INTRA-ARTERIAL 5-BROMODEOXYURIDINE AND X-RAY THERAPY

Abstract

In the patients who received intra-arterial BUdR [bromodeoxyuridine], early reaction in both the neoplasm and the mucosa was consistent with the results of combined radiation and BUdR treatment reported by Fletcher. Contrary to their experience, we were able to demonstrate 4.9 percent thymidine replacement by BUdR in the DNA extracted from infused neoplastic tissue in 1 instance. Early tumor response was sometimes evident along with increased cutaneous reaction, in patients receiving intravenous IUdR [iododeoxyuridine] plus irradiation. Clinically, useful radiosensitization with a pyrimidine analogue appears to depend upon the achievement of preferential uptake of the BUdR into the DNA of the neoplastic cells, and incorporation of the analogue into all of the cells of the neoplasm. Reliance upon a supposed difference in mitotic activities between normal and neoplastic tissue for achieving a differential uptake appears inadequate. The relative rates of cellular proliferation between normal and neoplastic tissue are not clearly defined. Despite the clinical evidence for radiosensitization of neoplastic and normal tissues alike noted in this small series, a method for achievement of differential radiosensitiza-tion of carcinoma in man with the pyrimidine analogues remains elusive.