Fig. 3

Histopathological findings showed that the peritumoral area is highly fibrotic, which suggested that the tumor had shrunk by FOLFIRINOX. White arrows indicate remaining tumor cells surrounded by fibrosis (A) (HE × 20). The tumor cells were pleomorphic, irregularly shaped to spindle-shaped, and surrounded by osteoclast-like multinucleated giant cells, consistent with the diagnosis of UCOGC (B), (HE × 400). Both the cytoplasm of the cancer cells and osteoclast-like giant cells are positive for PD-L1 immunostaining (C) (PD-L1 immunostaining × 400)