Colorectal Cancer - What Happens
How cancer grows and spreads
Cancer is the growth of
abnormal cells in the body. These extra cells grow together and form masses,
called tumors. In
colorectal cancer, these growths usually start as
polyps in the
large intestine (colon or rectum).
If colon polyps aren't found and removed, they may turn into
Cancers in the colon or rectum usually grow very slowly.
It takes most of them years to become large enough to cause symptoms. If the
cancer is allowed to grow, over time it will invade and destroy nearby tissues
and then spread farther. Colorectal cancer spreads first to nearby
lymph nodes. From there it may spread to other parts
of the body, usually the liver. It may also spread to the lungs, and less
often, to other organs in the body.
The long-term outcome, or
prognosis, for colorectal cancer depends on how much the cancer has grown and
spread. Experts talk about prognosis in terms of "5-year survival rates." This means the percentage of people who are still alive 5 years
or longer after their cancer was found. It is important to remember that
these are only averages. Everyone's case is different. And these numbers don't
necessarily show what will happen to you. The estimated 5-year survival rate
for colorectal cancer is:1
- 90% or more if cancer is found early and
treated before it has spread. This means that 90 or more out of 100 people will still be alive in 5 years if the cancer is found early and treated before it has spread.
- 69% if the cancer has spread to
nearby organs and lymph nodes. This means that 69 out of 100 people will still be alive in 5 years if the cancer has spread to
nearby organs and lymph nodes.
- 12% if the cancer has spread to the
liver, lungs, or bones. This means that 12 out of 100 people will still be alive in 5 years if the cancer has spread to the
liver, lungs, or other organs in the body.
These numbers are taken from reports that were done at least 5 years ago, before newer treatments were available. So the actual chances of your survival are likely to be higher than these numbers.