Discussion
Primary malignant tumors of the heart are extremely rare, constituting around 10% of cardiac tumors in children. Sarcomas are the most common primary cardiac malignant tumors (95%) followed by lymphomas [1].Angiosarcoma, rhabdomyosarcoma and undifferentiated sarcomas are the most common sarcomas in children in the order of frequency of occurrence [2].
Rhabdomyosarcomas are mesenchymal tumors originating from undifferentiated striated muscle [1]. They are more common in males [3] and show extensive and aggressive local tissue infiltration and vessel extension [4]. Most lesions tend to be single and occur more frequently in the left atrium but, they can involve any cardiac chamber. Histologically, they are classified as embryonal, alveolar, pleomorphic and other types while embryonal variety (75%) is the most common type in pediatric population [5].Most cases of rhabdomyosarcomas are sporadic in nature although association with familial syndromes like LiFraumeni and Neurofibromatosis type I is not uncommon [6].They usually present with signs and symptoms congestive heart failure, chest pain, outflow tract obstruction, recurrent pericardial effusions, arrhythmias, pulmonary emboli and rarely sudden death depending upon the size and location of the tumor. Echocardiography or Computing Tomography/MRI of the heart helps with establishing the diagnosis. Open surgical or endomyocardial biopsy aids the histological diagnosis of the tumor. A thorough search with CT/MRI must be made to ascertain the metastatic spread of the lesion. Palliative debulking surgery, chemotherapy and radiotherapy extend survival but prognosis is extremely poor with short survival (upto 13 months) due to local infiltration and metastasis [7]