Hamartom der Mamma

Mimickers of
breast malignancy: imaging findings, pathologic concordance and clinical management. Hamartoma. A 14-year-old presented with unilateral breast enlargement. A mass was not palpable on examination. Color Doppler (a) and longitudinal panoramic ultrasound grayscale images (b) show a hypervascular, 17-cm isoechoic breast mass replacing the entire breast. T1-weighted non-fat-suppressed (c) and T1-weighted fat-suppressed (d) post-contrast MRI images show a well-circumscribed, heterogeneously enhancing breast mass suspicious for a sarcoma (arrow). T2-weighted sagittal images (e) show moderate T2 signal with marked heterogeneity (arrow). Pathology at the time of surgical excision showed hamartoma with areas of pseudoangiomatous stromal hyperplasia and fibroadenomatoid change
insightsimaging.springeropen.com • CC-by-4.0
Hamartoma in
breast with ultrasound
Wikipedia • CC BY-SA 4.0
Radiopaedia • CC-by-nc-sa 3.0 • de

Breast hamartomas, also known as fibroadenolipomas, are benign breast lesions. They are typified by a "breast within a breast" appearance on mammogram.

Epidemiology

They typically occur in women older than 35 years of age.

Clinical presentation

Breast hamartomas most commonly are asymptomatic or present as a painless soft breast lump. They may also present as unilateral breast enlargement without a palpable localized mass .

Pathology

Hamartomas represent benign proliferation of fibrous, glandular, and fatty tissue (hence fibro-adeno-lipoma) surrounded by a thin capsule of connective tissue. All components are found in normal breast tissue, which is why the lesions are considered hamartomatous.

Macroscopically, hamartomas are slightly larger and softer than common adenofibromas and are well-defined, whitish, pinkish and fleshy, with islands of yellow fat tissue.

Histologically, they exhibit pushing borders with a pseudo-encapsulation, and consist of a combination of variable amounts of stromal and epithelial components.

Associations

Radiographic features

Lesions can be any size but are typically large at presentation.

Mammography
  • well-circumscribed, round or oval mass surrounded by a thin capsule
  • comprising of both fat and soft-tissue internal densities
    • i.e. fat component appears radiolucent, soft tissue component appears radiodense
  • classic description:  "breast within a breast"  or a "slice of sausage" appearance
Ultrasound

Because it resembles normal breast tissue, the margins are often difficult to delineate. It may be seen as a well-circumscribed, solid lesion without any intralesional microcalcification. Internal echotexture is most often mixed with both hyperechoic and hypoechoic components . Lesions are soft and easy to compress.

History and etymology

Although previously reported as "fibrolipoma" or "fibroadenolipoma", they were initially termed "hamartomas" by M G Arrigoni et al. in 1971 .

Differential diagnosis

The diagnosis of hamartoma is normally straightforward, due to an extremely characteristic imaging appearance. In rare cases, a differential diagnosis may include other well-defined lesions:

Siehe auch:
und weiter:
Assoziationen und Differentialdiagnosen zu Hamartom der Mamma:
Lipom der
Mamma
Wikipedia • CC BY-SA 4.0