2,000-centiGray total lymphoid irradiation for refractory rheumatoid arthritis.

Because toxicity with the use of 3,000 centiGray (cGy) of total lymphoid irradiation (TLI) was observed in an earlier study, 2,000-cGy treatments were delivered in a 2-portal format to 7 patients and in a modified 3-portal fashion to 6 patients, as part of a randomized, investigator-blinded trial of TLI treatment for refractory rheumatoid arthritis. Analysis of combined data from the 13 patients revealed statistically significant improvement in 5 clinical indicators of disease activity at the end of TLI and 6 and 12 months later, accompanied by T4-specific immunosuppression. Management considerations resulted in the introduction of prednisone therapy in 5 patients, methotrexate in 4, and azathioprine in 1 during the interval of 8-12 months post-TLI. Herpes zoster occurred in 5 patients prior to the initiation of this additional therapy. These data indicate that, in patients with rheumatoid arthritis, a TLI dose of 2,000 cGy is sufficient to produce measurable benefit that lasts for 6 months, and that the improvement can be maintained at 12 months by the use of prednisone and methotrexate.