Ostéosarcome extrasquelettique avec localisations multiples pulmonaire, intracardiaque et cutanée révélé par une tumeur occipitale

A 53-year-old women, from Morocco, presented with a 2-month history of dyspnea, associated with a 4 kg weight loss without fever. A right-sided occipital enlarging tumour was then discovered, known since one year by the patient. There was a suspect right-sided jugular lymphnode, measuring 1.5 cm. Chest radiography revealed a voluminous left-sided pleural effusion. Histological examination of a cutaneous biopsy of the scalp showed a tumoral proliferation located in the reticular dermis, well circumscribed, edged with lobules of a sarcomatous cell proliferation generating osteoid tissue, and tumoral bone in a centripetal way, and cartilage, without any detectable carcinomatous cell population with immunocytochemistrical techniques. Cerebral MRI confirmed the existence of a right-sided occipital mass invading the scalp but respecting the outer table of bones of skull. Computed tomography (CT) of the chest showed the left-sided pleural effusion and a voluminous and heterogeneous tumoral mass in the left lung which contained necrosis and calcifications with an intracardiac extension explored more precisely by cardiac MRI and trans-esophageal echocardiography. The diagnosis of primary soft-tissue osteosarcoma was retained. Lesions were stabilized after intraveinous adriamycin-cisplatin courses of chemotherapy.