Complete local tumor remission after therapy with extra-corporeally applied high-energy shock waves (HESW).

High-energy shock waves (HESW) have recently been proposed as a means of non-invasive tumor therapy. Here we report the first successful local treatment of experimental tumors by means of multifocal and reported application of HESW. The experiments were performed on 29 Syrian golden hamsters bearing amelanotic hamster melanomas in the dorsal skin. HESW, generated electrohydraulically, were applied multifocally to the center and to 5 sites on the margin of the tumors. A group of animals undergoing surgical resection and an untreated group served as controls. Complete remission of local tumor was achieved in more than 90% of the HESW-treated hamsters and in the same number of surgically treated animals, while untreated tumors continued to grow. Frequency of metastasis was the same in both groups after HESW treatment or surgery. Tumor therapy with multifocally and repeatedly applied HESW was thus as successful as surgery.