To provide methods for developing a successful non-toxic therapy by identifying the basis of cancer specificity and then applying the specificity.SOLUTION : The present invention describes a method for identifying a tumor specific epitope from a cancer tissue DNA of a cancer patient using both DNA sequencing and bioinformatics techniques. Identification of tumor specific epitopes provides a pharmaceutical composition having a limited number of tumor specific peptides suitable for personalized genomics-based immunotherapy of human cancer. Particularly, a novel index called the Differential Agretopic Index (DAI) with respect to epitopes is disclosed. This enables prediction whether an immunity by a particular epitope is protective against tumors. A pharmaceutical composition and an administration method are also included.SELECTED DRAWING : None