Management of choroidal melanomas less than 10 mm in largest basal diameter with a 10-mm ruthenium plaque.

Abstract

To assess tumor control, complications, and vision after brachytherapy for posterior choroidal melanoma <10 mm in largest basal diameter with the 10-mm ruthenium plaque. This was a retrospective cohort study of consecutive choroidal melanomas <10 mm by largest basal diameter in a national ocular oncology service in 1998 to 2010. The median dose was 116 Gy (range, 80-194 Gy) to the apex and 327 Gy (range, 201-824 Gy) to the sclera. The median tumor height and largest basal diameter were 1.9 mm (range, 0.4-5.2 mm) and 7.0 mm (range, 3.3-9.6 mm), respectively. The median distance to disk and foveola was 3.0 mm (range, 0-7.5 mm) and 2.0 mm (range, 0-8.5 mm), respectively. Four recurrences occurred at a median of 1.4 years (range, 0.6-3.1 years) after irradiation. Five-year cumulative incidence of local recurrence was 9% (95% confidence interval [CI], 3-20). Six patients died at a median of 4.2 years (range, 0.28-8.6 years) after treatment, one with evidence of metastases. At 5 years, 57% (95% CI, 31-79), 72% (95% CI, 58-85), and 97% (95% CI, 88-100) of eyes were free of any maculopathy, radiation maculopathy, and optic neuropathy, respectively. Cumulative incidence of developing low vision and blindness were 17% (95% CI, 7-31) and 3% (95% CI, 2-12) at 5 years, respectively. Thickness >3.0 mm, largest basal diameter >7.0 mm, and location ≤ 1.5 mm of foveola were associated with visual loss. Local tumor control and vision outcomes support the use of 10-mm ruthenium plaques in managing smallest choroidal melanomas.