Recent Progress in the Neoadjuvant Treatment Strategy for Locally Advanced Esophageal Cancer

Neoadjuvant therapies, primarily chemotherapy and chemoradiotherapy, are able to improve the overall survival (OS) in patients with locally advanced resectable esophageal cancer (EC) based on the results of several randomized clinical trials. The advantage of neoadjuvant therapy is chiefly attributed to the decreased risk of local-regional recurrence and distant metastasis. Thus, it has been recommended as standard treatment for patients with resectable EC. However, several fundamental problems remain. First, the combination of neoadjuvant chemotherapy (nCT), neoadjuvant chemoradiotherapy (nCRT), and surgery for EC patients with different histological types remain controversial. Furthermore, to reduce the toxicity of preoperative chemotherapy and the risk of complications caused by preoperative radiation therapy, the treatment protocols of nCT and nCRT still need to be investigated and optimized by prospective trials. Moreover, for patients with complete clinical response following neoadjuvant therapy, it is worth ascertaining whether a "watch and wait" surveillance plus surgery-as-needed policy is more favorable, as well as, in addition to preoperative chemoradiotherapy, whether immunotherapy, especially when combined with the traditional neoadjuvant therapy regimens, brings new prospects for EC treatment. In this review, we summarize the recent insights into the research progress and existing problems of neoadjuvant therapy for locally advanced resectable EC.