Reflected ultrasound scanning (echography) is rapidly developing into a prime tool for tumor diagnosis, outlining, and detection. The principles of echographic diagnosis of neoplasms, the accepted uses in detection and diagnosis, as well as some of the principles of internal and contour patterns are discussed. Echography is very helpful in determining the size, location, organ origin, internal characteristics, and course of neoplasms in the abdominal area, neck, and extremities. Echography is helpful in radiation therapy planning and is expected to assume an increasing role in the diagnosis and management of tumors.