Antiphospholipid syndrome associated with immunotherapy for patients with melanoma

Abstract

BACKGROUND: Immunotherapy for patients with cancer is associated with severe side effects, including the possible induction of autoantibodies. The latter was proven for antithyroid microsomal and antithyroglobulin antibodies. METHODS: This study was designed to evaluate antiphospholipid antibodies (APA) in 30 patients receiving three different forms of immunotherapy for disseminated melanoma using interleukin-2 (IL-2), alpha-interferon (alpha-interferon) or the combination of both. RESULTS: APA were detected in none of 18 patients treated with IL-2 alone, 2 of 4 (50%) treated with alpha-interferon alone, and 3 of 8 (37.5%) treated with the combination of both. In the last group, increased concentrations of APA were observed, while the patients were still receiving alpha-interferon alone. APA levels were not detected in any of 10 patients with melanoma who were not treated with alpha-interferon or IL-2. In patients with increased APA, five of five (100%) had a prolongation of the partial thromboplastin time and 4 or five (80%) had deep venous thrombosis, which in one patient was followed by pulmonary embolism. CONCLUSIONS: The high incidence of therapy-induced elevated APA concentrations suggests that these should be carefully monitored in all patients receiving immunotherapy with alpha-interferon.