The genome represents a design for creating the body, with each one being different. In cancer genomic medicine, many genes are simultaneously examined using mainly cancer tissues (the oncogene panel test), and gene mutations are revealed. Cancer treatments are then initiated according to each individual's constitution and medical condition based on gene mutations. A system for cancer genome medical treatment is currently being developed. In the treatment of several cancer types, the "oncogene test with an oncogene companion diagnosis" is already being performed as a standard test using cancer tissue to detect one or several gene mutations. On June 1, 2019, the cancer gene panel test was covered by the national health insurance system in Japan, and a system to initiate cancer genome medical treatment has begun. The prospects and problems associated with cancer genome medicine are discussed herein.