Mathematical analysis of CA125 kinetics during first line chemotherapy allows calculation of various biologic parameters which are powerful indicators of the therapeutic efficiency. The purpose of this study is to present an original method of interpretation of CA125 kinetics based on both CA125 profile and its half-life value. The first part of this study reviews the practical modalities of CA125 kinetics analysis, the methods of calculation of the biologic parameters as well as the guidelines of interpretation. The second part of this work is dedicated to the presentation of CA125 profile characteristics in responders to chemotherapy, partially or totally nonresponders to chemotherapy, tumoral growth under treatment and tumor lysis syndrome.