Smoking is the greatest preventable cause of cancer Worldwide, nearly 1200 million people smoke and other hundreds of millions are smokeless tobacco users. Cigarette smoking is estimated to cause many more than 1 million cancer deaths annually worldwide and it includes 27% of all cancer deaths in developed countries and 34%in USA.

Cigarettes are the main type of tobacco product consumed.

Other smoked products include

• Kreteks : which are clove-flavored cigarettes popular in Indonesia
• Bidis : which consist of a small amount of tobacco wrapped in temburni leaf and tied with a string, are popular in India and neighboring areas.
• Cigars and pipes
• Smokeless Tobacco Products, including chewing tobacco, moist snuff that is placed between the cheek and gum, and pan or betel quid, a product that often contains tobacco and is used extensively in India

Tobacco and Lung Cancer:

At least 14 types of cancer are caused to some extent by cigarette smoking, with lung cancer being quantitatively the most deadly among these. The strongest determinant of lung cancer in smokers is the duration of smoking, and number of cigarettes smoked. Smoking causes lung cancer in both men and women. Cessation of smoking at any age can avoid the further increase in risk of lung cancer caused by continued smoking. However, the risk of exsmokers for lung cancer remains elevated for years after cessation, compared with the risk of never smokers.

Other cancers caused by tobacco (smoking/ Smokeless)

• Transitional cell carcinomas of the bladder
• Ureter, and renal pelvis
• Cancer of the oral cavity, including the lip and tongue in both men and women. Alcohol consumption in combination with smoking greatly increases the risk of oral cancer.
• Sinonasal and Nasopharyngeal cancer
• Oropharyngeal and Hypopharyngeal cancer
• Cancer of the esophagusand
• Laryngeal cancer is caused by cigarette smoking, and the risk is greatly enhanced by alcohol consumption.
• Pancreatic cancer and Stomach cancer are caused by cigarette smoking.
• Liver cancer, independent of the effects of hepatitis B and C virus infection and alcohol consumption.
• Cervical squamous cell carcinoma
• Myeloid leukemia in adults is also causally related to cigarette smoking.

Can nonsmokers be affected by cancer:

 

Nonsmokers are exposed as secondary (Secondhand smoke) like spouse and parents smoking at home, smokig at workplace and pulic places. In spouses of smokers, the excess risk is about 20% in women and 30% in men. Workplace exposures to secondhand smoke also increase lung cancer risk in nonsmokers, by 12% to 19%.

How does tobacco cause cancer?

Cancer is the consequence of the addictive power of nicotine, a noncarcinogen, coupled with the simultaneous delivery of multiple carcinogenic compounds. The carcinogenicity of cigarette smoke as well as smokeless tobacco has been clearly demonstrated in laboratory studies and humans. Nearly 68 components of cigarette has proven role to cause cancer and they are known as carcinogens. These carcinogens they cause some interaction with DNA and thus making some alteration in the DNA code. These lead to some mutation and will lead to the deadly disease.

 

Different organizations like WHO and national governments are now taking necessary steps to curb the smoking. Different legislations have been made to make people aware of the deadly disease like statutory warning on packets, Picture of lung cancer on the packet, No smoking zones, smoking in public places are punishable offence etc. With all these if the person himself is not aware and takes a decision to stop smoking no legislation can help.

Related articles

• Study: Smoking hookah presents higher cancer risk than cigarettes (fox4kc.com)
• Facts about Tobacco consumption in India (drsumandas.wordpress.com)
• How Secondhand Smoke Affects Non-Smokers (everydayhealth.com)
• Smokers Die Ten Years Sooner Than Non-Smokers – Part 2 (medicalnewstoday.com)
• Laryngeal Cancer: Some Important Risk Factors (heartburn.answers.com)