Role of radiation therapy in patients with a diagnosis of both systemic lupus erythematosus and cancer

Objective. To determine whether radiation therapy (RT) is denied to patients with lupus and cancer and whether RT causes unusual toxicity in those receiving it. Methods. We included patients with lupus followed at the University of Toronto Lupus Clinic between 1972 and 2001 who had developed cancer. Demographic, clinical, and laboratory information were collected prospectively. Pathologic proof of cancer was obtained. Three radiation oncologists blinded for the diagnosis of lupus, the modalities of cancer treatment, and the hypothesis of the study reviewed patient data independently. They assessed the indication for RT and whether it should be curative or symptomatic. Recommendation for RT was considered when at least 2 of the 3 radiation oncologists concurred. A review of the literature was conducted. Results. Forty cases of cancer in 38 patients were identified. Most frequent cancer sites were breast (8), skin (8), digestive (7), and hematologic (7). Median patient age was 58 years. The radiation oncologists recommended RT in 26 cases, either with a curative (14) or a symptomatic intent (12). Only 4 patients received RT, 3 with a curative intent and 1 with a symptomatic intent. None of these 4 patients developed any unusual toxicity. The literature review did not support the fact that lupus patients do not tolerate RT. Conclusion. Sixty-five percent of our lupus patients with cancer could have received curative or symptomatic RT but only 10% received it. No patient developed any toxicity. RT may be inappropriately withheld from lupus patients with cancer.