Breast lipoma

Last revised by Ashesh Ishwarlal Ranchod on 4 Jul 2023

Breast lipomas are benign breast lesions and are classified as BIRADS II lesions.

The term giant breast lipoma has been variably defined as a breast lipoma greater than 5 cm or 10 cm in size 5.

Lipomas are mostly asymptomatic and coincidentally discovered on routine mammography. Patients may present with a painless palpable breast lump which is soft and mobile. In these cases the diagnosis is clinically obvious.

Skin tethering or fixation are not features of lipomas.

Lipomas are benign mesenchymal tumors that are composed of mature adipose tissue

Classically a lipoma appears as a fat composed lesion seen predominantly in the subcutaneous plane; however they can be seen anywhere in the breast. Usually lipomas measure anywhere up to 2 cm in size.

Typically seen as a radiolucent mass with no calcification (in rare situation there may be areas of fat necrosis presenting as calcification). They may have a thin, peripheral, fluid density capsule. Mammographic detection may be easier in a dense breast. In the vast majority of cases lipoma is incidentally seen on routine screening.

May be seen as a rounded lesion that is isoechoic or at times slightly hyperechoic to surrounding fat. Occasionally a lipoma can be hypoechoic 4. Multiple thin echogenic septations may be seen running parallel to the skin surface. The lipoma can be readily distinguished from a hamartoma by the ultrasound and mammogram appearances. Compressibility of the lesion can also be demonstrated on ultrasonography.

These lesions are also found in the male breast.

These lesions are rarely a diagnostic or imaging dilemma. Enlargement of a lipoma is an indication for biopsy. They rarely undergo malignant transformation and are not associated with an increased risk of developing breast cancer.

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Case 1: with concurrent cancer in same breast
    Drag here to reorder.
  • Case 2: mammogram
    Drag here to reorder.
  • Case 2: ultrasound
    Drag here to reorder.
  • Case 3
    Drag here to reorder.
  • Case 4
    Drag here to reorder.
  • Case 5
    Drag here to reorder.
  • Case 6: gigantomastia with breast lipoma
    Drag here to reorder.
  • Case 7
    Drag here to reorder.
  • Case 8
    Drag here to reorder.