Clinical and histopathological prognostic factors in uveal melanoma in a large Spanish series of enucleated eyes.

Purpose: To analyze clinical and histopathological prognostic factors and overall and specific survival after enucleation in a Spanish cohort diagnosed with uveal melanoma.

Methods: A prospective analysis was performed in a single-center case series of 138 patients with posterior uveal melanoma seen in the Adult Intraocular Tumour Unit at the University Clinical Hospital of Valladolid and treated by enucleation as the primary treatment between January 2006 and December 2021. Kaplan-Meier and Cox regression analyses were performed to identify prognostic factors.

Results: Mean follow-up time was 54 months. Mean overall and melanoma-specific survival were 119 months (95% CI: 103.82-133.92) and 133 months (95% CI: 118.52-147.90) respectively. In univariate analysis of clinical parameters, only scleral extension was associated with poorer survival (p < 0.001). The histopathological characteristics associated with poorer survival were epithelioid cell type (p = 0.021), high Ki-67 expression (≥15%; p = 0.037), vortex vein invasion (p < 0.001), emissary canal invasion (p = 0.005), extrascleral extension (p = 0.001), and low percentage of necrosis (<10%; p = 0.015). In multivariate analysis, scleral extension (p = 0.008) and vortex vein invasion (p = 0.001) were associated with poorer overall survival.

Conclusion: Spanish population has different racial characteristics to those of Anglo-Saxon cohorts in which uveal melanoma has been studied previously and shows a higher specific survival rate. Classic histopathological features have been confirmed as prognostic factors, but further studies should be performed to evaluate genetic and molecular factors to improve the prediction of survival in enucleated uveal melanoma patients.