Abstract
Glands cancers consider the most types of cancers in males or females or both. Many challenges are present in controlling cancers in dogs, the first one is related to populations of tumour cells define as cancer stem cells, cancer cells are resistant to chemotherapy and have the ability to metastasise and returned after successful treatment. Cancer consists of different cells that contain a subtype of cell with stemness characteristics, like high tumourigenicity, the self-renew ability to differentiate and resistance to chemo and radiotherapy. These cells are termed cancer stem cells (CSCs) and are involved in the initiation of tumours, recurrence and metastasis. Canine mammary cell tumours are malignant neoplasms characterized by metastasis and a high infiltration rate. Canine mammary tumours (CMT) occur in female dogs frequently, six to seven (6-7) years old animals ages are more susceptible to the disease, however, it can be diagnosed at 9–11 years of age, which is known as the cancer age, it has the ability to form tumours spheres which are considered a characteristic of stem cells. it is difficult to clarify the histological finding base on Hematoxyline and Eosin stains policy, so biomarkers are recommended like CD44+and CD24- ,also Immunohistochemistry . These tumours are composed of mesenchymal cells andor myoepithelial cells with proliferative luminal epithelial cells, cartilage, and osseous tissues. Annually around the world, between 200-250 mammary gland tumours out of 100.000 female dogs, 50% were malignant. Surgical removal is the treatment of choice, however, it is ineffective because of the metastasis high rate. It is important to focus on the analysis of CSCs high incidences in dogs (bitches) and CSCs isolation and diagnosis.