Importance of long-term surveillance after curative esophagectomy for esophageal squamous cell carcinoma

Background The long-term outcomes after esophagectomy for esophageal cancer remain uncertain and the optimal surveillance strategy after curative surgery remains controversial. Methods In this study, the clinicopathological characteristics of patients who underwent curative thoracic esophagectomy between 1991 and 2015 at Toranomon Hospital were retrospectively analyzed and reviewed until December 2020. We evaluated the accumulated data regarding the pattern and rates of recurrence and second malignancy. Results A total of 1054 patients were eligible for inclusion in the study. Of these, 97% were followed up for 5 years, and the outcomes after 25 years could be determined in 65.5%. Recurrence was diagnosed in 318 patients (30.2%), and the most common pattern was lymph node metastasis (n = 168, 52.8%). Recurrence was diagnosed within 1 year in 174 patients (54.7%) and within 3 years in 289 (90.9%). Second malignancy possibly occurred through the entire study period after esophagectomy even in early-stage cancer, keeping 2%-5% of the incidental risk. There was no significant difference in the prognosis between 3-year survivors with and without a second malignancy. Conclusions Most recurrences after resection of esophageal cancer occurred within 3 years regardless of disease stage. However, these patients have an ongoing risk of developing a second malignancy after esophagectomy. Further consideration is required regarding the efficacy of long-term surveillance.