Lung Cancer in Never-Smokers: A Multicenter Case-Control Study in North China

Investigating Causal Associations of Diet Compositions with the Risk of Lung Cancer

OBJECTIVE

This study aimed to investigate the causal relationship between diet compositions and lung cancer (LC) risk.

METHODS

A two-sample Mendelian randomization (MR) analysis was performed to assess the causal relationship between diet and LC risk, including three LC subtypes. Instrumental variables (IVs) for three diet compositions were selected from genome-wide association studies (GWAS). Summary statistics for LC and its subtypes came from the largest meta-analysis. The inverse-variance weighted (IVW) method was used as the main MR analysis, with sensitivity analyses to ensure result robustness. Then, we conducted an observational study using data from National Health and Nutrition Examination Survey (NHANES) to verify the relationship.

RESULTS

Our results showed significant evidence that fat intake was correlated with the lower risk of lung adenocarcinoma. There were also suggestive correlations between fat intake and overall LC. However, no significant associations were found between other macronutrients and LC risk. NHANES data further showed that higher polyunsaturated fatty acid (PUFA) intake was linked to better outcomes in LC patients.

CONCLUSION

PUFA intake may have a protective effect against LC. Adjusting dietary proportions could potentially help in the primary prevention of LC.

Current Evidence for a Lung Cancer Screening Program

Background

Lung cancer screening is still in an early phase compared to other cancer screening programs, despite its high lethality particularly when diagnosed late. Achieving early diagnosis is crucial to obtain optimal outcomes.

Summary

In this review, we will address the current evidence on lung cancer screening through low-dose computed tomography (LDCT) and its impact on mortality reduction, existing screening recommendations, patient eligibility criteria, screening frequency and duration, benefits and harms, cost-effectiveness and some insights on lung cancer screening implementation and adoption. Additionally, new non-imaging, noninvasive biomarkers with high diagnostic potential are also briefly highlighted.

Key Messages

LDCT screening in a prespecified population based on age and smoking history proved to reduce lung cancer mortality. Optimization of the target population and management of LDCT pitfalls can further improve lung cancer screening efficiency and cost-effectiveness. Novel screening technologies and biomarkers being studied can potentially be game-changers in lung cancer screening and diagnosis.

Radiomics signature based on robust features derived from diffusion data for differentiation between benign and malignant solitary pulmonary lesions

BACKGROUND

Classifying and characterizing pulmonary lesions are critical for clinical decision-making process to identify optimal therapeutic strategies. The purpose of this study was to develop and validate a radiomics nomogram for distinguishing between benign and malignant pulmonary lesions based on robust features derived from diffusion images.

MATERIAL AND METHODS

The study was conducted in two phases. In the first phase, we prospectively collected 30 patients with pulmonary nodule/mass who underwent twice EPI-DWI scans. The robustness of features between the two scans was evaluated using the concordance correlation coefficient (CCC) and dynamic range (DR). In the second phase, 139 patients who underwent pulmonary DWI were randomly divided into training and test sets in a 7:3 ratio. Maximum relevance minimum redundancy, least absolute shrinkage and selection operator, and logistic regression were used for feature selection and construction of radiomics signatures. Nomograms were established incorporating clinical features, radiomics signatures, and ADC(0, 800). The diagnostic efficiency of different models was evaluated using the area under the curve (AUC) and decision curve analysis.

RESULTS

Among the features extracted from DWI and ADC images, 42.7% and 37.4% were stable (both CCC and DR ≥ 0.85). The AUCs for distinguishing pulmonary lesions in the test set for clinical model, ADC, ADC radiomics signatures, and DWI radiomics signatures were 0.694, 0.802, 0.885, and 0.767, respectively. The nomogram exhibited the best differentiation performance (AUC = 0.923). The decision curve showed that the nomogram consistently outperformed ADC value and clinical model in lesion differentiation.

CONCLUSION

Our study demonstrates the robustness of radiomics features derived from lung DWI. The ADC radiomics nomogram shows superior clinical net benefits compared to conventional clinical models or ADC values alone in distinguishing solitary pulmonary lesions, offering a promising tool for noninvasive, precision diagnosis in lung cancer.

