Global incidence and prevalence of malignant orbital tumors

Purpose: Aims to provide an overview of the contemporary epidemiology of malignant orbital tumors by analyzing population-based incidence patterns across various regions worldwide. Methods: In this article, we retrieved orbital malignancy data from the MEDLINE database and analyzed the incidence and prevalence of orbital malignancies worldwide. We performed the literature search by searching on the Mesh terms for malignant orbital tumors (''orbital'', ''tumor'', ''lymphoma'', ''malignant'', ''cancer'', ''incidence'', and ''epidemiology''). All included studies were published between 1993 and 2023 and were written in English. Results: Ocular or ophthalmic lymphoma most frequently occurred in the orbit, with a prevalence ranging from 47% to 54%. The incidence of malignant orbital tumors was increasing in the USA (2.0 per million (1981–1993), Netherlands (0.86 (1981–1985) to 2.49 (2001–2005) per million) and South Korea (0.3–0.8 per million (1999–2016)), respectively. Ophthalmic lymphoma which includes orbit lymphoma was increasing in Canada (0.17–1.47 per million (1992–2010)), Denmark (0.86 per million (1981–1985) to 2.49 per million (2001–2005)), respectively. Conclusions: The predominant primary malignant orbital tumor in adults was lymphoma. Ocular or ophthalmic lymphoma most frequently occured in the orbit. The limited data available suggested an increasing trend in the incidence of malignant orbital tumors in each country included, which were mainly attributed to the increase in lymphoma. Generally, incidence rates were found to increase with advancing age, with no difference between males and females.