The accuracy of EUS and helical CT in the assessment of vascular invasion by peripapillary malignancy

Background: The relative accuracy of helical CT and EUS for defining the lo cal resectability of peripapillary malignancies is undefined. Methods: Fifty-one patients with a peripapillary malignancy and no metastat ic disease were prospectively evaluated with helical CT and EUS. Imaging re sults were compared with surgical staging, and a tumor was defined as resec table when there was no macroscopic or microscopic residual tumor. Results: Nine patients had surgically confirmed locally unresectable diseas e, which was accurately predicted by EUS in 6 patients (sensitivity 67%) an d by helical CT in 3 patients (sensitivity 33%; p = 0.35). When only patien ts with complete EUS examinations were included, the sensitivities of EUS a nd helical CT for vascular invasion were 100% and 33% (p = 0.06), respectiv ely. When all patients not undergoing surgery because of imaging evidence o f locally unresectable disease were included, the sensitivities were 100% a nd 62.5% (p = 0.02), respectively. One of 15 patients with a tumor amenable to surgical resection was labeled as unresectable by EUS but subsequently had a local recurrence of the tumor. The specificities of EUS (93%) and hel ical CT (100%) were similar. Conclusion: EUS is more sensitive than helical CT for detecting vascular in vasion by peripapillary malignancies and should be added to staging protoco ls, particularly when findings on helical CT are equivocal.