[Discovery and electron microscopic observation on unusual intranuclear inclusion bodies of breast carcinoma].

Unusual intranuclear inclusion bodies in one case of breast carcinoma discovered and studied by electron microscope is reported. The ultrastructural feature of these inclusion bodies is very characteristic and has not been reported previously. They presented with unequal sizes, location at the margin of nuclei, and frequent separation from the nuclear chromatin by a single thin membrane. These inclusion bodies can be divided into two kinds: one with granular central portion surrounded by numerous radiating flagella-like filaments, the other assuming concentric laminated arrangements. There are transitional forms between them. The nature of these intranuclear inclusion bodies are discussed.