The aim of this study was to evaluate metastatic latency and survival after the occurrence of
metastases in patients with choroidal/ciliary body
melanoma treated with
proton therapy. This was a retrospective cohort study. All consecutive patients with choroidal/ciliary body
melanoma treated with
proton therapy between 1991 and 2010 were included. Overall survival, specific survival (SS), local recurrence-free interval, and
metastasis-free interval (MFI) were calculated. There were 508 patients. The mean follow-up was 239.4 months. Overall survival and SS rates were 57.2 and 67.6%
at 10 years. Pre-equatorial
tumor location, advanced
tumor stage, and initial exudative
retinal detachment were associated independently with SS. Thirty-three percent of the patients (n = 169) had
metastases. Local recurrence-free interval and MFI were 91.3 and 65.7%
at 10 years, respectively. MFI was shorter in pre-equatorial, large
tumors, and/or
tumors with exudative
retinal detachment. After the occurrence of
metastases, the median survival time was 1.25 years and survival probabilities were 62.1% at 1 year, 26.0% at 2 years, and 6.0% at 5 years. Except for age, none of the baseline clinical factors was associated with survival after
metastasis occurrence. SS after
metastasis occurrence was longer for
metastasis occurring more than 10 years after
tumor diagnosis (P =0.010). Death after
metastasis is independent of initial
tumor characteristics. Small
tumors still have a risk for
metastases after 10 years. Thus, lifelong follow-up is necessary for
uveal melanoma patients. Larger series of metastatic patients are needed to evaluate aggressive
multimodal treatments of
metastases. Death after
metastasis is independent of the initial
tumor characteristics. Small
tumors contraintuitively have a long-life risk of
metastases. MFI is associated independently with pre-equatorial location,
tumor stage, and
retinal detachment.