Orbital involvement in chronic lymphocytic leukemia.

In a 68-year-old man with chronic lymphocytic leukemia diagnosed on the basis of peripheral lymphocytosis, marked bilateral exophthalmos developed owing to massive orbital involvement by the disease. At the time there was no lymphadenopathy or evidence of organ infiltration. The response to radiotherapy was excellent. Orbital involvement is rare as an early clinical feature of chronic lymphocytic leukemia but should be considered in the differential diagnosis of bilateral exophthalmos in adults.