MLPA of choroidal melanoma

Abstract

Abstract Purpose To determine the genotypic profiles of choroidal melanomas using multiplex ligation‐dependent probe amplification (MLPA) and to correlate findings with clinical and pathological features and metastatic death. Methods DNA samples from 452 choroidal melanomas were analyzed with MLPA evaluating 31 loci on chromosomes 1, 3, 6 and 8. The MLPA results were correlated with survival predictors and wiht metastatic death. Results The patients (194 female; 258 male) had a median age of 59.4 years and a median follow‐up of 1.89 years. Metastatic death occurred in 47 patients, correlating most strongly with concurrent chromosomes 3 losses and chromosome 8q gains (Logrank analysis, p<0.001). Many small choroidal melanomas with a basal diameter of less than 10mm showed only chromosome 3 loss or chromosome 8q gain or none of these, suggesting that their tumour was 'pre‐lethal' at the time of ocular treatment. Conclusion MLPA analysis of choroidal melanoma is predictive of metastatic death and, therefore, clinically useful. The findings of this study are most consistent with evolutionary clonal abnormality, suggesting that timely treatment prevents the metastatic genotype and metastatic spread in a proportion of patients.