Tumors are named by their parenchymal cells 2. Epithelial benign neoplasms may also be classified on microscopic architecture or microscopic patterns. These are growths beyond normal structure. If the growth is capable of metastisizing it is considered malignant or cancerous. If it stays encased or enclosed in one lump, it is benign.
Benign tumors can go through further genetic change and turn into malignant tumors.
There are a number of genes that control cell division. The proteins that are made from these genes are involved in a number of processes that occur only during cell division. They are normally under feedback control so that the proteins are only made when the cell is ready to go into cell division. Some of the genes are known to be receptors on the cell surface for contact with neighboring cells. Some stimulate DNA replication.