Squamous Cell Metastasis from the Tongue to the Myocardium Presenting as Pericardial Effusion

Metastatic cancer of the heart is a rare occurrence. Although most cancer has been documented to metastasize to the heart, the otolaryngology literature contains little mention of this. The reason may be that cardiac metastasis is notoriously difficult to diagnose antemortem. This article presents a case in which metastatic squamous cell carcinoma from the oral cavity to the right ventricular myocardium presented as a pericardial effusion. This was diagnosed with echocardiography and angiography-guided biopsy. The advent of these imaging techniques has greatly facilitated the antemortem diagnosis of cardiac metastasis.1. A 57-year-old man with a long history of tobacco and alcohol abuse had a T1N0M0 squamous cell carcinoma of the right base of the tongue at presentation. Local excision was performed on this lesion in August 1995. The patient received postoperative radiation therapy to the primary site and both sides of the neck. In November of 1995 the patient was admitted to his local hospital with chest pain and mild ST elevation in leads V4 and V5. He was admitted to rule out a myocardial infarction. A cardiac catheterization was performed but was unremarkable. Myocardial infarction was ruled out by enzyme testing; however, his electrocardiogram changes did not resolve. A thallium stress test was performed the following week, and results were essentially normal. Two months later the patient returned with the chief symptom of significant lower extremity edema. On physical examination he had 3+ bilateral lower extremity edema. His laboratory values at that time included a creatinine value of 3.9 mg/dl, a blood urea nitrogen level of 49 mg/dl, and a prothrombin time of 14.8 seconds. His electrocardiogram on admission revealed atrial fibrillation with 2 to 5 mm ST elevation in leads V2 to V6 and Q waves in leads V2 and III. A chest x-ray film showed an enlarged cardiac silhouette and a right lower lobe opacity. A subsequently performed echocardiogram revealed a pericardial effusion. This effusion was tapped and revealed no malignant cells. The echocardiogram was repeated 5 days later and revealed a right ventricular mass. A cardiac MRI study confirmed the presence of a 1.2 cm mass in the right ventricle (Fig. 1). The patient underwent a myocardial biopsy of the mass under fluoroscopic guidance, which showed moderately differentiated squamous cell carcinoma matching the histology of the mass previously excised from the tongue base. A chest CT study was performed, which showed extensive perihilar lymphadenopathy. The patient was not a candidate for a surgical resection of the cardiac metastasis and underwent a course of cisplatin, 5-fluorouracil, bleomycin, and methotrexate. He died several months later of multiorgan system involvement of metastatic squamous cell carcinoma. Cardiac MRI showing 1.2 cm metastatic lesion in the right ventricle (arrow). The first case of metastatic cancer involving the heart was described by Boneti in 1700.2. The diagnosis in this case was made postmortem. Several case series of metastatic cancer to the myocardium were collected throughout the nineteenth century in autopsy surveys. The first antemortem diagnosis was reported in 1913.3. The primary malignancies most commonly metastasizing to the heart are lung cancer, breast cancer, melanoma, and leukemia. Metastatic cancer has been documented to invade the heart by direct extension and hematogenous and lymphatic routes. Since the late nineteenth century, it generally has been accepted that hematogenous spread is the predominant route of invasion.4. Cardiac involvement by metastatic malignancy has been observed almost exclusively in the setting of widespread metastatic disease, especially when metastasis is heavily intrathoracic. It was for this reason that at presentation this patient was not a candidate for cardiac resection. In the most recent autopsy series by Karwinski and Svendsen,5. 5% of 2833 cadavers with malignant neoplasms had cardiac involvement. The reported incidence of cardiac involvement in autopsy series has ranged from 1.5% to 21% of cancer cases collected. Nearly all types of cancers can metastasize to the pericardium, epicardium, or myocardium.5. Head and neck cancer metastasis to the heart is a rare occurrence. Primary tumors of the tongue seem to be encountered most frequently, as documented by DeLoach and Haynes6. in 1953. DeLoach and Haynes discovered that one of nine patients with tongue primary malignancies who were autopsied had myocardial or pericardial involvement. Gassman et al.7. in 1955 reviewed 4124 autopsies of cancer patients in a Veterans Affairs hospital. Of these, 126 had tongue primary tumors. Two (1.5%) of the patients with tongue primary tumors had myocardial or pericardial involvement. Finally, Mnojlovic,8. in a series of 477 autopsies of patients with cancer, found 38 cancers, 9 (24%) of which metastasized to the heart. The wide variability in the incidence most likely reflects a difference in the initial stage of these cancers or their treatment regimen. These variables were not accounted for in these studies. It is clear, however, that in all of these autopsy series squamous cell carcinoma of the tongue does metastasize to the heart with some degree of frequency. To the best of our knowledge, only one case of squamous cell carcinoma of the tongue with metastasis to the heart, diagnosed antemortem, has been reported.9. This patient had decubitus angina 11 months after hemiglossectomy and radiation therapy for a T2N0M0 squamous cell carcinoma of the base of the tongue. The patient had ST depression and inverted T waves anteriorly on electrocardiogram. As with our patient, an echocardiogram revealed a ventricular mass. The signs and symptoms of cardiac metastasis are nonspecific. Our patient had lower extremity edema, pericardial effusion, and electrocardiogram changes at presentation. Atrial fibrillation was present possibly because of atrial dilatation from right ventricular compromise. The patient had hepatic dysfunction and lower extremity edema caused by right ventricular outflow obstruction. The creatinine value and the prothrombin time were elevated. It has been suggested that a prolonged ST segment without evidence of Q waves is pathognomonic of tumor invasion of the myocardium.10. Although our patient had ST elevation, interestingly, Q waves were also present. Electrocardiogram findings may be inconclusive. Fortunately, modern imaging now provides a much more accurate tool for diagnosis. Treatment of cardiac metastasis, however, is generally ineffective. Attempts at resection have been unsuccessful.9., 11. Radiation therapy is useful as a palliative measure, particularly in cases of malignant pericardial effusion.12. Our patient did not have a persistent pericardial effusion and was treated with chemotherapy for palliation. Cardiac metastasis from head and neck cancer is rarely encountered. We present a base-of-tongue squamous cell carcinoma with metastasis to the heart that was diagnosed ante-mortem. Autopsy series indicate that tongue cancer may metastasize more frequently to the heart than from other head and neck sites. However, none of these studies was controlled. Most importantly, cardiac metastasis should be suspected in any patient with cancer in whom new cardiac symptoms develop. The diagnosis is best confirmed with two-dimensional echocardiography or cardiac MRI. A myocardial or endocardial biopsy specimen can be obtained with angiographic guidance. Despite the improvement in diagnostic capability, available treatments are only palliative. All patients eventually die of their metastatic disease.