THE USE OF INTRAOPERATIVE ULTRASONOGRAPHY FOR DETECTING TUMOR EXTENSION IN BILE-DUCT CARCINOMA

The purpose of this study was to investigate the clinical feasibility of using intraoperative ultrasonography (IOUS) to detect tumor extensi on in bile duct carcinoma, especially longitudinal invasion along the bile ducts into either the hepatic parenchyma or adjacent hilar vessel s, Materials and methods. The medical records of 14 patients with bile duct carcinoma who under,vent surgical treatment at the First Departm ent of Surgery, University of the Ryukyus, were retrospectively analyz ed, All patients Here examined by IOUS during the operation, The resec ted specimens were processed in order to compare the ultrasound images with the histological findings, Results, The echo level of the primar y lesion was not consistent, Specific echo patterns, such as a thicken ing of the echogenic layer (TEL) adjacent to the main tumor showing ca ncerous invasion. were observed in ten patients, 71.4% (nodular invasi ve 7, invasive 3) which were later confirmed by microscopic examinatio ns and ultrasonic findings, The detection rate of TEL was 87.5% in nod ular invasive type and 100% in invasive type, respectively, The TEL hi stologically coincided with a layer of fibrotic hypertrophy around the infiltrating tumor cells, The intramural invasion beyond the edge of TEL was detected in only 2 out of II patients, The accurate detection rate of the involvement of the portal vein and the hepatic artery by I OUS was 83.3% and 60%, respectively. Based on the above findings, IOUS is thus considered to be essential for evaluating tumor extension alo ng the bile ducts, and also greatly helps in selection of the most app ropriate operative procedure, especially in hilar cholangiocarcinoma.