etoposide + cisplatin + epirubicin + cyclophosphamide + PD-1

This is a combination regimen consisting of four cytotoxic chemotherapy agents—etoposide, cisplatin, epirubicin, and cyclophosphamide—together with a programmed cell death protein 1 (PD-1) inhibitor (checkpoint inhibitor). Etoposide is a topoisomerase II inhibitor that induces DNA strand breaks in rapidly dividing cells. Cisplatin is a platinum-based agent that forms DNA crosslinks and inhibits DNA synthesis. Epirubicin is an anthracycline antibiotic that intercalates into DNA and inhibits topoisomerase II. Cyclophosphamide is an alkylating agent causing crosslinking of DNA strands. The addition of PD-1 inhibitors (such as pembrolizumab or nivolumab) blocks the PD-1 immune checkpoint pathway on T cells, enhancing antitumor immune responses by preventing tumor-induced T-cell inhibition[6][8][10]. This combination aims to maximize direct cytotoxic effects on cancer cells while also stimulating the immune system to attack tumors.