Subcutaneous benign fibrous histiocytoma of the cheek. Case report and review of the literature.

Fibrous histiocytoma is a benign tumour composed of a mixture of fibroblastic and histiocytic cells. Based on the location of this tumour, fibrous histiocytoma are usually divided into cutaneous types and those involving deep tissues. These lesions most often arise on the skin, but may rarely occur in soft deep tissues. The diagnosis of fibrous histiocytoma may be clinically difficult when the lesion is located in the deep tissues, and is frequently confirmed after local excision. The most important diagnostic distinction is the separation of this tumour from aggressive forms of fibrohistiocytic neoplasms, including dermatofibrosarcoma protuberans and malignant fibrous histiocytoma. A 19-year-old male presented with a painless swelling on the right cheek. Detailed clinical and laboratory examinations were performed. The lesion had been totally excised under local anaesthesia, and histopathology revealed a benign fibrous histiocytoma. The diagnosis, location, treatment and prognosis of fibrous histiocytoma are also discussed.

Pulmonary tumor embolism from primary cardiac B-cell lymphoma.

We report the case of a 54-year-old man with pulmonary embolism during convalescence from "idiopathic" pericarditis. A transthoracic echocardiographic examination indicated a large mass within the right atrium. Subsequently, he died from refractory hypotension. On autopsy, two large whitish nodules were found in the right atrium; there was also nodular epicardial infiltration. Both lungs showed multiple, grossly visible tumor emboli with pulmonary infarction and no evidence of conventional thromboembolism. This is the first report of pulmonary tumor embolism due to large cell B-cell primary cardiac lymphoma. Refractory unexplained pericardial effusion, pulmonary embolism without risk factors for venous thrombosis, and/or the existence of a mass in the right heart should arouse clinical suspicion for this rare malignancy.

Crescentic and ring-shaped opacities. CT features in two cases of bronchiolitis obliterans organizing pneumonia (BOOP).

Two cases of idiopathic bronchiolitis obliterans organizing pneumonia (BOOP) with unusual CT findings are presented. On CT both cases exhibited crescentic and ring-shaped opacities, surrounding areas of groundglass attenuation, and associated with a nodular pattern in one patient and airspace consolidations in the second patient. CT-pathologic correlation disclosed that the central areas of groundglass attenuation corresponded to alveolar septal inflammation, in contrast to the denser periphery where granulomatous tissue in peripheral airspaces predominated. In the broad spectrum of CT findings, BOOP can exhibit specific CT features with regard to the crescentic or ring-shaped opacities with a central groundglass attenuation area. Since these features have not been described in any other disease, they might be characteristic features for the diagnosis of BOOP.