Abstract
INTRODUCTION: Solid pancreatic lesions (SPL)s can be due to various etiologies, and their management depends on the histologic diagnosis. AIM: The aim of this study was to document the etiology, morphology, and utility of macroscopic on-site evaluation (MOSE) in predicting good yield of endoscopic ultrasound (EUS)-guided biopsy. MATERIAL AND METHODS: All patients with SPLs referred for EUS-guided biopsy were included in the study. Etiology, morphology and results of EUS-guided biopsy were recorded. Rapid on-site evaluation (ROSE) was not available; therefore, MOSE was performed by an endoscopist. Macroscopically, MOSE was considered satisfactory if at least 1 tissue core at least 1 inch long was secured. Histopathologically, a biopsy specimen was considered to have a good yield if it was sufficient to establish a diagnosis. Factors predicting good yield of biopsy (GYB) were identified. RESULTS: Of the total 176 patients included in the study, 111 (63.1%) were male (mean age 53.8 (±12.6) years; range: 14-80 years). Good yield biopsies (GYB) numbered 144 (81.8%); among them, 97 (67.4%) were neoplastic and 47 (32.6%) non-neoplastic SPLs. The commonest neoplastic SPLs were pancreatic ductal adenocarcinoma (PDA) (76; 78.3%), neuroendocrine tumors (NETs) (13; 13.4%), metastasis (5; 5.1%), and others (3; 3.1%), while the commonest non-neoplastic SPLs were mass-forming chronic pancreatitis (MFCP) (33; 70.2%), autoimmune pancreatitis (AIP) (5; 10.6%), and tuberculosis (2; 4.3%). PDAs were more common in older patients (65/76; 85.5%) and in the head region of the pancreas (47; 61.8%), while NETs were more common in younger patients 7/13 (53.8%) and in the body of the pancreas 5/13 (38.5%). Factors predicting GYB were SPL size > 15 mm (p = 0.045), use of fine needle biopsy (FNB) needles (p = 0.001), ≥ 2 passes (p = 0.001), and satisfactory MOSE (p ≤ 0.0001) on univariate analysis; and FNB use (p = 0.049) and satisfactory MOSE (p = 0.001) on multivariate analysis. Our criteria for satisfactory MOSE had high sensitivity (85.4%), positive predictive value (95.35%), and diagnostic accuracy (84.7%). CONCLUSIONS: The commonest neoplastic SPLs are PDA and NET, and the commonest non-neoplastic SPLs are MFCP and AIP. PDAs have a predilection for the head region and older age, while NETs have a predilection for younger patients and the body of the pancreas. A good biopsy yield is likely with use of FNB needles and satisfactory MOSE.