Some molecular lesions causing breast cancer in mice have not been found in human breast cancer. Similar morphological patterns of lesions appear in both species The morphology of most mouse tumors does not resemble the common human breast cancers. Development of cancer consistent with multi-hit kinetics.
Some transgenes appear to be associated with one- hit kinetics.
Breast cancers in both species are metastatic. Most tumors mouse metastasize to the lung. Most human metastasize to the regional lymph nodes. Both species have distinctive host responses to the cancers. The mouse generally does not respond to its tumor with as much fibrosis and inflammation.