CD274 and undifferentiated pleomorphic sarcoma: Research suggests that while some patients with leiomyosarcoma (LMS) may benefit from immune checkpoint inhibitors (e.g., PD-1/PD-L1 inhibitors like nivolumab and pembrolizumab) (78), histological subtype analyses reveal that LMS has the lowest response rates compared to subtypes such as alveolar soft part sarcoma and undifferentiated pleomorphic sarcoma, which show the highest (78).