Total lymphoid irradiation (TLI) has been used to treat rheumatoid arthritis (RA) since the 1970s. This study reviews long-term (15-20-year) mortality outcomes of patients treated with TLI for RA at Stanford University Medical Center and compares these outcomes with those in patients treated with disease-modifying antirheumatic drugs (DMARDs).
Fifty-three patients with RA were treated with full-dose TLI at Stanford University Medical Center. All had failed previous therapy with gold salts and penicillamine. One hundred six control patients were selected from the Arthritis, Rheumatism, and Aging Medical Information Systems database and were matched with the patients for age, sex, disease duration, and mean Health Assessment Questionnaire (HAQ) score. Survival was analyzed using Kaplan-Meier methods and Cox proportional hazards regression.
No significant difference in age and sex was found between TLI-treated patients and controls. TLI-treated patients had more education (mean 13.4 years versus 11.8 years; P = 0.016) and received more DMARDs prior to TLI (mean 2.1 versus 1.3; P = 0.0001). TLI-treated patients had lower mean HAQ scores at the time of TLI (2.0 versus 2.4; P = 0.0002). TLI had no significant overall effect on survival in treated patients compared with controls (P = 0.62). The survival curves appeared to cross over at approximately 11 years of followup, with better early survival in the TLI group and better late survival in the control group. There was a total of 25 deaths in the TLI group. There were 45 deaths in the control group, with causes of death available for 20 patients. There were 3 patients with lymphoma and 2 with myelodysplastic syndrome in the TLI group, and none in the control group. The most common cause of death in both groups was infection.
TLI had no significant effect on overall survival, with trends toward higher early mortality in controls and trends toward higher late mortality in TLI-treated patients. Overall, there was no difference in mortality, but it appears that there may have been more lymphoproliferative malignancies in the TLI cohort. We would recommend that TLI be used cautiously for patients with refractory RA in whom the benefits outweigh the risks.