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Background To report on local tumour control, eye preservation and visual outcome after ruthenium-106 brachytherapy for uveal melanoma. Methods Medical records of 143 eyes with uveal melanoma, treated by ruthenium-106 brachytherapy between 1997 and 2012 at one single centre, were included. Primary outcome measures were local tumour control, eye preservation and visual outcome. The influence of patient, tumour and treatment parameters on outcome was analysed by time to event analysis and competing risk regression. Results The median overall follow-up was 37.9 months. Tumour control: recurrent tumour growth was observed in 17 patients. The estimated local tumour recurrence rate at 12, 24 and 48 months after irradiation was 3%, 8.4% and 14.7%, respectively. The only significant risk factors for tumour recurrence were age (p=0.046) and reduced initial visual acuity (VA, p=0.045). No significant difference could be shown for tumour size or tumour category (T1-T2 vs T3-T4), and for any other tumour or treatment parameters (including combined transpupillary thermo-therapy (TTT)). Eye preservation: The likelihood of keeping the eye 12, 24 and 48 months after irradiation was 97.7%, 94.7% and 91.8%, respectively. Most significant risk factors for secondary enucleation were initial VA (p<0.001), tumour height (p=0.002) and tumour category (p=0.015). Vision The chances of keeping VA of 20/200 or better at 1, 2 and 5 years after treatment were 86.4%, 80.8% and 61.7%, respectively. Patients receiving sandwich-TTT showed significantly worse visual outcomes. Conclusions Ruthenium-106 brachytherapy appears to be a useful treatment regarding tumour control, eye preservation and visual function. Adjunct sandwich therapy resulted in worse visual outcome. [ABSTRACT FROM AUTHOR]

Purpose The Collaborative Ocular Melanoma Study (COMS) established iodine-125 (I-125) plaque brachytherapy for eye preserving treatment of medium-sized choroidal melanomas in the United States. Eye Physics I-125 plaque treatment modeled with Plaque Simulator (PS) software yields similar results to COMS. Herein, we report results from a series of 15 patients treated with ruthenium-106 (Ru-106) plaque brachytherapy using PS pretreatment modeling for plaque localization and dosimetry. Methods and Materials Fifteen patients with medium-sized choroidal melanomas (2.84–5.5 mm in apical height and a basal diameter of 7.8–12.6 mm) treated with ruthenium brachytherapy from 2003 to 2005 were evaluated retrospectively. Baseline and followup data were evaluated for tumor height, best corrected visual acuity, radiation retinopathy, radiation optic neuropathy, postradiation cataract formation, diplopia, and ptosis. Tumor response for both Ru-106 and I-125 plaques planned using the same PS pretreatment modeling was evaluated and compared. Results Isotope-specific radiation profiles were compared, and rates of local treatment failure (0%), optic neuropathy (6.7%), retinopathy (20%), and cataracts (33%) were evaluated. Five year–treated tumor heights were approximately 0.61 ± 0.29 (I-125, n = 16) and 0.53 ± 0.17 (Ru-106, n = 6) of their heights at diagnosis. Conclusions This patient subset had background characteristics very similar to those of the COMS and patients treated at our institution with I-125 plaques. Treatment response was equivalent although radiation complications occurred slightly less frequently in the Ru-106 group compared with those treated with I-125. Image-guided three-dimensional pretreatment modeling for plaque localization and dosimetry seems to work equally as well for Ru as for I-125 plaques and justifies more extensive investigation. [ABSTRACT FROM AUTHOR]

An effective and simple process for the isolation of 106Ru from high-level liquid wastes was developed. Radioactive ruthenium was oxidized by H 5IO 6 in HNO 3 solution and was extracted to CCl 4 phase in the form of RuO 4. In order to obtain ruthenium in the suitable form for production of brachytherapy sources, RuO 4 in organic phase was reduced and re-extracted to aqueous phase. The efficiency of extraction of 103Ru to organic phase was 86 %, re-extraction to aqueous solution was near 100 %, so the overall recovery of 103Ru is estimated at more than 80 %. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To evaluate long-term outcomes of eye-conserving treatment using Ruthenium-106 plaque brachytherapy with or without transpupillary thermotherapy (TTT) for small to intermediate size choroidal melanomas. Methods: Outcomes of 425 consecutive patients were analysed. The median basal tumour diameter was 10.9mm (range 4.8–15.9mm), and the median apical height 4.2mm (range 1.2–9.3mm). Brachytherapy doses ranged from 400 to 600Gy with TTT (86%), or from 600 to 800Gy without TTT (14%), specified at the scleral surface. Kaplan–Meier survival curves, log-rank tests and Cox regression analysis were used for analysis. Results: Median follow-up was 50months. Five-year actuarial local control was 96%. Five-year overall and metastases-free survival rates were 79.6% and 76.5%. Prognostic factors for metastasis-free survival were peripheral location (p =0.02) and smaller basal diameter (p <0.001). No dose effect relationships were found. Radiation side effects were frequent, with 2- and 5-year rates free of radiation complications of 60% and 35%. Five-year enucleation rate was 4.4% (10 for local recurrence, 7 for complications). Cosmetic and functional (visual acuity >0.10) eye preservation rates were 96% and 52% at 5years. Conclusions: Ruthenium-106 brachytherapy for choroidal melanoma provides excellent rates of local control and eye preservation. [Copyright &y& Elsevier]

Abstracts: Concave eye applicators with 90Sr/90Y and 106Ru/106Rh beta-ray sources are usually used in brachytherapy for the treatment of superficial intraocular tumors as uveal melanoma with thickness up to 5mm. The aim of this work consisted in using the Monte Carlo code MCNPX to calculate the 3D dose distribution on a mathematical model of the human eye, considering 90Sr/90Y and 160Ru/160Rh beta-ray eye applicators, in order to treat a posterior uveal melanoma with a thickness 3.8mm from the choroid surface. Mathematical models were developed for the two ophthalmic applicators, CGD produced by BEBIG Company and SIA.6 produced by the Amersham Company, with activities 1mCi and 4.23mCi respectively. They have a concave form. These applicators' mathematical models were attached to the eye model and the dose distributions were calculated using the MCNPX ⁎F8 tally. The average doses rates were determined in all regions of the eye model. The *F8 tally results showed that the deposited energy due to the applicator with the radionuclide 106Ru/106Rh is higher in all eye regions, including tumor. However the average dose rate in the tumor region is higher for the applicator with 90Sr/90Y, due to its high activity. Due to the dosimetric characteristics of these applicators, the PDD value for 3mm water is 73% for the 106Ru/106Rh applicator and 60% for 90Sr/90Y applicator. For a better choice of the applicator type and radionuclide it is important to know the thickness of the tumor and its location. [Copyright &y& Elsevier]