Efficacy and safety of the combination of anlotinib and envafolimab in the treatment of unresectable or metastatic liposarcoma: findings from a single-center retrospective study - Liu, Hongliang; Hao, Qisheng; Wang, Xi; Cheng, Mengxing; Qiu, Fabo; Zhou, Bin (Frontiers in Oncology, 2025)