Isolated tumour cells in blood and E-cadherin expression in oesophageal squamous cell cancer

Abstract

Patients with oesophageal squamous cell carcinoma have a high rate of recurrence, even after curative resection. The aim of this study was to examine the correlation between the presence of isolated tumour cells (ITCs) in the blood and recurrence, and between the presence of ITCs and E-cadherin expression in the primary tumour in these patients. Blood samples obtained immediately before and after resection in 125 patients with oesophageal squamous cell carcinoma were examined by real-time reverse transcription-polymerase chain reaction using carcinoembryonic antigen mRNA. Blood samples from 28 healthy volunteers and 42 patients with benign diseases were used as controls. Seventy-seven patients (61.6 per cent) were ITC positive. ITC positivity correlated significantly with tumour depth, lymph node metastasis, stage, lymphatic invasion and venous invasion. Multivariable analysis revealed that tumour depth and ITC positivity were independent factors for a shortened haematogenous disease-free interval. A significant correlation was found between ITC positivity and reduced E-cadherin expression in the primary tumour (P < 0.001). ITC-positive patients with preserved E-cadherin expression had a longer disease-free interval (P = 0.016), haematogenous disease-free interval (P = 0.020) and overall survival (P = 0.004) than those with reduced E-cadherin expression. Examination of ITCs in the blood is useful for predicting haematogenous recurrence in patients with oesophageal squamous cell carcinoma.