Findings after ultrasound-guided fine needle ago-biopsy (FNAB) in suspected pancreatic lesions

Introduction: Pancreatic cancer is the fifth most common cause of cancer death in the Western hemisphere. It may present with few, or a short history of, symptoms, and has been called the ''silent killer'' because of the late clinical symptoms and rapid growth, and a median survival of less than 6 months. Pancreatic masses may be solid or cystic, benign or malignant. Thus differentiation of benign from malignant solid or cystic pancreatic masses is often difficult. Ultrasound-guided FNAB is a diagnostic tool characterized by simplicity, quickness of execution, high precision of sample and low cost.

Aim: To assess the prevalence of different type of pancreatic lesions using ultrasound-guided FNAB biopsy.

Methods: One hundred and twelve patients with suspected pancreatic lesions at imaging studies, referred to our hospital between May 1998 and June 2007, were enrolled in the study. Percutaneous fine needle aspiration biopsy (FNAB) was performed with the help of a multidisciplinary ultrasound system guidance. The usual approach was frontal, crossing prepancreatic structures, left liver lobe, enteral loops pyloric vestibule. Diagnosis was confirmed either by histopathology or exploratory laparotomy, by follow-up data in rest of the cases.

Results: One hundred and twenty cytological samples were collected on 112 patients (61 males and 51 females) with a mean age of 64. In doubtful cases the test was repeated. The diagnosis obtained after biopsy were: pseudocyst (4), cyst (2), chronic pancreatitis (4), adenomatous hyperplasia (3), polimorphous adenoma (5), papillary adenoma (3), lymphoma (2), adenocarcinoma (69), secondary localizations (7), neuroendocrine cancer (3). The correlation with the definitive diagnosis obtained at exploratory laparatomy, autopsy or follow-up was good (k=0.76). In 5 cases (4%), cytological sample were inadequate, 5 (4%) were negative and 8 (7%) were doubtful. There were complications in one case of asymptomatic peripancreatic hematoma, which resolved spontaneously, two cases of vaso-vagal reactions, and 11 cases of pain.

Conclusion: The high frequency of adenocarcinoma diagnosis underlines the importance of performing a biopsy in case of suspected pancreatic lesions. Moreover, FNAB demonstrates a very good reliability and safety, a high grade of diagnostic accuracy and, finally, a very good specificity.