Women Epidemiology Lung Cancer (WELCA) study: reproductive, hormonal, occupational risk factors and biobank

Lung cancer risk associated with occupations in women: a pooling study

BACKGROUND

Occupation is an important risk factor for lung cancer. This knowledge is mainly based on studies conducted on men, with the results being generalized to women.

AIMS

We aimed to identify the relationship between different occupations and lung cancer in women.

METHODS

Pooling study in which data were pooled from six case-control studies conducted at 13 Spanish hospitals and 1 hospital in Portugal. Each woman's longest held job was coded as per the ISCO-08. Results were adjusted for age, smoking, and exposure to residential radon.

RESULTS

The study population comprised 1262 women: 618 cases and 644 controls. The reference group were white-collar workers. The adjusted multivariate analysis showed a higher risk of developing lung cancer among teaching professionals (odds ratio [OR]: 4.36; 95% confidence interval [CI] 1.73-11.02), cooks (OR: 3.59; 95% CI 1.52-8.48), domestic cleaners and helpers (OR: 2.98; 95% CI 1.54-5.78), homemakers (OR: 2.30; 95% CI 1.26-4.21) and crop farmers, livestock farmers and gardeners (OR: 2.06, 95% CI: 1.11-3.81). For adenocarcinoma, the highest risk was observed in teaching professionals, and for small-cell carcinoma, the highest risk was observed in cooks. Higher risks were observed for small-cell carcinoma compared to other histological types.

CONCLUSIONS

Some occupations may be associated with an increased risk of lung cancer in women and this risk could vary by histologic subtype; however, further research is needed to confirm these associations. In any case, protection measures must be implemented in the workplace aimed at reducing the risk of lung cancer among women workers, and more studies exclusively focused on women are warranted.

Narrative review of occupational exposures and noncommunicable diseases

OBJECTIVE

Within the scope of the Exposome Project for Health and Occupational Research on applying the exposome concept to working life health, we aimed to provide a broad overview of the status of knowledge on occupational exposures and associated health effects across multiple noncommunicable diseases (NCDs) to help inform research priorities.

METHODS

We conducted a narrative review of occupational risk factors that can be considered to have "consistent evidence for an association," or where there is "limited/inadequate evidence for an association" for 6 NCD groups: nonmalignant respiratory diseases; neurodegenerative diseases; cardiovascular/metabolic diseases; mental disorders; musculoskeletal diseases; and cancer. The assessment was done in expert sessions, primarily based on systematic reviews, supplemented with narrative reviews, reports, and original studies. Subsequently, knowledge gaps were identified, e.g. based on missing information on exposure-response relationships, gender differences, critical time-windows, interactions, and inadequate study quality.

RESULTS

We identified over 200 occupational exposures with consistent or limited/inadequate evidence for associations with one or more of 60+ NCDs. Various exposures were identified as possible risk factors for multiple outcomes. Examples are diesel engine exhaust and cadmium, with consistent evidence for lung cancer, but limited/inadequate evidence for other cancer sites, respiratory, neurodegenerative, and cardiovascular diseases. Other examples are physically heavy work, shift work, and decision latitude/job control. For associations with limited/inadequate evidence, new studies are needed to confirm the association. For risk factors with consistent evidence, improvements in study design, exposure assessment, and case definition could lead to a better understanding of the association and help inform health-based threshold levels.

CONCLUSIONS

By providing an overview of knowledge gaps in the associations between occupational exposures and their health effects, our narrative review will help setting priorities in occupational health research. Future epidemiological studies should prioritize to include large sample sizes, assess exposures prior to disease onset, and quantify exposures. Potential sources of biases and confounding need to be identified and accounted for in both original studies and systematic reviews.