Health effects associated with exposure to secondhand smoke: a Burden of Proof study

Despite a gradual decline in smoking rates over time, exposure to secondhand smoke (SHS) continues to cause harm to nonsmokers, who are disproportionately children and women living in low- and middle-income countries. We comprehensively reviewed the literature published by July 2022 concerning the adverse impacts of SHS exposure on nine health outcomes. Following, we quantified each exposure-response association accounting for various sources of uncertainty and evaluated the strength of the evidence supporting our analyses using the Burden of Proof Risk Function methodology. We found all nine health outcomes to be associated with SHS exposure. We conservatively estimated that SHS increases the risk of ischemic heart disease, stroke, type 2 diabetes and lung cancer by at least around 8%, 5%, 1% and 1%, respectively, with the evidence supporting these harmful associations rated as weak (two stars). The evidence supporting the harmful associations between SHS and otitis media, asthma, lower respiratory infections, breast cancer and chronic obstructive pulmonary disease was weaker (one star). Despite the weak underlying evidence for these associations, our results reinforce the harmful effects of SHS on health and the need to prioritize advancing efforts to reduce active and passive smoking through a combination of public health policies and education initiatives.

Paracelsian 'Bergsucht' - lung cancer or radiation-induced fibrosis?

PURPOSE

Assessment of absorbed doses on organs and tissues of miners during radon exposure in the Schneeberg mines in the sixteenth century and calculation of the probability of occurrence of radiation-induced lung cancer and lung fibrosis, considering the life expectancy characteristic and the absence of smoking.

MATERIALS AND METHODS

The expected radon concentration at the Schneeberg mines has been estimated using published data. Modeling of the accumulation of radon in the working tunnels of mine workings was carried out using the RESRAD-Build 4.0, based on the radium concentration in soil and geometric parameters of the mining tunnel from the engravings in Agricola's book. The dynamics of radionuclides in the human body were performed using the WinAct software in accordance with data from ICRP Publications 130 and 137. The values of absorbed doses on the tissues of the respiratory tract were obtained using the IDAC 2.1 program. Several models based on the epidemiology of uranium miners have been used to calculate radiation risks from radon exposure. The probability of male survival at birth and the age-specific frequency of spontaneous lung cancer not associated with radiation for miners of the sixteenth century (nonsmoking men aged 20-40 years) were estimated to properly calculate the radiation risks.

RESULTS

The expected radon concentration in the Schneeberg mines was assessed in the range of 75-100 kBq m-3. The average value of the equilibrium factor was estimated as 0.49 ± 0.03. The annual exposure of miners to radon decay products was assessed as 125-165 WLM year-1. The annual values of absorbed doses to different sections of the respiratory tract were calculated, the maximum absorbed doses of α-radiation are formed on the bronchial and bronchiolar regions of the lungs (2.23 Gy year-1). The deterministic effects as radiation fibrosis of the lungs with 10 years of experience in the mines of Schneeberg have a probability of occurrence from 60 to 100%. All the models used for radiation risk assessments showed that the lifetime risk of developing lung cancer for nonsmoking Schneeberg miners is many times lower than the risk of developing deterministic radiation effects. In contrast, for the smoking cohort of miners in the nineteenth century lung cancer become the dominant cause of death.

CONCLUSIONS

The deterministic radiation effects of Schneeberg miners in sixteenth century, exposed to extremely high levels of radon, such as radiation pneumosclerosis or pulmonary fibrosis, are more likely than the development of radiation-induced lung cancer.

Overview and countermeasures of cancer burden in China

Cancer is one of the leading causes of human death worldwide. Treatment of cancer exhausts significant medical resources, and the morbidity and mortality caused by cancer is a huge social burden. Cancer has therefore become a serious economic and social problem shared globally. As an increasingly prevalent disease in China, cancer is a huge challenge for the country's healthcare system. Based on recent data published in the Journal of the National Cancer Center on cancer incidence and mortality in China in 2016, we analyzed the current trends in cancer incidence and changes in cancer mortality and survival rate in China. And also, we examined several key risk factors for cancer pathogenesis and discussed potential countermeasures for cancer prevention and treatment in China.

Lung cancer in never smokers (LCINS): development of a UK national research strategy

INTRODUCTION

Lung cancer in never smokers (LCINS) accounts for 15% of lung cancers diagnosed in the UK, making it the 8th most common cancer. There are few robust studies specific to the LCINS population making data surrounding the incidence and mortality of LCINS incomplete, leaving many gaps in our understanding of the needs of this population.

