Learning objectives

Objectives

To review and illustrate the main features and imaging findings of the primary hepatic lymphoma, and to demonstrate clues for the differential diagnosis including main potential mimickers. Presentation will cover the spectrum of primary liver lymphoma-FLL based on multimodality evaluation in eight cases from our hospital database with diagnostic confirmation.

Background

Lymphoma with liver involvement may be seen with or without concomitant nodal disease and classified as primary or secondary forms. Primary hepatic lymphoma is a rare clinical condition, and contrast-enhanced CT/MR may unexpectedly point out to other differentials precluding the correct diagnosis.

Imaging findings OR Procedure findings

Hepatic lymphoma may depict a single, large FLL, or present with multiple parenchymal FLL, obliging to rule out peliosis, abscesses, tuberculosis, sarcoidosis and/or infiltrative forms of hepatocellular carcinoma. Generally hypodense after contrast media administration our cases will also cover the less typical hypervascular FLL in this clinical context.

Conclusion

Definitive diagnosis of primary hepatic lymphoma should be complemented by pathological examination in order to avoid pitfalls and postpone or apply wrong therapeutical decisions.We hope to increase the radiologist awareness for this infrequent clinical condition making the diagnosis more expeditious.

Objectives

- Describe and highlight the most important features of liver vascular anatomy;

- Review and classify the different disorders that may affect hepatic vascularization, focusing on the imaging features that allow their diagnosis;

Background

The liver is a unique organ with a dual blood supply (the portal vein and the hepatic artery) and a single outflow via the hepatic veins. There are several anastomoses between the hepatic artery and the portal vein, allowing a delicate autoregulation of the blood inflow.

Imaging findings OR Procedure findings

In this review we were able to demonstrate different causes of liver vascular disorders, focusing on the mechanisms and imaging findings that allow the correct diagnosis.

Hepatic vascular abnormalities were divided according to the affected vessel: portal vein – leading to decreased portal flow such as in thrombosis, compression or arterio-portal shunts; hepatic artery – decreased flow (due to stenosis, thrombosis or infarction), increased flow or in aneurysms of this vessels; hepatic vein – as in Budd-Chiari syndrome, Veno-occlusive syndrome, right sided heart failure, among other diseases; intrahepatic vascular communications.

Conclusion

Knowledge of the liver vascularization and the compensatory mechanisms that develop after each hepatic vascular disorder are important in order to understand and diagnose very frequent pathologies that the radiologist may face in the clinical practice.

Objectives

The purpose of this education exhibit is to review typical and atypical imaging features of pancreatic neuroendocrine tumors (PNETs) on contrast enhanced computed tomography (CT) and magnetic resonance imaging (MRI) and to discuss new updates in the grading and staging systems.

Background

PNETs are rare and represent a heterogeneous group of tumors in their pathologic, clinic and imaging features. These have different prognoses depending on WHO and pTNM classifications.

The role of imaging includes localization of small functioning tumors, identification of signs of malignancy, assessment of disease extent and differentiation from other lesions such as adenocarcinoma or metastasis.

Imaging findings OR Procedure findings

Morphological imaging, such as CT and MRI, are the most widely used techniques to initially detect and stage these lesions.

PNETs have a broad spectrum of appearance. At CT and MRI, most functioning PNETs typically present as small, well-defined lesions, with intense and homogeneous enhancement in the arterial and portal phases. However, some PNETs with more fibrous content may have a later enhancement, which is better illustrated on the delayed phases. Other findings also found are cystic changes and calcifications. Non-functioning PNETs are generally larger with less intense and more heterogeneous enhancement.

Conclusion

PNETs are rare neoplasms and they can present a diagnostic challenge, both clinically and radiologically.

Imaging contributes greatly to patient care and is crucial in the detection and characterization of primary lesions, staging and subsequent follow-up.

Learning objectives