This is a rare condition most often associated with one or another form of immune defect. In most cases of grade II and III disease, monoclonal rearrangement of immunoglobulin genes is confirmed. The tumor cells are positive for Epstein-Barr virus.
The disease is characterized by nodules, often in the lungs, but also occurring in other extra nodal organs such as the brain, kidneys, liver, and skin. Histopathologically, the lymphoma is graded from I to III. General symptoms are common.
The disease course varies with a median survival time of under 2 years.
Disease in grade I and II may respond to interferon. Combination chemotherapy should be given for grade III disease.