Abstract
A case report of needle aspiration cytology on sacrococcygeal chordoma is described here. The patient, an 80-year-old man, appeared at the first Surgery of Kurume University Hospital because of a pelvic tumor and an aspiration cytology was performed.
Cytologically, tumor cells were arranged in cords and sheets in a mucinous background. The tumor-cell cytoplasmic features were distinctive and some of the tumor cells (so-called physaliferous cells) contained one too many clear vacuoles-about 2 to 20 micron in diameter. Multiple small vacuoles were arranged around a nucleus and signet ring cell-like large vacuoles were also seen.
The electron microscopic observation revealed physaliferous cells, nonvacuolated stellate cells and transitional forms. The tumor cells were locked together by interdigitating cellular processes and desmosomes were present. These cells had many organelles including rough ER, bundles of microfilaments and clusters of glycogen.
The plasma membrane exhibited a large number of pinocytotic vesicles and occasionally the cytoplasmic intrusions appeared as intranuclear pseudoinclusion. The cytoplasmic vacuoles were of three types: distended rough ER, cytoplasmic vacuole and intercellular space. The signet ring cell-like large vacuoles were cytoplasmic vacuoles delimited by a single membrane and some of them contained a variable amount of amorphous granular materials.
