Large right ventricle cardiac leiomyoma metastasis from uterine leiomyoma

© BMJ Publishing Group Limited 2022. No commercial reuse. See rights and permissions. Published by BMJ. DESCRIPTION Most cardiac tumours arise secondary to metastatic neoplasms. Smooth muscle tumours of the heart are rare. Here, we present the case of a large benign leiomyoma that metastasised from the uterus to the heart. A woman in her 40s was admitted to our medical centre with a cough, shortness of breath and abdominal pain. She had a history of uterine leiomyoma and underwent exploratory laparotomy and hysterectomy 10 years ago. Histopathological examination at the time revealed that the uterus contained multiple benign leiomyomata; necrosis, atypia or increased mitotic activity. During her current admission, physical examination revealed a systolic murmur of grade 4/6; an abnormal ‘plop’ sound was also audible at the left sternal border, in the fourth intercostal space. Transthoracic echocardiography revealed a huge rodlike tumour located in the right ventricle (figure 1A) and extending into the right ventricular outflow tract. The abnormal sound was related to the movement of the tumour. We suspected that the patient’s cough was caused by the tumour as it was stuck in the right ventricle outflow. Enhanced CT scan results corroborated echocardiography findings as well as revealing multiple small bilateral pulmonary nodules (figure 1B–D). Emergency cardiac surgery was performed via median sternotomy. After the right ventricular outflow incision was made, a mobile white dense tumour, measuring 97 × 32 × 20 mm, was found (figure 2A,B). The tumour was attached to the posterior wall of the right ventricle by a narrow stalk. A small spherical white nodule was also noted to be attached to the chordae, towards the anterior leaflet of the tricuspid valve. The nodule measured 20 × 5 × 3 mm. After the surgery, the patient recovered well. She was discharged home 8 days after the operation. Histological examination of the resected tumour revealed that it was composed of spindlelike cells, and interstitial collagen, resembling benign leiomyoma. This suggested a uterine origin as the cardiac leiomyoma was similar to her previous uterine leiomyoma. Very low levels of atypia and mitoses were discovered. Margins of resection were microscopically negative for tumour cells. Immunohistochemical staining for α-smooth muscle actin, desmin, and progesterone and oestrogen receptors was positive. Staining for CD34 was negative. At followup after cardiac surgery, there is no cardiac recurrence and no evidence of metastatic