Clinical Characteristics of UM and Association of Metastasis of Uveal Melanoma with Congenital Oculocutaneous Melanosis in Asian Patients: Analysis of 1151 Consecutive Eyes

Abstract

Purpose: To analyze the clinical characteristics of uveal melanoma (UM) and evaluate the relationship of congenital oculocutaneous melanosis (OCM) to the prognosis of Asian patients with UM.

Design: Retrospective cohort study.

Participants: We included a total of 1151 Asian patients with UM who were managed at the Beijing Tongren Hospital from June 26, 2005, to July 27, 2020.

Methods: I-125 plaque brachytherapy, local resection, thermotherapy, or enucleation.

Main outcome measures: Melanoma-related metastasis and death.

Results: Of 1151 Asian patients with UM, congenital OCM was present in 23 (0.20%). The melanocytosis involved the conjunctiva (78%), sclera (74%), eyelid (70%), face (26%), forehead (2.2%), iris (0.87%), choroid (0.87%), and auricle (0.4%). Univariate analysis of Cox proportional hazards regression model showed that age, tumor thickness, largest tumor basal diameter, and ciliary body involvement were the risk factors for the poor prognosis of Asian patients with UM. By multivariable analysis, the only factor predictive of melanoma-related metastasis and death was the largest tumor basal diameter (hazard ratio [HR], 1.21 [1.11-1.33], P < .001; 1.17 [1.01-1.35], P = 0.033). Probability-of-censoring weighted (IPW) estimation was used to mitigate selection bias due to loss to follow-up. Probability-of-censoring weighted estimation revealed the largest tumor basal diameter and ciliary body involvement were associated with metastasis (HR, 1.29 [1.15-1.45], P < 0.001; HR, 2.64 [1.01-6.90], P < 0.048). During the median follow-up period of 53 (33-67) months, 2 patients with OCM (8.7%) developed melanoma-related metastasis. By using nested case-control design and matched with the factors of age, largest tumor basal diameter, tumor thickness, and ciliary body involvement, Kaplan-Meier survival analysis showed that UM combined with OCM did not increase the risk of melanoma-related metastasis and death (P = 0.68, log-rank test).

Conclusions: The prominent risk for metastasis from UM was the largest tumor basal diameter in Asian patients. Estimation of IPW revealed that the largest tumor basal diameter and ciliary body involvement were the risk factors for UM metastasis. Patients with UM combined with OCM had a similar risk for metastasis compared with those with no OCM.

Keywords: Congenital oculocutaneous melanosis; Metastasis and death; Prognosis; Uveal melanoma.