Prognostic factors of choroidal melanoma in Slovenia, 1986-2008

Choroidal melanoma is the most common primary malignancy of the eye, which frequently metastasizes. The Cancer Registry of Slovenia reported the incidence of choroid melanoma from 1983 to 2009 as stable, at 7.8 cases/million for men and 7.4/million for women. The aim of the retrospective study was to determinate the prognostic factors of survival for choroidal melanoma patients in Slovenia.

From January 1986 to December 2008 we treated 288 patients with malignant choroidal melanoma; 127 patients were treated by brachytherapy with beta rays emitting ruthenium-106 applicators; 161 patients were treated by enucleation.

Patients with tumours thickness < 7.2 mm and base diameter < 16 mm were treated by brachytherapy and had 5- and 10-year overall mortality 13% and 32%, respectively. In enucleated patients, 5- and 10-year mortality was higher, 46% and 69%, respectively, because their tumours were larger. Thirty patients treated by brachytherapy developed local recurrence. Twenty five of 127 patients treated by brachytherapy and 86 of 161 enucleated patients developed distant metastases. Patients of age ≥ 60 years had significantly lower survival in both treatment modalities. For patients treated by brachytherapy the diameter of the tumour base and treatment time were independent prognostic factors for overall survival, for patients treated by enucleation age and histological type of tumour were independent prognosticators. In first few years after either of treatments, the melanoma specific annual mortality rate increased, especially in older patients, and then slowly decreased.

It seems that particularly younger patients with early tumours can be cured, whereby preference should be given to eyesight preserving brachytherapy over enucleation.