Choroidal Melanoma with Ultrasound-Guided Episcleral Brachytherapy: Long-Term Results and Risk of Metastasis

Introduction: The aim of this study was to elucidate the long-term outcomes in patients with choroidal melanoma who received episcleral brachytherapy with 125-I seeds; analyse cause-specific survival (CSS), metastasis-free survival (MFS), and local control; and establish the relationship between tumour size and metastases. Methods: From May 2007 to February 2013, 88 patients classified according to the American Joint Committee on Cancer guidelines underwent ultrasound-guided episcleral brachytherapy with a total prescribed dose of 72.40 Gy to the apex. Results: Among the included cases, 47.7 and 44.3% had a clinical tumour stage of T2 and T3, respectively. With a median follow-up of 84 (range 7-153) months, local control at 5 and 10 years was 100 and 95%, respectively. Among the 88 patients, 9 (10.2%) were enucleated after brachytherapy. Those with T1-T2 and T3-T4 disease had a 10-year CSS of 100 and 87.3%, respectively (p = 0.017). MFS at 5 and 10 years was 100% in those with T1-T2 disease and 92.1 and 83.1% in those with T3-T4, respectively (p = 0.016). Five patients had liver metastases, all of whom had T3-T4 disease. Conclusion: Ultrasound-guided episcleral brachytherapy with 125-I seeds yielded excellent local control for choroidal melanoma, with low complication rates and 90% eye preservation. Given the association between tumour stage and liver metastases, which remain the main cause of death, stricter control should be employed for T3-T4 tumours for the early detection and treatment of relapses.