Posterior uveal melanoma treated with I-125 brachytherapy or primary enucleation

To study the incidence, clinical findings, and tumour characteristics of posterior uveal melanoma in Western Norway, and to report the results of a consistent treatment strategy (I-125 brachytherapy or primary enucleation) over a 13-year period.

The clinical records of all patients with posterior uveal melanoma referred between January 1993 and December 2005 were reviewed. Clinical data, radiation parameters, visual outcome, and mortality were analysed in a dedicated database.

The study included 111 consecutive patients. The annual age-adjusted incidence (per million population) of posterior uveal melanoma was 8.5 for women and 8.9 for men. Fifty-six patients underwent I-125 brachytherapy, 52 were enucleated, and three received no treatment. The median follow-up time was 36 months (mean, 52 months; range, 2 months to 13 years). In the brachytherapy group, two eyes were enucleated owing to tumour recurrence and two because of neovascular glaucoma. A visual acuity of 0.1 or better, present in 87% of the patients before brachytherapy, was retained in 40% after a median follow-up of 61 months. After brachytherapy, the 5- and 10-year melanoma-specific mortality rates were 13.4 and 23.8%, respectively. The corresponding mortality rates for patients treated with primary enucleation were 49.5 and 49.5%.

After brachytherapy, many patients lost useful vision due to radiation-induced complications. The probability of retaining the eye was high and only two patients experienced recurrent tumour growth. The mortality rates compare well with published series, and the differences in tumour size explain the difference in mortality between the two treatment groups.