how do you die from cancer?

I know cancer might be deadly but why do you die? Is it because a body can't survive beside less than a ceirtain number of cell (after a bunch has be attacked) or is it because of a kind of some gentle of poisoning? my dad died of lung cancer. The cancerous cells replaced the worthy ones and didnt do the job of the feeble ones. Cancer kills because the organs artificial stop working as their working cells are replaced.
Cancer cell gobble down everything, including fellow cells. So, as the disease progresses, the body is both starved of nutrients, and the incapacitate becomes too much to repair.
One of the frightening things around cancer is the possibility of metastasis. This is the process where millions of malignant cell are released from the tumor (the primary) into the bloodstream. Fortunately, most of these cells are kill by trauma produced while traveling within the blood vessel walls, or by circulating cell from the immune system, like the Natural Killer (NK) cell and other T lymphocytes. Other immune cells that fight malignant cells are macrophages, antigen-presenting cell, and substances produced by immune cells call lymphokines. One common lymphokine is call interleukin-2 (IL-2) or interferon. (See How the Immune System Works for details on these different components of the immune system.) In some cases, the circulating malignant cells survive and fit tightly to the inner muscular lining of the blood vessel walls. Here the process of tumor formation can instigate in a different nouns of the body (the secondary), causing further destruction.