Number 10-01: Myofibroblastic tumor of the right atrium in a 2-year old boy
Case from:Michael D Seckeler, MDa*, Christopher Clarke, MDa, James Gangemi, MDb, Robin D LeGalloc, Andrew Hoyer, MDa
aDepartment of Pediatrics, bDepartment of Surgery, cDepartment of Pathology, University of Virginia, Charlottesville, Virginia, US.
Clinical history: A 2 year-old male with a history of one week febrile illness and cough was evaluated by his pediatrician and diagnosed with bronchitis and provided supportive treatment. However, the patient developed new respiratory distress.
A chest x-ray showed marked cardiomegaly and an echocardiogram revealed a large pericardial effusion (Movies1-3) with evidence of cardiac tamponade.
Movie 1 Movie 2 Movie 3
After urgent pericardiocentesis, a suspicious mass was noted in the right atrium on a repeat echocardiogram (Movie 4).
Cardiac magnetic resonance (CMR) imaging was performed to further evaluate the characteristics of the mass (Movies 5+6) and a rest 1st pass perfusion was performed (Movie 7).
CMR tissue characterization: In the TSE T1 images the mass appeared hyperintense (Figure 1). The mass remained hyperintense also when a fat saturation pulse was added, confirming that its nature was not lipomatous (Figure 2).
In addition, the pericardium appeared abnormally thicked.
The LGE images suggested that the mass had a fibrotic component (Figures 3 and 4).
Based on the CMR findings, the patient went to surgery for an open biopsy.
On gross examination, there was markedly abnormal pericardium with gelatinous material in the pericardial space. Because of concern for a malignant tumor, the mass was resected.
On microscopic examination, the mass was found to be an inflammatory myofibroblastic tumor. The tumor shows a spindled cell population with a mixed inflammatory infiltrate with areas rich in plasma cells (Figure 5). The spindle cells have a stellate shape with large, hyperchromatic nuclei with coarse chromatin and prominent nucleoli (Figure 6).
The patient recovered well from surgery and was discharged home.
Perspective: Cardiac tumors in children are quite rare, and the most common are rhabdomyomas. Myofibroblastic tumors are rare and usually occur in children, most commonly in the lungs or gastrointestinal tract. Fewer than 20 cases of primary cardiac myofibroblastic tumors have been described in the literature (ref 1). While generally benign, they can cause symptoms if they become obstructive. In general, treatment is complete excision, and up to 25% may recur (ref 2). While CMR images have been reported in an adult with myofibroblastic tumor, this is the first case to present CMR images of a myofibroblastic tumor (ref 3) of the heart in a child. This case illustrates how CMR may be used to better define the extent and composition of intracardiac tumors and aid in the decision for surgical resection, even in children.
1. Adler A, Fimbres A, Marcinak J, Johnson A, Zheng X, Hasegawa S, Shulman ST. Inflammatory pseudotumor of the heart caused by Listeria monocytogenes infection. J Infect. 2009;58:161-3.
2. Anvari MS, Soleimani A, Abbasi A, Boroumand MA, Marzban M, Karimi AA, Yazdanifard P, Shirani S, Sahebjam M. Inflammatory myofibroblastic tumor of the right ventricle causing tricuspid valve regurgitation. Tex Heart Inst J. 2009;36:164-7.