Correlation of endoscopic ultrasonography (EUS) for differential diagnostics between inflammatory and neoplastic lesions of the papilla of Vater and the peripapillary region with results of histologic investigation.

PURPOSE: There is currently no imaging procedure that allows precise differentiation between inflammatory and malignant lesions of the papilla of Vater (papilla) in a satisfying manner. The aim was to study whether endoscopic ultrasonography (EUS) as an initial diagnostic step 1. may have the potential to distinguish between different tissue characteristics, such as tumor growth or inflammation of the papilla, because of its high resolution capacity and 2. is superior to the accuracy of histologic investigations of mucosal biopsies by means of a prospective collection and retrospective evaluation of the data. PATIENTS AND METHODS: Between 1995 and 2002, a significant pathologic finding in the papilla and the peripapillary region was revealed using EUS in 311 patients (overall, 4,832 EUS investigations); the comparison of this suspicion with the results of histologic investigation was only possible in 183 subjects. In 133/183 patients, a biopsy for histologic investigation was not able to be obtained prior to the use of EUS. Diagnosis was set up using EUS, which tried to differentiate between benign or malignant lesions of the papilla. Histologic investigation of the 133 tumor lesions of the papilla became possible by taking deep transpapillary biopsies following papillotomy, papillectomy or by obtaining specimens from surgical resections.
RESULTS: Using EUS, differentiation between inflammatory and neoplastic lesions of the papilla or the peripapillary region was correct in 109 of 133 cases (82%), while suspected EUS-based diagnosis "papillitis stenosans" (inflammatory lesions of the papilla of Vater) in 4 subjects (3%) was corrected to adenoma and carcinoma, respectively (n=2 each) by histologic investigation. In 20 of 133 patients with suspected neoplastic lesions, inflammatory lesion of the papilla of Vater was detected resulting in an overall sensitivity of 92.3% and specificity of 75.3%.
CONCLUSIONS: EUS makes it possible to detect small intraampullary tumors and segmental thickening of the wall of the prepapillary biliary duct, which cannot be revealed by conventional imaging. In patients with biliary symptoms, EUS can reliably visualize and characterize a malignant lesion as a first diagnostic tool (detection rate, 82%) and may be considered the basis for subsequent diagnostic steps for verifying diagnosis correctly, e. g., using histologic investigation.