Recurrence of a Thymic Carcinoid Tumour 15 Years After Resection With Multiple Myopericardial Cardiac Metastases: The Role of Multimodality Imaging

A rare case of thymic carcinoid presenting with gastrointestinal symptoms and pericardium effusion

Background

Thymic carcinoid is one of an extremely rare type of malignant neuroendocrine tumor with a poor prognosis. Invasion of thymic carcinoid to other organs could lead to devastating consequences. It has been reported that thymic carcinoid mainly invaded to the pleura, lungs, liver, pancreas and bone, while rarely to the cardiac, especially to the ventricle.

Case presentation

A 53-year-old man presented with gastrointestinal symptoms and persistent pericardial effusion. Multiple imaging tools, including chest computed tomography (CT), magnetic resonance imaging (MRI), 18F-Fluorodeoxyglucose positron emission tomography/CT (18F-FDG PET/CT) showed a malignant neoplasm arising from the thymus invading into the biventricular myocardium, pericardium, and left superior pulmonary veins. The tumor was finally diagnosed as a thymic carcinoid through pathological examination.

Conclusion

This is a rare case of thymic carcinoid invading the ventricular myocardium, which presented as subacute heart failure. The observations in this case would be useful for differential diagnosis of primary heart disease and invasion of heart due to thymic carcinoid.

A concealed carcinoid cardiac metastasis uncovered by comprehensive cardiovascular magnetic resonance-based tissue characterization: a case report

Background

Cardiac metastases of carcinoid tumours are extremely rare, and their diagnosis poses a significant challenge. A variety of techniques has been reported in the literature for this purpose, ranging from echocardiogram to the Indium-111 Octreotide, positron emission tomography using specific tracers, and biopsy. Occasionally, the diagnosis is only made post-mortem. Recently, CMR (cardiovascular magnetic resonance) has been added to the diagnostic toolkit. This case report describes the CMR sequences that can be used to characterize cardiac metastases of carcinoid tumours.

Case summary

A 55-year-old woman with an antecedent history of resected carcinoid tumour of the ileocecal junction underwent whole-body In-111 Octreoscan single-photon emission computed tomography in the context of her follow-up. This raised the suspicion of pericardial involvement, which prompted a CMR study. Comprehensive CMR findings were consistent with isolated carcinoid tumour metastasis embedded within the anterior papillary muscle. We describe the CMR sequences that were used to characterize the metastasis.

Discussion

The rarity of cardiac metastasis of carcinoid tumour makes its diagnosis challenging and warrants a high level of clinical suspicion. Cardiovascular magnetic resonance imaging proves to be an indispensable tool in the tissue characterization of such tumours.

Recommendation of long-term and systemic management according to the risk factors in rectal NETs patients

Rectal neuroendocrine tumors (NETs) are often found as small lesions, which can be treated by endoscopic resection. However, high risk cases with lymph node (LN) metastasis are indication of radical surgery. Furthermore, rectal NETs are often associated with late recurrences and/or multiple cancer development. Therefore, proper surgical indication and patients' management are required. We investigated the clinicopathological features of 79 rectal NET cases in order to elucidate risk factors for synchronous LN metastasis, recurrence, and multiple cancers. Recently, we reported that in pancreatic NET patients, a loss of heterozygosity (LOH) in PHLDA3 was associated with poorer prognosis, and that LOH of both PHLDA3 and MEN1 was frequently observed. Therefore, PHLDA3 and MEN1 LOH were also assessed in rectal NET patients for their association with clinicopathological features. Of the 79 patients, LN metastases were found in 12.7%, recurrences in 3.8%, and multiple cancers in 30.4% of the subjects. PHLDA3 and MEN1 LOH were found in 60.0% and 66.7% of the subjects, respectively. Lymphatic invasion and WHO classification 2010 were found to be independent risks for LN metastasis. There were three cases of recurrence, all of which occurred more than 3 years after resection and two of which exhibited LN metastasis. Older age and LOH in PHLDA3 were associated with the presence of multiple cancers. Long-term and systemic management of patients with rectal NETs is therefore recommended in accordance with these risk factors.