Treatment Strategies for Oligo-Recurrence After Radical Esophagectomy for Esophageal Cancer According to Site of Recurrence

Background The recurrence rates in patients with esophageal cancer who are treated by curative esophagectomy is very poor. On the other hand, some patients with recurrence after esophagectomy have achieved long-term survival with multidisciplinary treatment. Recently, the concept of oligo-recurrence has gained attention. We investigated the characteristics and prognosis of patients with oligo-recurrence after esophagectomy. Methods We included 135 patients with recurrence among 490 patients who underwent esophagectomy for esophageal cancer between January 2010 and March 2021 at our hospital. Oligo-recurrence was defined as five or fewer recurrences in a single organ or five or fewer recurrences in a single lymph node. Patients were divided into two groups: the oligo-recurrence group and the non oligo-recurrence group. We evaluated the prognosis of patients with oligo-recurrence, focusing especially on its correlation with the site of recurrence, treatment after recurrence. Results Of the 135 recurrence patients, 46 (34%) were in the oligo-recurrence group and 89 (66%) were in the non oligo-recurrence group. The overall survival was 38 months in the oligo-recurrence group and 18 months in the non oligo-recurrence group (p < 0.001). Survival after recurrence was 23 months in the oligo-recurrence group and 7 months in the non oligo-recurrence group (p < 0.001). The prognosis was better in the lymph node recurrence group than in the liver recurrence group (p = 0.04). 25 lymph node recurrence patients (86%) received chemoradiotherapy, all liver recurrence patients received chemotherapy, and 4 lung recurrence patients (80%) patients underwent lung resection. Conclusion Oligo-recurrence after radical esophagectomy for esophageal cancer may be associated with a favorable prognosis. Radical treatment may be useful in lymph node and lung oligo-recurrence.