Systemic treatment of advanced esophageal squamous cell carcinoma: chemotherapy, molecular-targeting therapy and immunotherapy

Systemic treatment of advanced esophageal squamous cell carcinoma (ESCC) mainly consists of cytotoxic agents, aiming to palliate symptoms and prolong survival. Cisplatin and 5-fluorouracil have been considered standard treatment for several decades. Efforts to develop more effective treatment have led to clinical trials testing triplet, irinotecan-based, oxaliplatin-based and paclitaxel-based regimens. Molecular-targeting agents, mainly anti-EGFR inhibitors including gefitinib, panitumumab and nimotuzumab, have been investigated; however, no molecular-targeting agents demonstrate the clinical utility in Phase 3 trials so far. Negative results from Phase 3 trials testing gefitinib and panitumumab suggest the importance of identifying predictive biomarkers of responses to molecular-targeting agents. On the basis of results from Phase 3 trials testing PD-1 inhibitors, nivolumab and pembrolizumab, are anticipated to be the standard treatment for patients with ESCC. Dual immune checkpoint inhibition and immunotherapy in combination with cytotoxic agents are under study. Recent advances in next-generation sequencing technologies provide comprehensive catalogues of genetic alterations in ESCC which may lead to therapeutic breakthroughs in a personalized manner. Here, we review the existing clinical data and discuss future perspectives with a focus on the systemic treatment of advanced ESCC.