Detection of sentinel nodes by a novel red-fluorescent dye, ATX-S10Na (II), in an orthotopic xenograft rat model of human gastric carcinoma

Abstract

Background and Objective: We developed a new imaging system to detect sentinel nodes (SNs) using a novel fluorescent tracer, ATX-S10Na(II), and investigated its usefulness in an animal model. Study Design/Materials and Methods: Human gastric carcinoma cells were implanted orthotopically into nude rats. ATX-S10Na(II) was injected subserosally into the primary tumor lesion, and visualized by a fluorescence spectro-laparoscope. Presence of tumor cells in lymph nodes (LNs) was determined by RT-PCR specific for human β-actin. Results: Injection of ATX-S10Na(II) was successful in 27 tumor-bearing rats. A red fluorescence was incorporated into the left gastric and hepatic LNs in 25 and 2 rats, respectively. Of note, human β-actin was detected in most of these LNs. Fluorescence was not detected in LNs that did not contain cancer. Conclusion: ATX-S10Na(II) is useful for the detection of cancer-containing SNs in an animal model of gastric carcinoma, and may serve as a novel tracer in SN navigation surgery. © 2006 Wiley-Liss, Inc.