A case of adult-onset Still's disease complicated by non-Hodgkin's lymphoma.

Left cervical lymphadenopathy developed in a 50-year-old male who had a history of adult-onset Still's disease for the preceding 18 months. Still's disease is characterized by rash, fever, and leukocytosis. Lymphadenopathy has been reported in about 60% of the patients, and most histopathologic studies have shown non-specific reactive hyperplasia. However, in this case, an open biopsy of the cervical node revealed a histology of diffuse large B-cell lymphoma. The B-cell malignant lymphoma that developed may have resulted from a sequential progression of a previous stage of benign lymphoproliferative lesion. Our case suggests that the pathophysiology of adult-onset Still's disease involves the stimulation of lymphoid systems to the point of progression towards lymphoma. Malignant lymphoma should be added to the list of life-threatening complications which, although rare, are associated with this disease.