Respiration and Respiratory Systems

Up to the time of World War II, cancer of the lung was a relatively rare condition.Since then, many further studies in diverse countries have confirmed this conclusion.The incidence of lung cancer mortality in women, however, is increasing.The reason for the carcinogenicity of tobacco smoke is not known.In some cases a small tumour metastasis in the skin may be the first sign of the disease.Survival from lung cancer has improved very little in the past 40 years.Therefore, attention has been turned to prevention by every means possible.Persons exposed to radon daughters are at risk for lung cancer.Some types of lung cancer are unrelated to cigarette smoking.But in multifactorial disease, this is not possible.