METHODS

To address a lack of research in this important area, the UK National Cancer Research Institute Lung Study Group (NCRI-LSG) undertook a national survey and hosted a research strategy day to define key research priorities. A wide cross section of stakeholders, including patient advocates, the charitable sector, basic and translational researchers, and multi-disciplinary healthcare professionals contributed highlighting their research priorities.

RESULTS

One-hundred twenty-seven surveys were completed (52 by patients/patient advocates) prior to the strategy day. These identified themes for expert review presentations and subsequent workshop discussions at the national research strategy day, which registered 190 attendees (50 patients/patient advocates). The four key themes that emerged to form the basis of a research strategy for LCINS are (1) Raising awareness, (2) Risk assessment and early detection, (3) Disease biology, (4) Living with and beyond.

CONCLUSION

This paper summarises current evidence and important gaps in our knowledge related to LCINS. We present recommendations for a national research strategy aimed at improving outcomes for patients.

Where there are fumes, there may be lung cancer: a systematic review on the association between exposure to cooking fumes and the risk of lung cancer in never-smokers

PURPOSE

Lung cancer in never-smokers (LCINS) is the seventh leading cause of cancer, and exposure to cooking fumes has recently emerged as a potential risk factor. This systematic review is the first to summarize and evaluate the relationship between exposure to cooking fumes and the risk of LCINS.

METHODS

This study conducted an online literature search of PubMed, CINAHL, and PsychInfo databases. Inclusion criteria were original research articles published in English, that assessed the relationship between exposure to cooking fumes and the risk of lung cancer between 1 January 2012 and 6 December 2022, and that included never-smokers.

RESULTS

Thirteen case-control studies and three prospective cohort studies, focusing mostly on women with LCINS, met the inclusion criteria. Seven case-control studies reported an association between exposure to cooking oil fumes and an increased risk of LCINS. Two case-control studies found that using a fume extractor was associated with a decreased risk of LCINS. In other case-control studies, coal use was linked to an increased risk of LCINS, and participants who did not use a ventilator in their kitchens had a higher risk for LCINS. Poor ventilation [Adjusted Hazard Ratio (AHR) = 1.49; 95% CI: 1.15, 1.95] and poor ventilation in combination with coal use (AHR = 2.03; 95% CI: 1.35, 3.05) were associated with an increased risk for LCINS in one prospective cohort study.

CONCLUSION

The evidence reviewed underscores the need to develop culturally-tailored interventions that improve access to affordable and clean fuel through engaging relevant stakeholders.

Preventive and therapeutic effects of green tea on lung cancer: a narrative review of evidence from clinical and basic research

Background and Objective

Green tea is a popular beverage worldwide and has numerous health-promoting properties. Accumulating evidence indicates that green tea has preventive and therapeutic effects on lung cancer. This study aimed to investigate the association between green tea consumption and lung cancer.

Methods

We performed a narrative review to summarized the association between green tea consumption and lung cancer.

Key Content and Findings

Green tea consumption is known to decrease lung cancer risk in the general population, as indicated by meta-analyses of observational studies. Two active components of green tea, theabrownin and (-)-epigallocatechin gallate (EGCG), mediate the antitumor activity of green tea. Theabrownin promotes apoptosis, induces cell cycle arrest, and inhibits the migration, clone formation, and proliferation of lung cancer cell lines in vitro and in vivo. EGCG inhibits lung cancer cell proliferation and promotes apoptosis, agenesis, and epithelial-mesenchymal transition (EMT). In addition, EGCG sensitizes lung cancer cells to cisplatin and tyrosine kinase inhibitors (TKIs). The possible molecular mechanisms underlying the antitumor activity of EGCG and theabrownin were reviewed.

Conclusions

Observational studies have indicated that green tea has preventive effects on lung cancer. In vitro and animal studies have indicated that green tea has therapeutic effects on lung cancer. Further clinical trials are needed to illustrate the therapeutic effects of green tea or its active components (i.e., theabrownin, EGCG) on lung cancer.

