Atmospheric depletion of the ozone layer continues to put us at risk of ultraviolet related malignant neoplasia.^1–3 This problem is even worse beneath the Antarctic ozone hole that affects Australia.⁴ In this issue of BJO (p 819), two Australians, Khong and Muecke, report on a retrospective study of the ocular side effects of topical mitomycin chemotherapy (TMC) on 100 eyes treated for malignant ocular surface neoplasias.⁵ This single centre study employed up to three alternate 7 day TMC cycles and one concentration of mitomycin (0.04%) given four times a day. Eighty five eyes were treated for localised, diffuse, or recurrent malignant squamous conjunctival neoplasia, 12 for melanocytic conjunctival neoplasia, two with sebaceous carcinoma, and one with recurrent atypical fibroxanthoma. The most commonly reported side effects of TMC were allergic reaction (n = 31, 34%) and epiphora secondary to punctual stenosis (n = 14, 14%) at a mean follow up of 26.5 months (range 3–69 months). The authors present these complications as an acceptable risk and support the continued use of TMC for selected cases of malignant conjunctival and corneal neoplasia.

However, Khong and Muecke’s report has its limitations. Their conclusions must be qualified by their methods of clinical practice. For example, their TMC study employed case selection, stopped after moderate term follow up, and paid little attention to systemic side effects. The authors’ conclusions concerning safety must be limited by three specific factors: most patients were treated with only one concentration of mitomycin (0.04%) topically administered four times a day using a “week on and week off regimen,” the “treatment was only commenced after complete epithelial healing was achieved,” and that “punctal plugs were not used during MMC treatment in any of our cases.” Let us explore …