Pedunculated subpleural lipoma with incomplete torsion: A case report

Lipoma is a common benign neoplasm, but lipoma arising from the pleura is rare. Most pleural lipomas are asymptomatic and are discovered incidentally on chest radiographs. Here we report an unusual case of a pedunculated subpleural lipoma with incomplete torsion in a 29-year-old woman who presented with flank pain. On chest radiography, there was a well-defined, ellipsoidal, homogeneous, radioopaque mass in the left lower lobe. An intrathoracic tumor was suspected, and video-assisted thoracic surgery was performed to establish the final diagnosis. The resected tumor was a 10×5 cm sized pedunculated pleural mass. The cut surface showed a yellow, well-circumscribed mass with areas of hemorrhage. Histologically, the tumor was composed of mature adipose tissue with fibrous septae composed of fibroblasts. The outer surface of the tumor was covered by mesothelial cells. Some areas were hypercellular, and occasional mitoses were found, but neither lipoblasts nor atypical mitoses were identified. (Korean J Med 74:676-679, 2008)