Derivation and validation of a prediction model for patients with lung nodules malignancy regardless of mediastinal/hilar lymphadenopathy

BACKGROUND

Clinical prediction models to classify lung nodules often exclude patients with mediastinal/hilar lymphadenopathy, although the presence of mediastinal/hilar lymphadenopathy does not always indicate malignancy. Herein, we developed and validated a multimodal prediction model for lung nodules in which patients with mediastinal/hilar lymphadenopathy were included.

METHODS

A single-center retrospective study was conducted. We developed and validated a logistic regression model including patients with mediastinal/hilar lymphadenopathy. Discrimination of the model was assessed by area under the operating curve. Goodness of fit test was performed via the Hosmer-Lemeshow test, and a nomogram of the logistic regression model was drawn.

RESULTS

There were 311 cases included in the final analysis. A logistic regression model was developed and validated. There were nine independent variables included in the model. The aera under the curve (AUC) of the validation set was 0.91 (95% confidence interval [CI]: 0.85-0.98). In the validation set with mediastinal/hilar lymphadenopathy, the AUC was 0.95 (95% CI: 0.90-0.99). The goodness-of-fit test was 0.22.

CONCLUSIONS

We developed and validated a multimodal risk prediction model for lung nodules with excellent discrimination and calibration, regardless of mediastinal/hilar lymphadenopathy. This broadens the application of lung nodule prediction models. Furthermore, mediastinal/hilar lymphadenopathy added value for predicting lung nodule malignancy in clinical practice.

Sleep duration, chronotype, and insomnia and the risk of lung cancer: United Kingdom Biobank Cohort

BACKGROUND

Relationships between sleep duration, chronotype, insomnia and lung cancer risk have not been comprehensively examined. Inter-relations between sleep traits on the risk of lung cancer have not been assessed. We aimed to examine sleep traits with lung cancer risk.

METHODS

Participants were recruited between 2006 - 2010 and followed through November 30th, 2020. We included 382,966 participants (3,664 incident lung cancer) in analysis. Cox proportional hazards models estimated hazards ratios (HR) and 95% confidence intervals (CI) for associations between sleep duration, chronotype, and insomnia symptoms and lung cancer risk. Joint effects analyses were examined between sleep duration and three traits (chronotype,insomnia,daytime napping). Non-linear associations between sleep duration and lung cancer risk were assessed in restricted cubic spline analysis.

RESULTS

Longer sleep (>8 hours) was positively associated with lung cancer risk compared with normal sleep duration (7-8 hours; HR=1.22; 95% CI: 1.10, 1.36). Frequent insomnia symptoms increased the risk of lung cancer compared with never/rarely experiencing symptoms (HR= 1.16; 95% CI: 1.05, 1.28). Joint effects between sleep duration and chronotype, and sleep duration and insomnia symptoms were observed. In analysis excluding participants reporting shift work at baseline, evening chronotypes ('slight', 'definite') were at a greater risk of lung cancer compared with definite morning chronotype (HR=1.17; 95% CI: 1.06, 1.28 and HR=1.37; 95% CI: 1.21, 1.54, respectively).

CONCLUSIONS

Sleep traits such as long sleep duration, frequent insomnia symptoms, and definite evening chronotype may be risk factors for lung cancer. Joint effects should be further investigated.

IMPACT

Sleep traits may be risk factors of lung cancer.

Fruits and Vegetables and Lung Cancer Risk in Never Smokers. A Multicentric and Pooled Case-Control Study

BACKGROUND

The etiology of lung cancer in never smokers is partly unknown. We aimed to assess the effect of fruits and vegetables consumption on lung cancer risk in never smokers.

METHODS

We pooled five multicenter case-control studies performed in Northwestern Spain. Cases and controls were all never smokers. All lung cancer cases had anatomopathological confirmed diagnoses. We performed a multivariate logistic regression to analyze the effect of different types of fruits and vegetables consumption on lung cancer risk.

RESULTS

A total of 438 cases and 781 controls were included. We observed that a consumption from one to six times per week shows a negative association with lung cancer risk for: kiwis (OR 0.67; 95%CI 0.46-0.95), oranges (OR 0.55; 95%CI 0.37-0.80), turnip tops (OR 0.48; 95%CI 0.34-0.66), "berza gallega" (OR 0.70; 95%CI 0.51-0.97) and broccoli (OR 0.55; 95%CI 0.35-0.83) compared to less than once a week consumption. On the other hand, we found an increased risk for lung cancer with a daily consumption of tomatoes, carrots and potatoes.

