Cáncer de pulmón microcítico. Metodología y resultados preliminares del estudio SMALL CELL

Issue 2 - "Update on adverse respiratory effects of indoor air pollution" Part 1): Indoor air pollution and respiratory diseases: A general update and a Portuguese perspective

OBJECTIVE

To quantify the impact of different air pollutants on respiratory health based on robust estimates based on international data and to summarise the evidence of associations between indoor exposure to those pollutants and respiratory morbidity in the Portuguese population.

RESULTS

Several systematic reviews and meta-analyses (MA) at the world level demonstrate the impact of indoor air quality on respiratory health, with indoor particulate matter and gasses exerting a significant effect on the airways. Volatile organic compounds (VOC) have been related to asthma and lung cancer. However, only meta-analyses on biomass use allowed documentation of long-term respiratory effects. While early publications concerning Portuguese-based populations mainly focused on indoor exposure to environmental tobacco smoke, later studies relocated the attention to relevant exposure environments, such as day care buildings, schools, residences and nursing homes. Looking at the pooled effects from the reviewed studies, high levels of carbon dioxide and particulate matter in Portuguese buildings were significantly associated with asthma and wheezing, with VOC and fungi showing a similar effect in some instances.

CONCLUSIONS

Despite the significant reduction of indoor air pollution effects after the 2008 indoor smoking prohibition in public buildings, studies show that several indoor air parameters are still significantly associated with respiratory health in Portugal. The country shares the worldwide necessity of standardisation of methods and contextual data to increase the reach of epidemiological studies on household air pollution, allowing a weighted evaluation of interventions and policies focused on reducing the associated respiratory morbidity.

Social determinants of health and lung cancer surgery: a qualitative study

Introduction

Social determinants of health (SDOH) are non-clinical factors that may affect the outcomes of cancer patients. The purpose of this study was to describe the influence of SDOH factors on quality of life (QOL)-related outcomes for lung cancer surgery patients.

Methods

Thirteen patients enrolled in a randomized trial of a dyadic self-management intervention were invited and agreed to participate in semi-structured key informant interviews at study completion (3 months post-discharge). A conventional content analysis approach was used to identify codes and themes that were derived from the interviews. Independent investigators coded the qualitative data, which were subsequently confirmed by a second group of independent investigators. Themes were finalized, and discrepancies were reviewed and resolved.

Results

Six themes, each with several subthemes, emerged. Overall, most participants were knowledgeable about the concept of SDOH and perceived that provider awareness of SDOH information was important for the delivery of comprehensive care in surgery. Some participants described financial challenges during treatment that were exacerbated by their cancer diagnosis and resulted in stress and poor QOL. The perceived impact of education varied and included its importance in navigating the healthcare system, decision-making on health behaviors, and more economic mobility opportunities. Some participants experienced barriers to accessing healthcare due to insurance coverage, travel burden, and the fear of losing quality insurance coverage due to retirement. Neighborhood and built environment factors such as safety, air quality, access to green space, and other environmental factors were perceived as important to QOL. Social support through families/friends and spiritual/religious communities was perceived as important to postoperative recovery.

Discussion

Among lung cancer surgery patients, SDOH factors can impact QOL and the patient's survivorship journey. Importantly, SDOH should be assessed routinely to identify patients with unmet needs across the five domains. SDOH-driven interventions are needed to address these unmet needs and to improve the QOL and quality of care for lung cancer surgery patients.

Small-cell lung cancer in never-smokers

Background

Lung cancer is a public health problem worldwide. Small-cell lung cancer (SCLC) is the most aggressive histologic type, with a 5-year survival <10%. SCLC is closely associated with tobacco consumption and infrequent in never-smokers. We aim to describe SCLC characteristics in never-smokers recruited in a radon-prone area.

Patients and methods

We designed a multicentric case series where SCLC cases were recruited consecutively following histologic confirmation. Detailed information was obtained for indoor radon exposure, occupation and environmental tobacco smoke. We also collected different clinical characteristics such as extended or limited disease at diagnosis.

Results

We recruited 32 never-smoking SCLC cases. Median age was 75 years and 87.5% were women; 47% had extended disease. Median radon concentration was 182 Bq/m³. There were no statistically significant differences in residential radon concentration neither regarding age at diagnosis nor regarding sex. The most frequent symptoms were constitutional syndrome (23.1%) and coughing (23.1%). As much as 63% of cases had an Eastern Cooperative Oncology Group Study (ECOG) status of 0-2. The 1- and 2-year survival rates were 34.4% and 21.9%, respectively. The 2-year survival rate with a localized tumor was 26.7%, compared with 18.8% for extended disease.

Conclusions

These results show, for the first time, that indoor radon might not be associated with SCLC characteristics at diagnosis in never-smokers, and also confirms the low survival of this aggressive type of lung cancer also for never-smokers.

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Small-cell lung cancer in never-smokers is an infrequent disease.

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Risk factors are poorly characterized, and we have observed that residential radon may have a role (182 Bq/m³ as average).

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In this study, 1- and 2-year survival rates were 34.4% and 21.9%, respectively.

Residential Radon and Small Cell Lung Cancer. Final Results of the Small Cell Study

INTRODUCTION

Residential radon is considered the second cause of lung cancer and the first in never smokers. Nevertheless, there is little information regarding the association between elevated radon levels and small cell lung cancer (SCLC). We aimed to assess the effect of residential radon exposure on the risk of SCLC in general population through a multicentric case-control study.

METHODS

A multicentric hospital-based case-control study was designed including 9 hospitals from Spain and Portugal, mostly including radon-prone areas. Indoor radon was measured using Solid State Nuclear Track Detectors at the Galician Radon Laboratory.

RESULTS

A total of 375 cases and 902 controls were included, with 24.5% of cases being women. The median number of years living in the measured dwelling was higher than 25 years for both cases and controls. There was a statistically significant association for those exposed to concentrations higher than the EPA action level of 148Bq/m3, with an Odds Ratio of 2.08 (95%CI: 1.03-4.39) compared to those exposed to concentrations lower than 50Bq/m3. When using a dose-response model with 100Bq/m3 as a reference, it can be observed a linear effect for small cell lung cancer risk. Smokers exposed to higher radon concentrations pose a much higher risk of SCLC compared to smokers exposed to lower indoor radon concentrations.

CONCLUSIONS

Radon exposure seems to increase the risk of small cell lung cancer with a linear dose-response pattern. Tobacco consumption may also produce an important effect modification for radon exposure.

Residential radon and small cell lung cancer. A systematic review

Residential radon exposure is considered the second cause of lung cancer and the first in never smokers. Nevertheless, the association between the different histological types of lung cancer and radon is not completely clear, and radon effect on small cell lung cancer is not completely understood. We aim to asses the effect of residential radon exposure on the risk of small cell lung cancer (SCLC) in general population and miners through a systematic review applying predefined inclusion and exclusion criteria. 16 studies were included. Most of them point to a relationship between indoor radon and SCLC, though some investigations show no association. When comparing the risk of SCLC due to radon exposure with NSCLC, it can be observed that an increased risk for SCLC is present. Small cell lung cancer seems to be the histological type of lung cancer most tightly related with residential radon.