Incidental cardiac findings on somatostatin receptor PET/CT: What do they indicate and are they of clinical relevance?

Entela Bollano,Niklas Bergh,Anders Bergström,Anna Dudás,Daniela Esposito,Marie Björkenstam,Amar Taha,Kristjan Karason,Emanuele Bobbio,Oskar Angerås,Martijn van Essen,Christian L. Polte

doi:10.1007/s12350-021-02526-9

Abstract

We present the case of a 47-year-old man with a history of recurrent episodes of frontal headache, fever, and chest discomfort as well as longstanding, difficult to treat arterial hypertension. Clinical work-up revealed the unexpected finding of an underlying pheochromocytoma as well as recent “silent” myocardial infarction. Our case highlights the importance of paying attention to incidental cardiac findings on somatostatin receptor positron emission tomography/computed tomography, as routinely performed in patients with clinically suspected neuroendocrine tumors. These incidental cardiac findings cannot only indicate a primary or secondary (metastatic) neuroendocrine tumor, but also areas of myocardial inflammation, as somatostatin receptors cannot only be found on the majority of neuroendocrine tumors, but also among other tissues on the surface of activated macrophages and lymphocytes. The detection of myocardial inflammation is of clinical importance and its underlying etiology should be evaluated to prompt eventual necessary treatment, as it is a potential driving force for cardiac remodeling and poor prognosis.

Highlights

Incidental imaging findings are a fast growing entity due to the overall rapid rise in demand for advanced medical imaging in combination with the continuously ongoing technical and medical progress, which results in new and potentially better diagnostic abilities
To further determine the underlying etiology of the incidental cardiac finding, a complementary cardiovascular magnetic resonance (CMR) study was performed, which revealed in the same region subendocardial delayed enhancement consistent with an ischemic etiology as well as regional hypokinesia (Figures 3A and C)
The presence of myocardial inflammation on 68Ga-DOTATOC positron emission tomography/computed tomography (PET/CT) and subendocardial delayed enhancement as well as regional wall motion abnormality on CMR suggested that the patient had most likely suffered of a recent ‘‘silent’’ myocardial infarction

Summary

INTRODUCTION

Incidental imaging findings are a fast growing entity due to the overall rapid rise in demand for advanced medical imaging in combination with the continuously ongoing technical and medical progress, which results in new and potentially better diagnostic abilities. Echocardiography showed no signs of infective endocarditis Both thoracic and abdominal computed tomography were performed in search of the origin of the patient’s recurrent fever, which revealed a right-sided adrenal mass with central necrosis as well as a renal cyst (Figure 2A). In the light of these findings, a new thorough medical history revealed that the patient’s recurrent episodes of chest discomfort had even a relation to physical activity and food intake. This made the diagnosis of an underlying coronary artery disease even more likely together with the presence of coronary calcification on the previously performed thoracic computed tomography. Routine histopathologic analysis of the removed adrenal mass revealed a classic appearance of a pheochromocytoma (Figure 5)

Findings

DISCUSSION

CONCLUSION