker for the diagnosis of lung cancer in high-risk patients.

OBJECTIVE: Natural killer (NK) cells play an essential role in the immune response against cancer. However, immune escape mechanisms may cause inferior NK cell activity (NKA) in patients with cancer. This prospective study examined the relationship between NKA and lung cancer in a high-risk cohort. METHODS: In a cohort study, 250 participants referred by their general practitioner for suspicion of lung cancer were included. Before clinical investigation, blood was collected into NK Vue tubes, and the level of interferon gamma after 24 hours served as a surrogate marker for NKA. RESULTS: Among 250 patients, 79 were diagnosed with lung cancer. No difference in NKA was found between patients with lung cancer and control participants in which lung cancer was ruled out (median 226 pg/mL vs. 450 pg/mL). However, there was a significant difference in NKA between patients with late-stage lung cancer and controls (median 161 pg/mL vs. 450 pg/mL). A linear regression model showed that NKA was not influenced by age, sex or smoking status. CONCLUSIONS: The significantly lower NKA in patients with late-stage lung cancer warrants further investigation combining NKA with other biomarkers and examining the potential role of NKA as a marker of disseminated disease.

Intrapleural fibrinolysis and DNase versus video-assisted thoracic surgery (VATS) for the treatment of pleural empyema (FIVERVATS): protocol for a randomised, controlled trial - surgery as first-line treatment.

INTRODUCTION: Pleural empyema is a frequent disease with a high morbidity and mortality. Current standard treatment includes antibiotics and thoracic ultrasound (TUS)-guided pigtail drainage. Simultaneously with drainage, an intrapleural fibrinolyticum can be given. A potential better alternative is surgery in terms of video-assisted thoracoscopic surgery (VATS) as first-line treatment. The aim of this study is to determine the difference in outcome in patients diagnosed with complex parapneumonic effusion (stage II) and pleural empyema (stage III) who are treated with either VATS surgery or TUS-guided drainage and intrapleural therapy (fibrinolytic (Alteplase) with DNase (Pulmozyme)) as first-line treatment. METHODS AND ANALYSIS: A national, multicentre randomised, controlled study. Totally, 184 patients with a newly diagnosed community acquired complicated parapneumonic effusion or pleural empyema are randomised to either (1) VATS procedure with drainage or (2) TUS-guided pigtail catheter placement and intrapleural therapy with Actilyse and DNase. The total follow-up period is 12 months. The primary endpoint is length of hospital stay and secondary endpoints include for example, mortality, need for additional interventions, consumption of analgesia and quality of life. ETHICS AND DISSEMINATION: All patients provide informed consent before randomisation. The research project is carried out in accordance with the Helsinki II Declaration, European regulations and Good Clinical Practice Guidelines. The Scientific Ethics Committees for Denmark and the Danish Data Protection Agency have provided permission. Information about the subjects is protected under the Personal Data Processing Act and the Health Act. The trial is registered at www. CLINICALTRIALS: gov, and monitored by the regional Good clinical practice monitoring unit. The results of this study will be published in peer-reviewed journals and presented at various national and international conferences. TRIAL REGISTRATION NUMBER: NCT04095676.

Symptoms and lung function follow-up after lung cancer resection.

INTRODUCTION In recent decades, lung cancer is being diagnosed at ever earlier stages, leading to higher resection rates and improved survival. Therefore, more patients live with the sequelae of thoracic surgery. The standardised Danish follow-up programme after lung cancer resection includes CT and clinical evaluation at set times. METHODS An e-mail survey was conducted to evaluate local practices at lung cancer investigation sites with respect to the setup of follow-up programmes after lung cancer resection. In addition, 50 consecutive patients were seen three months after their lung cancer resection. Spirometry was performed and patients reported on their use of inhalation medicine, smoking status and quality of life. RESULTS The study revealed heterogeneous setups regarding routine spirometry (5/12 sites) and assessment by a respiratory physician (6/12). In a single-centre study including 50 patients three months after lung cancer resection, 22% of patients were using a bronchodilator even though 50% of patients were obstructive on spirometry and 48% reported shortness of breath (SOB). 17% of patients were active smokers, whereas the majority reported symptoms of a physical nature such as fatigue, SOB and cough. CONCLUSIONS It is important to establish the optimal follow-up setup with an emphasis on detection of recurrence, symptom improvement and smoking cessation. This study highlighted the importance of symptom assessment by a respiratory physician/nurse. A spirometry should be performed if patients experience SOB and the potential benefit of inhalation medicine should be assessed. FUNDING none. TRIAL REGISTRATION not relevant.

Geographical and socioeconomic differences in compliance with and access to allergen immunotherapy in Denmark: A nationwide registry-based study - 1998-2016.

BACKGROUND: Allergen immunotherapy (AIT) is a cost-effective treatment option in moderate-severe allergic rhino-conjunctivitis. Inequality in access to AIT and variation in compliance related to socioeconomic status or geographical location have not been described previously. OBJECTIVE: The aim of the study was to evaluate access to grass pollen AIT at various educational attainment levels in the five regions of Denmark. Furthermore, grass pollen AIT treatment compliance was evaluated with respect to age, educational attainment and geographical area. METHODS: The unique civil registration number of every citizen in Denmark was combined with the nationwide Danish National Health Service Prescription Database and Statistics Denmark Database to extract age, gender, residence and educational attainment of every citizen who collected prescribed AIT medication from 1998 to 2016. Then, compliance and use of AIT were calculated with respect to age, geographical location and educational attainment. RESULTS: The use of subcutaneous AIT (SCIT) was significantly higher in the Capital Region; this difference was less predominant for sublingual AIT (SLIT). People who were educated only to primary school or vocational training levels were less frequent users of AIT. Compliance was especially low in the Capital Region and among people educated only to primary school level. In the age groups, compliance was similar, apart from SLIT users aged 0-9, for whom compliance was higher. CONCLUSION: This nationwide study finds that SLIT has the potential to reduce inequality in access to AIT. A focus intervention is needed to facilitate access to and compliance with AIT in groups with lower socioeconomic status.

