Advanced conjunctival melanoma.

Background: Conjunctival melanoma is a rare neoplasm with an aggressive behaviour characterized by a high tendency to develop recurrences and metastases. The authors describe the clinicopathological features of four Mexican patients with advanced conjunctival melanoma.

Methods: Review of the cases of four patients with advanced conjunctival melanoma seen at an ophthalmologic referral centre in Mexico City. The clinical characteristics, gross findings and histopathological features were noted.

Results: The mean age of the patients (two women and two men) was 72 years (range 49 to 95 years). The left eye was affected in three cases and the right eye in one. Orbital exenteration was performed in two patients, enucleation in one and complete excision of the mass in one. One patient died 2 years after debulking surgery, and another patient is alive and free of disease 13 years after enucleation; the two other patients were lost to follow-up. The mean largest mass dimension of the tumours was 4 cm (range 3-5.4 cm). Histopathologically, all cases were associated with primary acquired melanosis with atypia. Two cases were composed of epithelioid cells, one of spindle cells, and one of a mixture of epithelioid and spindle cells. In three cases the number of mitotic figures ranged from 3 to 36/10 high-power fields; no mitotic activity could be demonstrated in one case.

Interpretation: The mean age of our patients at the time of diagnosis was older and their tumours were larger than those reported in other series. All the cases were associated with primary acquired melanosis with atypia. At the time of writing, one patient, who had a 3.3-cm tumour, had survived 13 years without clinically detectable disease.