Determination of qualitative telomerase activity as an adjunct to the diagnosis of pancreatic adenocarcinoma by EUS-guided fine-needle aspiration.
Background: Telomerase activity is up-regulated in pancreatic cancer. Hence, measurement of telomerase activity in pancreatic needle-biopsy specimens could assist in establishing a positive diagnosis in specimens that are inadequate for cytology.
Objective: To determine the sensitivity and specificity of telomerase activity for neoplasia in a series of EUS-guided fine-needle aspirate (EUS-FNA) biopsies of pancreatic mass lesions.
Methods: Prospective, consecutive, non-randomized cohort. Methods: Academic hospital, tertiary referral center. Methods: Seventy-one patients with a pancreatic mass diagnosed by cross-sectional imaging. Methods: EUS-FNA of 52 solid and 18 cystic pancreatic lesions. Methods: (1) Cytologic diagnosis; (2) tissue telomerase activity by semi-quantitative polymerase chain reaction; (3) patient demographics; (4) clinical outcomes.
Results: Cytology results were positive for adenocarcinoma in 40 patients with a solid pancreatic mass; of these, telomerase activity was detected in 31. There were no telomerase false-positive results. Telomerase results were positive in 6 of the 7 patients (86%) who had negative cytology results and who eventually were found to have biopsy-proven adenocarcinoma. The sensitivity and specificity of telomerase activity for detecting pancreatic adenocarcinoma in solid masses was 79% (95% CI, 64%-89%) and 100% (95% CI, 55%-100%).
Conclusions: Extremely high sensitivity and specificity of EUS-FNA cytology in solid lesions minimized the incremental benefit of telomerase. Conclusions: Telomerase activity can be measured readily in specimens obtained at EUS-FNA and accurately predicts malignancy. Used in combination with cytology, telomerase increased the sensitivity from 85% to 98% while maintaining the specificity at 100%. Lesions with negative cytology result and positive telomerase activity should be evaluated aggressively to exclude malignancy.