Lymphocyte blastogenesis induced by autochthonous human solid tumor cells: Relationship to stage of disease and serum factors

Tumor‐induced blastogenesis was detected in vitro in autologous lymphocytes from 19 of 29 patients with solid tumors. The blastogenic response was dose related, and maximum response required a tumor cell‐lymphocyte ratio of 1:1. The intensity of response correlated inversely with the extent of disease. Tumor cells from patients with widespread disease seem to have a lower stimulatory capacity regardless of their site of origin (primary or metastatic lesion). The effect of serum from cancer patients on the blastogenic response was mostly nonspecific, and could be both inhibitory or facilitory. It did not correlate with the extent of disease.