Performance of the EarlyCDT® Lung test in detection of lung cancer and pulmonary metastases in a high-risk cohort.

OBJECTIVES: Early detection of lung cancer is pivotal for an optimal prognosis. CT screening is currently implemented in USA. To decrease the amount of CT scans, the application of a blood-based biomarker as part of screening criteria is desirable. MATERIALS AND METHODS: The EarlyCDT® Lung test was performed in a high-risk cohort composed 246 patients referred from their GP on suspicion of lung cancer. Blood samples were taken at first visit and patients underwent diagnostic workup on suspicion of lung cancer resulting in either a malignant diagnosis or ruled out cancer. Sensitivity and specificity of the EarlyCDT® Lung were calculated in the cohort and subgroups based on age, smoking history, sex and lung cancer stage. RESULTS: Overall sensitivity in the cohort was 33 % for lung cancer and 31 % for primary lung cancer and lung metastases combined. Sensitivity in age groups was 11 % (60 years or below), 31 % (61-75 years) and 55 % (>75 years). In patients with at least 10 tobacco pack years, sensitivity was 33 % while the sensitivity in patients with at least 50 tobacco pack years was 44 %. The assay sensitivity in stage I-II lung cancer patients was 21 %, while this was 40 % in stage III-IV lung cancer patients. In a subgroup of patients that met current CT screening criteria (age 55-80 years and minimum 30 tobacco pack years) the sensitivity was 37 %. CONCLUSION: The rationale of screening for lung cancer is to find patients in an early and resectable stage. However, the EarlyCDT® Lung test performed best in elderly, late stage lung cancer patients with a heavy smoking history. Based on these results, the current study finds insufficient sensitivity of the EarlyCDT® Lung test to be used as part of inclusion criteria in a low-dose CT program for detection of lung cancer.

Compliance in subcutaneous and sublingual allergen immunotherapy: A nationwide study.

INTRODUCTION: Allergic rhino-conjunctivitis is a highly prevalent condition. In moderate to severe cases, allergen immunotherapy (AIT) is a cost-effective therapeutic option. Previous data have reported a large difference in treatment compliance of subcutaneously (SCIT) and sublingually (SLIT) administered AIT. METHODS: By use of the unique civil registration number assigned to all Danish citizens and the Danish National Health Service Prescription Database, compliance rates of all patients prescribed with grass pollen AIT from January 1998 until December 2016 were analysed annually during the three-year treatment period. RESULTS: The male/female ratio was close to 1:1 in SCIT, while SLIT was more frequently used by men. A large proportion of users was children or adolescents (32% and 45%, SCIT and SLIT, respectively). Compliance of both subcutaneous and sublingual treatment gradually fell each year; compliance in year 3 was 57% and 53% for subcutaneous and sublingual treatment, respectively. Compliance of grass pollen sublingual treatment was also analysed each year after registration on the Danish market. Compliance significantly increased following the introduction and stabilised on a relatively high level. CONCLUSION: Based on previous studies, we hypothesised that AIT compliance would be low, especially in SLIT. However, in Denmark, compliance in SCIT and SLIT was almost similar, and the majority of patients completed the three-year treatment period with a compliance in the last quintile.

Hemodynamics and function of resistance arteries in healthy persons and end stage renal disease patients.

INTRODUCTION: Cardiovascular disease is the leading cause of death in patients with end stage renal disease (ESRD). The vasodilator mechanisms in small resistance arteries are in earlier studies shown to be reduced in patients with end stage renal disease. We studied whether endothelium dependent vasodilatation were diminished in ESRD patients and the interaction between the macro- and microcirculation. METHODS: Eleven patients with ESRD had prior to renal transplant or insertion of peritoneal dialysis catheter measured pulse wave velocity. During surgery, a subcutaneous fat biopsy was extracted. Resistance arteries were then dissected and mounted on a wire myograph for measurements of dilator response to increasing concentrations of acetylcholine after preconstriction with noradrenaline. Twelve healthy kidney donors served as controls. RESULTS: Systolic blood pressure was elevated in patients compared to the healthy controls; no difference in the concentration of asymmetric dimethyl arginine was seen. No significant difference in the endothelium dependent vasodilatation between patients and controls was found. Correlation of small artery properties showed an inverse relationship between diastolic blood pressure and nitric oxide dependent vasodilatation in controls. Pulse pressure was positively correlated to the total endothelial vasodilatation in patients. A negative association between S-phosphate and endothelial derived hyperpolarisation-like vasodilatation was seen in resistance arteries from controls. CONCLUSION: This study finds similar vasodilator properties in kidney patients and controls. However, correlations of pulse pressure and diastolic blood pressure with resistance artery function indicate compensating measures in the microcirculation during end stage renal disease.