[Ultrasound in tumor diagnostics. Possibilities and problems with regard to internal medicine as an example (author's transl)].

Ultrasound B-scan (real time and gray scale technique) has proved to be a noninvasive, low expensive and suitable method in internal tumor diagnostics. The most important fields are the diagnosis of pancreatic tumors, of malignant lymphomas, of tumors of the kidneys and the adrenal gland. Furthermore there is possible the diagnosis of tumors of the liver, the bile ducts, the spleen and the thyroid gland. The differentiation between solid and cystic tumors has shown to be a domain of ultrasonography. The limitations of the method are caused by the relatively bad (lateral) resolution of ultrasonography. Therefore tumors smaller than 1.5 cm cannot be diagnosed regularly. There is, moreover, no ultrasonic pattern typical of malignancy.