Prominent right ventricular mass in a young patient with a history of classic testicular seminoma: a case report

BACKGROUND: The incidence of intracardiac masses is generally low. In most cases, the formation of a thrombus represents the principal diagnosis in clinical practice. The differential diagnosis mainly includes primary tumours of the heart as well as intracardiac metastases. Testicular cancer is a rare malignancy, accounting for approximately 1% of all male tumours. Cardiac metastasis of a seminoma is extremely rare. CASE SUMMARY: A 30-year-old man with a history of a classic seminoma of the right testis was referred to our university hospital from an outside clinic. Transthoracic echocardiography showed a large space-occupying mass in the right ventricle (4.0 cm × 4.5 cm × 5.5 cm) attached to the apex and septum. Cardiac magnetic resonance imaging confirmed the finding of a 5.5 cm × 3.5 cm lesion without freely movable appendage or obstruction of the right ventricular outflow tract. Tissue characterization by T1- and T2-weighted black blood imaging revealed a signal behaviour comparable to pulmonary metastases. Additionally, positron emission tomography (PET) with 250 MBq induced 18-fluorodeoxyglucose ((18)F-FDG) as part of a re-staging showed significant FDG-uptake. Thus, the final diagnosis of an intracardiac metastasis of the testicular seminoma was made, and the patient was treated with cisplatin, etoposide, and bleomycin chemotherapy according to the current guidelines. A repeat trans-thoracic echocardiogram (TTE) performed 2 weeks later already demonstrated a significant reduction of the metastasis with a diameter of 3.3 cm × 3.0 cm. DISCUSSION: In the past few years, multimodality imaging has become essential in the diagnostic evaluation of cardiac disease. In order to improve the diagnostic accuracy, a modern approach should preferably contain the integration of different imaging modalities. Cardiac magnetic resonance imaging as well as (18)F-FDG-PET/computed tomography helped us reach the aetiological diagnosis of an intracardiac metastasis and to initiate prompt treatment.