With the progress of genome research, precision medicine, which aims to select the optimal treatment based on genomic data from individual patients, is now attracting increasing attention in the field of cancer treatment. In the USA, a multiplex gene panel test using next-generation sequencing is now rapidly expanding in daily clinical practice. Our hospital has introduced a multiplex gene panel test （OncoPrime™）, which meets the Clinical Laboratory Improvement Amendment （CLIA） quality, for the first time in Japan since April 2015. Among 141 patients who received the OncoPrime™ test, some patients received clinical benefit from the therapy selected based on genomic data. We are now proceeding to develop a database system which integrates both genomic and clinical data of patients who receive a multiplex gene panel test in collaboration with six university hospitals. In the near future, precision medicine will play a pivotal role in the field of cancer treatment.