Natural Killer T-Cell Lymphoma of the Orbit: An Evidence-Based Approach.

Natural killer T-cell lymphoma (NKTCL) is a rare and aggressive condition with a high mortality rate. It is most commonly seen in the nasal sinuses, generally affecting the orbit by direct extension. Primary orbital NKTCL is even more rare, with only a few published cases with occasional secondary nasal involvement. This malignancy can present as a "masquerade syndrome," delaying proper diagnosis and treatment. Biopsy is required for diagnosis, which shows specific histopathological characteristics. Radiation and chemotherapy are the mainstay of treatment. Newer chemotherapies show improved prognosis.