This book highlights the importance of diagnostic techniques using volumetric measurements for screening, evaluation of tumors and identification of metastases. Cancer is a pathologic biological process. Various Therapies and drugs are designed to interfere with the pathologic process and should therefore also be validated using a functional screening method directed. Screening of the cancers at right time and also evaluating them is very important. Volumetric measurement helps in better screening and evaluation of the tumors. Volumetry is a process of assessment of the tumors by identification and evaluating the tumor by measuring the size. Volumetric image analysis is an accurate, precise and medically valuable bio-marker of response in the assessment of tumors. It also helps in identifying the possible outcomes such disease progression (PD) or complete response where the complete disappearance of the tumor. Also, could possibly aid in identification of metastases.