FDG PET for imaging pericardial manifestations of Hodgkin lymphoma

Intracardiac melanoma metastases on 18F-FDG PET-CT-a case report and review of literature with imaging features

Cutaneous malignant melanoma is one of the few malignancies that can metastasize to the heart. It is important not to miss cardiac metastases on imaging as they are often clinically asymptomatic, but if present and undiagnosed could lead to significant cardiac compromise, arrhythmias, congestive heart failure, cardiac tamponade or transient ischaemic attacks.

Identifying intracardiac metastases on imaging often requires a multimodality approach as they can evade detection due to cardiac motion artefact; be confused with intracardiac thrombus, or be misinterpreted as a normal/anatomical finding.

We present an interesting case report of asymptomatic intracardiac melanoma metastases, initially identified on staging 18-fludeoxyglucose positron emission tomography-CT and eventually confirmed on cardiac MRI. The latter was able to differentiate myocardial metastases from tumour thrombus. We also review the relevant literature.

Imaging features of extranodal involvement in paediatric Hodgkin lymphoma

Detecting extranodal disease in paediatric Hodgkin lymphoma is of great importance for both treatment and prognosis. Different imaging techniques can be used to identify these extranodal sites. This pictorial essay provides an overview of imaging features of extranodal disease manifestation in paediatric Hodgkin lymphoma.

Surgery for Tumors of the Heart

Most surgeons will encounter only a handful of primary cardiac tumors outside of myxomas. Approximately 3 quarters of primary cardiac tumors are benign and 1 quarter is malignant. In most cases, cardiac tumors are silent but when symptoms do occur, they are primarily determined by tumor size and anatomical location, not by histopathology. The diagnosis and preoperative imaging relies heavily on multimodal imaging including echocardiography, computed tomography, magnetic resonance imaging, and coronary angiography. Surgical resection is the most common treatment for most simple primary cardiac tumors and for some complex benign tumors. Surgical resection of primary cardiac tumors frequently involves the need for complex cardiac reconstruction, particularly when malignant. Secondary tumors to the heart are 30 times more frequent than primary cardiac tumors, and their incidence is increasing, largely as a result of advances in cancer diagnosis and therapy. Surgical resection is feasible in only a small fraction of highly-selected patients with secondary tumors to the heart. For complex benign tumors-such as paraganglioma or large fibromas-and all primary and secondary malignant tumors, a multidisciplinary cardiac tumor team review in experienced centers of excellence is recommended.

A rare presentation of acute heart failure secondary to aggressive uterine leiomyosarcoma metastatic to the myocardium initially diagnosed as hypertrophic obstructive cardiomyopathy

Uterine sarcoma is the cause of 3-9% of all uterine malignant neoplasms and has a 2-fold higher incidence in black women as compared to white women. Cellular atypia and abundant mitoses (≥10 per 10 high power fields) as seen in this patient are associated with an increased risk for metastases. Metastases to the heart are infrequently reported with a handful of cases in the literature. We present a case of a 51-year-old woman with aggressively metastatic uterine leiomyosarcoma causing acute heart failure 4 months after initial presentation.

How to differentiate benign versus malignant cardiac and paracardiac 18F FDG uptake at oncologic PET/CT

Patients undergoing 2-[fluorine 18]fluoro-2-deoxy-d-glucose (FDG) whole-body oncologic positron emission tomography (PET)/computed tomography (CT) are studied while fasting. Cardiac FDG uptake in fasted patients has been widely reported as variable. It is important to understand the normal patterns of cardiac FDG activity that can be seen in oncologic FDG PET/CT studies. These include focal and regional patterns of increased FDG myocardial activity. Focal activity can be observed in papillary muscles, the atria, the base, and the distal anteroapical region of the left ventricle. Regional increased cardiac FDG activity may be diffuse or localized in the posterolateral wall or the base of the left ventricle. Abnormal patterns of cardiac FDG activity not related to malignancy include those associated with lipomatous hypertrophy of the interatrial septum, epicardial and pericardial fat, increased atrial activity associated with atrial fibrillation or a prominent crista terminalis, cardiac sarcoidosis, endocarditis, myocarditis, and pericarditis. Knowledge of these patterns of cardiac FDG activity is important to be able to recognize malignant disease involving the paracardiac spaces, myocardium, and pericardium. With a better understanding of the range of normal and abnormal patterns of cardiac FDG activity, important benign and malignant diseases involving the heart and pericardium can be recognized and diagnosed.

FDG PET/CT of extranodal involvement in non-Hodgkin lymphoma and Hodgkin disease

The term extranodal disease refers to lymphomatous infiltration of anatomic sites other than the lymph nodes. Almost any organ can be affected by lymphoma, with the most common extranodal sites of involvement being the stomach, spleen, Waldeyer ring, central nervous system, lung, bone, and skin. The prevalence of extranodal involvement in non-Hodgkin lymphoma and Hodgkin disease has increased in the past decade. The imaging characteristics of extranodal involvement can be subtle or absent at conventional computed tomography (CT). Imaging of tumor metabolism with 2-[fluorine-18]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) has facilitated the identification of affected extranodal sites, even when CT has demonstrated no lesions. More recently, hybrid PET/CT has become the standard imaging modality for initial staging, follow-up, and treatment response assessment in patients with lymphoma and has proved superior to CT in these settings. Certain PET/CT patterns are suggestive of extranodal disease and can help differentiate tumor from normal physiologic FDG activity, particularly in the mucosal tissues, bone marrow, and organs of the gastrointestinal tract. Familiarity with the different extranodal manifestations in various locations is critical for correct image interpretation. In addition, a knowledge of the differences in FDG avidity among the histologic subtypes of lymphoma, appropriate timing of scanning after therapeutic interventions, and use of techniques to prevent brown fat uptake are essential for providing the oncologist with accurate information.

Intracardiac Extension of Lung Cancer Demonstrated on PET Scanning

Intracardiac tumors are unusual and can originate within the heart or spread from other sites. This is a report of a patient who presented with a TIA, and during the subsequent stroke workup, a right hilar nonsmall cell lung carcinoma was discovered. The tumor had extended into the left atrium through a pulmonary vein. The hilar tumor as well as intracardiac extension were demonstrated by PET scanning using FDG.