Ruthenium-106 plaque brachytherapy for symptomatic vasoproliferative tumours of the retina

Abstract

Aim: To investigate the safety and efficacy of beta ray brachytherapy in treatment of vasoproliferative tumours of the retina (VTR).

Methods: 35 consecutive patients with symptomatic VTR were treated with a ruthenium-106 ((106)Ru) plaque. Three tumours had been treated previously (two with cryotherapy; one with transpupillary thermotherapy). 32 VTR (91.4%) were located in the lower half of the retina and all of them were found between the mid-periphery and the ora serrata. The mean tumour thickness was 2.8 mm. An exudative retinal detachment was present in 25 eyes (71.4%) and in 15 cases (42.9%) hard exudates were found in the macula. The major symptom was loss of vision (77.1%).

Results: Brachytherapy was well tolerated by every patient. The mean applied dose was 416 Gy at the sclera and 108 Gy at the tumour apex. In all but four eyes (88.6%), it was possible to control the VTR activity. The median follow up time was 24 months. Three of the above mentioned four eyes with treatment failure had had secondary glaucoma before therapy. There was no case of radiation induced neuropathy or retinopathy. Cataract surgery was necessary for five patients. The development of epiretinal gliosis was the most common event during follow up (n = 10, 28.6%). The mean visual acuity decreased slightly (0.33 before and 0.29 after brachytherapy). Multivariate analysis showed that the presence of macular pathology before treatment was associated with a 6.1-fold risk of vision of 0.25 or better (p = 0.03).

Conclusions: beta ray brachytherapy with (1106)Ru plaques was able to control the activity of VTR and retain vision. Cases with secondary glaucoma before treatment had a very poor prognosis.