The patterns and risk factors for relapse in oesophageal squamous cell cancers that achieve pathological complete response to neoadjuvant chemoradiotherapy.

Abstract

The goal of this study was to investigate the patterns and risk factors for recurrence in patients with oesophageal squamous cell carcinoma with a pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT). Between January 2008 and December 2018, a total of 96 patients with pCR were enrolled in this study. Lymph nodes with a pCR [LN-ypCR response (+)] were defined as those lymph nodes without residual tumour but with the presence of treatment response to nCRT. Prognostic factors for recurrence-free survival (RFS) were analysed with Cox proportional hazards models and Fine-Gray competing risk models. Lymph node (LN) stations were counted according to the Japan Esophageal Society classification. The median follow-up time was 51.5 months. Recurrence occurred in 15 cases (15.6%) with a 9.9-month median time to recurrence and a 15.6-month median survival after recurrence. The majority of recurrent diseases developed within the first 2 years postoperatively. Distant recurrences were detected in 14 cases (14.6%), in which the most common recurrence sites were no.104 LN and the lung, followed by no.16 LN. The mean RFS in the whole cohort was 116.6 months. The LN-ypCR response (+) was identified as the independent prognostic factor for worse RFS in both the multivariate Cox model and the Fine-Gray competing risk model (P = 0.001 and P = 0.002, respectively). Relapse is not rare in oesophageal squamous cell carcinoma cases with pCR after nCRT. Distant recurrences, the predominant pattern of relapse, occur primarily within the first 2 years after oesophagectomy. Patients with pCR with an LN-ypCR response (+) have a higher risk for postoperative recurrence.