Figure 4 are representative images of the different types of cell staining observed, including: (1) a traditional CTC with γ-H2AX, nuclear, foci staining, (2) a traditional CTC with only peripheral γ-H2AX staining, (3) a CTC with γ-H2AX, nuclear, foci and peripheral staining, and (4) a cohesive cluster of cells suggestive of tumor embolus that exhibits traditional CTC characteristics and γ-H2AX, nuclear, foci staining. Here, H2AX is linked to neoplasm.