A rare presentation of a solitary fibrous tumour

A 67-year-old woman was referred to our centre because of an intracardiac mass. Her medical history included a retroperitoneal tumour (2015), lung metastases (2020) and bilateral breast implantation. Transthoracic echocardiography had a poor acoustic window due to the breast implants. Transoesophageal echocardiography showed a mass in the left atrium (6.2 × 4.4 cm) that occluded most of the atrium, had an uneven shape and showed heterogeneous echogenicity. Due to its size, the mass, which seemed to derive from the left pulmonary vein, restricted transmitral flow; mean transmitral gradient was 7 mm Hg (Fig. 1a, b, and see Videos 1 and 2 in Electronic Supplementary Material). Cardiac computed tomography (CT) angiography showed a vascularised cardiac mass with reduced mobility and uneven contrast enhancement; there was no cardiac infiltration. CT showed the tumour entered the heart from the left upper pulmonary vein and revealed left superior pulmonary vein thrombosis (Fig. 1c, d, and see Videos 3–5 in Electronic Supplementary Material); lung window study indicated several lung metastases (Fig. 1e). Transthoracic biopsy of one metastasis and subsequent pathological examination revealed a solitary fibrous tumour (Fig. 1f). Despite chemotherapy, the patient died. This report is an example of a slow-growing, solitary fibrous tumour turning malignant [1, 2].