CONCLUSIONS

Oranges, kiwis, turnip tops, berza gallega and broccoli may play a protective role on lung cancer development in never smokers while tomatoes, carrots and potatoes might have some association with this disease.

An Overview of Lung Cancer in Women and the Impact of Estrogen in Lung Carcinogenesis and Lung Cancer Treatment

Lung cancer incidence and mortality have significantly increased in women worldwide. Lung adenocarcinoma is the most common form of lung cancer globally. This type of lung cancer shows differences by sex, including the mutational burden, behavior, clinical characteristics, and response to treatment. The effect of sex on lung cancer patients' survival is still controversial; however, lung adenocarcinoma is considered a different disease in women and men. Moreover, lung adenocarcinoma is strongly influenced by estrogen and is also different depending on the hormonal status of the patient. Young pre-menopausal women have been explored as an independent group. They presented in more advanced stages at diagnosis, exhibited more aggressive tumors, and showed poor survival compared to men and post-menopausal women, supporting the role of sex hormones in this pathology. Several reports indicate the estrogen's role in lung carcinogenesis and tumor progression. Thus, there are currently some clinical trials testing the efficacy of antihormonal therapy in lung cancer treatment. This mini review shows the updated data about lung cancer in women, its characteristics, the etiological factors that influence carcinogenesis, and the critical role of estrogen in lung cancer and treatment.

Epidemiology and prognosis in young lung cancer patients aged under 45 years old in northern China

To explore the epidemiological characteristics and prognosis of lung cancer in patients aged under 45 years old in northern China. The population-based database about lung cancer cases aged under 45y selected form the Hebei Provincial Cancer Registry Center from 2010-2015. Mortality data of young death from 1973 to 1975, 1990 to 1992, and 2004 to 2005 were extracted from the national retrospective survey of death. Mortality rates were calculated by the mortality database above in this analysis. Consecutive, 954 non-selected younger patients (< 45 years) and 2261 selected older patients (≥ 45 years) with pathologically diagnosed lung cancer treated at the Fourth Hospital of Hebei Medical University were included as the hospital-based database. Epidemiological, treatment outcomes and prognosis status from 2010 to 2017 were documented. A comparison with younger and older patients was also made. Multivariate analysis with young lung cancer patients was calculated by Cox regression model. The younger lung cancer mortality rate tended to slightly increase in Hebei Province, from 1.04 per100 000 in 1973 to 2.01 per 100 000 in 2015, but the PDR tended to decrease over the last 40 years. There were 954 younger and 2261 older lung cancer patients included in the hospital-based database. The proportions of patients who were female (50.84% vs 34.85%), family history of cancer (12.37% vs 6.32%), advanced stage at diagnosis (65.46% vs 60.77%) and adenocarcinoma (65.27% vs 61.11%) were relatively higher in the younger group than in the older group. The median OS were 23.0 months and 27.0 months between younger and older, the OS difference existed between the two groups (P = 0.001). In the younger patients, Cox regression showed that a family history of cancer, symptoms at diagnosis, pathology, stage at diagnosis and surgery were confirmed as independent factors affecting the prognosis. Mortality rates among younger lung cancer patients showed an increasing trend in northern China. The younger account for small but have unique characteristics, with higher proportions of female, family history of cancer, adenocarcinoma and advanced stages than the older group and had a trend of worse OS.

Risk of two common glandular cell-type cancers (breast and colorectal cancers) in Chinese occupational chefs: a nationwide ecological study in Taiwan

OBJECTIVES

Cooking oil fumes (COFs) contain many carcinogens. We investigated the association between COFs and incidence risk of colorectal cancer and female breast in chefs.

METHODS

We identified Chinese food chefs and non-Chinese food chefs from Taiwan's national database of certified chefs in 1984-2007. In total, 379,275 overall and 259,450 females had not been diagnosed as having any cancer before chef certification. We followed these chefs in Taiwan's Cancer Registry Database (1979-2010) and Taiwan's National Death Statistics Database (1985-2011) for newly diagnosed colorectal cancer and female breast cancer.

