The cytomorphology of ocular surface squamous neoplasia by using impression cytology

BACKGROUND. The term ocular surface squamous neoplasia (OSSN) encompasses c onjunctival and corneal intraepithelial neoplasia through to invasive squam ous cell carcinoma of the ocular surface. The disease is related to prolong ed exposure to solar ultraviolet light and has been proposed as an acquired immune deficiency syndrome-associated tumor. To the authors' knowledge, ve ry few reports describing the cytology of these lesions have been published . METHODS. Impression cytology (IC) samples collected from the eyes of patien ts with a range of ocular surface diseases were available for study. From t hese, 267 sets of impressions had subsequent histopathology that had been c ollected within 6 months of the IC, and which indicated the presence of OSS N. The IC from these cases was used to describe the cytomorphology of intra epithelial and invasive OSSN. RESULTS. Within the intraepithelial group, keratinized dysplastic cells tha t often were accompanied by hyperkeratosis, syncytial-like groupings, and n onkeratinized dysplastic cells were described. Within the invasive group, c ases with significant keratinization and an additional group of cases with little keratinization and sometimes also prominent macronucleoli were descr ibed. 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. CONCLUSIONS. This detailed description of the cytomorphology of a high numb er of cases of OSSN with confirmation by histopathology should assist other s with little experience of the cytology of these lesions to examine them w ith increased confidence. Cancer (Cancer Cytopathol) 2001;93:60-67. (C) 200 1 American Cancer Society.