Tumor-specific immunity in sarcoma patients.

Stimulatory responses of 40 patients with bone [33] and soft tissue [7] sarcomas to autologous tumor cells were correlated with clinical data and prognosis. Although conclusive judgments for individual patients cannot be made, some genral features emerge: patients with stimulation indices greater than 1.5 have a 50 percent relapse-free interval after surgery of 22 months, patients with indices, below 1.5 have a 50 percent relapse-free interval of 5 months. 7 out of 10 responder patients are tumor-free 1 year after surgery as compared to 5 out of 19 (26 percent of non-responder pateints (p less than 0.05). Removal of the tumor is followed by an increase in the stimulatory response and by the dissappearance of blocking serum factors in patients with favourable prognosis. Responses return to baseline levels in tumor free patients 9-12 months after surgery. The results suggest that tumor-associated immune responses play a role in the development of human sarcomas. In addition, 47 lymphocyte samples of 25 patients were tested for stimulation by autologous tumor cells and for cell-mediated cytotoxicity against allogeneic sarcoma cell lines. Similar results were obtained in both test systems when pre-therapy lymphocytes were used. Discordant results were frequently seen at times after surgery. Both test systems may complement each other and may help clarify the tumor-specificity of certain lymphocytotoxic activities.