Treatment of ocular surface squamous cell intraepithelial neoplasia with and without mitomycin C.

Purpose: To analyze the outcome of excisional biopsy of ocular surface (conjunctival and corneal) squamous cell intraepithelial (in situ) neoplasia with and without the adjunctive use of intraoperative and postoperative mitomycin C.

Methods: A retrospective case review was conducted on 34 consecutive patients with histopathologically proven ocular surface squamous cell intraepithelial neoplasia who were treated from January 1, 1980, to December 31, 2008, at University of Iowa Hospitals and Clinics. Eyes in which a minimum follow-up period of 3 months was available were included in the statistical analysis.

Results: Of 34 eyes, 32 met the inclusion criteria. Adjunctive therapy was provided with mitomycin C in 17 eyes, including 13 that had only postoperative treatment and 4 that had only intraoperative treatment. The adjunctive use of mitomycin C was associated with a significantly reduced prevalence of recurrence (5.9% vs. 66.7%; P = 0.0005). When the surgical margins were positive, the use of adjunctive mitomycin C was associated with a reduced prevalence of tumor recurrence (12.5% vs. 55.6%), but this difference was not statistically significant (P = 0.13). When surgical margins were negative, the adjunctive use of mitomycin C was significantly associated with a reduced prevalence of recurrence (0% vs. 83.3%; P = 0.002).

Conclusions: The adjunctive use of mitomycin C is significantly associated with a reduction in the prevalence of postoperative recurrences of ocular surface squamous cell intraepithelial neoplasia and should be considered as an adjunctive therapy even when surgical margins are negative.