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Background and objective Lung cancer rates among women in rural Xuanwei and Fuyuan counties in eastern Yunnan province, China, are among the highest in the world, even though almost all women are non-smokers, and they tend to develop lung cancer at a younger age than other locations by roughly 5 yr-10 yr. This study investigated the survival of lung cancer patients among female never-smokers. Methods The female never-smokers, who had lived for many years in Xuanwei and Fuyuan counties, with lung cancer newly-diagnosed between July 2006 to March 2010, were followed up through the end of 2016. Age-standardized relative survival for all cases was calculated using local life table. The Kaplan-Meier method and Log-rank test were used to analyze the relationship between the variables and the prognosis in univariate analysis. Cox regression analysis was employed in the multivariate analysis. Results Among 1,250 total subjects, 1,075 died and the remaining 175 were censored during the follow-up, with a median follow-up period of 69 months (95%CI: 61.9-76.0). Overall, the mean age was (54.8 ±10.9) yr, with variable clinical stages: 3.5% of cases were stage I, 8.7% stage II, 20.7% stage III, 29.7% stage IV, and 37.4% stage unknown. The 645 patients(51.6%) with cyto-histological diagnosis contains 303 with Squamous cell carcinoma, and 231 with adenocarcinoma, 24 with small cell, 43 with other specified type and 39 with unknown histological type. Only 215 (17.2%) patients received surgery, 487 (39.0%) were treated without surgery, and 548 (43.8%) did not receive any specific anticancer therapy. The 5-year observed survival rate and age-standardized relative survival were 8.9% (95%CI: 7.0-10.6), and 10.1% (95%CI: 3.7-20.5) respectively, with a median survival of 13.2 months. The 5-year survival rates were 41.1% for stage I, 22.4% for stage II, 5.3% for stage III, 1.3% for stage IV, 11.2% for missing stage, 17.9% for adenocarcinoma, and 5.6% for squamous cell carcinoma respectively. Surgery significantly improved 5-year survival rate compared with non-surgery (34.8% vs 3.2%, P

Background and objective It has been proven that the lung cancer mortality rate in Xuanwei County, China was among the highest in the country and has been associated with exposure to indoor smoky coal emissions that contain high levels of polycyclic aromatic hydrocarbons. This risk may be modified by variation in genetic polymorphisms and coal subtypes. Our objective was to use molecular epidemiological techniques to investigate the relationship among genetic polymorphisms, coal subtype and lung cancer risk in Xuanwei County. Methods On the basis of two population-based case-control studies in residents of Xuanwei County, China, questionnaires covering demographic information, smoking history, family and personal medical history, and information on other variables were administered and buccal cells and sputum samples were collected separately from each subject enrolled to extract DNA. GST superfamily, AKR1C3 superfamily, OGG1 superfamily and other genotype were scanned by useing PCR method. ORs and 95%CIs were used to estimate the association between genotypes, coal subtypes and lung cancer risk factors by conditional Logistic regression using Statistical Analysis Software. Results Compared with subjects who using smokeless coal or wood, smoky coal use was statistically significantly associated with lung cancer risk (OR=7.7, 95%CI: 4.5-13.3). There was marked heterogeneity in risk estimates for specific subtypes of smoky coal. Estimates were highest for coal from the Laibin (OR=24.8), Longtan (OR=11.6) and Baoshan (OR=6.0) coal types, and lower for coal from other types; the risk within the same subtype of coal in male and female were similar. The GSTM1-null genotype, the AKR1C3 (Ex1-70C>G), OGG1 (Ex6-315C>G) genotypes were closely associated with increased risk of lung cancer in Xuanwei County, and their odds ratios (95%CI) were 2.3 (1.3-4.2), 1.8 (1.0-3.5) and 1.9 (1.1-3.3), respectively. Compared to subjects who with GSTM1-positive and used less than 130 tons of smoky coal during their lifetime, higher risks were closely associated with GSTM1-null and heavier users (≥130 tons), with the OR was 4.9 (95%CI: 1.3-18.2) and 2.7 (95%CI: 1.0-7.4) for female and male, respectively. However, higher risks were only found within female for AKR1C3 (Ex1-70C>G) and OGG1 (Ex6-315C>G), with OR (95%CI)=12.9 (2.2-107.8) and 5.7 (1.1-34.2), respectively. Conclusion Lung cancer risks varied among coal subtypes; however, risks were similar between men and women exposed to the same type of coal. The GSTM1-null genotype may enhance susceptibility to air pollution from indoor smoky coal combustion emissions. AKR1C3 and OGG1 genotypes were significantly associated with higher risk of lung cancer, especially among heavily exposed women.

Background and objective Xuanwei county is located at Late Permian coal-accumulating area in eastern Yunnan and western Guizhou, China. The lung cancer mortality rate in Xuanwei county is among the highest in China and has been attributed to exposure to indoor smoky coal emissions that contain very high levels of polycyclic aromatic hydrocarbons (PAHs). Recent years, the pollution and the higher mortality rate of lung cancer has been watched in the area around Xuanwei, and there is no report about whether the epidemic levels and the pathogen of lung cancer in other area of eastern Yunnan is similar to that in xuanwei. The aim of this study is to epidemic levels and cause of lung cancer in coal-producing area in the east of Yunnan province. Methods 382 study units (nature villages) were selected by stratified cluster random sampling from coalproducing area in eastern Yunnan province, China. The villagers who were aged 30-79 years with no history of lung cancer were enrolled. All the participants received an initial single-view posterior-anterior chest radiograph and administered a questionnaire survey (which involves the information of demography, household and fuel use, lifestyle, tobacco and occupational exposure history, family and personal medical history, etc. The subjects with a positive screen by chest x-ray underwent to have a computed tomography scan of the chest and biopsy examination. The confidence interval of the standardized rate ratio were adopted to evaluate the statistical significance of differences in different regions. Results 52,833 villagers were surveyed and screened with X-ray. 604 of them were suspicious lung cancer with an initial chest radiograph, 541 underwent CT scan (362 were diagnosed by CT and 109 were diagnosed by histology). The adjusted positive rates for lung cancer screening with CT is 763.08 per 100,000, the age-standardized rate (ASR) with the world standard population is 426.28 per 100,000 (95% confidence interval=381.51/10 per 100,000 to 471.05 per 100,000), 482.78 per 100,000 for man, 387.98 per 100,000 for woman, male-to-female (M:F) rate ratios is 1.24. The intensity of lung cancer had significant difference between different study units. The ASR for lung cancer screening from A, B, C to D areas decreased in turn, and the area A was the highest of all, which was 6.97 times higher than the lowest area D, and the ratio between male and female was increased gradually. The positive rate for lung cancer was related to the distribution of coal and in direct proportion to the amount of smoky coal burning, but not associated with smokeless coal combustion. There are above 80% residents who burned "smoky" coal in indoor firepits which generated very high levels of air pollution. Lung cancer mortality of family members has the same distribution to positive rates of lung cancer screening, and they are in proportion to each other. 85% men smoke 16.12 cigarettes per day, averagely. About 50% of them did the job like coking, mining coal and so forth. Smoking rate of woman is 1.37%, they always did housework such as cooking, raising pigs and so on. Though the smoking and occupational hazard factors were not the major reasons for women to get lung cancer, they were possible reasons for men. Conclusion In Xuanwei country of China, lung cancer was associated with exposure to smoky coal emissions and family susceptibility. Smoking, coking and mining were not the major risk factors lead to lung cancer for women.