Metastasis from uveal melanoma associated with congenital ocular melanocytosis: a matched study

Purpose: To determine the rate of metastasis resulting from uveal melanoma associated with congenital ocular melanocytosis (COM) and to compare it with the rate of metastasis resulting from uveal melanoma not associated with COM.

Design: Matched retrospective study.

Participants: Fifty-seven patients with uveal melanoma associated with ocular melanocytosis (melanocytosis group). Each patient in the melanocytosis group was matched with 2 patients with uveal melanoma not associated with ocular melanocytosis (no melanocytosis group) for age, gender, location of anterior tumor margin, location of tumor epicenter, tumor basal diameter, and tumor thickness.

Methods: Review of medical records.

Main outcome measures: Metastasis resulting from uveal melanoma.

Results: The mean basal diameter and thickness of tumors in the melanocytosis group were 10 and 4.9 mm, respectively, and most were located between the macula and equator (70%). The melanocytosis and no melanocytosis groups were similar with regard to all patient, ocular, and tumor features studied. Nineteen (33%) of 57 patients in the melanocytosis group and 18 (16%) of 114 patients in the no melanocytosis group demonstrated systemic metastasis during mean follow-up periods of 77 months (range, 1-402) and 64 months (range, 1-252), respectively (P = 0.013). The Kaplan-Meier estimates for systemic metastasis in the melanocytosis group at 5 and 15 years were 27% and 59%, respectively, compared with 15% and 33%, respectively, in the no melanocytosis group (hazard ratio, 1.99; 95% confidence interval, 1.16-3.41).

Conclusions: In this matched study, patients with uveal melanoma associated with COM were twice as likely to have systemic metastasis compared with patients with uveal melanoma not associated with COM.

Financial disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article.