Solely CD49f expression on pan-cytokeratin+ CD45− CTCs stratified patients with and without recurrent cancer (Supplementary S3D, E); however, a better discrimination was found when we considered concurrent CD49f and CD133 expression on CTCs (Fig. 4C, D) in comparison to solely CD49f expression on pan-cytokeratin+ CD45− CTCs underlining the relevance of CD49f and CD133. The gene discussed is ITGA6; the disease is cancer.