CLINICAL PREDICTIVE FACTORS FOR DEVELOPMENT OF RECURRENCE AND METASTASIS IN CONJUNCTIVAL MELANOMA - A REVIEW OF 68 CASES

Sixty eight cases of histologically proved conjunctival melanoma were reviewed in order to determine the clinical factors that were predictive of local recurrence and distant metastasis. All patients were treated with surgical excision and most had supplemental cryotherapy. The mean follow up was 7.5 years. Histopathologically, the conjunctival melanoma arose from primary acquired melanosis in 56%, from naevus in 26%, and de novo in 18%. Of the 68 patients, 38 (56%) developed at least one local tumour recurrence and 22 (32%) developed more than one recurrence. The method of initial treatment and the eventual development of metastasis were the two parameters statistically associated with tumour recurrence. Those patients treated initially with tumour excision alone had a statistically significant higher recurrence rate than those treated initially with excision and supplemental cryotherapy (p=0.001). Fourteen patients (21%) developed metastasis and the mean period between treatment and metastasis was 3.6 years. Twelve (18%) died from metastatic melanoma with a mean interval of 4-4 years from the time of initial surgery until death. The only clinical parameter that was statistically associated with distant metastasis was local tumour recurrence (p=0.015). Based on these observations, the authors make recommendations regarding the treatment of conjunctival malignant melanoma. It appears that initial complete excision of the tumour with supplemental cryotherapy offers the patient the best chance of remaining free of recurrence and metastasis.