Low-grade fibromyxoid sarcoma: an unusual cardiac location.

We report the unusual cardiac localization of a primary low-grade fibromyxoid sarcoma of the right ventricle in a 57-year-old woman. Histological examination revealed a prevalent myxoid appearance with whorling growth pattern of small or spindle cells with bland features alternating with rare more collagenous hypocellular areas with rare atypical cells. Genomic polymerase chain reaction of genomic DNA revealed the typical FUS/Creb3L2 fusion gene products typical of low-grade fibromyxoid sarcoma. The tumor was surgically removed and recurred after 7 years as high-grade pleomorphic sarcoma. The patient died 6 months after the clinical manifestation of recurrence. Low-grade fibromyxoid sarcoma of soft tissues is a rare, distinctive variant of fibrosarcoma-typically arising in deep soft tissue of lower extremities and trunk-that rarely metastasizes. Clinically, low-grade fibromyxoid sarcoma is characterized by a longer survival rate compared to other sarcomas, suggesting its consideration in the differential diagnosis of cardiac tumors with a myxoid appearance.