Lymphoid irradiation in intractable rheumatoid arthritis. A double‐blind, randomized study comparing 750‐rad treatment with 2,000‐rad treatment

Abstract
Twenty patients with intractable rheumatoid arthritis were treated with 750‐rad or 2,000‐rad lymphoid irradiation in a randomized double‐blind comparative study. Over a 12‐month followup period, there was a significant improvement in 4 of 7 and 6 of 7 standard parameters of disease activity following treatment with 750 rads and 2,000 rads, respectively. Transient, short‐term toxicity was less frequent with the lower dose. In both groups, there was a sustained peripheral blood lymphopenia, a selective depletion of T helper (Leu‐3a+) lymphocytes, and reduced in vitro mitogen responses. These changes did not occur, however, in synovial fluid. These results suggest that 750‐rad lymphoid irradiation is as effective as, but less toxic than, that with 2,000 rads in the management of patients with intractable rheumatoid arthritis.