Radiotherapy of unilateral choroidal metastasis: unilateral irradiation orbilateral irradiation for sterilization of suspected contralateral disease?

Radiotherapy is the highly effective standard in the treatment of choroidal metastasis. Visual acuity can be stabilized or increased in about 70-80% o f eyes treated, thus prevailing the quality of life in these worse prognost ic patients. In about 30-40% bilateral macroscopic disease is found at diag nosis. The best treatment for unilateral metastasis remains controversial: unilateral or bilateral irradiation for sterilization of suspected contrala teral metastasis or unilateral irradiation without irradiation of the contr alateral choroidea. In the analysis of a prospective study (ARO 95-08) 35 o ut of 50 patients with choroidal metastasis had unilateral disease and rece ived unilateral irradiation with a lateral field using 6 MeV-photons (40 Gy in 20 fractions) without sparing the contralateral choroidea. Therefore th e posterior contralateral choroidea received 50-70% of the total dose (20-2 8 Gy) for suspected micrometastasis. None of these patients developed contr alateral choroidal metastasis during the median follow up time of 11.5 mont hs. A unilateral field with 40 Gy for unilateral choroidal metastasis witho ut sparing the contralateral choroidea seems to be effective in destroying contralateral micrometastasis with a lower risk of late side effects compar ed with bilateral fields. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.