2143 - Benefit Analysis of Postoperative Adjuvant Therapy in Esophageal Squamous Cell Carcinoma Patients with Non-pCR or Non-MPR

Purpose/Objective(s):

To evaluate the survival benefits of postoperative pharmacotherapy and radiotherapy in esophageal squamous cell carcinoma (ESCC) patients with non-pathological complete response (non-pCR) or non-major pathological response (non-MPR), and to explore the optimal regimen.

Materials/Methods:

A retrospective analysis was conducted on 625 patients with ESCC who underwent neoadjuvant therapy followed by surgical resection at the Fourth Hospital of Hebei Medical University between January 2016 and December 2022, among whom 503 patients received postoperative adjuvant therapy. Inverse probability of treatment weighting (IPTW) was used to reduce confounding bias. Subgroup analysis was performed to identify populations that could benefit from adjuvant therapy. The Kaplan–Meier method and Log-rank test were used to compare the prognosis of patients among five perioperative treatment combinations.

Results:

1. Among all 625 patients, before IPTW, the 4-year disease-free survival (DFS) rate (62.7% vs 51.3%, P = 0.002) and 4-year overall survival (OS) rate (70.9% vs 51.6%, P < 0.001) were significantly higher in the adjuvant therapy group than in the non-adjuvant therapy group. After IPTW, the between-group differences remained statistically significant for 4-year DFS (62.4% vs 51.6%, P = 0.049) and 4-year OS (70.5% vs 52.0%, P < 0.001).
2. Among 575 patients with non-pCR, before IPTW, significant differences were observed between the adjuvant and non-adjuvant therapy groups in 4-year DFS (60.2% vs 46.8%, P = 0.001) and 4-year OS (68.9% vs 47.2%, P < 0.001). After IPTW, the differences remained significant for 4-year DFS (59.9% vs 48.0%, P = 0.041) and 4-year OS (68.5% vs 48.3%, P < 0.001).
3. Among 422 patients with non-MPR, before IPTW, the adjuvant therapy group had significantly higher 4-year DFS (54.4% vs 33.1%, P < 0.001) and 4-year OS (63.5% vs 33.2%, P < 0.001) than the non-adjuvant therapy group. After IPTW, the between-group differences remained statistically significant for 4-year DFS (53.7% vs 33.0%, P = 0.002) and 4-year OS (62.6% vs 33.0%, P < 0.001).
4. Comparison of the five perioperative treatment combinations showed that, both before and after IPTW, the neoadjuvant chemoimmunotherapy (NCIT) plus adjuvant chemoimmunotherapy (ACIT) group achieved the highest 4-year OS rates (89.8%, 91.2%; both P < 0.001), followed by neoadjuvant chemotherapy plus adjuvant chemotherapy (74.2%, 72.2%), neoadjuvant chemoradiotherapy plus adjuvant chemotherapy (64.4%, 66.9%), neoadjuvant chemotherapy plus adjuvant chemoimmunotherapy (46.3%, 49.7%), and neoadjuvant chemotherapy plus adjuvant chemoradiotherapy (32.7%, 30.0%).

Conclusion:

Postoperative adjuvant therapy significantly improves survival in patients with non-pCR and non-MPR. Neoadjuvant chemoimmunotherapy combined with adjuvant chemoimmunotherapy may represent the most effective perioperative treatment strategy.