Reid A, de Klerk N, Ambrosini G L, Olsen N, Pang S C, Berry G, Musk A W
Occupational & Environmental Epidemiology Group, School of Population Health, University of Western Australia, Crawley, WA 6009, Australia.
Occup Environ Med. 2005 Dec;62(12):885-9. doi: 10.1136/oem.2005.020834.
To determine if the presence of asbestosis is a prerequisite for lung cancer in subjects with known exposure to blue asbestos (crocidolite).
Former workers and residents of Wittenoom with known amounts of asbestos exposure (duration, intensity, and time since first exposure), current chest x ray and smoking information, participating in a cancer prevention programme (n = 1988) were studied. The first plain chest radiograph taken at the time of recruitment into the cancer prevention programme was examined for radiographic evidence of asbestosis according to the UICC (ILO) classification. Cox proportional hazards modelling was used to relate asbestosis, asbestos exposure, and lung cancer.
Between 1990 and 2002 there were 58 cases of lung cancer. Thirty six per cent of cases had radiographic evidence of asbestosis compared to 12% of study participants. Smoking status was the strongest predictor of lung cancer, with current smokers (OR = 26.5, 95% CI 3.5 to 198) having the greatest risk. Radiographic asbestosis (OR = 1.94, 95% CI 1.09 to 3.46) and asbestos exposure (OR = 1.21 per f/ml-year, 95% CI 1.02 to 1.42) were significantly associated with an increased risk of lung cancer. There was an increased risk of lung cancer with increasing exposure in those without asbestosis.
In this cohort of former workers and residents of Wittenoom, asbestosis is not a mandatory precursor for asbestos related lung cancer. These findings support the hypothesis that it is the asbestos fibres per se that cause lung cancer, which can develop with or without the presence of asbestosis.
确定在已知接触青石棉（温石棉）的人群中，石棉沉着病的存在是否是肺癌发生的先决条件。
对参与癌症预防项目（n = 1988）的维特努姆地区的 former 工人和居民进行研究，这些人已知石棉接触量（持续时间、强度和首次接触后的时间）、当前胸部X光片和吸烟信息。根据 UICC（ILO）分类，检查在进入癌症预防项目时拍摄的第一张胸部平片，以寻找石棉沉着病的影像学证据。使用Cox比例风险模型来关联石棉沉着病、石棉接触和肺癌。
1990年至2002年期间有58例肺癌病例。36%的病例有石棉沉着病的影像学证据，而研究参与者中这一比例为12%。吸烟状况是肺癌最强的预测因素，当前吸烟者（OR = 26.5，95%CI 3.5至198）风险最高。影像学上的石棉沉着病（OR = 1.94，95%CI 1.09至3.46）和石棉接触（每f/ml - 年OR = 1.21，95%CI 1.02至1.42）与肺癌风险增加显著相关。在没有石棉沉着病的人群中，肺癌风险随着接触量增加而增加。
在这个维特努姆地区的 former工人和居民队列中，石棉沉着病不是石棉相关肺癌的必要先兆。这些发现支持了这样的假设，即导致肺癌的是石棉纤维本身，无论是否存在石棉沉着病，肺癌都可能发生。
