[Incidence of metastasis and survival in patients with primary uveal melanoma].

Introduction: Primary uveal melanoma is the most common intraocular malignancy in adults. Almost 50% of patients die from metastatic disease despite successful local treatment. The objective was to estimate the incidence of metastasis and survival in patients with primary uveal melanoma. The second objective was to determine the independent predictors of metastasis.

Methods: A retrospective, observational, analytical study was carried out using an ambidirectional cohort design in patients from Buenos Aires City between January 2003 to January 2020. Patients with uveal melanoma and potential clinical predictors of metastasis were identified. The density of incidence of metastasis and mortality were determined, and survival curves were analyzed (Kaplan Meir) A univariate and multivariate analysis using Cox proportional hazard models was performed.

Results: 143 patients (mean age 57 SD 16) were included. The median thickness was 6.2 mm SD 3.4 mm, the mean tumor diameter was 12.6 mm (SD 3.8). 69.9% of the patients underwent conservative treatment with brachytherapy while 25.9% underwent enucleation. 19.6% presented metastasis, the median time to the event was 26.5 months. The specific mortality due to melanoma was 17.5%. Diameter greater than 12 mm and extension were predictor variables of metastasis in a multivariable model.

Conclusion: Although the median time to the event (metastasis) is 26.5 moths, it could occur many years after local oncological effective treatment. An early diagnosis would allow finding smaller tumors and would improve the prognosis.