Why are Metastasis & tumors fatal?

hivesaeed4

I read the following online:

Metastasis is the process where cancer breaks out from where a tumour has initially grown and spreads to other parts of the body. It is usually the reason why cancer is fatal.


Now if the cancer would'nt spread then would'nt it still be fatal as the place where the cancer started, would eventually become a tumor. Also is the reason that the spread of cancer fatal because tumors will form at multiple locations throughout the body?

And why exactly is a tumour bad for health?

jedishrfu

Malignant tumors increasingly block normal body processes so for example in the brain, a malignant tumor would divert blood flow to itself depriving nearby neurons of blood which starves them to death. As it grows it distorts the architecture of the brain that again may cut off blood flow to other parts of the brain...

http://en.wikipedia.org/wiki/Metastasis

Curious3141

I believe this question has been addressed quite thoroughly in an earlier thread: http://www.physicsforums.com/showthread.php?t=426524

hivesaeed4

Thanks Guys. The links were really helpful.