RESULTS

A total of 4,218,135 and 2,873,515 person-years were included in our analysis of colorectal cancer and female breast cancer incidence, respectively. Compared to non-Chinese food chefs, the Chinese food chefs had an adjusted IRR for colorectal cancer of 1.65 (95% CI  1.17-2.33). The risk of colorectal cancer was even higher among female Chinese food chefs certified for more than 5 years (adjusted incident rate ratio (IRR) = 2.39, 95% CI   1.38-4.12). For female breast cancer, the risk was also significant (adjusted IRR = 1.40, 95% CI 1.10-1.78) and the risks were even higher in female Chinese food chefs certified for more than 5 years (adjusted IRR = 1.74, 95% CI 1.37-2.22).

CONCLUSIONS

This study found that Chinese food chefs had an increased risk of colorectal cancer and female breast cancer, particularly female chefs who had worked for more than 5 years. Future human and animal studies are necessary to re-confirm these findings.

Increased Levels of Serum Glycosylated Hemoglobin are Associated with Depressive Symptoms in a Population with Cancer (≥49 Years): An Antidepressant-Stratified Analysis

Purpose

Patients with cancer tend to have a high prevalence of depressive symptoms. The direct relationship between serum glycosylated hemoglobin (GHb) levels and depressive symptoms in cancer patients is still uncertain. We aimed to evaluate the association with serum GHb levels with depressive symptoms in the population (aged ≥49 years) with cancer.

Patients and Methods

Longitudinal data in 204 participants with cancer obtained from The Irish LongituDinal Study on Ageing (TILDA) were used to investigate the association of serum GHb levels with depressive symptoms.

Results

Our results suggested a positive and significant association between serum GHb levels and depression score, independent of age, gender, body mass index (BMI), currently married, education, smoking status, drink alcohol, systolic and diastolic blood pressure (BP), physical activity, self-reported cardiovascular diseases and laboratory measurement in participants with cancer (coefficient =0.141, P<0.001; Model 2) at baseline (wave 1). Higher GHb levels did associate with higher prevalence of depressive symptoms in participants with cancer (OR=2.100, 95% CI 1.105–5.036, P=0.004; Model 2) after adjustment for these same confounding factors in wave 1 was made. Stratified analysis further showed that these significant associations were interfered by antidepressants. Sensitivity analysis showed that higher serum GHb levels in subjects with cancer were linked to higher prevalence of depression events during a follow-up of 4 years.

Conclusion

Our results found a significant association between elevated serum GHb levels and increased risk of depressive symptoms in the population aged ≥49 years with cancer after confounding factors were adjusted.

Exposure to PM2.5 is associated with malignant pleural effusion in lung cancer patients

Air pollution has been recognized to be a risk factor for lung cancer. The objective of this study was to investigate the effects of air pollution on heavy metal alterations in the pleural effusion of lung cancer patients. Pleural effusion was collected from patients with lung cancer and congestive heart failure (CHF). One-year average levels of particulate matter with an aerodynamic diameter of < 10 µm (PM₁₀), PM_2.5, NO₂, and SO₂ were linked to the exposure of these subjects. Traffic-related metals, included Al, Fe, Cu, Zn, and Pb, were determined in the pleural effusion. Logistic regression models were used to examine their associations. There were 63 lung cancer patients and 31 CHF patients enrolled in the current study. We found that PM₁₀, PM_2.5, and NO₂ were negatively correlated with Al in the pleural effusion, whereas PM_2.5 was positively correlated with Zn in the pleural effusion. Increases in 1 μg/m³ of PM_2.5 and 1 ng/mL of Zn were associated with lung cancer (adjusted OR=2.394, 95% CI= 1.446-3.964 for PM_2.5; adjusted OR=1.003, 95% CI=1.000-1.005 for Zn). Increases in PM_2.5 and Zn in the pleural effusion increased the risk of malignant pleural effusion in lung cancer patients (adjusted OR=1.517; 95% CI=1.082-2.127 for PM_2.5; adjusted OR=1.002, 95% CI=1.000-1.005 for Zn). Furthermore, we observed that adenocarcinomas increased in association with a 1-μg/m³ increase in PM_2.5 (crude OR=1.683; 95% CI=1.006-2.817) in lung cancer patients. In conclusion, PM_2.5 exposure and the possible resultant Zn in the pleural effusion associated with the development of malignant pleural effusion in lung cancer.