Intraocular recurrence of uveal melanoma after proton beam irradiation.

The authors evaluated tumor recurrence as an end point in 1077 uveal melanoma patients treated by proton beam irradiation between 1975 and 1987, with a mean follow-up of 4.0 years. Twenty tumors (1.9%) exhibited definitive growth between 4 months and 66 months after irradiation (median, 19 months): 10 were marginal recurrences, 5 were ring melanomas, 3 were uncontrolled tumors, and 2 were extrascleral extensions. Ten of these eyes were enucleated without further intervention, 2 patients died of metastases soon after the growth was detected, and 8 patients had further conservative therapy. In 5 other patients, tumor growth was suspected but unconfirmed and the eye was enucleated elsewhere; the 5-year probability of local tumor control based on 25 recurrences was 97% +/- 1%. There was a nonsignificant increase in the rate of metastases among patients with documented tumor recurrence (adjusted relative risk, 1.5; 95% confidence interval, 0.66 to 3.4). Results suggest that recurrence of uveal melanomas treated by proton beam therapy is uncommon, but that treatment failure may increase risk of death from metastasis.