2978 - A Phase II Clinical Trial of Radiotherapy Combined with Anlotinib in Locoregional Recurrent Esophageal Squamous Cell Carcinoma after Radical Surgery

C. Fan¹, F. Liu¹, C. He¹, J. Liu¹, Y. Jiang¹, J. Zhang¹, X. Wu¹, Y. Sun¹, X. Zheng¹, and H. Ge²; ¹Department of Radiation Oncology, The Affiliated Cancer Hospital of Zhengzhou University & Henan Cancer Hospital, Zhengzhou, Henan, China, ²Department of Radiation Oncology, Henan Cancer Hospital, Zhengzhou, Henan, China

Purpose/Objective(s): Anlotinib has shown antitumor activity in third or further-line treatment for advanced esophageal carcinoma. This trial aimed to evaluate the efficacy and safety of radiotherapy combined with anlotinib in the treatment of locoregional recurrent esophageal squamous cell carcinoma (ESCC) after radical resection. Materials/

Methods: Patients met the criteria for enrollment received radiotherapy (50.4-59.4 Gy) combined with anlotinib (12 mg, d1-14). Anlotinib was administered concurrently with radiotherapy for 2 cycles, and sequentially with another 2 cycles. The primary endpoints were objective response rate (ORR) and toxicity. The secondary endpoints were local failure-free survival (LFFS), distant metastasis-free survival (DMFS), progression-free survival (PFS) and overall survival (OS).
Results: Between October 2019 and July 2022, 40 patients were enrolled. The median follow-up time was 22.2 months (range, 9.3-34.6 months). The ORR was 90% (20% complete remission, 70% partial remission). The median LFFS, DMFS, PFS and OS were 19.8 months (95% confidence interval [CI], 9.693-29.907), 26.4 months (95% CI, 21.054-31.746), 12.3 months (95% CI, 4.928-19.672) and 28.0 months (95% CI, 20.966-35.034), respectively. Patients receiving 59.4 Gy had significantly longer LFFS (HR = 0.253, 95% CI, 0.104-0.620, P = 0.003) and OS (HR = 0.319, 95% CI, 0.104-0.973, P = 0.045) than patients who received a reduced irradiation dose of 50.4-56 Gy. No grade 4 treatment related adverse events occurred. Grade 3 adverse events occurred only in 2 patients (5%) who developed hypertension.
Conclusion: Radiotherapy and anlotinib achieved a promising ORR and relatively lower toxicity compared to previously reported data in ESCC patients with locoregional recurrence after surgery. Further randomized controlled trials with larger sample size are warranted in the treatment of such patients.