Purpose: To analyze the clinical features and rate of metastatic disease in eyes with large (≥10 mm thickness) uveal melanoma.
Design: Retrospective noncomparative case series.
Participants: There were 1,311 consecutive patients.
Methods: Retrospective medical chart review.
Main outcome measures: Clinical features and rate of metastatic melanoma.
Results: Of 1,311 patients with large melanoma, the mean age was 59 years (median 60, range 6-98 years) and 95% were white. Mean tumor basal dimension was 17 mm (median 17, range 7-25 mm), and mean tumor thickness was 12 mm (median 12, range 10-24 mm). Mean distance to the foveola was 6 mm (median 6, range 0-19 mm) and to optic nerve was 6 mm (median 5, range 0-19 mm). Of all eyes, using Kaplan-Meier analysis, metastasis occurred in 11, 30, 45, and 52% at 1, 3, 5, and 7 years, respectively. According to tumor thickness (10.0-11.0, 11.1-12.0, 12.1-13.0, 13.1-14.0, 14.1-15.0, 15.1-16.0, and >16.0 mm), metastasis at 1 year was found in 7, 12, 13, 15, 18, 22, and 20%; metastasis at 3 years was 24, 27, 37, 35, 51, 69, and 57%; metastasis at 5 years was 38%, 42%, 56%, 48%, 61%, not available, and 66%; and metastasis at 7 years was 47%, 47%, 61%, 57%, 61%, not available, and 66%. Clinical features associated with fewer metastatic events included Bruch membrane rupture (7-year metastasis at 48%, P = 0.018) and macular location (7-year metastasis at 32%, P = 0.014), whereas those with worse outcome included extraocular extension (7-year metastasis at 79%, P < 0.001). There was no significant difference in rate of melanoma-related metastasis for patients treated with plaque radiotherapy versus enucleation.
Conclusion: Large uveal melanoma demonstrates 7-year rate of metastasis at 52%, with generalized increasing risk per 1-mm or 2-mm thickness increments. Extraocular extension was associated with greater metastatic rate, whereas Bruch membrane rupture and macular location demonstrated lower rate.