Abstract

The records of 265 consecutive patients with juxtapapillary choroidal melanoma were reviewed and a statistical non-randomised retrospective study was performed to evaluate the risk for metastasis and compare the survival rate of patients treated with plaque radiotherapy or enucleation. To obtain sufficient overlap between the enucleation and plaque radiotherapy, the statistical analysis was limited to an adjusted subgroup of 127 patients who met eligibility criteria for plaque radiotherapy and who had a minimum of 3 years of follow up after treatment. In the adjusted subgroup of 127 patients, 92 patients (72%) were initially treated with enucleation and 35 (28%) with plaque radiotherapy. In both univariate and multivariate logistic analysis models, the age of the patient (> 50 years), tumour thickness (> 3 mm), and treatment by age interaction were found to be significant factors for development of distant metastasis. In patients younger than 50 years, the method of treatment (enucleation versus plaque radiotherapy) did not significantly affect the risk of metastasis. For those older than 50 years, there was a non-significant trend for patients in the enucleation group to be at a higher risk for metastasis than those in the plaque group. In the enucleation group, patients older than 50 years had a significantly higher incidence of distant metastasis than those younger than 50 years. In the plaque radiotherapy group, there was no significant higher incidence of metastasis in patients younger than 50 years than in those older than 50 years. When a Cox proportional hazards model was used to evaluate the survival rate, there was the same statistically significant effect of treatment by age interaction as was found in the multivariate logistic model on survival time. Moreover, there was a significant effect of treatment by tumour thickness interaction on survival time. Patients in the enucleation group had a better survival rate when the thickness of the tumour was less than 3 mm compared with a tumour of more than 3 mm. There were no apparent effects of tumour thickness on survival for patients treated with plaque radiotherapy. From these results, the authors currently recommend plaque radiotherapy as a viable option to enucleation in patients with juxtapapillary choroidal melanoma.