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Purpose: The aim of this study was to evaluate local tumour control, incidence of radiation-induced glaucoma and associated interventions of sector-based and whole anterior segment proton beam therapy (PBT) for the treatment of iris melanoma., Patients and Methods: We retrospectively analysed the data of 77 patients with iris melanoma who underwent PBT applied as 50 CGE in four daily fractions. Of the patients, 47 received PBT with a circular-shaped collimator and 30 with a conformal sector-shaped target volume. Local control, eye preservation and secondary glaucoma were evaluated., Results: Median follow-up time was 54.9 months. Local tumour control was 100% in patients receiving whole anterior segment irradiation. Two patients developed pigment dispersion in the non-irradiated area after sector-based PBT and received whole anterior segment salvage PBT. The mean volume of ciliary body irradiated was 89.0% and 34.9% for whole anterior segment and lesion-based irradiation, respectively. At the end of follow-up, secondary glaucoma was found in 74.3% of the patients with whole anterior segment irradiation and in 19.2% with sector-based irradiation. Patients with sector-based PBT had a stable visual acuity of logMAR 0.1, while it declined from logMAR 0.1 to 0.4 after whole anterior segment irradiation., Conclusion: We found a significant reduction in radiation-induced secondary glaucoma and glaucoma-associated surgical interventions and stable visual acuity after sector-based irradiation compared with whole anterior segment irradiation. Sector-based irradiation revealed a higher risk for local recurrence, but selected patients with well-circumscribed iris melanoma benefit from applying a lesion-based target volume when treated with sector-based PBT.

Background and Purpose: Proton therapy for uveal melanoma provides high-conformal dose application to the target volume and, thus, an optimal saving of the organs at risk nearby. Treatment planning is done with the model-based treatment-planning system EYEPLAN. Tumor reconstruction is based only on a fundus composite, which often leads to an overestimation of the clinical target volume (CTV). The purpose was to exploit MRI on trial in a proton therapy-planning system by using the novel image-based treatment-planning system OCTOPUS., Patients and Methods: Ten patients with uveal melanomas received both a high-resolution planning CT and MRI of the eye. MR examinations were made with an eye coil. EYEPLAN requires eye geometry data for modeling, and tantalum marker clips for submillimeter positioning and additional information from ultrasound and 3-D imaging. By contrast, OCTOPUS provides the full integration of 3-D imaging (e. g., CT, MRI). CTVs were delineated in each slice. For all patients, CTVs (EYEPLAN vs. OCTOPUS) were compared intraindividually., Results: OCTOPUS planning led to a mean reduction of the target volume by a factor of 1.7 (T1-weighted [T1w]) and 2.2 (T2w) without compromising safety. The corresponding field size could be scaled down on average by a factor of 1.2 (T1w) and 1.4 (T2w), respectively., Conclusion: Compared with the conventional EYEPLAN, MRI-based treatment planning of ocular tumors with OCTOPUS could be a powerful tool for reducing the CTV and, consequently, the treatment volume and the field size. This might be translated into a better patient compliance during treatment and a decreased late toxicity.

Background and Purpose: Proton and stereotactic radiotherapy with photons (SRT) are both used to treat choroidal melanomas in proximity to optic disk and fovea centralis, a situation where plaque therapy is prone to complications. A comparative treatment- planning study was done to assess the capability of both modalities to preserve vision., Patients and Methods: In ten patients treated with 68-MeV protons, SRT with 6-MV photons was planned. Structures most important for visual acuity (fovea and optic disk, optic nerve) were contoured identically for both therapies. Safety margins of 1.5 mm for proton therapy were reduced to 1.0 mm for SRT., Results: Proton-beam therapy was superior in eight of ten situations, and this result did not differ significantly by changes in the weighting of the different parameters analyzed., Conclusion: When dose deposition to those structures most important for the preservation of vision is taken into account, under the conditions examined proton therapy offers an advantage in the majority of the patients evaluated.

Background and Purpose: In June 1998, proton-beam therapy of ocular tumors started at the Hahn-Meitner Institute Berlin, Germany. The purpose of the present study is to evaluate treatment outcome for uveal melanomas., Patients and Methods: 245 consecutive patients with primary melanoma of the uvea were treated from June 1998 to April 2003 with a 68-MeV proton beam. In 96.2% of all patients, a uniform fractionation scheme was applied: single dose 15 CGE (cobalt gray equivalent), total dose 60 CGE on 4 consecutive days. Follow-up is available in 229 patients., Results: At the time of median follow-up (18.4 months), local control is 96.4% and 95.5% at 3 years. Eye retention rate is 92.6% at 20 months (median follow-up) and 87.5% at 3 years., Conclusion: Proton-beam irradiation of uveal melanomas at the Hahn-Meitner Institute after the first 5 years of its initiation reveals local tumor control and eye retention rates in the range of other centers with larger experience. Delivering high treatment quality in hadron therapy from the beginning has been achieved.