Ocular adnexal lymphomas: five case presentations and a review of the literature

The ocular adnexal lymphomas represent the malignant end of the spectrum of lymphoproliferative lesions that occur in these locations. The Revised European and American Lymphoma (REAL) Classification and the new World Health Organization Classification of Tumors of Hemopoietic and Lymphoid Tissues are the most suitable for subdividing the ocular adnexal lymphomas, whereby the extranodal marginal zone B-cell lymphoma represents the most common lymphoma subtype. This review is based on five cases subtyped according to the above classifications-three "typical" lymphomas (an extranodal marginal zone B-cell lymphoma, a diffuse large cell B-cell lymphoma arising from an extranodal marginal zone B-cell lymphoma, and a follicular lymphoma) and two "atypical" lymphomas (a non-endemic Burkitt lymphoma in an immune competent elderly patient, and a primary Hodgkin lymphoma of the eyelid) of the ocular adnexa. Management of patients with ocular adnexal lymphomas includes a thorough systemic medical examination to establish the clinical stage of the disease. The majority of patients with ocular adnexal lymphoma have stage IE disease. Current recommended therapy in stage IE tumors is radiotherapy, while disseminated disease is treated with chemotherapy. Despite usually demonstrating an indolent course, extranodal marginal zone B-cell lymphomas are renowned for recurrence in extranodal sites, including other ocular adnexal sites. Long-term follow-up with 6-month examinations are therefore recommended. Major prognostic criteria for the ocular adnexal lymphomas include anatomic location of the tumor; stage of disease at first presentation; lymphoma subtype as determined using the REAL classification; immunohistochemical markers determining factors such as tumor growth rate; and the serum lactate dehydrogenase level.