The use of antimetabolites as adjunctive therapy in the surgical treatment of pterygium

BACKGROUND Pterygium is a proliferative disease with hyperplastic growth of corneoconjunctival fibro vascular tissue onto the cornea. Surgical therapy can be used to successfully manage pterygia; however, recurrence remains a problem. To reduce recurrence, surgical management may include autoconjunctival grafting, lamellar keratoplasty, amniotic membrane transplantation, and intraoperative antimetabolites application. PURPOSE To assess the safety and the efficacy of intraoperative mitomycin C (MMC) and 5-fluorouracil (5-FU) application in preventing recurrence of pterygium after excision. PATIENTS AND METHODS The study design is a prospective, randomized clinical trial. A total of 50 patients with bilateral pterygium were recruited for the study. The first group of patients (25) underwent surgical excision of the pterygium with bare sclera in one eye and MMC was applied as adjunctive therapy for the other eye. In the second group 5-FU was used instead of MMC. Recurrences and postoperative complications were measured in the two groups. The mean follow up period of the patients was 18.8 months. Chi square test, odds ratio, and frequency distribution were used to determine significance levels; P-values <0.05 were considered statistically significant. RESULTS In group 1 the recurrence rate was 8% for the MMC treated eyes and 32% for their fellow eyes (P = 0.03). In group 2 the rate was 18% for the 5-FU treated eyes and 34% for their fellow eyes (P = 0.07). No serious complications were recorded in either group. CONCLUSION Both MMC and 5-FU reduce the recurrence rate of pterygium after simple surgical excision; statistically, the effect of the former was significant, but insignificant for the latter. Both antimetabolites were safe during the whole study period, but 5-FU recurrent cases showed cosmetically unacceptable appearances with excessive vascularization. MMC, but not 5-FU, is recommended as an adjunctive therapy to prevent recurrence of pterygium after surgical excision.