18F-FDG PET/CT imaging in the workup of cardiac and pericardial masses

CARDIAC TUMORS: UPDATED CLASSIFICATIONS AND MAIN CLINICO-PATHOLOGIC FINDINGS

This review article - which is devoted to a wide range of physicians, e.g., pathologists, clinicians, radiologists, and general practitioners - is an up-to-date clinico-pathological description of cardiac tumours. Although rare, cardiac tumours are key components in oncology practice since both their early diagnosis and appropriate management denote urgent needs. Primary cardiac tumours (PCTs) are categorized in recent WHO classifications as well as in other scientific contributions. Their incidence is around 0.02% while their prevalence is between 0.001% and 0.03%. Among PCTs, benign lesions account for 85% of cases, while malignant neoplasms for 15%. Compared to PCTs, secondary cardiac tumours are 20-30-fold more common. The most frequent PCTs in adulthood are papillary fibroelastoma and cardiac myxoma, while, in childhood, cardiac rhabdomyoma. Heart metastases may occur through direct extension, or, indirectly, via bloodstream, lymphatics or intracavitary diffusion. Thoracic cancers (e.g. from pleura, lung, breast) are the most frequent cause of cardiac metastasis followed by oesophageal and haematological malignancies. Symptoms of PCTs (e.g. arrhythmias, dyspnoea, chest discomfort, syncope) are usually the result of both their regional involvement and location. Non-invasive imaging techniques (e.g. echocardiography, MRI, CT) and biopsy are key means in delineating tumour characteristics, size, and adjacent structure involvement. Most PCTs require surgery, which is recommended to prevent life-threatening complications. While many benign cardiac neoplasms may be completely resected, the treatment of choice for malignant PCTs and metastases is a combination of surgery, radio- and/or chemotherapy, as well as new alternative treatments, which may prolong survival in a small patient subset.

Hybrid cardiovascular imaging. A clinical consensus statement of the european association of nuclear medicine (EANM) and the european association of cardiovascular imaging (EACVI) of the ESC

Hybrid imaging consists of a combination of two or more imaging modalities, which equally contribute to image information. To date, hybrid cardiovascular imaging can be performed by either merging images acquired on different scanners, or with truly hybrid PET/CT and PET/MR scanners. The European Association of Nuclear Medicine (EANM), and the European Association of Cardiovascular Imaging (EACVI) of the European Society of Cardiology (ESC) aim to review clinical situations that may benefit from the use of hybrid cardiac imaging and provide advice on acquisition protocols providing the most relevant information to reach diagnosis in various clinical situations.

Scope of PET imaging in the evaluation of cardiac tumors

Cardiac and pericardial masses can be categorized as neoplastic (either benign or malignant), non-neoplastic (such as thrombus or pericardial cysts), or normal variants of the cardiac structure. Diagnosing these masses can be challenging, and various imaging modalities are available, with each of them having advantages and pitfalls. Echocardiography is typically the first test used for the evaluation and detection of cardiac masses, as it is widely accessible, portable, and provides a comprehensive assessment of cardiac function and valves without the use of ionizing radiation. However, it may not be helpful in some cases, such as evaluating the extracardiac extension of the mass or characterizing tissue. On the other hand, cross-sectional imaging can provide a three-dimensional data set with excellent spatial resolution. Still, it requires ionizing radiation and intravenous iodinated contrast, and its functional evaluation of the heart may be relatively limited. 18F-FDG PET/CT helps determine 18F-FDG PET/CT is a crucial molecular imaging modality to assess and differentiate benign and malignant cardiac tumors noninvasively and helps in treatment planning and prognostication. Currently, studies evaluating the role of 18F-FDG PET/CT in cardiac tumors are limited to case reports and single center studies.

Review of cardiovascular imaging in the Journal of Nuclear Cardiology 2022: positron emission tomography, computed tomography, and magnetic resonance

In 2022, the Journal of Nuclear Cardiology® published many excellent original research articles and editorials focusing on imaging in patients with cardiovascular disease. In this review of 2022, we summarize a selection of articles to provide a concise recap of major advancements in the field. In the first part of this 2-part series, we addressed publications pertaining to single-photon emission computed tomography. In this second part, we focus on positron emission tomography, cardiac computed tomography, and cardiac magnetic resonance. We specifically review advances in imaging of non-ischemic cardiomyopathy, cardio-oncology, infectious disease cardiac manifestations, atrial fibrillation, detection and prognostication of atherosclerosis, and technical improvements in the field. We hope that this review will be useful to readers as a reminder to articles they have seen during the year as well as ones they have missed.

Expert review for clinical and translational imaging actionable imaging findings in the daily PET/CT scenario

Background and aim

The American College of Radiology (ACR) defines "actionable findings" the ones requiring a special communication between radiologists and referring clinicians, suggesting to organize their categorization in a three-degree scale on the basis of the risk for the patient to develop complications. These cases may fall in a grey-zone communication between different care figures with the risk of being underestimated or even not being considered at all. In this paper, our aim is to adapt the ACR categorization to the most frequent actionable findings encountered when reporting PET/CT images in a Nuclear Medicine Department, describing the most frequent and relevant imaging features and presenting the modalities of communication and the related clinical interventions that can be modulated by the prognostic severity of the clinical cases.

Materials and methods

We performed a descriptive, observational and critical analysis of the most relevant literature on the topic of "actionable findings", in particular, starting from the reports of the ACR Actionable Reporting Work Group, we categorised and described, in a narrative review, the most relevant "actionable findings" encountered in the Nuclear Medicine PET/CT daily practice.

Results

To the best of our knowledge, to date there are no clear indications on this selective PET/CT topic, considering that the current recommendations target mainly radiologists and assume a certain level of radiological expertise. We resumed and classified the main imaging conditions under the term of "actionable findings" according to the corresponding anatomical districts, and we described their most relevant imaging features (independently of PET avidity or not). Furthermore, a different communication timing and strategy was suggested on the basis of the findings' urgency.

Conclusion

A systematic categorization of the actionable imaging findings according to their prognostic severity may help the reporting physician to choose how and when to communicate with the referring clinician or to identify cases requiring a prompt clinical evaluation. Effective communication is a critical component of diagnostic imaging: timely receipt of the information is more important than the method of delivery.