EUS-guided FNA of solid pancreatic masses: high yield of 2 passes with combined histologic-cytologic analysis

Background: EUS-guided FNA (EUS-FNA) is an established tissue-acquisition technique, with most studies concentrating on cytologic analyses of specimens, with only few data existing on histologic assessment. Objective: To assess the sensitivity of a combined analysis of histologic followed by cytologic tissue diagnosis. Design: A retrospective 3-center study. Methods: In consecutive patients undergoing FNA of solid pancreatic masses, core specimens were harvested for histology; residual tissue was examined cytologically. Only unequivocally positive results were regarded as malignant. Criterion standards were positive results from EUS-FNA or other histologic findings, or, if negative, clinical follow-up data (minimum 12 months). Results: Among 192 patients (11.0 men; mean age 63 years) with mostly pancreatic-head masses (72.4%), overall, adequate tissue was obtained in 98.9% of all cases, with a mean of 1.88 needle passes and an overall sensitivity of 82.9% (95% Cl, 76.0%-88.5%). Histology and subsequent cytology provided adequate tissue and sensitivities of 86.5% and 60%, and 92.7% and 68.1%, respectively Excluding cases with inadequate specimens, sensitivities rose by 4% to 10%. Histology showed a trend for superiority over cytology only in characterizing nonadenocarcinoma tumor types. No differences in sensitivity were found between the centers involved. Limitations: Retrospective design, different processing of cytologic specimens. Conclusions: At EUS-FNA in pancreatic masses, combined histologic-cytologic analysis achieved a sensitivity of more than 80%, despite a low number of needle passes and may thus save time. Histology alone did not reach higher sensitivity than cytology. In particular situations, eg, rare tumors, histology may still be required. (Gastrointest Endosc 2009;70:60-9.)