[Ultrastructural study of human breast cancer--relation to the basement membrane with invasive breast cancer].

The Japan Mammary Cancer Society's General Rules for Pathological Record prescribe differential diagnosis of the noninvasive or invasive status of human breast cancer upon discovery of basement membrane. We discovered basement membranes not only in normal mammary glands and non invasive breast cancers, but in metastatic breast cancers to the lungs and regional axillary lymph nodes. We concluded that, for such diagnosis, it is necessary to observe the cellular arrangement and condition of the surrounding stromal tissues with light microscopy. Nuclear chromatin patterns should also be examined; they showed predominantly euchromatin in invasive breast cancer and heterochromatin in non-invasive breast cancer with electron microscopy.