Luchini C, et al. - Using antibodies against PD-1, PD-L1 and CD163, 27 pancreatic undifferentiated carcinomas with osteoclast-like giant cells (UCOGCs), 5 extra-pancreatic tumors with osteoclast-like giant cells and 10 pancreatic anaplastic carcinomas (ACs) were immunostained to examine the expression of PD-1, PD-L1 and CD163 in a series of UCOGC. According to the findings obtained, PD-L1 expression on neoplastic cells of UCOGC showed a poor prognostic value. It was noted that patients with PD-L1-positive UCOGCs had a risk of all-cause mortality that was three times higher vs patients with PD-L1-negative UCOGCs. The outcomes might have important implications for immunotherapeutic strategies in UCOGCs, and these tumors might represent a model for future therapeutic methods against pancreatic ductal adenocarcinoma (PDAC).