Precursors Lesions of Pancreatic Cancer: A Current Appraisal on Diagnosis

Abstract: The dramatic increase in the number of patients diagnosed with incidental pancreatic cysts through imaging methods provides a unique opportunity to detect and treat these precursor lesions of ductal adenocarcinoma before their manifestation. However, without any reliable biomarkers, the cost-effectiveness and the limited accuracy of high resolution imaging techniques for diagnose and staging seems troublesome. Small pancreatic cysts can be easily detected, but many are clinically irrelevant and are not harmful to the patient. Furthermore, patients with clinically benign lesions are at high risk of overtreatment and morbidity and mortality from unnecessary surgical intervention. It is believed that cyst fluid analysis may provide important information for a possible diagnosis, allowing stratification and treatment of these patients. Anyway, only the logical reasoning based on all available information (medical history, imaging, and laboratory analysis of the aspirated cyst fluid) can adequately stratify patients. It has been considered that there are three precursor lesions of the pancreatic cancer (PC): mucinous cystadenoma (MCA), intraductal papillary mucinous tumor (IPMT) and pancreatic intraepithelial neoplasia (PanIN). MCA and IPMT can be diagnosed by imaging methods, but PanIN are difficult to be identified. They must be detected and treated as soon as possible, as this is the only way to increase survival and reduce mortality of pancreatic ductal adenocarcinoma. The aim of this work is to establish diagnosis, staging, and the pathological findings and to compare the effectiveness and accuracy of the other imaging methods versus endoscopic ultrasound guided fine-needle aspiration (EUS-FNA) for
diagnosis of malignancy in the precursor lesions of pancreatic cancer.