Extraskeletal osteosarcoma of the pleura: a case report

Abstract

We herein present an exceedingly rare case of pleural osteosarcoma that was surgically resected in an elderly patient. A 74-year-old man, complaining of a dry cough and breathlessness on effort, was found to have massive pleural effusion on a chest X-ray. The chest CT and MRI scans indicated a massive effusion and a pleural tumor encasing the left lower lung. The resected tumor was histologically an osteosarcoma, measuring 11.3 x 9.0 x 6.0 cm. Because there was no evidence of any other primary tumor, the diagnosis of extraskeletal osteosarcoma was appropriate.

Extraskeletal Osteosarcoma Arising from the Pleura

“…Extraskeletal osteosarcoma is defined as the malignant tumor originating from the soft tissues without involvement of the bone and composed of malignant cells of an osteoblastic phenotype producing an osseous matrix [2]. It dominantly occurs in middle-aged patients in contrast to osteogenic sarcoma, which commonly occurs in younger patients under the age of 20 years, and the tumor can cause symptoms by its mass effect.…”

“…Approximately half the cases of this tumor occur in the lower extremity, and the other half frequently occur in the upper extremity, retroperitoneum, and the trunk [3]. Extraskeletal osteosarcoma rarely occurs in the pleural cavity, and a majority of these tumors arise from the diaphragm [2]. Furthermore, the tumor originating from the parietal pleura is extremely rare [4].…”

“…However, differential diagnosis of extraskeletal osteosarcoma by a CT scan is generally difficult even though the CT scan can provide precise images, because calcification in the pleural cavity can be produced by other etiologies including benign and malignant diseases [4]. The benign causes include trauma, infection, bleeding, calcifying fibrous pseudotumor, and calcified plaque by asbestos exposure, while the malignant causes include metastasis from osteogenic osteosarcoma, malignant pleural mesothelioma, parosteal osteosarcoma of the rib, and osseous Paget’s disease of the bone [2,4]. Therefore, comprehensive consideration including symptoms, occupational history, and medical history is required for correct diagnosis.…”

Chondroblastic osteosarcoma arising from the pleura: Report of a case

“…To our knowledge, only four cases of pleural osteosarcoma have ever been previously reported. [2][3][4][5] Here we present the case of a 64-yearold Japanese man with extraskeletal chondroblastic osteosarcoma that originally had arisen from the pleura. Both clinical and radiographic evaluations failed to reveal any tumor at other sites.…”

“…[2][3][4][5] All of these cases were male. The onset age of such patients was the sixth to seventh decade of life, in contrast to skeletal osteosarcoma, in which the peak incidence tends to be in the second decade of life.…”