Assessment of in vivo effectiveness of tumoricidal chemotherapy and radiation therapy by serial analysis of tumor-associated urinary antigen titers in patients with sarcoma.

Serial measurements of tumor-associated antigens in the urine of patients with sarcoma who received preoperative intra-arterial doxorubicin and radiation therapy were assayed by microcomplement fixation. Changes in urinary antigen titer as a result of therapy were compared to pretreatment samples and were correlated with clinicopathologic evidence of in situ tumor cell destruction. Of the 53 patients with sarcoma studied, 44 had clinicopathologic evidence of tumor destruction induced by the preoperative therapy, and all 44 had a fourfold or greater rise in the level of urinary antigens during the treatment period. The other nine patients had no evidence of tumor destruction and antigen titers remained unchanged. Results suggested that tumoricidal therapy released tumor-associated antigens which could be detected in urine by microcomplement fixation. This phenomenon may be useful for measuring the in vivo effectiveness of tumoricidal therapy on nonaccessible tumors.