False-positive EUS-guided FNA cytology for solid pancreatic lesions

• Published in: Gastrointestinal endoscopy Vol. 74; no. 3; pp. 535 - 540
• Main Authors: Siddiqui, Ali A., MD, Kowalski, Thomas E., MD, Shahid, Haroon, MD, O'Donnell, Sean, MD, Tolin, Joanna, MD, Loren, David E., MD, Infantolino, Anthony, MD, Hong, Shih-Kuang, MD, Eloubeidi, Mohamad A., MD
• Format: Journal Article
• Language: English
• Published: Maryland heights, MO Mosby, Inc 01.09.2011; Elsevier
• Subjects: Adenocarcinoma - pathology; Adenocarcinoma - surgery; Adult; Aged; Aged, 80 and over; Biological and medical sciences; Biopsy, Fine-Needle; Digestive system. Abdomen; Endoscopy; False Positive Reactions; Female; Gastroenterology and Hepatology; Gastroenterology. Liver. Pancreas. Abdomen; Humans; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Middle Aged; Neuroendocrine Tumors - pathology; Neuroendocrine Tumors - surgery; Pancreas - pathology; Pancreatic Neoplasms - pathology; Pancreatic Neoplasms - surgery; Pancreatitis, Chronic - pathology; Retrospective Studies; Statistics, Nonparametric; Ultrasonography, Interventional; FP; false positive; EUS-FNA; EUS-guided FNA; Sonography; Fine needle; False positive; Endoscopic route; Endoscopic ultrasonography; Cytology; Echography; Lesion; Pancreas; Aspiration punction
• ISSN: 0016-5107; 1097-6779
• DOI: 10.1016/j.gie.2011.04.039

Background The currently accepted paradigm is that the false-positive (FP) rate for EUS-guided fine-needle aspiration (EUS-FNA) cytologic analysis of a pancreatic lesion is less than 1%. Objective To assess the FP rate of EUS-FNA in patients who underwent surgical resection for presumed pancreatic cancer. Design Retrospective study. Setting Tertiary-care referral center. Patients This study involved 367 patients with solid pancreatic lesions in whom EUS-FNA cytology results were interpreted as positive or suspicious for malignancy, which resulted in subsequent surgical resection. Intervention Surgical resection. Main Outcome Measurements The FP diagnosis was defined as EUS-FNA cytology specimens being reported as “positive” or “suspicious for malignancy” but that were later proven to be benign on surgical pathology. Results The FP rate for EUS-FNA was 4 of 367 (1.1%) when only “positive” cytology findings were interpreted as malignant and 14 of 367 (3.8%) when both suspicious and positive cytology findings were interpreted as malignant. Among the 4 cases falsely interpreted as positive, 1 was falsely diagnosed cytologically as a neuroendocrine tumor and 3 as adenocarcinomas. All FP specimens showed chronic pancreatitis on surgical pathology. The incidence of discordance between cytology and surgical pathology did not change over time (2000-2006: 8/188 [4.3%] vs 2007-2010: 6/179 [3.4%]; P = .79). Limitations Retrospective study at a single center. Conclusion In a retrospective cohort trial, the FP rate for EUS-FNA of solid pancreatic lesions was 1.1%. Findings of the current study are in line with previous studies that have evaluated the FP cytology rates with EUS-FNA of solid lesions. FP cases transpired primarily as a result of cytologic misinterpretation in the setting of chronic pancreatitis.