ENHANCEMENT OF ANTI-DNA TOPOISOMERASE-I AUTOANTIBODY RESPONSE AFTER LUNG-CANCER IN PATIENTS WITH SYSTEMIC-SCLEROSIS - A REPORT OF 2 CASES

Anti-DNA topoisomerase I (anti-topo I) antibody profiles were compared before and after lung cancer in 2 patients with systemic sclerosis (S Sc). Both patients developed adenocarcinoma of the lung late in the co urse of SSc and died of tbe cancer. Anti-topo I antibody levels, deter mined by doable immunodiffusion and enzyme-linked immunosorbent assay, increased markedly at the time of diagnosis of lung cancer. Furthermo re, patients' sera obtained after lung cancer reacted with multiple ep itopes on the entire topo I molecule, some of which had not previously been recognized. These results further support the concept that anti- topo I antibody production in SSc patients is due to an antigen-driven process.