Development Of Cancer: If the control of mitosis by the genes in a cell goes wrong, those cells start to replicate. They then start to form into cancer cells. These cancer cells form into tumors that damage the surrounding tissue. They also replicate themselves and make more tumors known as secondary tumors. So, in essence, cancer occurs because of a genetic mutation of cancer cells not developing the way they should be. Whether it be too many cancer cells, or an unusual number of chromosomes. Cancer can develop almost anywhere on the body.
Malignant: characterized by uncontrolled growth; cancerous, invasive, or metastatic
Tumor: a swelling of the part of the body caused by an abnormal growth of tissue
Mitosis ~ Maintaining Homeostasis: Since cells often become damaged and die, mitosis is known to be helpful for maintaining homeostasis due to its control of the metabolism for the process to take place. Basically, when equilibrium with the body occurs, homeostasis takes place. These are new adjustments that are made to the body.
http://www.biology.iupui.edu/biocourses/N100/2k4ch8mitosisnotes.html