Fig. 1.

Circulating tumor cells (CTCs) isolated from non-metastatic colon cancer. Photomicrographs of CD45-immunonegative CTCs (A and B) and circulating tumor microemboli (CTM) (C and D) isolated from patient blood samples. Leukocytes isolated from a healthy individual (E) and cells from a healthy blood spiked with HCT-8 cell line (F). Thin arrows identify isolated CTCs, thick arrows indicate leukocytes, and asterisks show locations of 8-µm pores in polycarbonate membranes. (G) Median CTC counts (8 mL samples) by pathological stage (pS) at baseline (C1) and follow-up (C2). (H) Disease-free survival (DFS) in relation to CTC counts at C1 (≤5 vs. >5 CTCs/8 mL; p = 0.3). (I) DFS in relation to CTC counts at C2 (≤5 vs. >5 CTCs/8 mL; p = 0.17).