TBX1 and neoplasm: Metastatic cancer cells and CAFs form clusters in the circulation and these mosaic cell clusters co‐metastasize to distal tissues and organs.[28, 43, 59] On the basis of these findings, it has been suggested that metastatic cancer cells as seeds carry their own fibrotic soil with them.[59] Although the function of the circulating CAFs (cCAFs) in promoting cancer cell extravasation has not been investigated, it is reasonable to speculate that cCAFs contribute to extravasation of circulating tumor cells.