Basing on references from literature it has been looked for possibilities to characterize benign lesions of the breast by endocrine data and to find a discrimination between types connected with high or low risk for breast cancer. Conventional investigations of hormonal excretions and measurements of plasma contents only provide data for statistical evaluations which can not be used to assess the situation of an individual patient. Obviously one has to look for the processes of hormonal promotion on a cellular level. These processes are thought to realize a non-hormonal initial event to a benign or malignant disease. This requires finding of corresponding representative data. Some possibilities as receptor investigations or recording of hormone induced secretion proteins have been discussed.