Cancer cells may start to form because the old cells that are supposed to undergo the normal process of dying refuse to die. Instead, they mutate and they start to form new cells that will go undetected by the immune system. Once the cells become too many, they may become tumors. The tumors will start getting bigger.
The rapidness of the growth will depend on the area where the cancer cells have started to form. When the cells are detected, they will be hopefully removed from the body before they spread so that they have a lesser chance of spreading once again. There are some factors that are considered to increase cancer cell growth.
There are different toxins that can be found in the air that can cause some cells to become abnormal. The moment that one cell starts acting abnormally, it is going to cause changes to the usual cellular DNA. When this one cell grows and multiplies too much, it can form a lump in any part of your body. Take note that there are some tumors that are benign.
This means that these tumors do not cause issues to the body although they may still need to be removed so they would not turn malignant or they will not press on other body parts. Cancer cells do not experience death. Rather, they continue to grow and divide unless they are stopped with the right treatment.