Small Choroidal Melanoma: Outcomes After Surveillance Versus Immediate Treatment

To quantify potential loss (loss of vision) and gain (freedom from metastasis) in patients with small choroidal melanoma treated after a period of surveillance to document growth.

A total of 167 patients with small choroidal melanoma (size: 5.0-16.0 mm in largest basal diameter and 1.0-2.5 mm in height) were identified: 42 treated after surveillance (documented growth) and 125 treated immediately. A prediction model was applied to each patient in the immediate treatment group to obtain the predicted risk of melanoma (high risk vs low risk). Potential loss (loss of vision) and gain (freedom from metastasis) were compared between the low-risk immediate treatment group and those treated after surveillance.

By using the optimal cut point (0.60; 95% confidence interval: 0.37-0.61) of predicted risk for small choroidal melanoma (sensitivity: 0.74, specificity: 0.95), we identified 94 (75%) patients as high risk (score: ≥0.6) and the remaining 31 (25%) as having low-risk melanoma (score: <0.6). Over a median follow-up of 34.6 months, 5 developed metastasis (high risk = 4, low risk = 1) compared with 1 patient in the surveillance group. Initial visual acuity and loss of <15-letter visual acuity were not significantly different at 36 months between the low-risk patients immediately treated and those treated after surveillance (81% vs 83%), respectively.

Low-risk choroidal melanoma identified by the prediction model can be labeled as an indeterminate melanocytic tumor. Such patients can be managed by surveillance to document growth before receiving vision-threatening treatment without increased risk of metastatic death. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.