Clinical Outcomes of First-Line Immune Checkpoint Inhibitor-Based Therapy for Postoperative Recurrence After Adjuvant...

Adjuvant nivolumab has become a standard treatment after curative resection for locally advanced esophageal cancer; however, postoperative recurrence remains common. The efficacy of immune checkpoint inhibitor (ICI)-based therapy for postoperative recurrence in patients treated with adjuvant nivolumab remains unclear. This study evaluated the clinical outcomes of first-line ICI-based therapy for postoperative recurrence, focusing on the impact of prior adjuvant nivolumab exposure.

This single-center retrospective study included 81 patients who developed postoperative recurrence after radical esophagectomy and subsequently received first-line ICI-based therapy. Propensity score matching (PSM) was performed to adjust for baseline differences. Treatment outcomes were assessed based on treatment response, progression-free survival, and overall survival (OS) after recurrence.

Among the 81 patients, 27 had received adjuvant nivolumab and 54 had not. Treatment responses, including the proportion of patients achieving early tumor shrinkage ≥ 20%, were similar between patients with and without prior adjuvant nivolumab exposure. After PSM, no statistically significant differences were observed in treatment response. No significant differences were observed in progression-free survival (hazard ratio 1.4, 95% confidence interval 0.74-2.64, p = 0.298) or OS (hazard ratio 1.23, 95% confidence interval 0.61-2.50, p = 0.56). Two-year OS was 44% and 42.9% in the adjuvant and non-nivolumab groups, respectively.

First-line ICI-based therapy for postoperative recurrence demonstrated no statistically significant differences in clinical outcomes irrespective of prior exposure to adjuvant nivolumab, suggesting that previous adjuvant immunotherapy does not preclude clinical benefit from subsequent ICI-based therapy at recurrence.