Koilocyte

Overview
Koilocytes are a type of dysplastic squamous cell found in precancerous cervical lesions.

Laboratory findings
They have the following characteristics:


 * Nuclear enlargement (two to three times normal size)
 * Irregularity in the nuclear contour (occasionally)
 * Hyperchromasia; (occasionally)
 * Perinuclear clearing

Koilocytosis (a.k.a koilocytotic atypia) are cellular changes in which cells appear to have halo nuclei on cytologic examination. Histologic review usually reveals an abnormal lesion composed of intermediate and superficial squamous cells of the vaginal epithelium. Koilocytosis is characteristic of a diagnosis of ASC-US (atypical squamous cells - undetermined significance) by cytologists if the degree of koilocytosis appears minute. A more differentiated koilocyte, possessing a more hyperchromatic and enlarged nucleus, and a higher degree of cytoplasmic clearing with a discernible peripheral rim favor an interpretation of LSIL (low-grade squamous intraepithelial lesion [formerly known as CIN-1]). These changes occur in the presence of human papilloma virus, and occasionally can lead to cervical dysplasia, and eventually malignant cancer. Cases of cancer development are commonly associated with HPV types 16 or 18.

Coilocito