Postoperative Adjuvant Therapy Improves Survival in Pathologic Nonresponders After Neoadjuvant Chemoradiation for Esophageal Squamous Cell Carcinoma: A Propensity-Matched Analysis

Abstract

The prognosis of patients with esophageal cancer who have poor response to chemoradiotherapy (ie, pathologic nonresponders [pNRs]) remains poor. We investigated whether the use of postoperative adjuvant therapy (AT) could improve survival in this patient group. Among patients with esophageal squamous cell carcinoma who were treated with neoadjuvant chemoradiotherapy (nCRT) and operation between 2000 and 2012, pNRs (defined as those having a postoperative T stage of equal or greater pretreatment T stage or persistent nodal disease) were identified and divided into two groups according to their subsequent management (AT versus surveillance). Survival and recurrence were compared after propensity score matching for the following five factors: age, performance status, pathological lymph node status after treatment (ypN) status, severity of postoperative complications, and length of hospital stay (LOS). Of the 115 pNRs, 74 and 41 received AT and surveillance alone, respectively. Patients who received AT were younger, had less major postoperative complications, and a shorter LOS. A total of 32 pairs of well-balanced patients (n= 64) were selected by propensity matching. A significant benefit in terms of disease-free survival (DFS) was observed for pNRs treated with AT compared with those undergoing surveillance (3-year DFS rate: 45% versus 22.3%, p= 0.022). However, more patients in the AT group died of causes unrelated to cancer, resulting only in a borderline increase of overall survival (OS) [3-year OS rate: 34.4% versus 21.6%, p=0.13]. Postoperative AT can improve DFS in pNRs after nCRT. However, its use should be carefully weighed against a potential increase in the risk of treatment-related death.