We report the case of a 33-year-old HIV-seropositive male who had a large c
ell Epstein-Barr virus-associated non-Hodgkin's orbital lymphoma. A thoroug
h medical examination enabled us to find on thoracic CT-scan a mediastinal
lymph node involvement as large as 18 cm in diameter. The regression of the
tumor was dramatic under chemotherapy with complete disapearance of the tu
mor and no recurrence was found after more than 21 months follow-up. We dis
cuss the differential diagnosis with orbital infection.