Melanotic schwannoma mimicking myositis ossificans

Pelvic radiographs of a 20-year-old woman showed a bony mass lesion lateral to the left iliac bone. CT and Tc-99m MDP whole-body scanning were also performed for further assessment. All studies strongly suggested a diagnosis of myositis ossificans; however, a pathologic diagnosis of melanotic schwannoma was made after the mass was excised. Cases of melanotic schwannoma have been reported in different anatomic locations, some of which were reported to be a component of the Carney complex. Further diagnostic work-up in this patient revealed no other signs of this complex.