MRI Case 5

61 y/o F presents for screening MRI. What is the incidental extramammary finding shown?


  • Lipomas can be found in the skin, breast tissue, muscles, and even osseous structures.
  • Deep chest wall lipomas can appear infiltrative, rather than encapsulated (as seen here).
  • Appreciate the predominantly fatty contents of the tumor on all imaging.
  • When there is lesion complexity, tissue sampling may be required to rule out well-differentiated liposarcoma.
  • Imaging findings which may suggest malignancy include size > 10 cm and thick nodular septae.
    • MRI can be obtained to assess for enhancement of the septae.

Related Radiology Article: Gao Y, Ibidapo O, Toth HK, Moy L. Delineating extramammary findings at breast MR imaging. Radiographics. 2017 Jan;37(1):10-31.