During cancerous cell turnover activity maintained by two types of mitosis, maturation and heteroduplication, cancer tissue consists of two types of cells, maturable and non-maturable. Most of the tissue is composed of maturable cells, which eventually disappear in the terminally matured cell phase. These cells do not participate in cell turnover activity or the organoid identity of cancer tissue. However, a small portion of the tissue is comprised of non-maturable cells, which replicate themselves endlessly, while producing maturable cells through each mitotic division in hetero-duplication mitosis. Thus, cell turnover activity and organoid identity are established in the cancer tissue. This organoid identity is solely responsible for carcinogenesis. Since most typical features of cancer are only detectable in maturable cells during maturation mitosis, cell destruction targeting these features should not be regarded as eradication. To eradicate cancer, the organoid identity of cancer, which is only established by heteroduplication mitosis, should clearly be recognized, and a new concept of cancer treatment based on destruction of the organoid identity should be devised in the future. This does not appear to be an insurmountable task.