Fig. 2

Pathological examination and immunohistochemical staining of the tumor. A The resected tumor is ulcerative, 10 cm × 8 cm × 5 cm in size, and has infiltrated into the serosa layer. B Histopathology shows that the tumor is high-graded UPS in the colon with fibrous hyperplasia, necrotic tissues, and inflammatory cells. C Immunohistochemical examination shows that tumor cells are positive for α1-antichymotrypsin. D Immunohistochemical examination shows that tumor cells exhibit marked positivity for vimentin. Scale bars = 200 µm