Abnormal cilia in a breast carcinoma. An ultrastructural study.

Epithelial cells bearing multiple cilia of the motile type were observed in an infiltrating ductal carcinoma of the postmenopausal breast. These cilia displayed a number of abnormalities, the most striking of which was the widespread occurrence of supernumerary single microtubules. While the presence of occasional cells with a single primary cilium is a common finding in a great variety of tumors, including breast neoplasms, the occurrence of cells with multiple abnormal cilia in malignant mammary epithelium is most intriguing and, to our knowledge, has not been documented before.