Osteosarcoma Metastases With Direct Cardiac Invasion: A Case Report and Review of the Pediatric Literature

Metastatic osteosarcoma with direct cardiac involvement is an exceptionally rare finding, with only 63 total reported cases in the English literature over the past 123 years. Although the precise incidence is unknown, we estimate that direct cardiac involvement currently occurs in <2% of metastatic osteosarcoma cases. We also find that before the adoption of adjuvant chemotherapy as a standard of care therapy for osteosarcoma, metastatic osteosarcoma to the heart was much more common than it is today, as cardiac involvement occurred in ∼20% of cases of metastatic osteosarcoma before the 1980s. This suggests that adjuvant chemotherapy has not only improved the overall prognosis of osteosarcoma, but also altered the metastatic pattern of disease. In this paper we present the case of an 11-year-old boy with metastatic osteosarcoma to the cardiac interventricular septum, as well as review 20 other previously reported pediatric cases of metastatic osteosarcoma to the heart. We also analyzed the cardiac surgical outcomes for 11 pediatric patients with metastatic osteosarcoma to the heart. The median disease-free survival time was 12 months, demonstrating that metastatic osteosarcoma to the heart is currently a rare occurrence with a poor prognosis.

Ewing Sarcoma in the Right Ventricle

Ewing sarcoma is the second most prevalent malignant primary bone tumor but constitutes only a small proportion of cardiac metastases. We present a case of asymptomatic Ewing sarcoma metastatic to the right ventricle. A 36-year-old man presented for evaluation and resection of a pedunculated right ventricular cardiac tumor. Three years before, he had been diagnosed with translocation-negative Ewing sarcoma, for which he had undergone chemotherapy and amputation of the left leg below the knee. We resected the right ventricular tumor. Analysis of the resected mass supported the diagnosis of metastatic Ewing sarcoma. Postoperative transthoracic echocardiograms showed normal biventricular size and function. One year later, the patient had no recurrence of the sarcoma. In addition to discussing this case, we review the relevant medical literature.