The potentiation of radiation effects with 5-fluoro-uracil.

A preliminary study of the response of various inoperable malignant diseases to simultaneously administered 5-fluoro-uracil and orthovolt x-ray was performed. The 5-fluoro-uracil was given intravenously at a relatively nontoxic dosage level. The x-ray tumor dose was limited to 2,000 roentgens in every patient. Pronounced and rapid tumor regression occurred in 12 of 18 evaluable patients. Significant objective response was obtained in each of eight patients with epidermoid carcinoma of the lung. Toxicity occurred in half of the patients, manifested by pharyngitis, esophagitis, proctitis, leukopenia and thrombocytopenia.