[Rheumatoid factor in oncological patients]

In sera of 20% of patients with tumors of different localization and histological type the rheumatoid factor (RF) was found, which more frequently occurs in patients with soft tissue tumors as compared with bone tumors. The blocking properties of the sera revealed by RBT to PHA and by RIML would show no correlation with the occurrence of RF in them. Water-salt extracts of some tumors contain RF, which occurrence correlates well with the concentration of tumor cells having receptors for Fc-site of IgG on their surface.