PurposeEndoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is the most reliable method for the histological diagnosis of pancreatic tumors. Rapid on-site fluorescence-guided histological diagnosis was evaluated by topically applying an enzymatically activatable probe onto the EUS-FNA samples; the probe fluoresces in the presence of γ-glutamyltranspeptidase (GGT).ProceduresWe evaluated GGT expression in pancreatic cancer cell lines in vitro. EUS-FNA was performed in 10 pancreatic tumors. After topical application of the probe, signal intensity was measured using a fluorescence imaging system for 13 min.ResultsGGT was expressed in Panc-1, AsPC-1, and AR42J, but not in KP4 cells. In samples from six cases, several regions of the specimens fluoresced and contained adequate tissue for pathological diagnosis. The remaining four non-fluorescent samples contained very small amounts of carcinoma, normal epithelial cells, or no epithelial cells. The signal intensity at 5 min was 25.5?±?7.7 and 7.7?±?0.5 in fluorescent and non-fluorescent regions, respectively (p?<?0.05).ConclusionsApplication of enzymatically activatable probe onto EUS-FNA samples would be feasible for the rapid evaluation of tissues suitable for histological diagnosis. |