Abstract
Background and Study Aims: Endoscopy and biopsy from a suspicious Vater's papilla may establish an early preoperative
diagnosis of a periampullary tumor. However, information regarding the diagnostic
accuracy of this procedure is limited and variable. The aim of the present study was
to evaluate retrospectively the accuracy of this procedure compared to that of other
diagnostic methods.
Patients and Methods: Among 928 patients referred to our institute for endoscopic retrograde cholangiopancreatography
(ERCP), a suspicious Vater's papilla was seen in 28. In each case comparison was made
between the pre-ERCP clinical diagnosis, endoscopic appearance, histologic interpretation
of endoscopic biopsies, and the final diagnosis. Two patients in whom a final diagnosis
was not available were excluded from the study.
Results: A final diagnosis of an ampullary or periampullary carcinoma was established in 17
patients (65 %), a carcinoma within an adenoma of the papilla in three patients (12 %),
and adenoma and a metastatic gallbladder carcinoma in one patient each. The remaining
four patients (15 %) were finally diagnosed as having "pseudotumors" (due to choledocholithiasis).
Eight (38 %) of the 21 patients with ampullary or periampullary neoplasm also had
gallstones. A pre-ERCP diagnosis (by clinical evaluation and non-invasive imaging)
of tumor versus choledocholithiasis was accurate in only 65 % of all 26 patients.
In these, the diagnostic accuracy of endoscopic appearance and endoscopic biopsy was
77 % and 85 %, respectively. Regarding the 21 patients with carcinomas, the diagnosis
by endoscopic appearance was more accurate than that by endoscopic biopsy (90 %vs
81 %). Unlike the positive predictive values, the negative predictive values for malignancy
were weak: 33 % for the endoscopic appearance and 50 % for the endoscopic biopsy.
Conclusions: Because of a high incidence of concurrent cholelithiasis, many patients with a periampullary
tumor seen during ERCP are misdiagnosed earlier (by clinical evaluation and non-invasive
imaging) as having choledocholithiasis only. However, the accuracy of endoscopy and
biopsy is also limited. This limitation must be considered when evaluating the optimal
management of patients with suspected periampullary tumor.
