Orbital lymphomas: a clinicopathologic study of a rare disease.

Objective: To evaluate the clinicopathologic features and prognosis of patients with orbital lymphomas.
Methods: Clinical and pathologic data of 35 patients with biopsy-proven orbital lymphoma diagnosed at a tertiary care hospital from 1992 to 2001 were reviewed. Lymphomas were divided into low-grade and high-grade lymphomas. Survival of patients was compared according to age, gender, disease site, extent of disease, tumor grade, and treatment modality by using log rank test.
Results: Median patient age was 75 years (23-94) and the male-to-female ratio was 1:2.9. Twenty-three patients (66%) were diagnosed with low-grade lymphoma, and 12 patients (34%) were found to have high-grade lymphoma. Among low-grade lymphomas, marginal zone lymphoma (n=6), follicle center cell lymphoma (n= 6), and small lymphocytic lymphoma (n=5) were common entities, whereas diffuse large cell B-cell lymphoma (n=5) was the most common entity in patients with high-grade lymphoma. Disease was clinically localized in 74% of patients at the time of diagnosis. Radiation alone or with chemotherapy was the primary treatment modality in 83% of patients. All except one patient had an objective response to therapy. Over the median follow-up period of 47 months (range, 1.5-141 months), disease recurred in 37% patients who achieved a complete response. The estimated 5- and 10-year survival rates were 64% and 42%, respectively. Overall, 13 (37%) patients died, 6 with high-grade and 7 with low-grade lymphoma. No clinical variable was found to be prognostically significant with respect to survival.
Conclusions: Orbital lymphoma is a disease of the elderly with a female preponderance. It tends to be localized to the orbit at the time of diagnosis and responds well to local or systemic therapy.