Abstract: This invention provides a method of detecting cancer metastatic cells in a subject, comprising: a) obtaining a nucleic acid sample from the subject's blood; b) amplifying nucleic acid encoding the product of prostate carcinoma tumor antigen gene-1; and c) detecting the presence of nucleic acid encoding the product of the prostate carcinoma tumor antigen gene-1, thereby detecting cancer metastatic cells in a subject. This invention also provides the above-described methods, wherein the method of amplification is PCR. This invention further provides the above-described methods, wherein the primers are 5′-AAGCTGACGCCTCATTTGCA-3′ SEQ ID NO: 1 and 5′-AACCACCAATGGAACTGGGT-3′ SEQ ID NO: 2. This invention also provides the above-described methods, wherein the primers are 5′-AATGGCTTCTGTGATACT-3′ SEQ ID NO: 3 and 5′-GGCTATAAGTGTTGCTGC-3′SEQ ID NO: 4.