Prognostic indicators following enucleation for posterior uveal melanoma. A multivariate analysis of long-term survival with minimized loss to follow-up.

Most previous reports on survival following enucleation for uveal malignant melanoma do not contain cumulative survival rates, do not use a multivariate approach and are liable to a considerable loss to follow-up. In this study, the long-term survival and tumour-related mortality were studied in 340 patients. Archival specimens containing posterior uveal melanomas were initially examined and sectioned by one pathologist. There was no loss to follow-up 6 to 22 years after enucleation. At the end of study, 233 (68.5%) individuals were dead; 137 (40.3%) of melanoma-related causes and 96 (28.2%) of other causes. Melanoma-related deaths appeared from 24 to 6848 days (18 years 8 months) after enucleation. The cumulative 5-year survival proportion based on melanoma-related deaths was 70% and the corresponding 10-year proportion was 56%. Multivariate Cox regression indicated that the largest tumour dimension, cell type, and tumour location all had independent prognostic value, the associated hazard ratios ranged from 1.2 to 1.4, suggesting a moderate increase of the relative risk. Pair-wise comparisons of the parameters indicated that large tumours were more common in the anterior choroid or ciliary body than in the posterior choroid. Similarly, large tumours were more often necrotic, composed of epitheloid cells, or featured extrascleral extension. Tumours with significant scleral invasion or extrascleral extension were more common in elderly patients.