We have shown that the RT-qPCR-based multi-marker analysis using the six genes: CCNE2, DKFZp762E1312, EMP2, MAL2, PPIC, or SLC6A8 more than doubled the number of positive patients with recurrent breast cancer compared to the analysis of hMAM or EpCAM gene expression alone. The gene discussed is SLC6A8; the disease is breast cancer.