Question

why does cancer kills??

Answer 1

cancer is a type of disease in which the cells multiply (malignant)rapidly and leads to the formation of tumours and this multiplication of cells in such a rapid manner ultimately proves fatal 

Answer 2

Cancer is one of the most dreaded disease of human beings and is a major cause of death all over the world.
In our body cell differentiation and cell growth is highly controlled and regulated . In cancer cells there is a breakdown of these mechanisms. Normal cell show "contact inhibition" which means contact with other cells inhibit their uncontrolled growth . Cancer cells lose this property and start growing in uncontrolled manner. As a result of the growth they are able to make tumor which . There are two types of tumour ; malignant and benign tumor.
The uncontrolled growth deprive other body cells of nutrition and slowly affects every function which can be fatal or it can cause death .
Hope you understood.