An expansile, mildly lobulated, septated lesion is seen within the humeral diaphysis. The lesion shows low-to-intermediate T1 and high T2/STIR signal intensity with a T1/T2 hypointense sclerotic rim. The lesion measures 11 x 3 x 3 cm in its main CC, TS and AP axes, respectively. There is endosteal scalloping with a sclerotic margin and a narrow zone of transition. Focal cortical destruction is noted with a small extraosseous soft tissue component at the anterolateral aspect of the lesion. No fluid/fluid levels are seen. The lesion shows heterogeneous post-contrast enhancement, with enhancing septa.