Analysis of mast cells isolated from 15 pairs of fresh intestinal tumour tissues and adjacent normal tissues, as well as 7 HC tissues. (A) The frequency of tissue-infiltrating mast cells was analysed by flow cytometry. The percentage indicates the frequency of mast cells in the CD45+ cell population. (B) The frequency of mast cells in tumour tissues, adjacent normal tissue and HC tissues. (C) The frequency of mast cells in tumour and adjacent normal tissues from patients with early- and advanced-stage CRC. (D) The frequency of mast cells in tumour and adjacent normal tissues does not correlate with TNM stage or T stage in patients with CRC, as determined by Spearman's correlation coefficient analysis. CRC, colorectal cancer; n.s, no significance; SSC, side scatter; TNM, Tumour-Node-Metastasis.