[Evaluation of intratumoral bleomycin application in a tumor model and in a clinical pilot study].

In a total of 21 patients with squamous cell carcinomas of the oral mucosa 26.9% of the total volume of 57Co-Bleomycin injected into the tumor was found in the blood as early as 10 min following injection. Examinations using a gamma camera demonstrated that 94.6% of the substance have cleared the tumor tissue after just 1 h. This sharp and rapid drop in activity, which was particularly pronounced in carcinomas of the tongue and the floor of the mouth, might be caused by rapid resorption due to the high degree of vascularization of the maxillofacial region. Autoradiography showed deposits of the substance in tumor-free areas of the operation specimens. It seems that the postulated advantages of intratumoral application--increased concentration and depot effect in the tumor tissue--are no longer tenable, thus large-scale clinical trials with intratumoral bleomycin treatment cannot be justified.