Sonographic pitfalls in the diagnosis of pancreatic neoplasms

False sonographic diagnoses were analyzed in a series of 51 patients with pancreatic neoplasms. Sonography indicated 40 of these, leaving 11 cases of false-negatives. In addition, 11 cases were falsely suggested (false-positives). Sonography overlooked 15.5% of the cases when definite observer errors were excluded. Of the 22 falsely diagnosed cases, 12 had obstructive jaundice, which may have affected the diagnosis. Large tumors were detected but their origin was difficult to determine. Although sonography may be reliable in suggesting a pancreatic neoplasm, other differential diagnoses have to be taken into account as well.