**Acknowledgements**

confirm diagnostic as predict a patient's response to certain cancer therapies or determine

These results obtained via biomarkers in blood and sputum were quite promising in elucidat‐ ing risk to LC, especially when the biomarkers studied are non invasive and inexpensive assays and could be an effective methods also to monitor the biological effects of environmental and

Additionally, we presented evidences that showed that AFB is more sensitive than WLB to detect early lesions, thereby allowing their localisation for biopsy or interventional procedures.

Is well known that resolution of CT scan and other images technologies improves each year, allowing to detect more nodules, but not necessarily LC in early stages. Additionally, is well known the high frequency of lung nodules with undetermined significance and that LC often causes no symptoms until it is spread outside the lung. From this point of view, non invasive biomarkers and AFB might contribute as a first step in detecting pre- neoplastic a pre- invasive lesions. Screening in people with high LC risk including those with smoking habit and or nodules non necessary cancerous, might means a higher survival and improve the life quality. The screening in people with high risk of LC might be a good preventive way to improve the survival to 5 years, especially when different studies have shown an important association

Genetic differences in metabolic activation and detoxification of environmental carcinogen, like PAHs and or As, may partially explain host susceptibility to chemically induced cancers

Adonis et al (2005) showed the association of combined genotypes of cytochrome CYP1A1 (Msp1) and glutathione-S-transferase GSTM1 and lung cancer risk, for a population histori‐ cally exposed to As in the Antofagasta region. This study showed in the healthy group, a CYP1A1 \*2A allele frequency for MspI of 0.41, whereas for lung cancer group 0.46. No statically significant difference was observed between the healthy group and lung cancer group (*p* = 0.437, CI =−0.224 to 0.124). However, the CYP1A1 \*2A genotype was associated with an increased relative lung cancer risk O.R. = 2.08 (95% CI = 1.04–4.03, *p* = 0.04). In addition, 35% of healthy group and 39% of the lung cancer group were homozygote for the null variant allele of GSTM1. For men the CYP1A1 \*2A genotype was associated with a highly significant estimated relative lung cancer risk O.R. = 2.60 (95% CI = 1.07–5.94, *p* = 0.0334). The relative lung cancer risk for the total sample with the CYP1A1 \*2A/null GSTM1 genotype was 2.51 (O.R. = 2.51, CI = 1.07–5.40, *p* = 0.0322), which one increased when the sample was stratified by smoking

These results suggest that patients with previous history of iAs exposure as the Antofagasta population, and with smoking habit might be have an additional factor related to genetic susceptibility to lung cancer. The cancer mortality rate in region II for iAs- associated cancers, as lung cancer, at least might be partly related to differences in As biotransformation. Indi‐ viduals with the CYP1A1\*2A and/or the combined CYP1A1\*2A and GSTM1 null genotype might have a greater capacity to metabolically active PAHs and lower capacity to conjugate

Then the association of WLB and AFB would increase the sensitivity to detect PNL.

between genetic host characteristics and exposure to environmental carcinogens.

(Daly et al., 1994; London et al, 2000, Kang et al, 2012).

habit (O.R. = 2.98, CI = 1.10–7.10, *p* = 0.0497) (Adonis et al, 2005).

whether cancer has returned.

70 Oncogenesis, Inflammatory and Parasitic Tropical Diseases of the Lung

occupational carcinogens.

This work was supported by Grants from INNOVA-CORFO Chile (07CN13PBT-48 and 11IDL2-10634, 2012). We also thank all the volunteers that accepted to participate in this project and to the permanent support of the Canada Embassy in Chile. The authors also thank Dr. Stephen Lam for his invaluable support, advise and helpful discussions. This work has been carried out with ethical committee approval of the Faculty of Medicine of University of Chile.