Sleep Traits, Night Shift Work and Lung Cancer Risk among Women: Results from a Population-Based Case-Control Study in France (The WELCA Study)

Circadian rhythm disruption due to night shift work and/or sleep disorders is associated with negative health outcomes including cancer. There is only scant evidence of an association with lung cancer, unlike breast and prostate cancer. We explore the role of sleep disorders and night shift work in lung cancer risk among women in a population-based case-control study, including 716 lung cancer cases and 758 controls. Multivariable logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) associated with sleep duration per day (<7 h, 7−7.9 h, ≥8 h), a summary index of sleep disorders, chronotype, and night shift work exposure metrics. When compared to women with an average sleep duration of 7−7.9 h per day, the OR was 1.39 (95% CI 1.04−1.86) in long sleepers (≥8 h) and 1.16 (95% CI 0.86−1.56) in short sleepers (<7 h). Overall, lung cancer was not associated with the sleep disorder index, nor with night shift work, regardless of the duration of night work or the frequency of night shifts. However, elevated OR associated with the sleep disorder index were found in the subgroup of current smokers. The U-shaped association of lung cancer with sleep duration was more particularly pronounced among women who worked at night ≥5 years. Our findings suggested that sleep patterns are associated with lung cancer risk in women with a potential modifying effect by night shift work duration or tobacco smoking.

Evaluating risk factors for lung cancer among never-smoking individuals using two Australian studies

PURPOSE

Lung cancer (LC) in never-smoking individuals would rank as Australia's eighth most deadly cancer, yet risk factors remain uncertain. We investigated demographic, lifestyle and health-related exposures for LC among never-smoking Australians.

METHODS

Using the prospective 45 and Up Study with 267,153 New South Wales (NSW) residents aged ≥ 45 years at recruitment (2006-2009), we quantified the relationship of 20 potential exposures with LC among cancer-free participants at baseline who self-reported never smoking. Adjusted hazard ratios (HR) and 95% confidence intervals (CI) for incident LC were estimated using Cox regression. The NSW Cancer, Lifestyle and Evaluation of Risk (CLEAR) Study, a case-control study including 10,781 NSW residents aged ≥ 18 years (2006-2014), was used to examine 16 potential LC exposures among cancer-free never-smoking participants. Adjusted odds ratios (OR) and 95% CI of LC were estimated using logistic regression.

RESULTS

There were 226 LC cases among 132,354 cancer-free 45 and Up Study participants who reported never smoking, with a median follow-up of 5.41 years. The CLEAR Study had 58 LC cases and 1316 cancer-free controls who had never smoked. Analyses of both datasets showed that Asian-born participants had a higher risk of LC than those born elsewhere: cohort, adjusted HR = 2.83 (95% CI 1.64-4.89) and case-control, adjusted OR = 3.78 (1.19-12.05). No significant association with LC was found for other exposures.

CONCLUSION

Our findings support the growing evidence that never-smoking, Asian-born individuals are at higher risk of developing LC than those born elsewhere. Ethnicity could be considered when assessing potential LC risk among never-smoking individuals.

Risk of lung cancer among women in relation to lifetime history of tobacco smoking: a population-based case-control study in France (the WELCA study)

Background

This study aims to provide new insights on the role of smoking patterns and cigarette dependence in female lung cancer, and to examine differences by histological subtype.

Methods

We conducted a population-based case-control study in the great Paris area among women including 716 incident cases diagnosed between 2014 and 2017 and 757 age-matched controls. Detailed data on smoking history was collected during in-person interviews to assess intensity and duration of tobacco smoking, time since cessation, smoking habits (depth of smoke inhalation, use of filter, type of tobacco, and type of cigarettes) and Fagerström test for cigarette dependence. The comprehensive smoking index (CSI), a score modelling the combined effects of intensity, duration and time since quitting smoking was determined for each subject. Multivariable logistic regression models were fitted to calculate odds ratios (ORs) and their confidence intervals (95%CI) of lung cancer associated with smoking variables.

Results

Lung cancer risk increased linearly with intensity and duration of tobacco smoking while it decreased with time since cessation, to reach the risk in never-smokers after 20 years of abstinence. The combined effect of intensity and duration of tobacco smoking was more than multiplicative (p-interaction 0.012). The OR in the highest vs the lowest quartile of CSI was 12.64 (95%CI 8.50; 18.80) (p-trend < 0.001). The risk of small cell or squamous cell carcinomas increased with the CSI more sharply than the risk of adenocarcinomas. Deep smoke inhalation, dark vs blond tobacco, conventional vs light cigarettes, and unfiltered vs filtered cigarettes, as well as having mixed smoking habits, were found to be independent risk factors. Having high cigarette addiction behaviours also increased the risk after adjusting for CSI.

