The role of endoscopic ultrasound (EUS) in relation to other imaging modalities in the differential diagnosis between mass forming chronic pancreatitis, autoimmune pancreatitis and ductal pancreatic adenocarcinoma

Abstract

Differential diagnosis of solid pancreatic lesions remains as an important clinical challenge, mainly for the differentiation between mass forming chronic pancreatitis, autoimmune pancreatitis and pancreatic adenocarcinoma. Endoscopic ultrasound (EUS), computed tomography (CT) and magnetic resonance imaging (MRI) can all provide valuable and complementary information in this setting. Among them, EUS has the unique ability to obtain specimens for histopathological diagnosis and can therefore play a crucial role in the evaluation patients with inconclusive findings on initial examinations. Nowadays, new developed techniques associated to EUS, like elastography and contrast enhancement, have shown promising results for the differential diagnosis of these pancreatic lesions.Key words: Endoscopic ultrasound. CT scan. MRI. Pancreatic tumors. INTRODUCTIONDifferential diagnosis of solid pancreatic masses remains a challenge, despite recent advances in different diagnostic procedures. In this article, the role of endoscopic ultrasound (EUS) including EUS-guided FNA, elastography and contrast enhancement will be reviewed in relation to computer tomography (CT), magnetic resonance tomography (MRI) and magnetic resonance cholangiopancreatography (MRCP). Differential diagnosis between malignant lesions and mass-forming chronic pancreatitis or focal autoimmune pancreatitis will be discussed. Tumor staging and evaluation of resectability of these pancreatic lesions will not be evaluated. Other imaging techniques, like PET-scan or octreoscan will not be analyze, because their usefulness in this context is unclear.Differential diagnosis between malignant pancreatic lesions (pancreatic cancer, pancreatic metastasis) and massforming chronic pancreatitis CT scan is the most widely spread imaging modality for evaluation of pancreatic solid masses and considered as the most comprehensive tool for diagnosis and surgical staging of pancreatic malignancies (1). CT technology has significantly advanced over the last years, multidetector helical CT scan allows for very thin sliced cuts, providing a higher image resolution and faster image acquisition (Fig. 1) Vol. 104. N.° 6, pp. 315-321, 2012 Disclosures: Dr. Julio Iglesias-García is international advisor of Cook-Medical. Dr. J. Enrique Domínguez-Muñoz is international advisor of Pentax Medical Company.Received: 27-03-201227-03- Accepted: 20-04-2012 Correspondence: Julio Iglesias-García. Department of Gastroenterology.

The integration of single fiber reflectance (SFR) spectroscopy during endoscopic ultrasound-guided fine needle aspirations (EUS-FNA) in pancreatic masses: a feasibility study

“…3 The sensitivity and accuracy for malignancy range from 75-92% and from 79-92%, respectively. 5 However, the sensitivity drops to 54% in patients with chronic pancreatitis 6 , and the negative predictive value was estimated at 60-70% in a systematic review 7 .…”

“…4 For the diagnosis and staging of pancreatic cancer, a contrast enhanced computed tomography (CT) scan is the imaging modality of choice. 5 Endoscopic ultrasound fine needle aspiration (EUS-FNA) is also used to diagnose pancreatic lesions; it combines ultrasound imaging with cytological findings. It is useful when nothing is seen on CT, but pancreatic cancer is suspected, and it is also required when tissue diagnosis is needed before the start of radiation or chemotherapy.…”

Endoscopic Ultrasound for the Diagnosis of Chronic Pancreatitis

“…Pancreatic calcification and dilatation of the pancreatic duct are characteristics findings of CP on noninvasive imaging studies, such as computed tomography (CT) and magnetic resonance imaging (MRI) (14). Although the latter are considered modalities of choice, endoscopic ultrasound (EUS) is now also viewed as one of the most sensitive methods for detecting pancreatic lesions, given the close proximity of the transducer to the pancreas (4,21,27,28). Since 1986, there have been numerous studies reporting the use of endoscopic ultrasound for the diagnosis of chronic pancreatitis.…”

“…In EUS studies of the pancreas, non-homogenous changes of parenchyma, particularly hyperechoic foci or strands, lobulation, calcifications, and cysts, and ductal alterations, including a hyperechoic wall, dilatation and/or tortuosity of the main duct, intraductal hyperechoic foci, and ectatic side branches are grounds for a diagnosis of CP (4,21,27,28). The severity of CP (mild, moderate, severe) may also be gauged accordingly (21), although standardized diagnostic guidelines have yet to be adopted.…”

“…The severity of CP (mild, moderate, severe) may also be gauged accordingly (21), although standardized diagnostic guidelines have yet to be adopted.…”