Stereotaxic precision irradiation of large uveal melanomas with the gamma knife

Abstract

We report our experience with stereotactic radiosurgery using the Gamma-knife in large uveal melanoma unsuitable for brachytherapy (Ru106). We treated 35 patients (16 male, 19 female; age: median 59 years (95% Confidence interval (CI): 31-84 years; 18 right eyes, 17 left eyes). 7 tumors were located juxtapapillary, 16 tumors were located in the mid-periphery and 12 tumors were located in the ciliary body, The localization and/or the dimension of the tumors did not allow for radiation brachytherapy (Ru106). All patients underwent regular clinical, echographical and neuroradiological follow-up examinations. The follow-up time was median 12 months (95% CI: 4-20 months). A local tumor control defined as either continuous tumor regression or stopping of tumor progression was achieved in 34 (97%) of the 35 treated patients within the observation period. The eye of one patient was enucleated due to tumor regrowth. Maximum apical tumor height according to standardized A-scan before treatment was median 9.1 mm (95% CI: 3.2-13.9 mm) and after treatment median 6.4 mm (95% CI: 2.1 bis 11.9 mm). The difference was statistically highly significant (p < 0.001, one-tailed paired t-test). Our results in 35 patients indicate that radiosurgery using the Gamma-knife is beneficial in retaining the eyes of patients with large uveal melanomas that are not suitable for brachytherapy (Ru106).