Abstract
Purpose::
Therapeutic concepts in brachytherapy of large uveal melanoma and uveal melanoma near to the optic disc are evaluated.
Methods::
Retrospective analysis of the radiation protocol and the follow up data of patients with uveal melanoma. Patients: total n=approx. 4000, Group (a): study patients: n=35, inclusion criteria: large uveal melanomas (median tumor prominence 7.2 mm) treated with brachytherapy using 106-ruthenium and up to 1500 Gy radiation dose at the outer sclera. Group (b): study patients: n=331, inclusion criteria: uveal melanomas adjacent to the optic disc. Brachytherapy was performed with a notched 106-ruthenium plaque (type COB).
Results::
Group (a): 88.6% (n=31) of the patients included showed a complete regression of the uveal melanoma and the induction of an atrophical radiation scar. In 11.4% (n=4) secondary enucleation had to be performed. Visual acuity in most of the patients was massively deteriorated, in 63% (n=22) the visual acuity was < 0.1. Group (b): In 48.9% (n=162) of the patients included in the study adjunctive treatment was initiated. 11.4% (n=38) needed a second brachytherapy, 36.9% (n=122) needed subsequent transpupillary thermotherapy (TTT (n=69) or photocoagulation (n=53)). Only 3.3% (n=11) of all 331 eyes included in group (b) had to be eventually enucleated. Nearly all patients developed radiation induced optic neuropathy with subsequent visual loss.
Conclusions::
Group (a): Local radiation with increased radiation doses at the outer sclera is a therapeutic option in eye salvaging treatment of large uveal melanomas with an acceptable rate of radiation induced complications if surgical removal (transretinal resection, transscleral resection) was not feasible. Radiation induced necrosis of the sclera did not occur in our series although the radiation thresholds as reported in the literature is exceeded significantly. Group (b): Primary brachytherapy was not enough in half of all cases to destroy the whole tumor. In most patients tumor control was achieved after additional therapy. Atrophy of the optic nerve and loss of vision could not be avoided.
Keywords: tumors • melanoma • uvea