Metastasis of a cancer. In metastasis, cells break away from a primary tumor, enter the circulatory system, and establish one or more secondary tumors elsewhere in the body. A neoplasm is an uncontrolled growing mass of abnormal cells, also called a tumor. Oncogenesis is the formation of a cancer cell or tumor The creation of a malignant tumor in epithelial tissue is depicted schematically above. Epithelial cancers are the most common malignancies and are called carcinomas.
Breast cancer is the most common malignant cancer of women in the western world.
While prostate cancer is the most common cancer in men in the United States. As the cell cycle proceeds, generation after generation, mitosis alternates with a long interphase. Failures in regulation of the cell cycle can lead to cancer. The cell cycle repeats over and over as long as the nuclei are going to divide. A nucleus that is not going to divide may enter the G0 phase.