[Differential diagnosis and prognosis of 112 excised epibulbar epithelial tumors]

Epithelial tumors of the epibulbar conjunctiva are rare in northern Europe. There are no reliable clinical criteria to predict the histological nature of the lesion. Even histologically proven malignant tumors typically do not show ocular invasion or metastasis.

From 1980 to 1993, 112 epithelial epibulbar tumors were classified in our ophthalmopathological laboratory. Surgical management of 50 papillomas (mean age 46 +/- 18 years, 58% males), 49 conjunctival/corneal intraepithelial neoplasias (CIN) (28 mild, 21 severe) and 12 squamous cell carcinomas (mean age 63 +/- 13 years, 69% males) included excisional biopsy (61%), with additional lamellar keratectomy (14%), epithelial abrasion (10%), cauterisation (3%), cryotherapy (2%), excimer laser ablation (2%). Other management regimes were lamellar keratoplasty (2%), penetrating keratoplasty (2%), epithelial abrasion (2%). One eye with intraocular invasion of a mucoepidermoid carcinoma was enucleated.

Fifty five per cent of the papillomas were located at the caruncle or semilunar fold. Seventy eight percent of the papillomas had a pedunculated appearance. Two lesions involved the epibulbar conjunctiva as well as the opposite tarsal conjunctiva ("kissing papilloma"). Eighty eight percent of CIN/carcinoma were located at the limbus. The clinical differential diagnoses of CIN/carcinoma were squamous cell carcinoma (26%), papilloma (18%), leukoplakia (10%), pinguecula/pterygium (10%), dysplasia (8%), malignant melanoma (5%), trachoma (3%), chronic keratoconjunctivitis with corneal pannus (2%), "granuloma" (2%), non-pigmented naevus (2%). After a mean follow-up of 6.3 +/- 3.5 years, 13% of the papillomas showed a local recurrence. After a mean follow-up of 4.8 +/- 3.7 years, there were 30% local recurrences of CIN/carcinoma (50% each in severe CIN and carcinoma, 9% in mild CIN). But there was no recurrence of CIN/carcinoma in patients who had received a complete tumor resection initially. If the surgical margins were involved, there was a 64% recurrence rate (80% each in severe CIN and carcinoma). Thirteen per cent of the patients with CIN/carcinoma showed an additional malignant tumor elsewhere in the body.

Local recurrences after excision of CIN/carcinoma did occur only if the surgical margins where involved, and most often within the first year following surgery. Dedifferentiation of epithelial tumors in recurrences was not observed. The diagnosis of CIN/carcinoma of the conjunctiva requires the exclusion of an additional extraocular neoplasia. Histopathological classification and assessment of resection margins of epibulbar tumors is indispensable, especially in view of the more aggressive treatment necessary in mucoepidermoid carcinomas.