Clinical Features, Metastasis, and Survival in Patients Younger Than 21 Years With Posterior Uveal Melanoma.

Importance: Given the rarity of posterior uveal melanoma in patients younger than 21 years, reporting clinical experience in this area has relevance.

Objective: To describe the baseline clinical features, treatment, and clinical course of a group of patients younger than 21 years who have primary posterior uveal melanoma.

Design, Setting, And Participants: This retrospective descriptive case series of patients younger than 21 years who have a primary choroidal or ciliochoroidal melanoma was conducted at a single-center subspecialty referral practice. Patients in the relevant age group who were treated in a single practice between July 1980 and December 2013 were included; clinical data collected through December 2017 were captured to permit adequate follow-up time in all cases.

Main Outcomes And Measures: Conventional descriptive statistics of relevant clinical variables (eg, demographic, tumor, treatment, and outcome variables) of each patient were recorded. Actuarial metastasis-free and overall survival curves were computed and plotted, as was a postdetection survival curve of patients who developed metastasis during available follow-up.

Results: Of 2265 patients with posterior uveal melanoma encountered by the authors during the study interval, 18 (0.8%) were younger than 21 years when diagnosed and treated. Ten were female and 8 male, and the mean (SD) age was 16.6 (4.2) years. Through available follow-up, 8 of these patients had developed metastatic uveal melanoma (44%). All 8 died of metastasis. Actuarial survival analysis showed that the cumulative probability of metastatic death in this group exceeded 50%. The median overall survival time after treatment of the primary intraocular tumor was 11.9 (95% CI, 7.3-16.5) years. The median survival time after detection of metastasis in the 8 patients who developed metastasis was 2.3 months (95% CI, 0.0-5.2) months.

Conclusions And Relevance: Posterior uveal melanoma in patients younger than 21 years appears to have a similar if not worse prognosis than patients with PUM in the population overall. Owing to the later onset of metastasis observed, patients younger than 21 years should continue to have surveillance tests for more than 10 years after treatment.