Patent ID: 7323304

Claim:
A method for detecting disseminated tumor cells that express any of cytokeratins 1-20 from a body fluid, in which non-tumor cells which express at least one of cytokeratins 1-20 are separated from tumor cells which express at least one of cytokeratin 1-20, the method comprising: a) enriching tumor cells by a cell separation medium which has a density in the range from 1.055 to 1.065 g/ml being overlaid with the body fluid and being centrifuged, thus separating cytokeratin-positive and cytokeratin-negative blood cells from one another, with the enriched tumor cells being present in the same fraction as the cytokeratin-negative blood cells; wherein the centrifugation is carried out in a vessel which is divided by a porous barrier, a filter, a sieve, or a flap into an upper and a lower compartment, the cell separation medium being introduced into the lower compartment, and the body fluid being put in the upper compartment, and wherein the porous barrier, the filter, the sieve or the flap has a thickness of 0.5-10 mm; and b) using RT-PCR with a cytokeratin 1-20 specific primer to detect said any cytokeratin 1-20 expressing tumor cells in said enriched tumor cell fraction.