Cardiac metastasis from a squamous cell carcinoma of the tongue in the absence of local recurrence.

Editor,

A 77-year-old man presented to hospital following two episodes of collapse. Past medical history was significant for stable angina, osteoarthritis and squamous cell carcinoma of the tongue. On examination, he appeared frail with evidence of weight loss. Pulse was recorded at 108 beats per minute and was irregular. He was pyrexial with a temperature of 38.3°C. Auscultation of the chest revealed crackles at the left base. The remainder of the physical examination was unremarkable. In particular there was no evidence of lymphadenopathy or local recurrence of tongue cancer. An electrocardiogram confirmed atrial fibrillation. A chest X-ray displayed widespread pleural plaques and consolidation at the left base. Blood work was significant for an elevated white cell count, serum high sensitivity troponin T concentration and serum C-reactive protein concentration.

The patient was commenced on digoxin and received treatment for a lower respiratory tract infection. A computed tomography (CT) scan of brain was unremarkable. A transthoracic echocardiogram demonstrated a large mass in the right atrium. There was no evidence of a pericardial effusion. A trans-oesophageal echocardiogram confirmed a large mobile mass in the right atrium, prolapsing through the tricuspid valve during the cardiac cycle, with evidence of intramural invasion (Figure 1). A cardiovascular magnetic resonance imaging scan revealed a large infiltrative mass within the mediastinum extending from the distal superior vena cava to the diaphragmatic surface of the right ventricle (Figure 2). The appearances were felt to be in keeping with invasive malignancy. No definite evidence of lymph node or metastatic disease was observed on a CT scan of chest. The patient’s condition deteriorated acutely on day 28 of he admission; he was managed conservatively and died the following day. On post-mortem examination, a tumour was observed arising from the medial border of the right atrium, extending through the tricuspid valve and into the right ventricle with infiltration of the myocardium (Figure 3). Histology demonstrated squamous cell carcinoma infiltrating the myocardium. The histological appearances were similar to those of the patient’s previous tongue tumour (Figure 4), confirming a diagnosis of a cardiac metastasis from a squamous cell carcinoma of the tongue.

Fig 1

Trans-oesophageal echocardiogram images demonstrating a large mass (M) arising in the right atrium (RA) and prolapsing through the tricuspid valve (TV) into the right ventricle (RV), during the cardiac cycle, with evidence of intramural invasion (I).

Fig 2

Cardiac magnetic resonance image demonstrating a large mass (M) involving the free surface of the right atrium (RA), right ventricle (RV) and tricuspid valve (TV).

Fig 3

Postmortem appearance of the heart demonstrating a tear (*) within the right aorta.

Fig 4

Histology slides demonstrating metastatic squamous cell carcinoma infiltrating the myocardium (left) and primary squamous cell carcinoma of the tongue (right). Similarities between the primary tumour and a metastasis arising from it can be appreciated, in particular, the eosinophilic whorls of squamous cells (asterisks).

Post-mortem studies show cardiac metastases in up to 25% of patients who have died from malignancy, however, ante-mortem presentation is rare. The most common tumours metastasising to the heart are carcinomas of the lung, breast and oesophagus, malignant lymphoma, leukaemia and malignant melanoma[1]. Cardiac metastases usually present in patients with advanced widespread tumour disease[2]. Treatment is therefore usually palliative and the prognosis is poor[1]. In the present case an extensive cardiac metastasis was observed in the absence of clinically detectable local recurrence, lymphadenopathy or metastases elsewhere. Although such cases of cardiac metastasis are uncommon, similar cases have been described in the literature[3]. This diagnosis should therefore be considered in patients with a history of malignancy and new cardiovascular symptoms of uncertain aetiology.