Stereotactic radiotherapy of uveal melanoma: The Dunedin Experience

Abstract

Uveal melanoma is a rare disease causing significant mortality. Metastatic disease - for which there is no treatment - often occurs before the primary tumor is diagnosed. In addition to enucleation, there are many globe-sparing ways of treating the primary tumour. Fractionated stereotactic radiotherapy is one such treatment, delivering a homogenous dose of radiation to the tumour and allowing normal tissue the chance to recover between fractions.

The aim of this thesis was to evaluate the effectiveness of fractionated stereotactic radiotherapy for the treatment of uveal melanoma in the New Zealand population. The main outcome measurements were local tumour control, visual acuity, radiogenic side effects and metastatic death. A retrospective audit of clinical notes was performed on all patients with uveal melanoma treated with fractionated stereotactic radiotherapy in Dunedin, New Zealand, from July 2001 to December 2007. All twenty-seven patients treated during this period were included. Local control was achieved in all patients. Three patients required secondary enucleation for intractable pain, recurrent vitreous cavity haemorrhage, and recurrent retinal detachment. Visual acuity deteriorated in eighteen of the remaining twenty-four patients (75%), and mean Snellen acuity dropped from 6/6 at baseline to 6/21 at final follow-up. Eight patients developed radiation retinopathy, one patient developed optic neuropathy, and two patients developed neovascular glaucoma. At final follow-up, three patients were known to have died of metastatic disease. Fractionated stereotactic radiotherapy is an eye-sparing treatment option for patients with uveal melanoma. Data from this study supports international literature that this is a useful addition to the treatment armamentarium for this cancer.