Conjunctival melanoma: risk factors for recurrence, exenteration, metastasis, and death in 150 consecutive patients

Abstract

Objective: To identify the risk factors of conjunctival malignant melanoma that predict local tumor recurrence, orbital exenteration, distant metastasis, and tumor-related mortality.

Design: The study group consisted of 150 consecutive patients with a diagnosis of conjunctival melanoma. The clinical parameters of the patient, tumor, and treatment were analyzed in a nonrandomized fashion for their relation to 4 main outcome measures using Cox proportional hazards regression models.

Results: The Kaplan-Meier estimate of local tumor recurrence was 26% at 5 years, 51% at 10 years, and 65% at 15 years. The mean number of recurrences per patient was 1 (median, 0). Ninety-eight patients (65%) had no recurrences, 28 patients (19%) had 1, 11 patients (7%) had 2, 5 patients (3%) had 3, and 8 patients (5%) had 4 or more recurrences. According to multivariate analysis, the factors that predicted local tumor recurrence were the location of the melanoma (not touching the limbus) (P = .01) and tumor-margin pathology (lateral margin involved) (P = .02). Multivariate analysis for features predictive of ultimate exenteration included initial visual acuity (20/40 or worse) (P = .0007), melanoma color (red) (P = .01), and melanoma location (not touching the limbus) (P = .02). Tumor metastasis occurred in 16% of patients at 5 years, 26% at 10 years, and 32% at 15 years. Metastasis was initially in the regional lymph nodes in 17 cases, brain in 4, liver in 3, lung in 2, and disseminated in 1 case. Risks for metastases with use of multivariate analysis included tumor-margin pathology (lateral margin involved) (P = .002) and melanoma location (not touching limbus) (P = .04). Tumor-related death occurred in 7% of patients at 5 years and 13% at 8 years. Risk factors for death with use of multivariate analysis included initial symptoms (lump) (P = .004) and pathologic findings (de novo melanoma without primary acquired melanosis) (P = .05). In a series of univariate analyses, the technique of initial surgery was shown to be an important factor in preventing eventual tumor recurrence (P = .07), metastasis (P = .03), and death (P = .006). Patients who were managed with excisional biopsy using the "no-touch technique" plus alcohol corneal epitheliectomy and supplemental cryotherapy fared far better than those treated with excisional biopsy alone. In addition, the surgical technique used before referral to us was critical. Those patients who had an incisional diagnostic biopsy prior to referral were at risk for more than 1 recurrence (P = .04), and those who had excisional biopsy alone without supplemental cryotherapy were at risk for eventual exenteration (P = .0006) and death (P = .04).

Conclusions: Conjunctival malignant melanoma is a potentially deadly tumor. In this study, metastasis was detected in 26% of patients and death occurs in 13% at 10 years. The surgical technique of tumor management was found to be possibly related to tumor metastases and death. Meticulous surgical planning, use of wide microsurgical excisional biopsy with the no-touch technique, and supplemental alcohol corneal epitheliectomy and conjunctival cryotherapy performed by experienced surgeons are advised. Incisional biopsy should be avoided.