Conclusion

This study provides additional insights on the effects of tobacco smoking patterns on lung cancer risk among women.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08433-z.

Gender-specific aspects of epidemiology, molecular genetics and outcome: lung cancer

Lung cancer remains the leading cause of cancer-related deaths worldwide in women and men. In incidence, lung cancer ranks second, surpassed by breast cancer in women and prostate cancer in men. However, the historical differences in mortality and incidence rate between both sexes have changed in the last years. In the last decades, we have also witnessed an increased number of lung cancer in female never-smokers. These disparities have grown our interest in studying the impact of the gender and sex in the presentation of lung cancer. The aetiology is yet to be fully elucidated, but the data are clear so far: there is a growing divide between lung cancer presentation in women and men that will change our management and study of lung cancer. This article aims to review the sex and gender differences in lung cancer.

Biochemically Tracked Variability of Blood Plasma Thawed-State Exposure Times in a Multisite Collection Study

The integrity of blood plasma/serum (P/S) specimens can be impacted by preanalytical handling and storage conditions that result in thawed-state exposures (> -30°C). We recently reported a simple dilute-and-shoot, intact-protein liquid chromatography/mass spectrometry (LC/MS) assay called ΔS-Cys-Albumin that quantifies cumulative exposure of P/S to thawed conditions based on the change in relative abundance of the oxidized (S-cysteinylated) proteoform of albumin (S-Cys-Albumin) in the native sample to that of an aliquot of the sample intentionally driven to its maximum oxidation state. Herein, we evaluated the effect of prestorage delay and initial storage temperature on sample integrity by applying the ΔS-Cys-Albumin assay to a set of plasma samples (n = 413) collected under a single clinical study but from 12 different collection sites. Major differences (p < 0.0001) were observed between different groups of samples with modestly inconsistent initial handling conditions (i.e., initial processing of whole blood to plasma and placement at -80°C completed in under 3 hours, 3-13 hours, and over 17 hours). ΔS-Cys-Albumin was significantly inversely correlated with delay time at 4°C before centrifugation and total delay before final storage at -80°C (p < 0.0001). Samples from two collection sites had much lower ΔS-Cys-Albumin values relative to samples from other sites, in accordance with the fact that they were stored at -20°C for an average of 7.6 months before shipment to the central repository for final storage at -80°C. Based on the rate law for S-Cys-Albumin formation in plasma ex vivo, the average time that each plasma specimen had been exposed to the equivalent of room temperature (23°C) was back calculated from the measured ΔS-Cys-Albumin values. A survey of clinical analytes in P/S whose measured concentrations are sensitive to the initial handling/storage conditions documented in this study is provided and the ramifications of the plasma integrity findings from this multisite clinical study are discussed.

Diagnostic and Prognostic Performance of Blood Plasma Glycan Features in the Women Epidemiology Lung Cancer (WELCA) Study

Lung cancer is the leading cause of cancer death in women living in the United States, which accounts for approximately the same percentage of cancer deaths in women as breast, ovary, and uterine cancers combined. Targeted blood plasma glycomics represents a promising source of noninvasive diagnostic and prognostic biomarkers for lung cancer. Here, 208 samples from lung cancer patients and 207 age-matched controls enrolled in the Women Epidemiology Lung Cancer (WELCA) study were analyzed by a bottom-up glycan "node" analysis approach. Glycan features, quantified as single analytical signals, including 2-linked mannose, α2-6 sialylation, β1-4 branching, β1-6 branching, 4-linked GlcNAc, and antennary fucosylation, exhibited abilities to distinguish cases from controls (ROC AUCs: 0.68-0.92) and predict survival in patients (hazard ratios: 1.99-2.75) at all stages. Notable alterations of glycan features were observed in stages I-II. Diagnostic and prognostic glycan features were mostly independent of smoking status, age, gender, and histological subtypes of lung cancer.