Association between tumor volume changes during neoadjuvant chemoimmunotherapy and survival outcomes in esophageal squamous cell carcinoma: a multicenter study

Purpose: In recent years, neoadjuvant chemoimmunotherapy (NICT) has become a research focus in the treatment of esophageal cancer. This study aims to evaluate the predictive value of tumor volume changes before and after NICT for prognosis in patients with operable esophageal squamous cell carcinoma (ESCC). Materials and methods: This retrospective study included 163 patients with histologically confirmed ESCC from two medical centers between October 1, 2020, and October 1, 2022. All patients received NICT before undergoing radical esophagectomy. Based on pre- and post-treatment CT images, we delineated and calculated the volume of the esophageal tumor. The rate of tumor volume change was then analyzed for its association with patient prognosis. The study endpoints were overall survival (OS), disease-free survival (DFS) and progression-free survival (PFS). Results: Multivariate regression analysis indicated that tumor location, number of NICT cycles, and tumor volume change rate were independent influencing factors for both DFS and PFS. The interval between NICT completion and surgery, along with tumor volume change rate, were independent factors for OS. Significant tumor volume reduction served as a predictor of favorable prognosis, demonstrating certain predictive value for long-term survival in patients. Surgery performed within 6 weeks of neoadjuvant therapy was significantly associated with longer OS, while DFS and PFS also showed a trend toward improvement. Conclusion: The change in tumor volume before and after neoadjuvant therapy is an independent prognostic factor for esophageal cancer patients receiving NICT. Additionally, performing radical surgery as soon as possible after completing neoadjuvant therapy is associated with improved survival outcomes.