Prognostic Significance of Serum Tumor Markers According to the Timing of Recurrence After Curative Esophagectomy for Esophageal Squamous Cell Carcinoma

Background Reliable biomarkers for predicting post‐recurrence survival in esophageal squamous cell carcinoma (ESCC) remain limited. We evaluated the prognostic significance of three serum tumor markers routinely used in clinical practice (carcinoembryonic antigen [CEA], squamous cell carcinoma antigen [SCC], and serum p53 antibody [p53‐Ab]) in patients with recurrent ESCC after curative esophagectomy. Methods Sixty patients who developed recurrence after curative resection for ESCC were retrospectively analyzed. Overall survival (OS) after recurrence was compared according to serum CEA, SCC, and p53‐Ab levels measured at recurrence. Exploratory subgroup analyses were performed according to the timing of recurrence. Results Elevated SCC levels at recurrence were significantly associated with worse post‐recurrence OS ( p < 0.01), whereas CEA and p53‐Ab levels were not. Multivariable analysis identified elevated SCC as an independent predictor of poor post‐recurrence survival (hazard ratio, 2.50; 95% confidence interval, 1.18–5.33; p = 0.02). In the exploratory analysis according to recurrence timing, elevated SCC levels were associated with worse survival among patients with standard recurrence ( p < 0.01), whereas no significant associations were observed for CEA or p53‐Ab. Among patients with late recurrence, elevated p53‐Ab levels showed a possible association with poorer survival ( p = 0.05). Conclusions Serum SCC measured at recurrence may serve as a prognostic biomarker for post‐recurrence survival in patients with ESCC after curative esophagectomy. Exploratory analyses according to recurrence timing suggested that SCC may be particularly relevant in standard recurrence, whereas p53‐Ab showed a possible prognostic association in late recurrence.