TRANSENDOSCOPIC ULTRASOUND OF ESOPHAGEAL AND GASTRIC-CANCER USING MINIATURIZED ULTRASOUND CATHETER PROBES

Background: The aim of this study was to investigate the value of mini aturized ultrasound catheter probes (miniprobes) for preoperative stag ing of esophageal and gastric cancer. Methods: Fifty-one patients with esophageal (n = 21) and gastric cancer (n = 30) underwent endoscopic ultrasound (EUS). All examinations were carried out using mechanical m iniprobes (diameter 6F, 12.5 MHz) that were introduced through the ins trument channel of the endoscope. Results: EUS with miniprobes was suc cessfully performed in all patients, although stenotic tumors, which c ould not be traversed with the endoscope, were found in 6 of 21 patien ts (29%) with esophageal cancer. Miniprobe scanning provided high-reso lution images of the gastrointestinal tract. The overall accuracy in t he assessment of tumor infiltration depth for esophageal and gastric c ancer was 90% and 82%, respectively. However, the value of miniprobe s canning in the assessment of advanced tumors was limited by the imagin g depth of the probe (approximately 3 cm). Lymph node involvement was accurately diagnosed in 78% of the patients with esophageal cancer (se nsitivity 75%, specificity 80%) and in 80% of the patients with gastri c cancer (sensitivity 73%, specificity 89%).Conclusions: EUS with mini probes can be performed as single-step procedure during diagnostic end oscopy. The 12.5 MHz transducer provides high-resolution imaging and e nables accurate staging of tumors with limited infiltration depth.