False-Positive Cytology for Endoscopic Ultrasound Fine-Needle Aspiration

The false-positive rate of endoscopic ultrasound fine-needle aspiration (EUS-FNA) cytology is thought not to exceed 1%. To test that assumption, Mayo Clinic researchers prospectively compared EUS-FNA cytology findings that were positive or suspicious for malignancy or neoplasm with findings from the diagnostic gold standard of surgical pathology. Only patients who proceeded directly to surgery without neoadjuvant therapy were included. Positive or suspicious FNA cytology in the absence of malignancy or neoplasm on the subsequent surgical pathology was considered a discordant result.

Of 5667 FNAs performed during a 12.5-year period, 2547 (45%) were interpreted as positive, suspicious, or atypical for malignancy or neoplasm. A total of 377 pat…