The cytomorphology of ocular surface squamous neoplasia by using impression cytology

The term ocular surface squamous neoplasia (OSSN) encompasses conjunctival and corneal intraepithelial neoplasia through to invasive squamous cell carcinoma of the ocular surface. The disease is related to prolonged exposure to solar ultraviolet light and has been proposed as an acquired immune deficiency syndrome-associated tumor. To the authors' knowledge, very few reports describing the cytology of these lesions have been published.

Impression cytology (IC) samples collected from the eyes of patients with a range of ocular surface diseases were available for study. From these, 267 sets of impressions had subsequent histopathology that had been collected within 6 months of the IC, and which indicated the presence of OSSN. The IC from these cases was used to describe the cytomorphology of intraepithelial and invasive OSSN.

Within the intraepithelial group, keratinized dysplastic cells that often were accompanied by hyperkeratosis, syncytial-like groupings, and nonkeratinized dysplastic cells were described. Within the invasive group, cases with significant keratinization and an additional group of cases with little keratinization and sometimes also prominent macronucleoli were described. Keratinized cases were the most numerous in both the intraepithelial and invasive groups. A description also was given of a low number of cases with cytology and also subsequent histopathology indicating the presence of intraepithelial OSSN, in the absence of a clinically detectable lesion.

This detailed description of the cytomorphology of a high number of cases of OSSN with confirmation by histopathology should assist others with little experience of the cytology of these lesions to examine them with increased confidence. Cancer (Cancer Cytopathol)