Radiotherapy of iris melanoma

Abstract

SummaryIris melanomas represent 2 to 3% of uveal melanomas. Conservative management is often possible, with either excision of the tumor or irradiation. Proton beam irradiation for iris melanoma is used since several years, for selected small circumscribed iris melanomas. The results are excellent in terms of local control and eye preservation. The main side effect is cataract formation (45%). Progressively larger tumors have been treated with whole anterior segment irradiation (large tumors or lesions associated with extensive pigment dispersion or iridocorneal angle invasion). Local control is also excellent in this setting. For these larger lesions side effects consisting in corneal alterations and glaucoma are frequent than for localized lesions, especially if there was high ocular pressure anterior to the treatment. Glaucoma, can be challenging to treat leading to vision loss. For all patients the survival is excellent. Proton beam irradiation allows the treatment and avoids surgery of small circumscribed iris melanomas with very little side effects and excellent local tumor control. For larger, not resectable lesions, it allows ocular preservation with good local control, corneal alterations and glaucoma are frequent.