The dynamic of tumor growth has been estimated in breast cancer using cytologic and histologic criteria. There were definite differences between primary tumors with simultaneously observed metastases and tumors which had metastasized within the first two years following primary treatment. The primary tumors of the recurrent diseases were receptor positive more seldom, and they had a significant lower receptor concentration. Morphologically they were composed of larger cells with polymorphism and more mitoses. Between primary tumors and metastases there were no significant differences. We suspect the grade of malignancy is a typical attribute of a tumor not changing after having metastasized or recidivation. Changing tumor growth is caused by other reasons like general resistance.