Causes of lung cancer in non-smokers

Introduction

Lung cancer is caused by uncontrolled reproduction of malignant cells in the lungs. This sever disease takes the second place in frequency, just behind breast cancer with the women and prostate cancer with men and it is the most common cause of death among malignant diseases.

It is believed that the world has more than 2.1 million of new diseased people per year.

Risk Factors

The most important risk factor for developing lung cancer is smoking. Smoking provokes 90% of lung cancer. Cigarette smoke contains more than 60 chemical substances that are proven trigger of malignant process in the body. The risk of death due to lung cancer increases directly with duration of smoking "experience" and the number of cigarettes per day. Passive smoking – sharing closed space with smokers and smoke inhalation is considered to be the cause of 25% of non-smokers lung cancer cases. Smokers partners have 20% bigger chances to develop lung cancer. Besides passive smoking, several other well known environmental factors influence on developing lung cancer in non-smokers. These factors include alcoholism, increased level of cholesterol and too much fat in the body and exposure to asbestos, uranium radioactive dust and gas radon. Also, age, race, sex and genetic inheritance have an important role in the development of this disease.

The Latest Discoveries

Gene mutations could be the cause of increased risk of lung cancer among people who have never used the tobacco, showed the results of international research published in the electronic edition of the medical journal Lancet Oncology.

The international group of scientists conducted a study in four phases in order to try to identify the gene mutation which presence increases the risk of lung cancer among non-smokers.

The expert team identified the gene mutation at the 13th chromosome which increases the risk of developing lung cancer in nonsmokers for 60%. These gene mutations, according to scientists, could affect the role of GPC5 genes and thus encourage the development of lung cancer in nonsmokers. Researchers, however, emphasize that it is necessary to conduct additional researches to determine the functional role of GPC5 genes.

Smoking is still the leading cause of lung cancer, so, smokers are exposed to 15 - 20 times greater risk of developing lung cancer compared with non-smokers.

Fifteen (15) percent of men and 53 percent of women who have the lung cancer have never been smokers or have smoked less than 100 cigarettes during entire life.