A new review argues that tumor-derived extracellular vesicles (EVs) could be engineered into imaging tools to visualize the premetastatic niche before secondary tumors become detectable. The authors describe approaches spanning optical imaging as well as PET/SPECT and MRI/CT modalities. The work remains largely preclinical, but the review frames tumor EVs—already implicated in creating metastatic “preparation” environments—as candidate biomarkers that could support earlier intervention windows. For imaging and diagnostics developers, the thesis points to a path where EV characterization feeds imaging-target design, potentially improving the timing of metastasis detection relative to current imaging standards.