Novel biomedical imaging approach for detection of sentinel nodes in an experimental model of gastric cancer

Abstract

The aim of this study was to validate a novel imaging system that uses ATX-S10Na(II) to detect sentinel nodes (SNs) in gastric cancer. The new technique was compared with the enhanced visualization method using indocyanine green (ICG). Human gastric carcinoma cells were implanted orthotopically into 50 nude rats, which were divided into two groups. In the first group (n = 25), ATX-S10Na(II) was injected subserosally into the implanted site and visualized by a fluorescence spectrolaparoscope. In the second group (n = 25), ICG was similarly injected and observed through a near-infrared laparoscope. The presence of metastatic tumour cells was determined by reverse transcriptase-polymerase chain reaction specific for human beta-actin. ATX-S10Na(II) was clearly identified as a bright red colour, and was rapidly incorporated into the lymphatic system. Detection rates of SNs were 100 (95 per cent confidence interval (c.i.) 52 to 100) per cent (25 of 25) for ATX-S10Na(II) and 95 (95 per cent c.i. 40 to 100) per cent (21 of 22) for ICG. Sensitivity was 96 (95 per cent c.i. 45 to 100) and 81 (95 per cent c.i. 58 to 95) per cent respectively. These results support the validity of the ATX-S10Na(II)-guided approach in the detection of SNs in gastric cancer in vivo.