A very rare origin of a tumor in the right atrium

Primary cardiac tumors are extremely uncommon but metastases can result from direct invasion from the mediastinum, hematogenous spread or extension of the tumor into the vena cava and the right atrium.

A 37-year-old male with no previous history of chronic diseases was admitted to the hospital due to non-specific chest discomfort, non-productive cough and weakness lasting for several weeks. Physical examination was unremarkable except for tachycardia and bibasal rales. Chest radiogram revealed multiple pulmonary lesions suggesting metastases. A mass in the right adrenal gland was found on abdominal ultrasound and CT scan. In addition, a pathological lesion in the inferior vena cava extending to the right atrium was detected. Echocardiography revealed a pedunculated mass measuring 2.3x1.5 cm, located in the right atrium, which originated from the inferior vena cava. During the diastole, it prolapsed to the right ventricle but did not significantly affect blood flow through the tricuspid valve. Adrenal tumor biopsy revealed adrenocortical cancer and treatment with mitotane was started. After a seizure episode, brain MRI was performed and showed metastases surrounded by edema. Due to the patient's poor general condition and progression of the disease during mitotane treatment was later withdrawn and the patient was referred for the hospice care where he died 2 months later.

Adrenocortical cancer is a rare malignant neoplasm with an estimated annual incidence of 4-12 cases per 1,000,000. It is characterized by a tendency for local invasion and multiple metastases to the lungs, liver and bones. In the literature, there are only a few cases of adrenocortical cancer directly extending from the inferior vena cava to the right atrium.