Two patients illustrating lymphoma transition and response to therapy in Sjögren's syndrome.

Two patients with Sjögren's syndrome (SS) who subsequently developed malignant B-cell lymphomas are reported in detail. The first patient had both benign- and malignant-appearing lymphoid infiltrates on the same submandibular gland specimen and was successfully treated with combined chemotherapy and irradiation. The second patient developed cutaneous lymphoid infiltrates difficult to diagnose by light microscopy but containing a monoclonal IgM-Kappa population revealed by immunoperoxidase staining and immunoglobulin gene rearrangement studies. Her lesions resolved rapidly and completely on cyclophosphamide, recurred rapidly when this drug was discontinued, and resolved again on a second course of cyclophosphamide which is currently maintained at 50 mg daily. Both patients are doing well without recurrence two and three years after initial treatment. This clinical experience is presented to emphasize: (1) the clinical use of molecular biologic techniques to define the earliest appearance of malignant transformation in Sjögren's syndrome, and (2) the successful outcome that can be achieved with prompt institution of appropriate treatment. The phenomenon of lymphoma development in SS is discussed with regard to immunoregulatory abnormalities predisposing to malignancy in the setting of autoimmune disease.