Last but not least, the perspective of subsequent histopathological verifications over time shows the process of dedifferentiation of the tumor (initially G2 Ki67 of 5%, then 20% in the liver, then already dedifferentiated cancer in the breast with Ki67 of 30% and 50% for left and right breasts, respectively) and its role is crucial in therapeutic decisions. The gene discussed is MKI67; the disease is neoplasm.