Conjunctival intraepithelial neoplasia

Abstract

I would like to congratulate Yamamoto et al1Yamamoto N. Ohmura T. Suzuki H. Shirasawa H. Successful treatment with 5-fluorouracil of conjunctival intraepithelial neoplasia refractive to mitomycin-C.Ophthalmology. 2002; 109: 249-252Abstract Full Text Full Text PDF PubMed Scopus (51) Google Scholar for embracing the topical chemotherapeutic treatment of conjunctival intraepithelial neoplasia (CIN). In their article, they report a patient who was first treated for CIN by conventional surgical approaches, then, after recurrence, treated with mitomycin-C (MMC) topically, unfortunately without success. Upon switching topical treatment to 5 fluorouracil (5 FU), the patient’s lesion regressed completely. Their discussion of MMC and 5 FU is complete, acknowledging the limitation and long-term documented risks of the two agents. They did not discuss, however, Karp’s landmark investigations on the use of topical interferon alpha 2b (IFN) for CIN.2Karp C.L. Moore J.K. Rosa Jr, R.H. Treatment of conjunctival and corneal intraepithelial neoplasia with topical interferon alpha-2b.Ophthalmology. 2001; 108: 1093-1098Abstract Full Text Full Text PDF PubMed Scopus (120) Google Scholar, 3Vann R.R. Karp C.L. Perilesional and topical interferon alpha-2b for conjunctival and corneal neoplasia.Ophthalmology. 1999; 106: 91-97Abstract Full Text Full Text PDF PubMed Scopus (119) Google Scholar I have treated several patients with CIN using topical IFN and have achieved complete regression in all but two cases (unpublished data). Interferon’s mechanism of action is quite different than either MMC or 5 FU and its performance is impressive. Of particular importance is the lack of local and ocular surface effects in the treatment period and the lack of reported long-term complications from its use. Admittedly, the track history is short, but interferons lack of known effect on healthy fibroblasts and vascular endothelial cells comforts the risk-averse surgeon’s concerns about long-term safety. Topical chemotherapeutic treatment of CIN has several advantages over surgical excision, including preservation of maximal number of limbal stem cells. As underscored by Yamamoto and colleagues’ article, a number of agents have now been shown to be effective in treating CIN topically. This should encourage ophthalmologists who treat patients with CIN to consider adding topical interferon alpha 2b therapy to their armamentarium.