We observed a significantly smaller tumour cell size (P = 0.007) (Fig. 4g and Supplemental Fig. 9A) and a significantly lower tumour cell circularity (P = 0.002) (Fig. 4h and Supplemental Fig. 9B) of Trop-2/CD-49f-based enriched CTCs. Here, TACSTD2 is linked to neoplasm.