Preoperative chemotherapy compared with postoperative adjuvant chemotherapy for squamous cell carcinoma of the thoracic oesophagus with the detection of circulating tumour cells randomized controlled trial

Background: The role of preoperative chemotherapy in the treatment of patients with oesophageal squamous cell carcinoma (ESCC) remains controversial. Chemotherapy followed by surgery was compared with surgery +/- chemotherapy, and the detection of circulating tumour cells (CTCs) was performed on all enrolled patients. Methods: We randomly assigned patients with resectable tumours to the preoperative chemotherapy group (Pre group) or surgery group (patients who were either given or not given adjuvant chemotherapy according to their postoperative lymph node status, Post group). Blood samples were collected 1-3 days before treatment (including preoperative chemotherapy and surgery) and 7 days after surgery for CTC detection. Results: From July 2016 to October 2018, 115 patients were enrolled in the study, of whom 57 were assigned to the Pre group and 58 to the Post group. The proportion of patients with stage III ESCC was 63.16% in the Pre group and 48.28% in the Post group. No patients died during chemotherapy. One patient exhibited a complete response to preoperative chemotherapy, and 13 patients exhibited partial responses. The 2-year progression-free survival (PFS) and overall survival (OS) rates were not significantly different between the Pre and Post groups. In the subgroup analysis, patients with CTC (+) prior to treatments receiving preoperative chemotherapy had a better 2-year PFS (71.90% vs. 38.73%, P = 0.0379). In the Cox proportional hazards regression analysis, platelet count was proven to correlate significantly with disease progression (P = 0.016), and no factors were proven to correlate significantly with mortality after the factors were balanced in the present analysis. Conclusions: Preoperative chemotherapy improved the short-term PFS when CTC detection was positive prior to any treatment for patients with stage II or III ESCC. CTC detection may be used as an index to guide individualized strategic decisions regarding preoperative chemotherapy, but more evidence is needed.