Primary cardiac osteosarcoma in a young man with severe congestive heart failure.

A primary cardiac malignant tumor is very rare; its prevalence is only 0.002-0.28%. Among most malignant tumors, angiosarcoma, leiomyosarcoma, and mesothelioma occupy the majority. A cardiac osteosarcoma is extremely rare: to our knowledge, only 36 cases have been reported worldwide. We present a 22-year-old case featuring severe congestive heart failure. Hemodynamically the tumor led to significant obstruction of the mitral valve. The patient underwent an emergency resection operation, but multiple metastases occurred. Though the characteristics still remain unclear because of the low prevalence, it is very important that these tumors be distinguished from benign tumors because of early resection operation.