Cryopreservation for delayed circulating tumor cell isolation is a valid strategy for prognostic association of circulating tumor cells in gastroesophageal cancer

Figure 1 Representative images of circulating tumor cell isolation from fresh and cryopreserved samples demonstrating preservation of leukocyte and circulating tumor cell morphology. The fresh sample demonstrates a nucleated CK+/CD45- CTC which is uPAR negative, as well as a CK-/CD45+ leukocyte. The cryopreserved sample shows a uPAR positive CTC. CTC: Circulating tumor cell.