A 45 years old female presented for a routine screening mammogram. The patient reported painless lump for years in the left breast with no detectable changes. She denied any history of breast radiation, surgery or a family history of breast cancer. History of trauma was not taken.
The mammogram with craniocaudal (C.C) and mediolateral oblique (MLO) reveals a predominantly fatty breast and a circumscribed oval-shaped mixed density mass in the left breast which measures about 10 cm in maximum diameter with large course dystrophic calcifications and no architectural distortion, skin changes or lymph nodes enlargement (Figure 1A and B). Ultrasound was then performed to the left breast and revealed a large mass with a measurement of 10 x 2.9 cm, and large posterior shadowing caused by the calcifications obscuring the mass characterization (Figure 2). Because of the benign type of calcification, this coded as Breast Imaging Reporting And Data System 2 (BI-RADS 2) and referred for a routine screening mammogram.
Breast hamartoma (BH) is a relatively rare benign tumour and accounts for 4.8% of benign breast masses in women [1,2]. It was first described by Arrigoni et al. in 1971 . BH is formed of a mixture of fat, fibrous and a glandular tissue . This tumour also includes fibroadenolipomas, lipofibroadenomas and adenolipomas [5,6]. The pathogenesis of BH is still largely unknown; however, some reports showed that it could be related to dysgenesis and not to true tumorous process [6, 7].
BH usually presented by a painless palpable lump [8-10] and becomes no longer common by developing of screening programs [10,11]. It has usually a classical appearance in mammogram of well-circumscribed ovoid mass with mixed density of fat and soft tissue surrounded by a radiolucency area suggesting that a pseudocapsule is likely caused by displaced adjacent breast tissue [12- 14]. Benign calcifications in hamartoma have been described as small amorphous, round and rarely dystrophic types [8, 15, 16]. Moreover, it has various sonographic features and therefore ultrasound plays a minimal role in the diagnosis, and most of them show heterogenous echopattern with no posterior acoustic shadowing [17-19].
Previous reports indicated that hamartomas-associated malignancies showed atypical mammographic findings; for example, spiculated masses, focal asymmetry or suspicious microcalcifications as amorphous, or pleomorphic types The sonographic appearance as irregular margins or vertically orientated masses within the hamartoma should raise the suspicion of malignancy, and therefore warrant a biopsy [16,20-23]. This body of evidence suggested that any subtle suspicious findings even with typical mammography or sonographic findings and therefore further evaluation must be performed.
In our patient, there is a large mass with mixed density mammographic features which described as (breast within the breast) or (a slice of the sausage) appearance, makes the identification of hamartoma contains large dystrophic calcification of benign nature . The dystrophic calcification is dense and may be in-homogenous seen post-trauma including surgery, post-radiation and rarely in hyperparathyroidism. Since the history of trauma has not been taken in our case, this could be a possible cause of this type of calcification. The information gained from this case can help the radiologist to get full history in this type of calcification for differential diagnosis including malignancy.
These lesions do not own any precise diagnostic features on biopsy despite a mammographic appearance and palpable lump, because they show all the elements of normal breast tissue and may be described as ‘no pathological diagnosis’ or ‘normal breast tissue’[10, 24]. Therefore, radiological correlation is needed and any atypical presentation, biopsy should be taken.
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