Circulating tumor cells (CTC) have been identified in peripheral blood from cancer patients especially those with metastatic lesions. Recently, the analysis of CTC has been developed rapidly and showed good prospects for individualized chemotherapy. The field of CTC research is very important since gene-expression profiling becomes feasible and real time when using CTC as the sample of evaluation. This review was to summarize present CTC detection, enrichment, or both methods and their contribution to individualized chemotherapy.