Intraparenchymal pulmonary lipoma: pathologic-radiologic correlation of a rare presentation of a common neoplasm

We report a rare case of pulmonary intraparenchymal lipoma. Lipomas are benign adipocytic tumors, which are ubiquitous in distribution, particularly in the subcutis and soft tissue. Visceral lipomas, in particular, pulmonary lipomas, are rarely reported. Even rarer are intraparenchymal lipomas, such as this case, of which less than 10 have been reported in the medical literature. The radiologic (computed tomographic scan) findings of pulmonary lipoma may be somewhat difficult to evaluate. In this case, on initial review, the computed tomographic findings were not diagnostic, but retrospective analysis revealed attenuation values suggestive of an adipocytic lesion. A high index of suspicion and careful attention to attenuation values are therefore required for radiologic diagnosis. Excision is necessary for histologic confirmation, which is generally relatively straight forward, although admixture with fibrous tissue and some cytologic atypia may pose diagnostic challenges.