(A) Micrographs showing cell surface vimentin staining in the fresh and cryopreserved samples with different time lapse before cryopreserving PBMCs: less than 2 h, 24h and 48h. Graph shows the results of CTCs counts among fresh sarcoma samples (B) and cryopreserved ones (C) with different time lapse before isolating PBMCs: less than 2h, 24h and 48h. CSV (84-1, green), nuclear stain (blue). GIST, Gastrointestinal stromal tumor. Scale indicates 10 μm. The group of time-lapse less than 2 hours was used as the reference.* P<0.05