Lack of association of rheumatoid factor with either circulating immune complexes or tumor burden in cancer patients

The frequency of rheumatoid factor (RF) seropositivity and the frequency of association of RF with immune complex (IC) elevation were determined in 72 patients with a variety of solid tumors, in 78 patients with IC-associated diseases, 27 patients with non-IC-associated diseases, and in 31 normal healthy controls. The frequency of RF positivity in cancer patients (31%) was virtually identical to that in patients with IC-associated diseases (28%), and did not differ significantly from that seen in patients with non-IC-associated disease (15%). Whereas IC elevation was clearly related to tumor progress, RF was not. RF and IC status also appeared to be unrelated to each other, not only in cancer patients, but in patients with other diseases as well. The results do not support the concept that RF reflects progressive tumor growth or an immune response to IgG-containing immune complexes.