Chest Wall Fat Mimicking Tumor

Fig.2: Axial CT shows an extrapleural fat (arrowheads) deep to the costal margin.

Facts
- Extrapleural costal fat can be mistaken for pleural lesions including plaque and tumor
- Thickening of the extrapleural costal fat can be associated with lung scarring
- CT is an easy tool to use differentiate between fat and soft tissue mass
- Fat can be drawn into fissures (as seen on Fig.1). It looks as if it is in the pleural space, but it is covered by parietal pleura - therefore is extrapleural

Case courtesy of RadiologyinThai.com