Koilocytosis in oral squamous cell carcinoma: what does it mean?

(1) To determine the prognosis of patients with squamous cell carcinoma (SCC) of the oral cavity and (2) to determine whether a relationship exists between koilocytosis and tumour grade, stage, and prognosis in these patients.

Retrospective study of patients with SCC of the oral cavity at McGill University in the last 5 years followed by a pathology review of available cases. The data extracted were age at diagnosis, risk factors, tumour stage and grade, koilocytosis, treatment, and outcome. Deoxyribonucleic acid (DNA) extraction was done, followed by polymerase chain reaction (PCR) to detect the presence of human papillomavirus (HPV).

One hundred ninety-nine patients were identified. There was an overall 13% mortality rate over the follow-up period of 5 years. Pathology material was available for 146 patients. Koilocytosis was found in 67% of patients. More specifically, koilocytosis was present in 67.2% of well-differentiated lesions, 65.2% of moderately differentiated lesions, and 68.4% of poorly differentiated lesions. Koilocytosis was evenly distributed among tumour stages (I, 73%; II, 68%; III, 68%; IV, 69%). PCR was positive in only one sample.

Mortality rates in this series are similar to those published in the literature. There is a high prevalence of koilocytosis in SCC of the oral cavity, which appears to be associated with better tumour differentiation and poorly differentiated equally and also evenly distributed among tumour. Because HPV is negative, we do not know if koilocytosis is a marker of HPV. We could not determine the relationship between HPV and prognosis.