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

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 beta-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 beta-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.