Individual and collective dissemination of tumor cells. Neoplastic cells can enter the circulation via either a hematogenous or lymphogenous route. Tumor cells tend to cluster together or may aggregate with immune cells to survive in the circulation. While the sentinel LNs often present a wide interlesion tumor cell heterogeneity, the clonal composition of metastases at the distant organ site displays substantially lower complexity. The figure was generated with BioRender.com.