[Destruction of ureteral tumors with the neodymium-YAG laser. A new, organ-preserving surgical procedure].

Only the neodymium-YAG laser is suitable for destroying tumors endoscopically, because it shows a very high transmission through water and a slight absorption in the tissue. It means scattering becomes important and leads to a homogeneous and uniform distribution of the radiation in the tissue producing a deep thermal effect. An examination of a section through a bladder wall under light microscope after neodymium-YAG laser irradiation shows a layered, sharply delimited coagulation necrosis that extends to all of the bladder wall layers and reaches the outermost zones. In this way it is possible to destroy not only the exophytic part of a tumor but also the tumor base in the tissue. Since 1976 we destroyed more than 4000 bladder tumors by laser application. For tumors on the ureter or kidney pelvis a special endoscope, described by Perez-Castro Ellendt and modified by us, can be used, if it is not possible to perform a conventional operation. It is reported about four cases of distal ureter tumors (GI-II) in patients who had refused an operation for removing the tumor bearing ureter segments. Now, for more than one and half a year all patients are free of tumors and the irradiated ureters show a good function. This novel procedure is not for routine, but for high risk patients or patients, who refuse an open operation.