ENDOSCOPIC ULTRASONOGRAPHIC CRITERIA OF VASCULAR INVASION BY POTENTIALLY RESECTABLE PANCREATIC TUMORS

Endoscopic ultrasonography was used to examine 38 patients with a panc reatic neoplasm (mean size, 2.8 cm; range, 1 to 5 cm). Three EUS signs appear to be reliable criteria for the identification of tumor invasi on of major veins forming the portal confluence: (1) peri-pancreatic v enous collaterals in the area of a mass that obliterates the normal an atomic location of a major portal confluence vessel; (2) tumor within the vessel lumen; and (3) abnormal vessel contour with loss of the ves sel-parenchymal sonographic interface. At least one of these signs was present in each of the 21 patients with vascular invasion; none of th em was present in the 17 patients without vascular invasion. Findings were confirmed by laparotomy plus biopsy (33 patients), autopsy (1 pat ient), or angiography plus biopsy (4 patients). Arterial involvement w as identified by alteration of vessel course and caliber. All 7 patien ts with arterial involvement also had venous involvement. These signs provide reliable criteria for endoscopic ultrasonographic definition o f unresectable tumors in patients with a pancreatic neoplasm that appe ars to be resectable on standard radiologic tests.