Abstract
Purpose :
Orbital lymphoma represents one of the most common orbital tumors, though few studies have analyzed its epidemiological trends. This study uses the Surveillance, Epidemiology, and End Results (SEER) database to investigate the longitudinal trends and survival data of orbital lymphoma in a diverse patient cohort in the United States.
Methods :
The SEER database is a population-based cancer registry that captures 18 population groups in 198 counties, representing about 26% of the U.S. population. Using this database, all cases of malignant primary orbital malignancies from 1973 to 2009 were retrospectively analyzed. Primary outcome measures were disease-specific survival and overall survival rate. Kaplan-Meier survival curves and Cox proportional hazards regression analysis were created for multiple patient and tumor characteristics including gender, year of diagnosis, race, histological subtype, radiotherapy, nodal stage, and age at diagnosis.
Results :
A total of 2,436 patients with primary orbital malignancies were included, of which 1,739 with a diagnosis of orbital lymphoma were selected for further analysis. 54.2% of these patients were female with a median age at diagnosis of 69.0 years. There appears to be a gradual increase in the proportion of orbital malignancies diagnosed as lymphoma over time (Fig 1). Based on Kaplan-Meier survival analysis, patients older than 70 years exhibited worse disease-specific survival compared to patients who were younger. In addition, small B lymphocytic non-Hodgkin lymphoma and marginal zone B cell lymphoma demonstrated superior disease-specific survival compared to diffuse large B cell lymphoma and follicular lymphoma (Fig 2). In a Cox proportional hazards regression analysis, race, histological subtype, radiotherapy, nodal stage, and age at diagnosis were statistically significant covariates in the model.
Conclusions :
This study describes a large cohort of orbital malignancies in a diverse population over the last 37 years and provides valuable information regarding the demographics and epidemiology of orbital lymphoma. Cox proportional hazards analysis identifies several key variables affecting disease-specific survival in these patients. These results augment our knowledge of orbital malignancies, and will improve the ability to counsel patients on disease course and prognosis.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.