Intrapericardial carcinoid metastasis

CASE REPORTS

Intrapericardial Carcinoid Metastasis Nicholas Collins, B Med, Greg Bellamy, MBBS, FRACP, and Peter Hayes, MBBS, FRACP, Newcastle, Australia

Carcinoid tumors are malignancies of neuroendocrine tissue. Metastasis, most commonly to the liver, is associated with the carcinoid syndrome characterized by secretory symptoms and right-sided valvular heart disease. We report a case of previously unidentified pericardial metastasis, in the absence of any valvular disease, thus, reflecting an unusual cardiac complication of this tumor. A 50-year-old patient with histologically confirmed carcinoid syndrome underwent screening transthoracic echocardiography that demonstrated a large mass posterior to the interatrial septum. The location of this mass

CASE REPORT Carcinoid tumors are an uncommon malignancy of neuroendocrine tissue. Hepatic metastasis, and the associated carcinoid syndrome, can produce typical right-sided valvular heart disease. Most commonly this is in the form of tricuspid valve stenosis and regurgitation.1 We report an unusual case of previously undescribed pericardial metastasis in the absence of associated valvular abnormalities. The symptoms attributable to carcinoid syndrome in this 50-year-old patient began in 1993. He experienced intermittent secretory symptoms characterized by flushing and diarrhea. Formal diagnosis followed a bowel obstruction in 1997 with carcinoid malignancy confirmed on histology of a periappendiceal mass. Urinary 5-hydroxyindoleacetic acid (HIAA) levels were elevated at the time of diagnosis. Regular somatostatin therapy was started in 1999 for symptom control. He continued to be symptomatic with persistent elevation of his urinary 5-HIAA levels and remained on regular somatostatin therapy. Despite features of the carcinoid syndrome, he had not been previously assessed for cardiac manifestations of the disease and no hepatic metastasis had been documented on liver ultrasonography. In July 2002, the patient underwent screening transthoracic echocardiography to determine the presence of valvular heart disease. He was asymptomatic and results of the physical examination were normal. From John Hunter Hospital. Reprint requests: Nicholas Collins, B Med, Cardiovascular Unit, John Hunter Hospital, New Lambton, NSW 2305, Australia. 0894-7317/$30.00 Copyright 2004 by the American Society of Echocardiography. doi:10.1016/j.echo.2004.02.008

was confirmed by transesophageal echocardiography and magnetic resonance imaging to be entirely within the pericardial space without evidence of myocardial involvement. The mass was removed at thoracotomy and histology confirmed metastatic carcinoid disease. Although patients with carcinoid syndrome are at risk of cardiac valvular complications, and should be screened, this case demonstrates an unusual and previously unidentified site of metastatic disease. (J Am Soc Echocardiogr 2004; 17:675-6.)

Transthoracic echocardiography demonstrated a 33- ⫻ 37-mm mass posterior to the interatrial groove, along the superior aspect of the atria. There was no associated valvular abnormality. Transesophageal echocardiography was performed to further evaluate this mass (Figure 1). Transesophageal echocardiography revealed a well-circumscribed, echodense, heterogenous mass posterior to the right atrium within the interatrial groove, measuring 37 ⫻ 29 mm (in transverse dimensions) and 54 ⫻ 42 mm (longitudinal). There was mild right atrial compression with surrounding fluid suggesting a pericardial origin of the mass. Magnetic resonance imaging demonstrated 2 distinct pericardial masses, one within the posterior interatrial groove, and the other within the pericardial fat pad, posterior and lateral to the left ventricle. There was no evidence of myocardial infiltration. Figures 2 and 3 demonstrate a mass posterior to the right atrium contained within the pericardial space, adjacent to the right main bronchus. Thoracotomy was performed with incomplete removal of the larger mass. Histopathology demonstrated carcinoid tumor. Operation confirmed the pericardial nature of the metastasis, without associated myocardial infiltration. The patient remained symptomatic with persistent elevation of urinary 5-HIAA levels.

DISCUSSION The carcinoid syndrome is characterized most commonly by flushing and diarrhea. Other features include wheezing, valvular dysfunction, and pellagra. These symptoms are the result of release by the tumor of 5-hydroxytryptamine metabolites and other vasoactive mediators. Most patients will have

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Figure 1 Transesophageal echocardiography demonstrates a heterogenous mass posterior to the interatrial septum, adjacent to the right atrium.

Figure 3 Axial magnetic resonance image outlining mass adjacent to right main bronchus.

most common valvular abnormality, with left-sided disease occurring in less than 10%.1,3 In one previous review undertaken by Pellikka et al,1 56% of patients with carcinoid syndrome demonstrated cardiac carcinoid at echocardiography. In this series, there were no documented pericardial metastases. According to Modlin and Sandlor,4 lymph nodes, liver, lung, and peritoneum are the most frequent sites of metastatic disease. Patients with carcinoid syndrome are at high risk for cardiac complications and appropriate screening is necessary to identify characteristic valvular abnormalities. Although myocardial metastasis has been identified, previous reviews have not identified pericardial metastasis complicating carcinoid tumors. This case represents an unusual and previously unrecognized site of carcinoid metastatic disease. Figure 2 T2-weighted sagittal image demonstrating a mass of intermediate signal intensity posterior to the right atrium (arrow).

REFERENCES

metastatic disease in association with the carcinoid syndrome.2 Carcinoid heart disease occurs in up to two thirds of patients with the carcinoid syndrome. The characteristic manifestations are of plaquelike, fibrous deposits on the tricuspid and pulmonary valves. Serum and urinary 5-HIAA levels are higher among those with carcinoid heart disease complicating carcinoid syndrome.3 Tricuspid regurgitation is the

1. Pellikka PA, Tajic AJ, Khandheria BK, Seward JB, Callahan JA, Pitot HC, et al. Carcinoid heart disease: clinical and echocardiographic spectrum in 74 patients. Circulation 1993;87:118896. 2. Caplin ME, Buscombe JR, Hilson AJ, Jones AL, Watkinson AF, Burroughs AK. Carcinoid tumour. Lancet 1998;352:799803. 3. Kulke MH, Mayer RJ. Carcinoid tumors. N Engl J Med 1999; 340:858-68. 4. Modlin IM, Sandlor A. An analysis of 8305 cases of carcinoid tumors. Cancer 1997;79:813-29.