Cancer is a leading cause of death, wordwide. Among men the leading cancers are the lung cancer, stomach cancer, colorectal cancers, and the head and neck cancers.

Among women breast, cervix and uterine cancers form the largest bulk of cancers. Cancer forms due to changes in cell division. There are number of changes at the cellular level that are well documented to lead to the evolution of cancer. The cells lose their contact inhibition, and lose the function of the tumour suppressor genes. There is also an overexpression of certain genes called the oncogenes. These changes lead to multistep evolution of cancers called as carcinogenesis.

 

One of the well know cause of cancer is tobacco. Tobacco smoking is in the form of cigarrates, cigars, etc. Smokeless or spitting tobacco is the chewing tobacco popularly know as PAN in our country. Tobacco smoke has 3500 chemicals. There are 55 recorded carcinogens in tobacco. They are classified as Polycyclic aromatic hydrocarbons PAH Nitrosamines TSN, Aromatic amines. These Carcinogen s form DNA adducts which leads to cancer. Tobacco can affect many organs. For example:

 

Lung cancer: sq cell, large cell, small cell

 

Oral cavity, Pharynx, Larynx: sq. cell

 

Esophagus, liver

 

Kidney, bladder

 

Uterine cervix cancer

 

Blood: leukemia

 

Smoking causes 90% of all lung cancer deaths, and tobacco itself is the cause of 90% oral cavity cancers in men, and 60% of all oral cavity cancers in women. Tobacco is the made made monster of the twentieth century. The single largest health care step towards prevention of cancer will be ban tobacco altogether in all its forms.