Additionally, in acute lymphoblastic leukemia (ALL)/acute undifferentiated leukemia (AUL) and chronic lymphocytic leukemia (CLL), increased expression of c-KIT was observed123, suggesting the use of tyrosine kinase inhibitors as a treatment option for canine leukemia patients, and this treatment is commonly used in human leukemia patients with tyrosine kinase-related aberrations. This evidence concerns the gene KIT and B-cell chronic lymphocytic leukemia.