Imaging features of atypical thoracic Castleman disease.

The imaging features of 16 cases of pathologically proven atypical thoracic Castleman disease (CD) were retrospectively reviewed. Thirteen out of 16 tumors originated from atypical locations, including eight from the pleura and one each from the axilla, supraclavicular fossa, intercostal space, pericardium, and lung. Six out of 16 tumors revealed atypical enhancement, including poor CT enhancement in three tumors, target-like CT enhancement in two tumors, and concentric MR enhancement pattern in one tumor. These atypical enhancement patterns were histopathologically corresponded to various degrees of degeneration, necrosis, and fibrosis.